Lead in the Americas : A Call for Action [1 ed.] 9780309583107

Citation preview

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

1

LEAD IN THE AMERICAS A call for action

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

2

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

3

LEAD IN THE AMERICAS A call for action

CHRISTOPHER P. HOWSON, MAURICIO HERNÁNDEZ-AVILA, AND DAVID P. RALL Editors

COMMITTEE TO REDUCE LEAD EXPOSURE IN THE AMERICAS BOARD ON INTERNATIONAL HEALTH INSTITUTE OF MEDICINE Washington, DC, USA in collaboration with THE NATIONAL INSTITUTE OF PUBLIC HEALTH Cuernavaca, Morelos, Mexico

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

4

Support for this study was provided by AETNA; the U.S. Centers for Disease Control and Prevention; Environmental Defense Fund; U.S. Environmental Protection Agency; U.S. Food and Drug Administration; International Lead Zinc Research Organization, Inc.; Johnson & Johnson Family of Companies; W. K. Kellogg Foundation Endowment Fund; Charles Stewart Mott Foundation; U.S. National Institute of Environmental Health Sciences; U.S. National Research Council/National Academy of Sciences, and the World Bank. Lead in the Americas: A Call for Action First edition, 1996 ©Copyright 1995 by the U.S. National Academy of Sciences and by the National Institute of Public Health of Mexico. All rights reserved. Additional copies of this report are available from: National Institute of Public Health Center for Population Health Research Av. Universidad 655 Col. Sta. María Ahuacatitlán 62508 Cuernavaca, Morelos, Mexico ISBN 968-6502-25-4 Library of Congress Cataloging-in-Publication Data 95-073273

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

5

Notice: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competencies and with regard for appropriate balance. The English-language version of this report has been reviewed by a group other than the authors according to procedures approved by a Report Review Committee consisting of members of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The Spanish-language version has been reviewed and approved by staff of the National Institute of Public Health of Mexico. The Institute of Medicine was chartered in 1970 by the National Academy of Sciences to enlist distinguished members of the appropriate professions in the examination of policy matters pertaining to the health of the public. In this, the Institute acts under the Academy's 1863 congressional charter responsibility to be an adviser to the federal government and its own initiative in identifying issues of medical care, research, and education. Dr. Kenneth I. Shine is president of the Institute of Medicine. The National Institute of Public Health (NIPH) (Instituto Nacional de Salud Pública) was founded in 1987, through the merger of three academic organizations that were moving in similar directions: the School of Public Health of Mexico, the Center for Research on Infectious Diseases, and the Center for Public Health Research (now Populational Health). The legal status of the NIPH is that of a semi-autonomous public organization located within the Health Sector, although the Institute has its own legal status and exercises its own budget. The headquarters of the NIPH are located in Cuernavaca, 70 km south of Mexico City, in the state of Morelos. The Center for Populational Health Research (CISP) is in charge of developing epidemiologic and health systems research which provides rational foundations for policy and decision-making. Its priorities include studies on epidemiologic transition, the health of women and children, quality of care, organization and financing of primary health care, the problem of medical employment and allocation of health resources. The Center for Research on Infectious Diseases (CISEI) is devoted to the study of bacterial, viral, fungal and parasitic ailments, including many of the so-called “neglected diseases”. In a developing country such as Mexico, these diseases continue to be of great public health importance. The Center for Malaria Research (CIP), located in the southern state of Chiapas, is linked to the CISEI. A new center also exists within the NIPH, the Center for Health Systems Research, which studies macro and micro aspects of health systems and their social context, analyzing health policies, organization and services, and their interaction with communities. The Academic Secretariat coordinates the School of Public Health of Mexico, an institution which is over 70 years old and which offers a range of Master's and Doctoral programs, as well as certification programs, to both national and international students. With these components, the NIPH combines bio-medical, populational and health systems research and human resource development. The Institute has focused its efforts on vigorously stimulating research, because the development of a better health care system requires a firm scientific basis. Thus, planning can be based on an understanding of the complex epidemiologic reality of the capabilities of different organizational arrangements for health care. Also, the formulation of health care standards can be updated incorporating new procedures whose effectiveness has been demonstrated by sound research.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

6

COMMITTEE TO REDUCE LEAD EXPOSURE IN THE AMERICAS David P. Rall,* Chair, Retired Director, U.S. National Institute of Environmental Health Sciences, Washington, D.C. J. Peter Figueroa, Principal Medical Officer Epidemiology, Jamaican Ministry of Health, Kingston, Jamaica Howard Frumkin, Chair, Department of Environmental & Occupational Health, Rollins School of Public Health of the Emory School, Atlanta, Georgia Mauricio Hernández-Avila, Director, Center for Population Health Research, National Institute of Public Health, Cuernavaca, Mexico Joan Cook Luckhardt, Director, Lead Poisoning Prevention Program, University of Medicine and Dentistry of New Jersey-SOM, Stratford, New Jersey René Méndes, Professor, Department of Preventive Medicine, Federal University of Minas Gerais School of Medicine, Belo Horizonte, Brazil Terry Oke, Administrator, Trail Lead Program, Trail, Canada Eduardo Palazuelos-Rendón, Mexico City, Mexico Ellen K. Silbergeld, Professor, Department of Epidemiology and Preventive Medicine, University of Maryland Medical School, Baltimore, Maryland Tania M. Tavares, Professor, Institute of Chemistry, Federal University of Bahia, Bahia, Brazil Institute of Medicine Project Staff Christopher P. Howson, Director, Board on International Health Kimberly A. Brewer, Research Assistant Delores H. Sutton, Senior Administrative Assistant Jamaine Tinker, Financial Associate National Institute of Public Health Conference Staff Mauricio Hernández-Avila, Director, Center for Population Health Research Kelly Scoggins, Subdirector, Academic Extensions Teresa Téllez, Logistic Assistant Carmen Alvarez, Logistic Assistant

* Member, Institute of Medicine

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

7

BOARD ON INTERNATIONAL HEALTH 1995 Barry R. Bloom (Cochair),* Howard Hughes Medical Institute, Albert Einstein College of Medicine, Hastingson-Hudson, New York Harvey V. Fineberg (Cochair),* Harvard School of Public Health, Boston, Massachusetts John H. Bryant,* Moscow, Vermont Jacqueline Campbell, The Johns Hopkins University School of Nursing, Baltimore, Maryland Richard G. A. Feachem, London School of Hygiene and Tropical Medicine, University of London, England Julio Frenk,* Mexican Health Foundation, Mexico City, Mexico Dean Jamison,* University of California, Los Angeles, California Eileen T. Kennedy, Center for Nutrition Policy and Promotion, Washington, DC Arthur Kleinman,* Harvard Medical School, Boston, Massachusetts William E. Paul,* National Institute of Allergy and Infectious Diseases and Office of AIDS Research, National Institutes of Health, Rockville, Maryland Patricia Rosenfield, The Carnegie Corporation of New York, New York, New York Thomas J. Ryan, Boston University School of Medicine and Boston University Medical Center, Boston, Massachusetts Susan C. M. Scrimshaw,* University of Illinois School of Public Health, Chicago, Illinois June E. Osborn (Institute of Medicine Liaison),* The University of Michigan School of Public Health, Ann Arbor, Michigan William H. Foege (Ex Officio),* Carter Center, Emory University, Atlanta, Georgia David P. Rall (Institute of Medicine Foreign Secretary),* Washington, DC Staff Christopher P. Howson, Director Kimberly A. Brewer, Research Assistant Delores H. Sutton, Project Assistant Jamaine L. Tinker, Financial Associate

* Member, Institute of Medicine

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

8

NATIONAL INSTITUTE OF PUBLIC HEALTH (Cuernavaca, Morelos, Mexico)

Jaime Sepúlveda-Amor, General Director Mauricio Hernández-Avila, Executive Director Center for Population's Health Research Malaquías López-Cervantes, Executive Director Center for Health Systems Research Mario H. Rodríguez-López, Executive Director Center for Research on Infectious Diseases Jose Luis Valdespino-Gómez, Academic Secretary Jose Luis Alamaraz Segovia, Administrative Director Augusto García-Besné, Internal Comptroller

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

ACKNOWLEDGMENTS

9

ACKNOWLEDGMENTS

The committee and staff are grateful for the time and effort of the many contributors to the symposium, including the plenary speakers; workshop moderators, rapporteurs, and participants; poster session presenters; agency representatives; and other participants. Through openly sharing their considerable expertise and different perspectives, these individuals brought clarity and focus to difficult issues surrounding lead exposure reduction in the Americas. Further, their active participation encouraged a remarkably free exchange of ideas and contributed to the identification of action steps for prevention and treatment of lead poisoning that are reasoned, broadly endorsed, and cost-effective. We hope that this report adequately reflects these important contributions. The committee also wishes to thank our conference hosts at the National Institute of Public Health of Mexico for their warm hospitality and excellent advance arrangements. We particularly thank Dr. Jaime Sepúlveda, Director-General, for his generosity in support of the activity and Dr. Mauricio Hernández-Avila, Director, Center for Population Health Research and committee member, for his invaluable help in organizing the conference. The committee would also like to acknowledge Drs. Christopher Howson, Ellen Silbergeld, Cristina Cortinas de Nava, and Polly Harrison for their hard work and vision in realizing this project, and we thank Ms. Carmen Alvarez, Mr. Jaime Alvarez, Ms. Norma Espinosa, Mr. Ricardo García Jiménez, Mr. Julio Rodríguez, Ms. Susana Rongel, Ms. Dee Sutton, and Ms. Teresa Téllez for having helped ensure a flawlessly run conference. Most important of all, the committee wishes to thank Ms. Kim Brewer of the IOM and Ms. Kelly Scoggins of the National Institute of Public Health for their many long hours and outstanding contributions in preparation for the meeting. Theirs are the shoulders we stood on. The committee also thanks Dr. Hugo Aréchiga, Dr. Adolfo Martínez-Palomo, Dr. Pelayo Vilar-Puig, and Ms. Phyllis Freeman for their valuable assistance in the planning of the conference. The committee and editors

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

ACKNOWLEDGMENTS

10

gratefully acknowledge the individuals who contributed substantially to the preparation of this report, including Dr. Howard Frumkin for his symposium summary in Cuernavaca and for his key role in drafting the Executive Summary; Mr. Juan Haro and Mr. José Ibarra for their valuable translation and editing of the many papers that were written in Spanish and translated into English; Mr. Terry Oke, Dr. Joan Luckhardt, and Dr. Ellen Silbergeld for their help in editing the report; Dr. Francisco Becerra for his assistance in report production; and Ms. Kim Brewer for her insightful comments and hard work in pulling the many parts of this report together. The committee also thanks the anonymous individuals who provided insightful review of the report draft. Finally, we wish to acknowledge and thank our funders: AETNA; the U.S. Centers for Disease Control and Prevention; Environmental Defense Fund; U.S. Environmental Protection Agency; U.S. Food and Drug Administration; International Lead Zinc Research Organization, Inc.; Johnson & Johnson Family of Companies; W. K. Kellogg Foundation Endowment Fund; Charles Stewart Mott Foundation; U.S. National Institute of Environmental Health Sciences; U.S. National Research Council/National Academy of Sciences; and the World Bank. Without their strong commitment to improving the health and well-being of our peoples in this hemisphere, this conference would not have occurred. DAVE RALL Chair

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

CONTENT

11

CONTENT

Preamble

13

Introduction

15

1.

Executive Summary: Action Plan to Reduce Lead in the Americas

21

2.

Setting the Stage: Historical Milestones in the Reduction of Lead in the Americas

39

3.

Session A: Keynote Address Lead at the Workplace and in the Environment: Is It Preventable? Session B: Health Effects of Lead Effects of Lead on Children's Health Effects of Lead on Adult Health Session C: Extent, Sources, and Pathways of Lead Exposure in the Hemisphere Prevalence of Exposure and Data Quality of Lead Contamination in Latin America and the Caribbean Nature and Extent of Lead Exposures and Toxicity in the Americas Session D: Case Studies of Interventions Introduction: Case Studies of Interventions Voluntary Industry Initiative: Removal of Lead Solder from Cans A Case Study in Government Regulation: U.S. Gasoline Lead Reduction Activism: The Role of Organized Labor in Promoting a Healthy Workplace Community Activism and Education: Access to New Knowledge as a Basis for Community Empowerment

49 51 57 59 66 75 77 84 91 93 94 98 105 110

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

CONTENT

4.

12

Working Group Summaries 117

Appendixes Appendix A: References Appendix B: Poster Presentations Appendix C: Analytical Methods for Blood Lead Measurement Appendix D: Technical Assistance and Information Resources Appendix E: Conference Agenda Appendix F: Conference Participants 145 147 157 173 177 191 203

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

PREAMBLE

13

PREAMBLE

We are often reminded of the interconnectedness of human endeavors and that, as a result of modern telecommunications, transportation, and our increasing economic interdependence, the world is truly becoming a “global village.” Our concerns with regard to health and the environment are, in fact, global concerns. For those of us involved in the symposium and workshops summarized in Lead in the Americas: A Call for Action, it is also clear that we live in the same neighborhood of this global village and share the same concerns about what our neighborhood of the Americas looks like, its economic well-being, its future improvement, how our actions affect our neighbors, and the extent to which we help each other. This conference presented an important opportunity to talk about the problem of lead poisoning in our shared environment and to identify common strategies to prevent this disease in our children, and workers and their families. The conference was unusual in two aspects: first, its participants represented a broad cross-section of people who have an active interest in lead exposure reduction, and second, its goals were pragmatic and tangible —to identify a set of specific actions that could be implemented immediately to reduce lead exposures in our hemisphere. The Institute of Medicine of the United States and the National Institute of Public Health of Mexico are pleased to have undertaken this important collaborative activity. We hope that this effort will mark the beginning of a long and productive interaction that, with the help of our neighbors, will improve the health, environment, and quality of life of all residents in the Americas.

Kenneth I. Shine, M.D.

Jaime Sepúlveda, M.D., Dr.Sc.

President

Director-General

Institute of Medicine, USA

National Institute of Public Health, Mexico

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

PREAMBLE 14

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

INTRODUCTION

15

INTRODUCTION

Lead poisoning is currently thought to be one of the most serious diseases of environmental and occupational origin because of its high prevalence, environmental pervasiveness, and persistence of toxicity in affected populations. Lead poisoning affects virtually all human biochemical processes and organ systems, and it can lead to a broad range of serious and often irreversible sequelae in reproduction and effects in the cardiovascular, hematopoetic, and central nervous systems. Of special concern is lead's impact on children, whose nervous systems are particularly sensitive. Among the most deleterious neuropsychological effects of lead poisoning on the very young are learning and reading disabilities, reduced psychometric intelligence, and childhood behavioral disorders. All of these have been recognized over time to occur at progressively lower levels of exposure, and all may be predictive of serious behavioral and other disorders later in life. Although more is known about the health effects and exposure pathways of lead than most other environmental contaminants, the global dimensions of the problem remain poorly understood and documented. Yet, lead poisoning is also an entirely preventable disease. Cost-effective technical and nontechnical measures to reduce sources of exposure are available. Because it is difficult and costly to control lead once it is released—and because medical treatment does not fully reverse health effects—the most useful strategies of disease prevention are directed toward controlling lead at its primary sources, for example, through engineering measures in the workplace or replacement of lead with safer substances. There are a number of improved practices that can reduce exposures in cases where lead cannot be replaced. These practices include education and training, surveillance of exposures and health effects, and, in occupational settings, use of personal protective equipment for workers exposed to lead. In most countries of the world, however, the technical means and knowledge required to recognize and reduce environmental and occupa

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

INTRODUCTION

16

tional exposures to lead do not exist. National policymakers are thus seriously disadvantaged in their ability to make adequate assessments and appropriate decisions about public health investments and allocations of human and financial resources. As a result, opportunities to incorporate primary prevention of environmental diseases into economic and social development programs may be missed. Assistance organizations at all levels, including international development and technical assistance agencies, local nongovernmental organizations (NGOs), and community-based environmental action groups have similar, corresponding difficulties. Recognizing this, in 1993 the Board on International Health of the Institute of Medicine proposed an international symposium and associated workshops on the topic of lead and health. The objectives of the activity were twofold: to provide a forum for the exchange of current information on major sources and toxic effects of lead exposure and to offer a neutral venue for North and Latin American and Caribbean policymakers, private sector representatives, research scientists, community representatives, and health professionals to identify cost-effective strategies for reducing lead exposures in the hemisphere. The symposium was to: (1) review and assess what is known about the magnitude of lead toxicity as a public health problem in selected countries of the Americas; (2) review and assess what is known about the sources of lead in the Americas, levels in various environmental media, and the uses of lead that increase human exposure; (3) evaluate transnational impacts of lead, including environmental fate and transport, and transboundary movements of lead in commerce, including recycling and waste disposal; and (4) develop a framework for the identification, analysis, and articulation of integrated control strategies to reduce environmental and occupational exposures to lead and consequent human disease. The conference was designed to build on the solid evidentiary base provided, in part, by past efforts of the National Academy of Sciences (NRC, 1980, 1993) and other influential bodies (Alliance to End Childhood Lead Poisoning and EDF, 1994; ATSDR, 1988; CDC, 1991; National Center for Lead-Safe Housing, 1995; OECD, 1994). The Board decided to focus on lead exposure reduction in the Americas for four general reasons: One, many countries in North and Latin America and the Caribbean are beginning to respond to environmental concerns and are looking for guidance in the allocation of funds for environmental research and intervention. The region has already seen agreements between the public and private sectors with respect to reducing environmental lead.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

INTRODUCTION

17

Two, the growing liberalization of U.S. trade with Mexico and the other Latin American countries—and the environmental challenges this presents, both with respect to the environment and to the transborder movement of goods and wastes—requires timely development of acceptable, consistent, and cost-effective strategies for preventing diseases in the region. Three, the close cultural similarities among countries in the region will increase the likelihood that lead poisoning prevention strategies successful in one region of the Americas will provide a useful framework for public health policy elsewhere in the hemisphere. Examination of the successful dialogue between the public and private sectors in Mexico in reformatting ceramic glazes, for example, may offer a model for comparable successful strategies in other countries of the Americas. Four, this project builds on a growing portfolio of IOM activities, conducted in collaboration with institutions in Mexico and Canada, that focus generally on review of transfers of knowledge of health risks and benefits related to the economic, social, and cultural integration of Mexico, the United States, and Canada that is occurring as a result of accelerating trade liberalization. This growing partnership was deepened by the decision of the IOM and the National Institute of Public Health of Mexico to collaborate in hosting the conference, which was ultimately held at the National Institute of Public Health's main campus in Cuernavaca, Morelos, Mexico. The advisory committee of 11 members from Latin America, the Caribbean, and North America was chosen to oversee the planning and implementation of the symposium and workshops. The committee had a broad range of expertise in international health, public health, health policy, toxicology, environmental and occupational epidemiology, environmental engineering, economics, and community-based intervention strategies for environmental risk reduction. The committee met first in November 1994 in Washington, D.C., to plan the agenda for the symposium and workshops. The subsequent conference was held over a three-day period, 8-10 May 1995. Days 1 and 2 of the symposium each began with a plenary session featuring presentations on the health effects and treatment of lead toxicity, the prevalence and severity of lead toxicity in the hemisphere and issues of data quality, and major sources and pathways of lead exposure. There were also four case studies of lead exposure interventions highlighting examples of voluntary industry initiatives and the roles of the federal sector, international organized labor, and community activism and education in promoting

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

INTRODUCTION

18

reduced exposure levels. In addition to the 10 plenary presentations, 28 posters presenting data on various aspects of lead and health in the Americas were on display throughout the conference. Afternoons featured six working group sessions on the following topics: gasoline; paint; ceramicware glazes; industrial and occupational health; food, water, and waste disposal; and techniques for improved lead surveillance and monitoring. Each session was responsible for identifying specific action steps that could be tailored by participants to regional, federal, or local needs, as required, to reduce human lead exposure across the Americas. The final plenary session on Day 3 featured the presentations of the working groups and identification of action steps that were common across all six groups. The conference also offered a workshop on Analytic Methods for Blood Lead Measurements sponsored by the U.S. Centers for Disease Control and Prevention (CDC). This report of the conference, which is being published in both English and Spanish versions, contains four chapters and six appendixes. Chapter 1 summarizes the findings, conclusions, and recommendations of the symposium participants for the prevention of lead poisoning in the Americas. Chapter 2 describes the history of public health concerns about lead poisoning and the voluntary and regulatory steps taken to date to reduce human lead exposures. Chapter 3 provides summaries of the plenary session presentations, and Chapter 4 summarizes the findings of the six working groups. The report also features six appendixes: Appendix A provides a list of references cited; Appendix B offers descriptions of the poster presentations; Appendix C summarizes the workshop on Analytic Methods presented by the CDC; Appendix D offers brief descriptions of federal and private organizations involved in lead poisoning prevention activities in the hemisphere and provides contact information for readers interested in obtaining further information; Appendix E offers the conference agenda; and Appendix F the list of conference attendees with contact information for each. The committee recognizes that the strategies for recognizing and eliminating lead poisoning agreed upon by the symposium participants are based predominantly on the successful experiences of the United States, Europe, and those of the Finnish Lead Program in the developing world as reported Dr. Jorma Rantanen, the keynote speaker. It was the consensus of participants, however, that these successful experiences are both relevant and applicable to prevention and control of lead poisoning in the Americas. The committee also recognizes that the general set of prevention and control strategies identified by symposium participants will need to be adapted, at least in part, for and by specific countries. It will have to take into account

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

INTRODUCTION

19

differences in cultures and politics, levels of technological development and economic resilience, predominant sources of lead, and the distribution of exposures. Also, in every country, individuals from a variety of disciplines, working at different levels in the public and private sectors, will need to be substantively involved in the tailoring and implementation of these action steps. Regional, country, and local policymakers should include in their decisionmaking the broad range of interested, and affected, parties, including health care providers and representatives of community-based environmental action groups. In particular, it is important to involve leaders in industries and businesses that use or produce lead in their merchandise or as a by-product of manufacturing or use. It was the consensus of conference attendees that the building of such broadbased coalitions is crucial to the acceptance and success of actions to reduce environmental and occupational lead exposures across the countries of the Americas.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

INTRODUCTION 20

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

21

CHAPTER 1

Executive Summary: Action Plan to Reduce Lead in the Americas

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

22

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EXECUTIVE SUMMARY: ACTION PLAN TO REDUCE LEAD IN THE AMERICAS

23

EXECUTIVE SUMMARY: ACTION PLAN TO REDUCE LEAD IN THE AMERICAS The consensus of the conference participants can be summarized clearly and directly: for many populations in the Americas, human exposure to lead is excessive, produces disease, and must be reduced. The magnitude of this exposure, and the pathways through which it occurs, vary from country to country and are not always well-characterized. Leaded gasoline remains a major source of exposure in Argentina, Suriname, Ecuador, Peru, and probably in other countries as yet undocumented, but it has been largely eliminated in Brazil, Canada, and the United States. Lead-glazed ceramic (LGC) is commonly used to cook or store food in Mexico, Ecuador, and probably in many other countries of the Americas. All countries have many point sources of lead emissions, such as smelters, battery plants, and scrap metal recovery facilities. These range from large factories to microenterprises (in many countries of the region, these are family-run businesses that are usually unregistered by governmental agencies and are difficult to access and regulate). Some countries recognize problems with lead paint, but in patterns that appear to vary considerably. Although quantitative information about levels of lead in air, water, and food is available for relatively few countries, the data that are available suggest the presence of levels that pose significant hazards to health. Systematic population surveys of blood lead levels have only been undertaken in the United States. Less systematic data compiled elsewhere point to some serious problems. Average blood lead levels in children in some of these surveys are as high as 39 µg/dl, and the proportion of children with blood lead levels above 10 µg/dl in some studies is 100 percent. Clearly, lead exposure is widespread, albeit heterogeneous. Hence, conference participants recognized that the optimal approach to prevention will vary from country to country, as will the political and economic strategies needed to achieve success. These are issues to be decided by communities, workers, industries, public health professionals, clinicians, political leaders, and other stakeholders in each country. More

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EXECUTIVE SUMMARY: ACTION PLAN TO REDUCE LEAD IN THE AMERICAS

24

over, conference participants were mindful that many countries of the Americas were not represented at the conference. Accordingly, those present did not attempt to reach consensus on specific recommended actions. Nevertheless, the major sources of lead exposure are known, primary prevention is imperative and attainable, and those present agreed that an Action Plan is necessary to achieve prevention. They hoped that this general approach would be of use in the Americas and in other regions. Critical steps of the Action Plan include: • • • • • •

Assemble and share the necessary information; Build capacity and train the necessary personnel; Build political will; Involve the target community; Make the needed technical changes; Determine and communicate the benefits, and costs, of eliminating lead from industrial processes and uses; • Identify cases, prevent further exposures, and provide clinical care; • Evaluate the results; • Follow-up. There was universal agreement that primary prevention through technical change is necessary and appropriate, and consistent with proven principles of public health. Specifically, conference participants agreed on a wide-ranging set of recommendations: • • • •

Move toward the elimination of lead in gasoline, ceramic glazes, paints, and solder on food cans; Strictly limit workplace exposures to lead and releases from macro- and microindustrial sources; Implement surveillance of high-risk populations and environmental monitoring; Focus on interventions that have been shown to be cost-effective and sustainable in countries of the Americas and elsewhere in the world; • Conduct evaluation research, so that the success and cost-effectiveness of prevention and control strategies can be assessed on a regular basis; • Ensure the involvement of all parties having a direct interest in reducing lead exposure, including government agencies, large and small industries, organized labor, health care providers, and community groups.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EXECUTIVE SUMMARY: ACTION PLAN TO REDUCE LEAD IN THE AMERICAS

25

More broadly, conference participants recognized the need for continued economic development of the region as a means of providing alternatives for those who currently earn their living in cottage industries that contribute to lead exposure and for generating the capital necessary to invest in clean technologies and abatement. The following paragraphs describe the generic components of the Action Plan to control lead exposure with which the majority of participants concurred. The first discussed is technical change, the centerpiece of efforts to control lead exposure.

MAKE THE TECHNICAL CHANGES Conference participants agreed that specific technical changes to reduce lead exposure are necessary throughout the Americas. Attendees were cognizant of the financial, cultural, and political barriers that exist, and of the important competing priorities in development generally and in health specifically. Nevertheless, the following changes were recommended. The conference participants call on the countries of the Americas to move toward the elimination of lead in gasoline. This recommendation is supported by several facts. First, there is clear evidence that human exposure to lead from gasoline is widespread, and that eliminating lead from gasoline lowers population blood lead levels by reducing lead in air, foods, and dusts and soils. Second, there is a readily available alternative: unleaded gasoline. Third, that many countries in the Americas have already eliminated or reduced the use of tetraethyl lead in gasoline indicates that this change is feasible. Fourth, all major constituencies, including many of the representatives from manufacturers of tetraethyl lead attending the conference, agreed that lead in gasoline needs to be phased out. The conference participants call on the countries of the Americas to move toward the elimination of lead in manufactured food containers. This recommendation is also supported by several facts. First, there is good evidence that the use of lead-containing solder in food cans results in contamination of food. (This view was initially countered by some members of industry, who noted correctly that the soldered surface does not necessarily contact the food in the cans. Research has demonstrated, however, that contamination of the interior surface of the cans generally occurs during the production process and is in many cases unavoidable.) Second, technical

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EXECUTIVE SUMMARY: ACTION PLAN TO REDUCE LEAD IN THE AMERICAS

26

and economically affordable alternatives are readily available. Third, the success of several countries in eliminating lead-containing solder from cans demonstrates that this change is feasible. Fourth, the substitution of welded joints for lead-containing solder has been shown to derive the following commercial benefits: a 3-5 percent reduction in raw materials, resulting from the smaller welded joint; no net additional costs from retooling because material costs most often offset equipment costs; and a smaller welded joint provides a larger surface area for advertising, and a potential for increased market share. Conference members recommended that each country, through collaboration among its public health authorities, canning industry, and other interested parties, move rapidly toward eliminating the use of lead-containing solder in food cans. The conference participants call on the countries of the Americas to move toward the elimination of lead in ceramic glazes. Members of the working group on ceramic glazes noted that there is inadequate information about the extent of LGC use in most countries of the Americas, or on the relative contribution of LGC as a source of human exposure. Mexican data demonstrate, however, that LGC pottery and cookware are widely used and can be an important source of lead exposure among women of reproductive age. Moreover, it is not only the users of LGC products who are exposed to lead; the artisans and manufacturing workers who make these products—and their families—also sustain lead exposure, sometimes at levels much higher than those found in users. Technical alternatives are readily available, although further research is necessary to optimize and verify their performance in some situations. (For example, some alternative glazes require very high firing temperatures that cannot be attained in the simple kilns of small-scale producers.) The phaseout of LGCs in the Americas will be a complex challenge because the manufacturing of ceramics is extremely heterogeneous, ranging from large industries to family enterprises, and practices are in some cases based on entrenched cultural traditions. The conference participants emphasized that participation of all players, and special sensitivity to the needs of small producers, will be required to achieve a phaseout of LGCs. The conference participants call on the countries of the Americas to move toward the strict control of lead in paint. Members of the working group on leaded paint noted that, as with LGC, important data are missing on the use of lead in paint in the Americas. The extent of its use and its relative

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EXECUTIVE SUMMARY: ACTION PLAN TO REDUCE LEAD IN THE AMERICAS

27

contribution as a source of human lead exposure are not well characterized in most countries. Data from the United States indicate, however, that lead-based paint is a prominent source of lead exposure among U.S. children. In addition, the use of lead-based paint exposes workers who manufacture, remove, apply, and work near it, and their family members, and results in lead-containing dust in households and the general environment, potentially affecting many more people. Comprehensive control of this source of exposure is extremely complex, for several reasons. First, in some countries lead-containing paint is already in place in millions of homes, commercial facilities, and structures such as bridges; removing lead from newly manufactured paint would not reduce exposure from these sources. Second, lead-containing paint is used in a wide range of applications—from toys to artists' supplies, from homes to bridges. Third, efforts to control lead at the point of use is difficult, since paints are applied by millions of individual painters and homeowners. In contrast, it is feasible to control lead in paint at the point of manufacture, because paint formulaters tend to mix feedstock pigments—many containing lead—from a limited number of manufacturers. Also, alternatives are currently available, including paints with very low lead content and paints without lead, although the costs of these paints tend to be considerably higher than those of lead-based paints in most countries of the Americas. In summary, the conference participants recognized the need for more data on the nature and extent of the use of lead-based paint in the Americas, and on the magnitude of associated human lead exposure. They also agreed, however, that countries of the Americas should immediately begin to take steps to eliminate lead from paint, especially in residential applications, but also in commercial applications. The conference participants call on the countries of the Americas strictly to limit workplace exposures to lead. The hazards of occupational lead exposure have been well recognized for centuries, and international guidelines on limiting exposure have been available for decades. Members of the working group on occupational and industrial health endorsed the need for enforceable limits on lead levels in workplace air and for medical removal with full pay and job security for workers whose blood lead levels exceed a threshold, and they recommended that the acceptable threshold levels used as a basis for enforcement be standardized to the extent possible across the countries of the region. Working group members endorsed several additional general components of occupational lead exposure con

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EXECUTIVE SUMMARY: ACTION PLAN TO REDUCE LEAD IN THE AMERICAS

28

trol: (1) primary prevention through adoption of lead-free technologies wherever possible, and through strict control technologies otherwise; (2) enforceable hygiene practices in workplaces such as washing facilities, lockers for clothes changing, smoking restrictions, and personal protective equipment where appropriate; (3) regular medical surveillance of exposed workers, including monitoring of blood lead levels; and (4) worker training regarding lead hazards. Relatively complete programs are in place in Colombia, the United States, Canada, and several other countries of the Americas. All countries should strive to implement such programs, with the active involvement of labor organizations, industries, government agencies, and health care providers. The conference participants call on the countries of the Americas to implement appropriate public health initiatives such as surveillance of high-risk populations, environmental monitoring, and education of the public and workers. The preceding recommendations are directed to primary prevention, and are centered on technical interventions that will directly reduce lead exposure. The final recommendation addresses a variety of public health initiatives, many of which are also discussed in the context of specific sources of lead exposure. Surveillance programs are necessary to identify cases of lead toxicity for early intervention and treatment, monitor population trends, identify and quantify principal sources of lead exposure, evaluate the efficacy of interventions, and support education efforts. Successful surveillance programs should be simple and inexpensive, and to the extent possible should take advantage of existing programs and facilities. Surveillance should include both biological sampling of high-risk populations and environmental sampling of known or suspected sources of exposure. As noted above, exposure assessment is especially important with regard to ceramics and paints, sources for which the magnitude of exposure in many countries remains largely undefined. It is essential that such programs include provisions for control and follow-up of excessive blood lead and environmental lead levels, and that medical confidentiality in the workplace be safeguarded. A separate but linked public health effort is education. It is essential that vigorous educational efforts be directed at policymakers, health care providers, workers, industrialists and managers, and members of the public. Of special importance, health care providers need to be trained to recognize and respond to lead toxicity, and workers need practical training in the recognition and prevention of lead toxicity. Training and surveillance can often be effec

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EXECUTIVE SUMMARY: ACTION PLAN TO REDUCE LEAD IN THE AMERICAS

29

tively linked. Such efforts can help to build the political will to control lead exposure, and can enable exposed persons to take steps to protect themselves. ASSEMBLE AND SHARE THE NECESSARY INFORMATION Any major public health program must be based on solid data. But lead is a unique hazard: a great deal is known about lead toxicology, and the benefits of decreasing exposure have been established beyond doubt. There was widespread agreement among conference participants that steps to control lead exposures need not, and indeed should not, await further physiologic or toxicologic data. Further information for decisionmaking is needed, but only in limited and specific ways. Two kinds of information, now only partially available, are particularly important: patterns of lead exposure, and methods of control. The extent of lead use, its distribution in the environment, and the extent of human absorption, are only incompletely characterized in much of the hemisphere, particularly at the local level. For example, participants in the workshop on lead in ceramics noted the paucity of quantitative data on the use of LGCs in Ecuador, Bolivia, Peru, and many other countries of the Americas. In general, conference participants agreed that the populations at highest risk of lead exposure, and the settings in which lead exposure is most likely, must be identified, and their exposures quantified. This highlights the fundamental role of surveillance and monitoring, including both biological testing and environmental sampling. Such research does not extend the frontiers of science, but it serves time-honored and essential functions: it documents the existence and magnitude of problems, translating the theoretical and distant to the immediate and local. Similarly, conference participants agreed that there is a need for further information on methods of control. In some cases this involves narrowly technical information. For example, participants in the workshop on food, water, and waste disposal noted that a Japanese technology—lining existing lead pipes with plastic to minimize leaching of lead into drinking water—may have promise, but that information on the cost and efficacy of this technology is not readily available. In other cases the needed information could extend beyond the technical to the social and political. For example, what are the practical, affordable alternatives to backyard battery-recycling operations in countries with few resources, and how can they be successfully introduced? The research methods applicable

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EXECUTIVE SUMMARY: ACTION PLAN TO REDUCE LEAD IN THE AMERICAS

30

here range from historical case studies to environmental engineering investigations to cost-benefit analyses. There was a clear consensus that more research is necessary to achieve control of lead toxicity in the Americas, but it must be research that is targeted, action-oriented, and directly relevant to prevention within the country or region in which it is conducted. One example of this type of analysis endorsed by conference participants would be an extension of the 1994 Pan American Health Organization survey conducted by Drs. Isabelle Romieu and Marina Lacasana, whose initial results appear in this volume. Unfortunately, requests for information yielded responses from only 16 of 28 nations surveyed, leaving considerable uncertainty, especially for the Caribbean countries, and the authors were unable to ascertain whether a nonresponse from a given country indicated just that or a true lack of data. Moreover, research results must reach those who need to know. There are many important audiences, including government policymakers, decisionmakers and technical staff in large industries, representatives of the microindustries that form much of the economy in Latin America and the Caribbean, organizations that represent labor and communities, health care providers in public health agencies and on the clinical front lines, and the media. To be effective, research results must be translated into terminology and formats that can be readily understood by these important and diverse audiences. Education and dissemination are therefore essential components of research. Existing knowledge about the health effects of lead must be shared in a culturally appropriate manner with members of the public; in particular, parents must be taught the hazards lead poses for their children. Public health workers also need to be aware of lead as a hazard. Similarly, workers in industries where lead exposure can occur must be informed about lead hazards, recognition of early signs and symptoms of toxicity, and means of prevention. Approaches such as chemical information sheets, which detail chemical health hazards and are currently being used with success in the United States, Canada, Mexico, and a limited number of other countries in the Americas; product labeling; mandatory worker training sessions; and school-based training should be considered. Public health workers have a special responsibility to communicate with policymakers, informing them of lead hazards and advocating control measures. Through such channels of communication, necessary information once assembled can be translated into preventive action.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EXECUTIVE SUMMARY: ACTION PLAN TO REDUCE LEAD IN THE AMERICAS

31

BUILD CAPACITY AND TRAIN THE NECESSARY PERSONNEL Many countries of the Americas lack the necessary human and technical infrastructure to control lead exposure. For example, participants in the surveillance workshop noted that many countries have no adequately equipped laboratories for blood lead testing, no technicians trained to manage such laboratories, and no sanitarians or engineers trained and equipped to carry out field measurements of environmental lead. Addressing these deficits should, therefore, be an important part of any hemispheric plan to reduce lead exposure. Workshop participants urged North-South and South-South collaboration to offer assistance in technical training and equipping in countries that lack the infrastructure to develop lead surveillance programs. The example of Europe was cited on occasion; there, as part of the process of economic integration, cross-training of industrial hygienists from various countries has been highly successful. One promising initiative was discussed by Dr. Henry Falk and Dr. Robert Jones of the U.S. Centers for Disease Control and Prevention (CDC). They described the CDC's lead testing proficiency program, which includes careful provisions for quality control and is free to participating laboratories. Dr. Falk indicated that this program is available to laboratories throughout the hemisphere, and that CDC might assist in training laboratory personnel in each country or region, with the recognition that testing equipment would have to be purchased with funds from other sources. A second promising initiative was introduced by Dr. Rob McConnell of the Pan American Center for Human Ecology and Health (ECO), who discussed plans for regional capacity building in environmental epidemiology. A skilled complement of professionals, with expertise in laboratory methods, epidemiology, industrial hygiene, environmental engineering, and clinical medicine, is essential for the successful control of lead exposure in the Americas. BUILD POLITICAL WILL Even if information is readily available, and even if trained personnel are in place, lead exposure will not be easily controlled. Entrenched traditions govern such practices as ceramics manufacturing and use. Powerful financial interests stand in the way of some changes. Limited resources preclude such interventions as the wholescale upgrading of refinery processes to allow for reformulation of gasoline with large amounts of highoctane components as a replacement for leaded fuel.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EXECUTIVE SUMMARY: ACTION PLAN TO REDUCE LEAD IN THE AMERICAS

32

For these reasons, each country must build the political will to implement changes. How to do so will, of course, vary from country to country. Veterans of public health campaigns, especially in the United States, spoke of the success of strict government regulation and offered persuasive historical examples—for example, elimination of leaded gasoline. Workshop participants generally agreed, however, that cooperative approaches including industry, government, the health sector, labor, and others, were preferable. An underlying theme of the conference, and of the recommendations that emerged, was the necessity of multisectoral cooperation and “buyin” in achieving prevention. Some of the representatives of the lead industry who were present admirably exemplified this approach, acknowledging that leaded gasoline is a product with a limited commercial life, and joining in dialogue about its phaseout in coming years. Conference participants also agreed on the importance of presenting data, where available, on the cost-effectiveness of reducing lead in the environment. Communicating the economic advantages of strategies to reduce lead exposure can be an important instrument for building political will. Dr. Tania Tavares, in the working group on food, water, and waste disposal, introduced an analytical framework relevant to building political will. For any proposed change, the following questions are addressed: • • • • •

What is the necessary change? How is it to be accomplished? Who must act to do it? What incentives exist, or can be created, to encourage the change? What supporters might promote the change?

For example, in considering the elimination of lead solder in food cans, the working group noted that action must be taken by the canning industry, and identified important incentives that have been realized by companies that have made the change: savings in raw materials, cost neutrality of the change, decreased liability, and increased market share. Through such an analysis, and through active advocacy directed toward decisionmakers in government, industry, the health sector, and elsewhere, the political will to control lead exposure must be built. INVOLVE THE TARGET COMMUNITY The improvement of health is a multidisciplinary process. While conference participants acknowledged that environmental change (for example,

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EXECUTIVE SUMMARY: ACTION PLAN TO REDUCE LEAD IN THE AMERICAS

33

removal of lead from gasoline, implementation of occupational lead exposure controls) must be central to any effective national or regional strategy to reduce lead exposure, they also agreed that sustained action requires that the affected (target) population be aware of the health problem and understand and accept the available means of preventing or controlling that problem. This can be accomplished only through the exchange of health information, appropriately geared to the needs and understanding of the community, and through engaging community members in the identification of problems and strategies to solve them. Accordingly, there was broad consensus among conference participants that active community involvement is a necessary prerequisite for effective prevention and control of lead poisoning across the hemisphere. Participants agreed that the growing movement to involve community members and other local “stakeholders” in health promotion and disease prevention and control programs has demonstrated clearly that such individuals can be vital to the development of innovative and sustainable solutions at the local level. The poster and plenary presentations of successful community-based programs—such as the Alameda County Lead Poisoning Prevention Program (U.S.A.), Trail Community Lead Task Force (Canada), Johnson and Johnson Corporation/New Jersey Head Start Association (U.S.A.), United Parents Against Lead (U.S.A.), and Tijuana Lead Program of El Colegio de la Frontera Norte (Mexico)—support this approach as an important vehicle for lead poisoning prevention and control. Conference participants agreed that involving a broad range of affected and interested parties—which could include parents and other family members, workers, local public health professionals and health providers, community-based nongovernmental organization (NGO) personnel, other appropriate public agency representatives (for example, on behalf of housing, labor, and insurance commissions), and individuals representing industry—in program development and implementation is central to any effective and sustainable strategy. DETERMINE AND COMMUNICATE THE BENEFITS, AND COSTS, OF ELIMINATING LEAD FROM INDUSTRIAL PROCESSES Reducing or eliminating lead exposure can be profitable in the long run, as shown in the case studies and workshops of U.S. gasoline lead reduction and removal of leaded solder by the Mexican canning industry. Some measures to reduce or eliminate lead, however, require initial costs. A

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EXECUTIVE SUMMARY: ACTION PLAN TO REDUCE LEAD IN THE AMERICAS

34

leading example is the removal of lead from gasoline, owing to the costs of reformulating unleaded gasoline to achieve equivalent octane. Another example is the removal of lead-containing paint from existing housing. Other public health efforts, such as establishing lead testing laboratories and providing population surveillance and product testing, also entail costs. Offsetting these costs, in some instances, may require funding from external sources. The preliminary list of federal and private organizations involved in lead poisoning prevention provided in Appendix D of this report provides a means of obtaining preliminary information toward this end. But there also are costs associated with not reducing or eliminating lead exposure. These include the direct medical costs of such lead-related conditions as hypertension (and resulting strokes and myocardial infarctions) and renal failure, the direct costs of remedial education for children with learning impairments, and the opportunity costs incurred when potentially creative, productive people cannot fully contribute to their communities and nations. There are also the enormous, but unquantifiable, “costs” in human suffering of those with lead poisoning and their families. Whereas the costs of reducing lead exposure are generally short-term costs, the costs of not reducing lead exposure continue to accrue over many years. The conference participants noted and lamented the relative paucity of careful cost-benefit analyses of reducing lead exposure. Although cost-benefit analyses often have important limitations, such as neglect of equity issues and inability to quantify some costs, they have the virtue of making certain benefits explicit. In the past, industries required to limit emissions or to change processes have sometimes argued that such changes are financially prohibitive. These costs, however, can be greatly overstated–as noted by the removal of lead solder from Mexican cans described by Alfonso de León. In other instances, a requirement to limit emissions can lead to innovative technologies and increased efficiency, actually saving money. Several examples of this kind were cited at the conference. For the benefit side of the equation, a thorough analysis would consider the diseases and disability avoided by reducing exposure, with the potentially large associated savings to society. Such thorough analyses might well demonstrate that reducing lead exposure not only improves public health, but is also eminently affordable.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EXECUTIVE SUMMARY: ACTION PLAN TO REDUCE LEAD IN THE AMERICAS

35

IDENTIFY CASES, PREVENT FURTHER EXPOSURES, AND PROVIDE CLINICAL CARE The major focus of the conference was on reducing lead exposure through primary prevention, and on detecting lead toxicity promptly to permit early intervention (secondary prevention). Reducing morbidity among victims of lead toxicity (tertiary prevention) was also addressed. The principal intervention in cases of lead toxicity is removal from exposure. Nevertheless, two other approaches currently not used in most countries of the Americas deserve attention: medical treatment of lead toxicity and rehabilitation. Medical treatment of lead toxicity rests primarily on chelation therapy, using calcium disodium edetate (EDTA), British antilewisite (BAL), penicillamine, succimer (DMSA), or a combination of these (Frumkin, in press). Chelation therapy is widely accepted in the treatment of lead encephalopathy, with extreme elevations of blood lead (in the range of 80–100 µg/dl or higher), since it promotes rapid reduction in circulating lead and accelerated excretions of lead. The efficacy and safety of chelation in treating low to moderate elevations of blood lead, however, are not well established. Data from well-conducted clinical trials (one is under way in the United States) are badly needed. Another problem is that these medications are very costly, especially for poorer nations, and some require intensive medical oversight. To the extent that efficacy is established, mechanisms to make chelating agents available at affordable prices will need to be developed. Lead toxicity can have irreversible effects on the nervous system. Little information is available on the optimal management of affected persons, or on the efficacy of rehabilitation treatment. However, as more leadexposed individuals reach older ages, where the effects of aging and cumulative lead toxicity combine to cause cognitive and affective dysfunction, this issue will take on increasing importance. Again, further research will be necessary to clarify any effective clinical approach. EVALUATE THE RESULTS The countries of the Americas all face competing demands for social investment and for the attention of public health workers. Accordingly, it is essential to evaluate the results of interventions that aim to reduce lead exposure. Careful outcome studies, from individual workplaces to countrywide studies, should be initiated when interventions are launched. In this volume, for example, Dr. Robert Scala has described the association

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EXECUTIVE SUMMARY: ACTION PLAN TO REDUCE LEAD IN THE AMERICAS

36

between removing lead from gasoline in the United States and declining blood lead levels in the population, based on the work of Pirkle and colleagues (Pirkle et al., 1994). Data from such studies will help to assess both the efficacy and cost-efficiency of specific interventions, guide future strategies, and provide a valuable resource for public health planners throughout the region and the world. FOLLOW-UP Even the best-designed public health prevention and control programs will yield little benefit if their implementation and maintenance are given insufficient care and attention. Acknowledging this point, conference participants concurred strongly on the need for continued, active follow-up of programs deriving from the Action Plan described in this summary. Followup should include identification of broadly accepted milestones amenable to ongoing evaluation, as well as mechanisms to ensure program sustainability. Milestones amenable to evaluation can include, for example, targeted reductions in blood lead levels in the general population or in populations at special risk, such as the occupationally exposed. The successful achievement of these and other milestones will depend on the acceptance and implementation of the components of the Action Plan described above. Sustainable solutions can only be guaranteed when there is effective communication and coordination of activities to reduce lead exposures, both within and across local, country, and regional levels. At the country level, effective linkages should include responsible parties in government, national and local NGOs, and community coalitions. Because the responsibilities for health actions in the Americas—as elsewhere in the world—are being progressively transferred from central to local governments, and ultimately to the individual, public education and other mechanisms that promote long-term changes in the health actions of communities and the health behaviors of individuals are becoming an increasingiy important basis for sustainability. At the regional level, linkages between bilateral and multilateral organizations such as the Pan American Health Organization (PAHO), the U.S. Agency for International Development (USAID), the Inter-American Development Bank, and the World Bank and country and local governments can be particularly productive. Examples of such linkages include PAHO's Regional Plan for Investment in Health and the Environment, which seeks to engage countries and donors in a common agenda for improvement, and

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EXECUTIVE SUMMARY: ACTION PLAN TO REDUCE LEAD IN THE AMERICAS

37

USAID's Regional Housing and Urban Development Office (RHUDO) for Latin America, which sponsors initiatives to improve urban health. Both programs produce data that can be used to better characterize the dimension of the lead hazard in the Americas and promote interventions to address specific problems. These kinds of programs should be encouraged in advancing a regional agenda for lead poisoning prevention and control. In summary, the conference participants came to two general conclusions. The first conclusion was definite and specific: lead exposure, in its various forms, should be reduced or eliminated throughout the countries of the Americas. The second conclusion was flexible and general: the preferred approaches to preventing lead poisoning will vary from country to country, depending on the kinds of exposure that exist and the social, political, and economic circumstances of the local environment. The Action Plan described in this summary provides generic guidelines for national efforts to prevent lead poisoning that allow for adaptation in each country. Finally, the conference participants emphasized the importance of collaboration among constituencies such as industry, labor, environmentalists, communities, and government, as well as among countries facing comparable challenges.

Note: The Committee to Reduce Lead in the Americas is indebted to one of its members, Dr. Howard Frumkin, for having provided the substantive first draft of this chapter based on his plenary summation in Cuernavaca.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EXECUTIVE SUMMARY: ACTION PLAN TO REDUCE LEAD IN THE AMERICAS 38

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

39

CHAPTER 2

Setting the Stage: Historical Milestones in the Reduction of Lead in the Americas

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

40

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

SETTING THE STAGE: HISTORICAL MILESTONES IN THE REDUCTION OF LEAD IN THE AMERICAS

41

SETTING THE STAGE: HISTORICAL MILESTONES IN THE REDUCTION OF LEAD IN THE AMERICAS ELLEN SILBERGELD*/CHRISTOPHER HOWSON** KIMBERLY BREWER**

Lead poisoning is one of the most serious and prevalent diseases of environmental and occupational origin in the Americas. Yet, it is entirely preventable through the identification and control of exposures to lead. Lead poisoning is caused by acute or chronic exposures to lead through contamination of air, drinking water, foods, paint, soils, and dusts, as well as through the use of products that release lead such as leaded glazes on ceramicware and cans with lead solder. Lead poisoning is emblematic of the blurring of occupational and environmental health problems for three reasons: first, lead industries are often major sources of ambient environmental contamination; second, small-scale or cottage industries that use or handle lead increase the rate of exposure for workers and their families employed in these sectors; and third, workers in mining, industry, and construction can bring lead dusts home on their clothing or skin, thus exposing other family members to lead. Lead poisoning in the Americas, as elsewhere, is both a product of economic development and an indicator of economic and other disparities within societies. Too often, the poor and disadvantaged are at highest risk for lead poisoning because of employment in hazardous industries or residence near lead sources or in shelters containing paints with high levels of lead. Certain traditional practices of ceramic glazing and the use of lead-containing cosmetics and folk medicines also expose significant populations in our hemisphere to high levels of lead. Knowledge of the dangers associated with lead extends almost as far back as human discovery of the useful properties of this common element. In the Americas, lead became an important part of early economic development soon after the arrival of the Europeans. The Spanish, for example, began

* University of Maryland Medical School, Baltimore, M.D. ** Institute of Medicine, Washington, D.C.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

SETTING THE STAGE: HISTORICAL MILESTONES IN THE REDUCTION OF LEAD IN THE AMERICAS

42

the extensive exploitation of the Zacatecas silver mines (which contained lead in the ores) in Mexico in the sixteenth century, and the Portuguese and Spanish brought lead-based glazes to the traditional ceramicists of the Americas. In North America, lead mines were quickly developed in the mid-Atlantic region, and lead-based paints were one of the first nonagricultural exports of the English colonies. As shown in Figure 2-1, these events in the American hemisphere contributed significantly to worldwide lead use and left their residues in environmental sinks as remote as Greenland (Hong et al., 1994). Indeed, the greatest impact of lead on human and environmental health was an American contribution: the invention and use of alkyllead (tetraethyl lead) as an antiknock additive to gasoline, which has resulted in the uncontrolled dispersion of millions of tons of lead throughout the world, most intensively in the cities and megacities of the Americas. Public health concerns over the growing lead exposures in the Americas also developed quickly. In the Massachusetts Bay Colony of colonial America, the addition of lead to wine and cider was banned in the early eighteenth century, and concerns over lead in drinking water and the printing process were expressed by Benjamin Franklin, Charles Dana, and others (Wedeen, 1984). In the mid-nineteenth century, reports were published in Mexico of severe lead intoxication among ceramicists and those consuming food prepared in lead-glazed pots (Ruíz-Sandoval, 1878). In 1914, the dangers of lead-based paint for children were reported in the U.S. city of Baltimore, Maryland (Fee, 1990). These and other findings spurred several countries of the Americas, including Argentina, Chile, Cuba, Colombia, Mexico, Nicaragua, Panama, Suriname, Uruguay, and Venezuela, to sign the International Labour Organization's Agreement on Lead-Based Paint in the 1920s. The introduction of lead into gasoline in the 1920s was vigorously protested in the Americas by some leaders in occupational medicine. Nevertheless, effective actions to reduce lead use were not systematically undertaken in the hemisphere until the 1970s, largely because of the ability of the influential lead industry to control both scientific research and government policies in prior decades. Industry efforts and political indecision succeeded in preventing regulations on lead in gasoline, plumbing, paints, and canning for over 50 years, long after the hazards of these products and uses were known (EDF, 1992). It is now recognized, as summarized in the National Research Council report, Measuring Lead Exposures in Infants, Children, and Other Sensitive Populations (NRC, 1993), that lead is toxic to humans at very low levels (see Figure 3-2 in Chapter 3). As a basis for prevention, in 1991 the U.S. Centers

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

SETTING THE STAGE: HISTORICAL MILESTONES IN THE REDUCTION OF LEAD IN THE AMERICAS

43

Figure 2-1. Greenland ice evidence of hemispheric lead pollution two millenia ago by Greek and Roman civilizations. Source: Reprinted, with permission, from Hong, S., J.P. Candelone, C.C. Patterson, and C.F. Boutron, “Greenland ice evidence of hemispheric lead pollution two millennia ago by Greek and Roman civilizations,” Science 265(5180):1841-1843. ©1994 by the American Association for the Advancement of Science. Note: Fig. 2-1. (A) Changes in worldwide lead production over the past 5,500 years. (B and C) Changes in lead concentration and lead crustal enrichment factor in central Greenland ice from 2,960 to 470 years ago. Each data point was obtained from the analysis of a core length corresponding to exactly two years of ice accumulation (except one, for which it was only 1 year because of poor core quality) to eliminate the influence of possible short-term (seasonal) changes in lead deposition.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

SETTING THE STAGE: HISTORICAL MILESTONES IN THE REDUCTION OF LEAD IN THE AMERICAS

44

for Disease Control and Prevention (CDC) defined a blood lead concentration in excess of 10 µg/dl as a cause for concern (CDC, 1991). CDC's finding was based on extensive epidemiologic studies and basic research that consistently demonstrated adverse health effects of lead—at and above these levels of exposure—on cardiovascular function in adults and neurobehavioral and cognitive attainment in children. Lead intake also damages the kidney and liver and adversely affects reproduction. Despite the progressive lowering of the threshold of safety over the past 25 years, a historical perspective on lead toxicity, as shown in Figure 2-2, suggests that the question of whether there is indeed a threshold, or “safe,” level of lead exposure is largely irrelevant in the context of global contamination, which has resulted in blood lead levels in even remote populations that are over 100 times those of our preindustrialized ancestors (Silbergeld, 1995).

Figure 2-2. How Low is Toxic? Lead in perspective: blood lead levels in various populations and safety thresholds. Source: Silbergeld, E.K., “The international dimensions of lead exposure,” Intl J Occ and Envir Hlth 1:336-348, 1995. Reprinted with permission. Note: the LD50 for lead in children (100 µg/dl) is estimated from reports in the older clinical literature, although it is likely to be quite variable, depending upon the duration of exposure and the age of the child (Silbergeld, 1995). the CDC level of concern, 10 µg/dl, was set in 1991 (CDC, 1991). The median blood lead level for the U.S. population in 1990 was estimated to be 5 µg/dl (Brody et al., 1994). The lowest blood lead levels commonly found in many recent studies are about 1 µg/dl (NRC, 1993). Data on remote biota have been published by Rabinowitz, Flegal, and others (NRC, 1993). Blood lead level in preindustrial humans, 0.01 µg/dl, was estimated from measurements in bone (Silbergeld, 1995).

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

SETTING THE STAGE: HISTORICAL MILESTONES IN THE REDUCTION OF LEAD IN THE AMERICAS

45

This relatively recent increase in internal dose makes it unlikely that humans, and other biota, have been able to adapt to an element with no known essential role in physiology. National actions to prevent lead exposures in most of the countries of the world have been slow in coming; as a result, lead production and use continue to expand. Recently, however, public health policy has been expanded to consider broader, internationally coordinated options for preventing lead poisoning. Broad global strategies have been identified in meetings of the Organization for Economic Cooperation and Development (OECD), United Nations Conference on Environment and Development (UNCED), and the Commission on Sustainable Development (CSD) (Silbergeld, 1995). It was recognized in many of these meetings that surveillance and data collection to assess the prevalence of lead poisoning internationally are critical to gain political momentum and recognition of lead as a public health problem. The Earth Summit Watch, formed in preparation for the United Nations Conference on Environment and Development in 1992, consists of a group of nongovernmental organizations interested in conducting country-bycountry surveys of specific indicators of environmental problems. The Earth Summit Watch Survey Team, in 1993 and 1994, asked countries to indicate what they had done to address specific environmental issues, including lead exposure, and then made their survey results available in the report Four in ‘94 (NRDC and CAPE 21, 1994). The report is intended to help officially monitor govemment performance in programs designed and implemented to limit environmental degradation. Strategies directed toward lead exposure reduction within the region of the Americas have also been identified. In 1994, the U.S.-based nonprofit organization, the Alliance to End Childhood Lead Poisoning, hosted the first international conference to focus specifically on prevention of lead poisoning. The major goal of the conference, Global Dimensions of Lead Poisoning, was to increase international awareness of the causes and adverse effects of lead poisoning and to promote international collaboration in developing and implementing permanent, workable solutions and policies for prevention. Immediately following the conference, the United Nations Commission on Sustainable Development (CSD), established by the General Assembly in 1993, passed a resolution emphasizing the seriousness of lead poisoning as a public health problem. The end of 1994 saw the Summit of the Americas, which was convened in December in Miami, Florida, and attended by 34 heads of state from the

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

SETTING THE STAGE: HISTORICAL MILESTONES IN THE REDUCTION OF LEAD IN THE AMERICAS

46

hemisphere. At the summit, all heads of state agreed to the phase-out of leaded gasoline in the hemisphere. In March 1995, the U.S. Environmental Protection Agency and the Mexican Ministry of Environment, Natural Resources, and Fisheries cohosted the International Workshop on Phasing Lead Out of Gasoline to discuss the feasibility and logistics of phasing out leaded gasoline in countries that had not yet done so. The workshop concluded with a request to the CSD that it formally adopt a resolutiori to phase out leaded gasoline. After a lengthy debate, the CSD honored this request in May 1995. It was against this backdrop of increasing regional activity that the U.S. Institute of Medicine and the National Institute of Public Health of Mexico conducted the conference summarized in this report. This activity was designed to build on the work of these previous efforts by: (1) focusing on the multiple major sources of lead exposures in the Americas and (2) convening a broad range of interested and affected parties to generate specific action steps to reduce lead toxicity across the region, and to do so in ways that may be broadly accepted and costeffective.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

47

CHAPTER 3

Plenary Sessions

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

48

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

49

SESSION A

Keynote Address

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

50

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

LEAD AT THE WORKPLACE AND IN THE ENVIRONMENT: IS IT PREVENTABLE?

51

LEAD AT THE WORKPLACE AND IN THE ENVIRONMENT: IS IT PREVENTABLE?

JORMA RANTANEN*

Although International Labour Organization Convention No. 13 on White Lead prohibited the use of lead paint as early as 1921 (ILO, 1921), lead paints continue to contribute to thousands of acute lead poisonings annually and to chronic lead effects in individuals in both industrialized and developing countries. As shown in Table 3-1, emissions of lead into air, water, and soil are higher than those of any other toxic metal, and the mobilization of toxic metals into the environment exceeds the total toxic burden of all radioactive and organic waste (Nriagu and Pacyna, 1988). There is convincing evidence, however, that the total annual consumption of about 8.9 million tons of newly mined lead, as well as similar amounts of recycled lead, could be substantially reduced at relatively little economic cost, and that present technologies and multisectoral preventive actions could, in a relatively short time and in an economically feasible manner, effect a remarkable reduction in both environmental and occupational exposures. TABLE 3-1 Toxic metal

Water 106 kg/yr−1

Soil 106 kg/yr−1

Air 106 kg/yr−1

As

12–70

64–132

12–25.6

Cd

2.1–17

9.9–45

3.1–12

Cr

45–239

—

7.3–53.6

Hg

0.3–8.8

2.2–18

0.9–6.2

Ni

33–194

160–673

24–87

Pb

97–180

808–1,893

289–376

V

2.1–21

48–242

30–142

Zn

77–375

1,193–3,294

70–194

Source: Adapted from Nriagu and Pacyna, 1988.

* Finnish Institute of Occupational Health, Helsinki, Finland

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

LEAD AT THE WORKPLACE AND IN THE ENVIRONMENT: IS IT PREVENTABLE?

52

There are several obstacles in the way of such preventive programs. These include a lack of awareness of the magnitude and severity of lead poisoning in most of the populations of the world, short-sighted economic objectives, and poor local availability of expertise and technologies in support of prevention and control activities. MANAGEMENT OF LEAD HAZARDS IN AN INDUSTRIALIZED COUNTRY-THE CASE OF FINLAND The Finnish Lead Program began in the 1960s with the implementation of systematic diagnosis and treatment of lead-poisoned workers from the battery industries, metal foundries, metal scrapping concerns, and dockyards. Intensive studies of lead poisoning in the Finnish population began with a focus on hematological effects, clinical symptoms, and blood lead concentrations in occupationally exposed workers. The value of δ-aminolevulinic acid dehydratase (ALA-D) as an indicator of lead exposure was quickly recognized. As a result, studies were expanded to detect early biologic effects of lead exposure, including neurologic, psychologic, cardiovascular, reproductive, and carcinogenic effects. The findings of these studies were considered in the World Health Organization's recommendations on health-based exposure limits (WHO, 1977) and helped in the development of a field-feasible test battery of psychometric effects of lead poisoning. As a result of the growing evidentiary base linking occupational lead exposures to adverse health outcomes, guidance values for biological monitoring and guidelines for health surveillance of workers potentially exposed were established in Finland (Hernberg, 1995). Further preventive actions included setting a lower exposure limit for workroom air (0.1 mg/m3), using nonlead technologies where possible, implementing local exhausts and dust control, introducing safer work practices, and promoting careful personal protection. The impact of these actions can be seen in the decline of the numbers of workers exposed to lead and the decreasing proportion of workers exceeding threshold blood lead levels of 2.4 µmol/L (see Figure 3-1). The environmental lead exposure plan developed in Finland originated, in part, with the industry sector, which substantially reduced their emissions

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

LEAD AT THE WORKPLACE AND IN THE ENVIRONMENT: IS IT PREVENTABLE?

53

in water (60 percent decrease between 1980 and 1989) and in air (16 percent decrease between 1987 and 1990) in Finland. Once industries began controlling their lead emissions, automotive traffic ended up contributing 75 percent of environmental lead emissions. Thanks to the introduction of unleaded gasoline in the mid-1980s, vehicular emissions to air have now fallen by 88 percent. As a result, lead emissions in urban air in Finland are virtually zero at present. Since only about five industries are now responsible for 99 percent of the industrial lead emissions, the possibility for further reduction in environmental lead burden is excellent.

Figure 3-1. Blood lead level monitoring measurements, 1973-1994, Biomonitoring Laboratory, Finnish Institute of Occupational Health. Source: Valkonen, 1995. MANAGEMENT OF LEAD HAZARDS IN THE WORKPLACE OF DEVELOPING AND NEWLY INDUSTRIALIZED COUNTRIES Although systematic data, particularly on lead exposures in the developing world, are not widely available, there is sporadic evidence that suggests both a high prevalence and intensity of lead-related health problems in developing and newly industrialized countries. There is thus a need for systemic and

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

LEAD AT THE WORKPLACE AND IN THE ENVIRONMENT: IS IT PREVENTABLE?

54

representative surveys of environmental lead exposures, as well as biological monitoring of individual lead exposures. Lead surveys were elements of Finnish development aid programs from the beginning. In the early 1980s, for example, a lead survey was carried out in Kenyan battery industries. Results indicated unexpectedly high blood lead levels among battery workers, but also among the canteen and office personnel, thus indicating a widespread, indirect contamination of the work environment (Kurppa et al., 1985). An interesting, but not well-established, observation was that lead-related clinical symptoms manifested at lower blood lead levels among malarious individuals than among people without malaria. Disappointingly, while general hygienic measures reduced the exposures of the office and canteen personnel, they had little effect on production line workers, who maintained high blood lead levels. The authors concluded that preventive measures appeared to have little effect because of the low level of awareness of the dangers of lead poisoning in these workers. The risk of lead exposure on the job is a worldwide problem. A systematic survey of workers in four Asian countries showed that approximately 30 percent of the workers surveyed had elevated blood lead levels (Chia and Koh, 1992; Phoon et al., 1985), and some Central and Eastern European countries report elevated levels in up to 100 percent of the workers tested (Cikrt, 1990; Kaloyanova, 1991). These examples demonstrate clearly that lead poisoning remains a major occupational health and environmental problem in many parts of the world, despite the availability of relatively simple preventive educational and control measures that could bring about a clear reduction in exposures and in adverse health effects in most of these populations in a relatively short time. WHAT IS THE ROLE OF RESEARCH IN THE MANAGEMENT OF LEAD HAZARDS? The Finnish Lead Program was instituted because of research findings indicating high blood lead levels in exposed workers; our preventive actions have been similarly supported by research data. Our activities in developing countries have been strongly oriented toward risk surveys to estimate population lead burden and sources of exposure. Our assessments of health risk and methods for exposure detection and measurements of early effects have been based on decades of research effort. On the basis of these experiences, the question—how much and what kind of research

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

LEAD AT THE WORKPLACE AND IN THE ENVIRONMENT: IS IT PREVENTABLE?

55

(if any) is needed to identify, control, and prevent lead hazards in developing countries—can be posed. Our experience demonstrates that several kinds of research efforts are needed to identify and prevent lead poisoning. These include: • surveys of environmental lead levels and sources of exposure; • research on body lead screening methods to ensure accuracy and reliability; • surveys of lead levels in selected representative samples of the general population, with particular focus on identification of high-risk groups; • monitoring of health effects in lead-poisoned populations; • evaluation of feasibility and effectiveness of proposed preventive and control activities; • evaluation of the effectiveness of ongoing prevention and control activities; • setting of appropriate standards to ensure occupational and environmental safety and health. Two points should be stressed in undertaking the above research activities. First, these activities should not displace current interventions to reduce lead exposures. Second, research activities must be developed and conducted at the local level by regional or local scientists and health providers representing a broad range of expertise and perspective. SUSTAINABLE PREVENTION OF LEAD POISONING Control of lead exposure requires preventive measures at the global, national, and local levels. In developing countries, identification of lead problems has, in most instances, brought effective preventive measures and regulatory actions (East African Regional Programme on Occupational Health and Safety, 1991). Often, simple precautions such as adding ventilation and local exhausts, or health education, have brought about dramatic reductions in blood lead levels. The Finnish Lead Program has developed a wealth of data and experience on the detection of occupational lead poisoning and effective strategies for prevention and control. Based on our experience, the list of preventive actions that we recommend to national, regional, and local decisionmakers and other involved parties are:

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

LEAD AT THE WORKPLACE AND IN THE ENVIRONMENT: IS IT PREVENTABLE?

56

• Survey the national, regional, and local situations and identify the activities and population groups at highest risk of lead exposure. • Raise public awareness, motivation, and knowledge of the sources and dangers of lead poisoning through educational campaigns that are both broadly directed and targeted to high-risk groups. • Encourage the adoption of lead-free technologies where possible. • Set stringent standards—for example, 0.1 mg/m3 of respirable lead-containing dust for workers and a ceiling of 40 µg/dl for blood lead levels in occupationally exposed workers—and ensure their enforcement. • Introduce hygienic work practices in high-risk work environments and make personal protectors available. • Monitor work environments and workers to identify exposed individuals and assess the effect of preventive and control measures. • Examine the health of lead-exposed workers periodically. • Educate workers about hygienic habits and other behaviors in lead-contaminated environments—for example, cigarette smoking—that may increase risk of lead ingestion or inhalation and poisoning.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

57

SESSION B

Health Effects of Lead

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

58

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EFFECTS OF LEAD ON CHILDREN'S HEALTH

59

EFFECTS OF LEAD ON CHILDREN'S HEALTH

EDUARDO PALAZUELOS-RENDÓN*

SOURCES AND PATHWAYS OF LEAD POISONING IN CHILDREN The use of lead dates back some 7,000 years in such activities as mining, pottery, glasswork, and the production of cosmetics. Its use has broadened in modern times and now extends to the production of paints and the chemical, petroleum refinery, and automotive industries. Unfortunately, lead is also an element that serves no vital function in the human organism and is one that is toxic, even in the smallest amounts. Humans have utilized lead in such abundance and for so long that levels of lead have been found in minuscule amounts in almost all populations surveyed. This, sadly, has made it possible to talk about a “normal” lead level in humans. Sources of lead exposure in humans can be classified into two groups, according to the population affected. One source derives from occupational and industrial sources and the other from “domestic” sources, where the target population includes nonworking adults and children, and the exposure levels are influenced by the environment, customs, and habits of that population. Control and prevention strategies to address domestic sources of lead exposure are more complex than those for confined occupational sources, because of the former's varied, heterogeneous nature (Landrigan, 1988). The major domestic sources contributing to increased blood lead levels in children in most countries of the Americas are vehicular traffic and air pollution caused by use of leaded gasoline (Romieu et al., 1992). Other important sources include use of earthenware that contains lead, leaded paint in residential housing, and consumption of water from pipelines and food stored in tin cans that contain leaded solder (Hernberg, 1975;

* Minister of the Environment, Mexico City, Mexico

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EFFECTS OF LEAD ON CHILDREN'S HEALTH

60

Jiménez et al., 1993; Lara-Flores et al., 1989; Schwartz and Levin, 1991; Tackett, 1987). Indirect exposures to lead hazards are also probably common to children in many countries of the Americas. In Mexico City, for example, a case of indirect lead poisoning was reported in a clinical session at the Hospital Infantil de México Federico Gómez in April 1995. The case, a 3-year-old child of low socioeconomic status from a rural community, was admitted with neuroencephalopathy and convulsions of 24 hours duration and with a history of eight days of vomiting not related to food or liquid consumption. The patient died five days after admission without a diagnosis. The only relevant information in the patient's history that indicated potential lead exposure was that the child was the daughter of potters. The diagnosis of acute lead poisoning was made by autopsy. This is a rare and extreme event associated with lead poisoning and illustrates the lack of awareness that lead is an important public health problem. The major pathway of exposure in children is through the digestive system. Young children characteristically explore their environment with their hands and mouths and, as a result, many children consume items not normally eaten, such as leaded paint chips, a behavior called pica (Barltrop and Khoo, 1975; Johnson and Tenuta, 1979). In addition, children absorb lead at a higher rate than adults: children absorb about 50 percent of the lead in their diets; adults have an absorption rate of approximately 5 to 10 percent (Mahaffey, 1981). The total amount of lead consumed can also influence absorption rates in children. Mahaffey (1981) has shown, for example, that when the amount of lead in the diet is greater than 5 mg/kg of body weight, children absorb and retain relatively more lead. The sources of lead ingested by children differ according to the time, region, and group of children studied. For example, principal sources of lead poisoning in children were reported to include ingested household dust contaminated with lead brought home by parents who are industrial workers in Memphis, Tennessee (Baker et al., 1977); contaminated soil in an area near a lead smelter in Santo Amaro, Brazil (Silvany-Neto et al., 1989); household leaded paints and lead-containing tap water in Boston, Massachusetts (Shannon and Graef, 1992); and contaminated dust from factories producing lead-containing ceramics in the Umbria region of central Italy (Abbritti et al., 1992). Research has shown that the consumption of certain nutrients in the diet—including minerals such as calcium, phosphorus, iron, and zinc and vitamins such as vitamins C, E, and thiamin—can reduce absorption of dietary lead in children (Mahaffey, 1990). Nutrition education directed

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EFFECTS OF LEAD ON CHILDREN'S HEALTH

61

toward increasing the levels of these nutrients in the diet may, therefore, be a useful intervention in situations where dietary lead levels are characteristically low. EVOLUTION IN CLINICAL UNDERSTANDING OF THE DANGERS OF LEAD POISONING IN CHILDREN The evolution in clinical understanding of the dangers of lead toxicity in children had two defining moments. The first occurred at the end of the nineteenth century with the recognition that lead is a poison. This understanding derived from a clinical case series of children with high blood lead levels in Australia who exhibited concomitant symptoms of paralysis and opthalmoplegia (Needleman, 1988, 1992b). Prevention and control strategies, in response, focused on rapid identification of exposed populations (primarily industrial), description of the sources of poisoning, and attempts to reduce the acute effects of intoxication. Following this report, the orientation of public health interventions was directed toward study and control of severe lead poisoning and its associated health effects, including plumbic colic, encephalopathy, anemia, and renal illness. The more subtle adverse effects now known to be associated with lower exposure levels remained unrecognized until more recently (Goyer, 1990). The second phase was initiated in the 1960s with the development of biologic markers for low exposure levels and clinical identification of associated adverse health effects. These advancements changed the clinical and public health paradigm of lead poisoning to one of widespread acceptance that no level of lead exposure could be considered safe. Figure 3-2 reflects current understanding of the adverse health affects associated with increasing blood lead levels. The growing recognition of lead's dangerous effects has led to a gradual reduction in acceptable blood lead levels. In 1960, for example, the acceptable limit was 60 µg/dl; limits subsequently dropped, to 40 µg/dl in 1971 and 30 µg/dl in 1975. By 1985, the limit in Mexico was lowered to 25 µg/dl; by 1990, the highest acceptable level of lead in blood was 15 µg/dl. Accumulating epidemiologic data now convincingly demonstrate neurotoxicity in children exposed to lead at levels below 15 µg/dl and, as a result, the U.S. Centers for Disease Control and Prevention (CDC) have now lowered their acceptable blood lead limit to 10 µg/dl (CDC, 1991). The decline in acceptable levels was prompted, in large part, by the increasing sophistication of screening methods. Biologic markers that

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EFFECTS OF LEAD ON CHILDREN'S HEALTH 62

Figure 3-2. Effects of inorganic lead on children and adults—lowest observable adverse health effects. Source: ATSDR, 1992.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EFFECTS OF LEAD ON CHILDREN'S HEALTH

63

have been used in surveys of children include lead in blood, teeth, hair, and bone. Blood lead is the most commonly used indicator, and it has been the basis for most of the studies that have established cause-and-effect relationships between lead exposure and disease. The level of lead in blood reflects, biokinetically, both the degree of relatively recent exposure to lead and the toxicologically active fraction of the total body load of lead in various tissues, at least in stable conditions. Blood lead levels are more labile in childhood and tend to become more stable with age. Values of lead in hair, teeth, and bone provide a measure of accumulated exposure over time. Of the three, lead in hair represents perhaps the most useful biologic indicator because its samples are noninvasive, can be stored indefinitely, and can provide temporal clues to exposure through sampling across the length of the hairshaft. SYMPTOMS AND SIGNS OF SEVERE LEAD POISONING IN CHILDREN In children without encephalopathy, lead poisoning is characterized by one or more of the following symptoms: reduction in play activity, lethargy, anorexia, sporadic vomiting, intermittent abdominal pain, and constipation. In cases of acute lead poisoning, encephalopathy may present at diagnosis with the following symptoms: coma, convulsions, behavioral disturbances, apathy, lack of coordination, vomiting, alteration in consciousness, and loss of recently learned abilities (Piomelli et al., 1984). Studies of lead-induced encephalopathy indicate that blood lead levels must be very high (90 to 400 µg/dl) to produce clinical signs of encephalopathy such as hyperactivity, ataxia, convulsions, stupor, and coma. Blood lead levels of 60 to 300 µg/dl may produce encephalopathic-like signs and symptoms that are often confused with true encephalopathy (Grant and Davis, 1989). In recent years, researchers have reported extensive results on the developmental and neuropsychological effects of lead in children (Needleman and Gasonis, 1990; Pocock et al., 1987). Lead is a neurotoxic that adversely affects neurodevelopment of children. Groups of children at high risk of lead exposure have been shown to have lower intelligence scores, depending on the type of evaluative test used. Although these findings continue to be challenged by an increasing minority of clinicians and researchers, there is a rapidly accumulating base of evidence that suggests that blood lead levels are inversely related to cognitive function and ability (Bentou-Maranditou et al., 1988; Hansen et al., 1989; Landrigan, 1989; Needleman and Gatsonis, 1990; NRC, 1993;

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EFFECTS OF LEAD ON CHILDREN'S HEALTH

64

Rabinowitz et al., 1991). Studies have also indicated inverse associations between body lead levels and neuroconductivity (Fergusson et al., 1993; Grandjean et al., 1991; Stiles and Bellinger, 1993), motor-visual integration (Baghurst et al., 1995; Bellinger, 1995), and behavioral problems reported by teachers and parents (Silva et al., 1988). In 1993, Muñoz and colleagues (1993) reported findings of a study evaluating neurocognitive development capacity in children in Mexico City with chronic lead exposures. Their results showed that the average blood lead levels of their study sample exceeded 19 µg/dl and that the major sources of exposure were vehicular traffic near the child's residence, use of glazed pots for preparing or storing food or juices, and frequency of chewing pencils. Blood lead levels were a strong predictor of lower performance on full-scale IQ as measured by a version of the Wescheler Intelligence Scale for Children (WISC), as well as lower scores on other measures of school performance. Studies of prenatal blood lead levels as predictors of future neurologic and behavioral development of the fetus and child are of increasing interest. One of the elements that has permitted this line of research is the ability to evaluate fetal exposure to lead through measurements of the umbilical cord blood and bone lead of the mother. For example, Bellinger and colleagues (1984, 1986) reported neurobehavioral deficits on the Bayley Scale of Infant Development associated with higher prenatal exposures (cord blood lead levels of 10–25 µg/dl). The observed deficits persisted until two years of age, although postnatal exposures of all children in the study cohort were comparable. Further study of these children suggested that the neurobehavioral differences associated with the high cord blood levels were strongly attenuated by the time the children reached preschool age (Bellinger, 1991). Values obtained from such indicators of early exposure from cord blood levels will provide a basis for many ongoing cohort studies evaluating early lead exposure and neurologic outcome. Autopsy studies indicate that bone is the primary site of storage for about 95 percent of lead in the human body. It is known that pregnancy and lactation create a significant demand for calcium and that this calcium is, in part, provided from bone, a process that causes the concomitant release of accumulated lead. Studies that incorporate consideration of blood lead levels as a source of exposure will thus increase the ability to assess the deleterious effects of maternal lead burden in the newborn.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EFFECTS OF LEAD ON CHILDREN'S HEALTH

65

CONCLUSIONS Children continue to be exposed to lead across the Americas, although the sources and pathways of exposure differ across and within countries. In Mexico, as in many other countries of the region, a major hurdle remains the need to convince the health authorities of the extent and seriousness of childhood lead poisoning. To move toward this end, there is a need for more extensive identification and monitoring of lead levels in high-risk children and for the strengthening of medical education to alert pediatricians and other clinical practitioners to the signs, symptoms, and effects of lead poisoning. Blood lead levels should be measured at least once in high-risk children in the first year of life, and clinic personnel should be prepared to provide basic counseling to parents on how to reduce infant and child exposure to lead. Special attention should be directed toward reducing domestic sources of exposure—for example, through education about the dangers of using leaded ceramics in food preparation and storage.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EFFECTS OF LEAD ON ADULT HEALTH

66

EFFECTS OF LEAD ON ADULT HEALTH

JULIETA RODRÍGUEZ DE VILLAMIL*

Lead poisoning continues to be one of the most prevalent occupational, paraoccupational, and environmental illnesses affecting adults. No metal has been more extensively studied from the epidemiologic, clinical, and toxicologic perspectives (see Saryan and Zenz, 1994). Unfortunately, clinical diagnosis of lead poisoning in the adult is often complicated by the variability and indistinctiveness of the presenting symptoms and signs. Correct diagnosis of a lead-poisoned individual, therefore, requires adequate clinical training, the execution of a complete occupational and environmental history, laboratory facilities for lead determination, and awareness of the problem by health care professionals. An understanding of the problem of lead poisoning in adults requires that specific factors that predispose or aggravate lead's effects be taken into account. Examples of such factors are: • • • • • •

the concentration and type of lead (inorganic lead vs. alkyl lead) in the source of exposure; the duration of exposure; the route of entrance into the adult; the underlying nutritional status and health of the individual; the age of the individual exposed; the health-related habits/behaviors of the person exposed (for example, cigarette smoking in a contaminated environment); • the race and sex of the person exposed. The combination of these factors will influence the susceptibility of the exposed person and the nature and extent of his or her disease. It will also influence the choice of strategies to best prevent or control a given environmental or occupational exposure.

* Under-Minister of Occupational Health, Bogota, Colombia

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EFFECTS OF LEAD ON ADULT HEALTH

67

RECOGNITION OF THE PROBLEMA By the time that Hippocrates first described symptoms of lead poisoning in metal workers, physicians were aware of the lethal effects of inhaling lead fumes and methods of protection for workers. At that point, however, the Romans used lead widely for cosmetics, wine reservoirs, and construction of aqueducts and cisterns (Kazantzis, 1989). In the early twentieth century, Alice Hamilton described symptoms of lead poisoning in painters and other artisans whose paints were lead-based (Hamilton and Hardy, 1949). This was followed by a growing number of monographs, worldwide, that described similar symptoms and signs in other occupational groups exposed to lead. ROUTES OF EXPOSURE The major routes of absorption of lead are the gastrointestinal tract and the respiratory system. Skin absorption of lead is generally insignificant; when lead is in the form of lead alkyl compounds (such as tetraethyl lead), however, it can be absorbed readily by the skin. Once lead particulates are deposited in the lower respiratory tract, they are rapidly and completely absorbed. The rate of deposition varies according to the particulate size and the ventilation rate. As a rule, in the adult, between 30 and 50 percent of lead is absorbed. Lead ingestion also results from consuming food and beverages contaminated with lead and from swallowing lead particulates cleared by the upper respiratory tract. The absorption of lead by the gastrointestinal tract appears to be low in adults, but not in children, as is indicated in the previous report by Dr. Eduardo Palazuelos-Rendón. Gastrointestinal absorption is increased by dietary deficiencies of calcium, iron, potassium, and zinc. For the forms of lead in the normal diet, absorption is also increased by fasting. Absorption rates can vary from a high of 45 percent in fasting conditions to a low of 6 percent in the presence of food. Lead, whether absorbed through the gastrointestinal tract or the respiratory system, is distributed in essentially the same fashion into blood, bone, and soft tissues. Figure 3-3 depicts the metabolism of lead in the human system. Blood lead is the biological marker most commonly used to assess lead exposure. Approximately 3 percent of the total body burden of lead circulates in the blood. Within the circulatory system, the majority of

Copyright © 1996. National Academies Press. All rights reserved.

Figure 3-3. Simplified model of the metabolism of lead in man. Source: Hernberg, 1988.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EFFECTS OF LEAD ON ADULT HEALTH 68

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EFFECTS OF LEAD ON ADULT HEALTH

69

lead (around 50 percent) is associated with hemoglobin, and only a small and variable fraction (depending on a nonlinear relation to the whole blood lead level) is free in plasma. This biologically active fraction of lead—which is able to cross the placental and hematoencephalic barriers—is considered to be the fraction that contributes to immediate toxicity. Lead in blood has the shortest half-life, estimated to be between 28 and 36 days, followed by lead in soft tissue (46 days), and lead in bone (20 years or more). Autopsy studies indicate that lead accumulates in bone throughout life. Bones serve as a long-term repository of approximately 75 percent and 95 percent of lead in children and adults, respectively (Barry and Mossman, 1970). Studies have demonstrated that bone lead levels remain elevated despite declines in blood lead, suggesting that bone lead may be a better biological marker of chronic toxicity (Steenhout, 1982). Indirect evidence has shown that lead is continually released from bone stores, but particularly so during times of increased bone turnover such as pregnancy, breastfeeding, and menopause (Silbergeld, 1991). Therefore, as indicated in the previous paper by Dr. Eduardo Palazuelos-Rendón, there is concern that—in addition to affecting the adult woman—a significant amount of bone lead may be transferred to the fetus or to the breastfed infant. EXCRETION Data suggest that in adults constantly exposed to lead, between 50 and 60 percent of the absorbed fraction of lead is excreted within 15 days. Excretion occurs predominantly through urine and, in minor quantities, through bile and exfoliation of epithelial tissue. HEALTH EFFECTS Hematopoetic Effects Lead has long been known to affect heme biosynthesis by inhibiting the δ-aminolevulinic acid dehydratase (ALA-D). Microcytic anemia is one of the early manifestations of lead poisoning—abnormalities in the peripheral blood smear include microcytes with stippling Cabot's rings. In occupationally exposed adults, however, the blood lead threshold level for a decrease in hemoglobin is estimated to be 50 µg/dl.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EFFECTS OF LEAD ON ADULT HEALTH

70

Neurological Effects on the Central and Peripheral Nervous Systems Acute encephalopathy is commonly seen when ambient air concentrations of lead are higher than 10 mg/m3 and when blood lead levels exceed 100 µg/dl. Chronic encephalopathies associated with lower levels of lead exposure are characterized by changes in mental activity and cognitive function, hyperirritability, disassociation, depression, and headaches, while higher blood lead levels have been associated with vertigo, ataxia, convulsions, explosive vomiting, and stupor. Severe sequelae include blindness, mental retardation, mental dysfunction, epilepsy, neurobehavioral disruptions, coma, and death. Peripheral neuropathy—characterized by cutaneous hypersensitivity, tremors, weakness, hypotonia, and muscular atrophy—has been associated with lead exposure, although a clear dose-response relationship has not been demonstrated. Compromised radial nerve function and “horse foot” (compromised fibula nerve function) have also been frequently described in lead poisoning victims. Subclinical states have also been described in asymptomatic adults with lead levels between 80-120 µg/dl and have been characterized by diminished conductor velocity, muscular fibrillation, and loss of motor neurons. Renal Effects Acute renal effects include reversible loss of renal function—damage to the proximal tubules, which produces a Fanconi Syndrome manifested by aminoaciduria, glucosuria, and phosphaturia. Continuous, prolonged high lead exposure results in chronic and nonreversible effects associated with progressive interstitial fibrosis, which may lead to renal damage characterized by interstitial fibrosis, sclerosis of vessels, glomerular atrophy, reduced glomerular filtration, and azotemia. Cardiovascular Effects There is considerable debate as to whether there is a causal association between lead exposure and hypertension (Hertz-Picciotto and Croft, 1993). Large-scale mortality studies of occupationally exposed individuals have strongly supported the association between lead and hypertension. Schwartz estimated that in the United States, 24,000 cases of myocardial infarction yearly could be eliminated if blood lead levels were reduced by 50 percent

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EFFECTS OF LEAD ON ADULT HEALTH

71

(Schwartz, 1991). In contrast, most studies in the general population have reported small effects on blood pressure, or no association at all. Taken together, the evidence does not provide conclusive evidence that lead exposure is positively associated with hypertension. More studies are needed, especially longitudinal studies that use new biomarkers for cumulative exposure, and serial measurements to evaluate recent exposure. Gastrointestinal Effects Colic is a consistent early symptom in occupationally exposed cases or in cases of acute intoxication. Initial nonspecific symptoms appear at blood lead levels of approximately 80 µg/dl, and include dyspepsia, anorexia, postprandial epigastritis, constipation, cramps, and nausea. Gastrointestinal symptoms are aggravated when blood lead levels reach 100 µg/dl or higher and can include severe abdominal colic and constipation. Severe symptoms occur at blood lead levels of 150 µg/dl or higher and can include “lead colic” (severe abdominal spasms that resemble acute abdominal pain requiring surgery) and liver damage. Skeletal Effects Formation of lead triphosphate binds lead to bone. This “hidden” accumulation is released during the demineralization of bone that occurs in the normal metabolic processes of aging and pregnancy. The release of “hidden” lead during pregnancy and that unbound lead is present in mother's milk is of particular concern given the increased risks this poses to the fetus and infant. Reproductive Effects A large number of reports indicate that high levels of lead exposure are associated with impaired fertility in both women and men (Rom, 1976). Several studies have reported an increase in miscarriage, stillbirth, low birthweight, and other abnormalities associated with high exposures at industrial levels. Low-level exposure in utero has been associated with higher prevalence of low birthweight, reduced head circumference, and reduced length at birth (Coste et al., 1991; Lancrajan, 1975).

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EFFECTS OF LEAD ON ADULT HEALTH

72

Carcinogenic and Genotoxic Effects Other effects related to lead exposure include genotoxic and carcinogenic effects. Data suggest that exposure to organic lead can result in changes in lymphocyte chromosomes. In relation to carcinogenic effects, lead byproducts, including phosphate and lead acetate, are known to cause renal cancer in laboratory animals, although this has not been proven in humans. EXPOSURE INDICATORS Plumbism (although there are no associated pathogenic signs and symptoms) can be used as an indicator of recent exposure, although symptoms and signs are often vague and nonspecific. Levels of lead in urine exceeding 150 µg/dl can be diagnostic of lead poisoning. Blood levels of erythrocyte protoporphyrin (ZPP) correlate well with lead exposure and provide a useful indicator for general population screening, but can be inaccurate in cases of iron deficiency. Levels of ZPP and their blood lead equivalents are presented in Table 3-2. Clinical Tests Lead can be measured in blood, serum, urine, tissues, teeth, bone, and hair. All of these indicators provide reliable information about exposures and health risks associated with exposure. Tests that are useful in the diagnosis of lead poisoning are: TABLE 3-2 ZPP (mg/100 ml)

Interpretation

Blood Lead Level Equivalents

< 80

Normal for adults

—

80–250

Typical labor exposure

20–40 mg/100ml

251–500

High range of exposure

40–55

> 500

Extreme exposure

> 55

Source: Adapted from Saryan and Zenz, 1994.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EFFECTS OF LEAD ON ADULT HEALTH

• • • • •

73

ALA-D:

Normal levels in urine are 6 µg/dl. This test has limited utility because of its high cost. Urinary coproporphyrin >500 µg/dl. Electrophysiological tests of conduction velocity, evoked potential. Tests of neuroconductivity. These are of particular use in evaluating children. Radiological exams of long bones (lead line) and abdomen (for radiopaque paint), and, recently, X-Ray Fluorescence, have been found useful in determining levels of sequestered lead in bone. Clinical Examination

Clinical examination of cases of suspected lead poisoning should include a detailed history of possible environmental and occupational exposure to lead; a complete physical examination, especially of blood pressure; laboratory tests of blood lead, hematic cytology, hemoglobin, BUN, and creatine; and urinalysis. Treatment The first step in treatment must be to identify the source of patient exposure, to identify other family members or coworkers with a similar exposure, and to intervene immediately to stop exposure. Vomiting should be induced in cases of recent lead ingestion; the use of coal, other carbon, or cathartics is not of proven efficacy. Symptomatic treatment should be applied in cases of encephalopathy. The use of chelation therapy with such agents as calcium disodium edetate (EDTA), British antilewisite (BAL), d-penicillamine (DMPS), and/or succimer (DMSA) Can be useful in cases of severe lead poisoning. The cost of these therapies is high, however, and use of these agents has associated undesirable side effects (Frumkin, in press). CONCLUSIONS The multisystemic effects, prolonged half-life in the human organism, and chronicity of lead poisoning underscore its seriousness as a public health problem and illustrate the need to focus public health attention on prevention as a first priority. Lead is ubiquitous in the environment. As a result, detection, prevention, and control strategies need to be directed to domestic as well as

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

EFFECTS OF LEAD ON ADULT HEALTH 74

occupational sources. The responsibility of controlling lead exposures and guaranteeing healthy working and living conditions must be shared by everyone, including government, workers, unions, scientists, health providers, and the general public.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

75

SESSION C

Extent, Sources, and Pathways of Lead Exposure in the Hemisphere

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

76

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

PREVALENCE OF EXPOSURE AND DATA QUALITY OF LEAD CONTAMINATION IN LATIN AMERICA AND THE CARIBBEAN

77

PREVALENCE OF EXPOSURE AND DATA QUALITY OF LEAD CONTAMINATION IN LATIN AMERICA AND THE CARIBBEAN ISABELLE ROMIEU/MARINA LACASANA*

The rapid industrial development that the American region has experienced has brought an accumulation of distinct, potentially toxic elements—of which lead is one—into the environment. We have compiled existing information on the magnitude of the problem in Latin America and the Caribbean in order to evaluate: (1) the major sources of exposure to lead in the region, (2) the impact of this exposure as measured by blood lead levels on specific population groups, and (3) the effectiveness of actions by national governments to prevent and control lead exposure. These actions include legislation to protect the environment and occupationally exposed populations. METHODS A survey was undertaken with the help of national representatives of the Pan American Health Organization (PAHO). The survey requested information on: (1) production, export, and import of lead (tons/year); (2) industrial use of lead; (3) sources of lead emission in the air; (4) other principal sources of lead exposure; (5) measurement studies of lead in the environment; (6) results of studies that measured blood lead levels in specific populations; and (7) the nature of existing regulations and rules for the control of lead contamination. RESULTS Of the national PAHO representatives surveyed, 57 percent (16/28) responded. While the rate of Latin American countries answering the survey, excluding the Caribbean, was 83 percent (15/18 countries), the rate of response from the Caribbean Basin was only 30 percent (3/10 countries).

* Pan American Center for Human Ecology and Health, Metepec, Mexico

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

PREVALENCE OF EXPOSURE AND DATA QUALITY OF LEAD CONTAMINATION IN LATIN AMERICA AND THE CARIBBEAN

78

Latin America and the Caribbean contribute 14 percent of the world production of lead. Peru and Mexico are the leading producers in the hemisphere. In Latin America, the principal lead mines are located in Peru, Mexico, and Argentina; the primary smelters are in Peru, Mexico, Brazil, Argentina, and Nicaragua; and the secondary smelters are in Mexico, Brazil, Colombia, Venezuela, and Trinidad (see Figure 3-4). Several additional Latin American and Caribbean countries also produce lead or import it for industrial use. Lead, in different forms and compounds, is used in numerous industries and activities, but numbers and intensity of lead use are not well known in Latin America and the Caribbean. In countries such as Mexico, Peru, and Honduras, for example, lead varnishes are commonly used as glazes for ceramicware, although the extent of production and distribution of lead-glazed ceramicware is not precisely known. The survey data also suggest that for the majority of Latin American and Caribbean countries (excluding Brazil, Guatemala, and Mexico), one of the more important uses of lead is as an antiknocking agent in gasoline. In the last 14 years, however, the lead content in gasoline has actually been reduced in Bolivia, Brazil, Chile, Mexico, Guatemala, Uruguay, and Venezuela. Currently lead levels in gasoline vary from 4.99 grams a gallon (g/ gal) in Suriname to 0.70 g/gal in Argentina, Colombia, and E1 Salvador, and 0.19 g/gal in Mexico. According to the survey, 36 percent of the countries in the region that responded have introduced unleaded gasoline. These include Argentina, Bolivia, Brazil, Chile, Colombia, El Salvador, Mexico, Peru, Costa Rica, Guatemala, Honduras, and Uruguay in Latin America and the Dominican Republic and Trinidad in the Caribbean Basin. The survey also assessed the proportion of unleaded gasoline used for automotive purposes because this may provide a good indicator of the success of the national programs to reduce lead contamination of air. Of the countries responding to this question, Brazil, Guatemala, and Mexico reported the greatest proportion of unleaded gasoline used (100, 80, and 46 percent, respectively). They were followed by the Dominican Republic, Chile, Colombia, and Argentina, which reported proportions of 28.6, 13, 10, and 6 percent, respectively. The use of unleaded gasoline in Peru was reported to be minimal (0.2 percent). In other countries, including El Salvador, Costa Rica, and Honduras, information regarding the proportion of unleaded gasoline use was not reported. The estimates above provide the only measure, albeit an indirect one, of lead levels in air for most of the Latin American and Caribbean countries

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

PREVALENCE OF EXPOSURE AND DATA QUALITY OF LEAD CONTAMINATION IN LATIN AMERICA AND THE CARIBBEAN 79

Figure 3-4. Geographic distribution of major lead mines and smelters across the Americas. Source: Reprinted with permission from Arnold Bombay, AB Graphics.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

PREVALENCE OF EXPOSURE AND DATA QUALITY OF LEAD CONTAMINATION IN LATIN AMERICA AND THE CARIBBEAN

80

responding to the survey. The exceptions are Brazil and Mexico, which have recorded data on air pollutants, including lead. In Brazil, the “national program of alcohol” was initiated in 1975 to bring to the forefront the nation's dependence on imported petroleum. Since the widespread introduction of lead-free gasoline throughout Brazil in 1975, the level of lead in the air in urban zones has diminished by approximately 72 percent. In Mexico, a less extensive program to reduce atmospheric lead was introduced in the 1980s. The Metropolitan Zone of Mexico City, which has monitored air pollutants since 1988, reported significant decreases in atmospheric lead levels, from an annual average of 1.95 µg/m3 in 1988 to 0.28 µg/m3 in 1994. Paralleling this decrease has been an observed lowering of blood lead levels in the residential population in the Metropolitan Zone of Mexico City. Lead exposures related to use of leaded gasoline are highest in urban environments. Residents of intense vehicular traffic areas generally have blood lead levels much higher than populations exposed to less vehicular traffic. The populations of Latin American and the Caribbean are primarily urban—75 percent of all people in the region live in urban zones, and this percentage is expected to increase in the coming years. This fact, coupled with the observation that 30 percent of the population of the region is less than 15 years of age (corresponding to more than 110 million people), signifies that a great proportion of children in the region are, and will continue to be, subject to high levels of lead exposure attributed to vehicular emissions. Continued attention should, therefore, be given to reducing the lead content of gasoline, because this will markedly reduce the lead exposure of a significant proportion of the population in Latin America and the Caribbean. Besides lead from vehicular emissions, other sources of lead exposure in Latin America require consideration. Based on the data from our survey, the local authorities in 87 percent of respondent countries recognized that lead emitted into the air also derives from fixed industrial sources, including smelting, petrochemical processing, and mining. The reutilization and recycling of batteries was recognized as an important source of occupational lead exposure. Of total respondents, 75 percent consider paint to represent an important source of lead exposure in the region, 55.3 percent believed that lead contamination of food represents an additional important source of lead exposure, and 25 percent referred to the contamination of water as a potential source of lead exposure.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

PREVALENCE OF EXPOSURE AND DATA QUALITY OF LEAD CONTAMINATION IN LATIN AMERICA AND THE CARIBBEAN

81

Data on the content of lead in different items in the environment were reported to have been analyzed by some of the countries responding. Samples of air; sediment and dust; food, particularly fish, shellfish, and vegetables; and water were the items most frequently analyzed. Lead levels in some samples surpassed the norms of the World Health Organization. Unfortunately, sufficient data were not available to determine the importance of these sources of exposure to human health in the region. It is also important to remember that few certified laboratories exist in the area with control of internal and external qualities for measuring lead. This limits the interpretation of the research results that are available. Measurements of lead in the general population of children and adults were reported for several of the countries responding. In Table 3-3, one can observe that the levels of lead in the blood are higher in populations that live near fixed sources of lead emissions. Average blood lead levels in children varied from 3.4 µg/dl to 39.0 µg/dl, and the proportion of children having lead in their blood above 10 µg/dl varied from zero to 100 percent. Also, it is important to note that potential exposure of different populations through wastes from battery recycling is very high. In urban populations, lead levels observed in infants ranged from 3.0 µg/dl in Tobago to 28.8 µg/dl in Ecuador. The proportion of young children with lead levels above 10 µg/dl varied between zero and 60 percent. In adult populations, the levels observed are similar, although generally a little higher. In the Metropolitan Zone in Mexico City, blood lead levels have decreased since 1991. Approximately 30 to 50 percent of children are considered to have blood lead levels exceeding 10 µg/dl. This decrease is probably related to the drop in the lead content of leaded gasoline and the introduction of unleaded gasoline in Mexico. In adults, this proportion was slightly greater. One of the factors that could explain this difference is the use of lead-glazed ceramicware, which is still widely used by the adult population. In occupational populations, the levels of lead in the blood were observed to be uniformly high, and these varied by an average of 21.4 to 48.8 µg/dl, with a range of 4.1 to 104 µg/dl. The data collected, however, were insufficient to determine the magnitude of the lead poisoning in these populations. Finally, it is important to determine the government's perceptions regarding the problem of lead, and to know if a given country is taking action to prevent or control lead poisoning. Of the countries responding to this survey, 75 percent indicated that their governments identify lead as a

Copyright © 1996. National Academies Press. All rights reserved.

Urban Fixed source Urban industrial Fixedsource

Adults

Adults

Children

Children

Brazil

Battery recycling

Children

Children

Tobago

Source: Compiled by Isabelle Romieu.

a Estimated

Urban

Mothers

Trinidad

Urban

Fixed source

Children

Rural

Adults

Nicaragua

Rural

Children

Urban

Urban

Adults

Children

Urban

Adults

Uruguay

Urban

Urban

Adults

Children

Urban

Children

Mexico

Urban

Children

Ecuador

Urban

Nursing infants

Chile

Fixed source

Children

Argentina

Location

Population

Country

TABLE 3-3

20

94

94

50

48

92

46

3,309

200

200

83

27

64

200

6

199

71

156

424

n

3–19months

Infants

—

1–6

2–14

15–62

6–8

15–45

15–55

10 µg/dl (percent)

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

PREVALENCE OF EXPOSURE AND DATA QUALITY OF LEAD CONTAMINATION IN LATIN AMERICA AND THE CARIBBEAN 82

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

PREVALENCE OF EXPOSURE AND DATA QUALITY OF LEAD CONTAMINATION IN LATIN AMERICA AND THE CARIBBEAN

83

public health problem. In 50 percent of these countries, legislation exists to regulate the content of lead in different sectors. Only 19 percent of the countries with existing legislation, however, reported that it was routinely enforced. Enforcement, when it does occur, tends to be sporadic and inconsistently applied. CONCLUSIONS This survey demonstrated that there is a lack of data available to evaluate the extent of the problem of lead exposure in the Americas and the Caribbean. Perhaps the data exist, but are not routinely published. It is more likely, however, that the data do not exist. If so, it is imperative that they be collected. The partial results of this survey suggest that lead poisoning is a very important health problem in the region. The principal sources of exposure are related to vehicular emissions, coming from automobiles that use leaded gasoline; industrial use, in particular in paints and batteries; and food. The majority of governments in the region know that lead is a serious health problem, but the actions they have taken to confront the problem have been limited thus far. Based on our survey, 13 countries (36 percent) have realized or initiated changes to introduce nonleaded gasolines, but the use of lead-free gasolines remains limited in the region.

Drs. Romieu and Lacasana wish to thank the following individuals for their valuable contributions: Henri Jouval, Isaias Daniel Gutiérrez, Arend Van de Kork, Philippe Lamy, Manuel Nasif Issa, Armando López Scavino, Celia Castelló, Mauricio Habaca Marileo, Raúl Penna Melo, Franciso José Mardones, Antonio Romero Hernández, Carlos Hilburg, Carlos Alfonso Osorio, Javier Hernán Paiga Coca, Germán Giraldo Salinas, Ramón José Zapata Giraldo, Luis Edilberto Blandon Palomino, Merlin Fernández, Luis A. Leal, Gustavo Mora, Ricardo Núñez, Yamara F. Hernández F., Mauricio Pardón, Gonzalo A. Ordoñez, César Hermida, Carlos A. Linger, Carlos Morales, Fernando Meneses González, Jorge Jenkins, Juan Antonio Casas, Rocio Espinoza Laín, Habib Latiri, Guy Felix, Paul Ellis, Juan Carlos Veronelli, Roberto Solvetella, Jorge W. Bruschem, and Jorge Baso.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

NATURE AND EXTENT OF LEAD EXPOSURES AND TOXICITY IN THE AMERICAS

84

NATURE AND EXTENT OF LEAD EXPOSURES AND TOXICITY IN THE AMERICAS ELLEN K. SILBERGELD*

Lead exposures, both chronic and acute, contribute to the incidence of lead poisoning in many populations in the Americas. While local conditions and source terms are extremely important for understanding the nature of specific risks within communities, there are sufficient similarities among exposures that valuable information can be generalized for purposes of preventive health policy. For purposes of developing hemisphere-specific strategies for prevention, both the local and international aspects of lead exposure are important. Lead is an international problem because of transnational movement of lead released into the air from stationary and mobile sources; because of trade in products containing lead, such as food and painted objects; and because of the movement of lead-containing discards (Silbergeld, 1995). Lead sources may be considered in terms of mass balance; because of the elemental nature of lead, anthropogenic activity that shifts lead from crustal deposits to the human environment increases the likelihood of human exposure. In addition, many lead sources contribute to multiple pathways, complicating exposure assessment. Mexico, Canada, Peru, and the United States are major world lead producers and exporters. Since early European settlement, lead mining and production have been economically important in the hemisphere. Over the past 20 years, lead production and consumption have continued to grow; the largest and fastest growing use of lead is in storage batteries. Lead exemplifies the paraoccupational nature of chemical exposure problems: mining, smelting, and production expose both workers and nearby communities to lead releases; moreover, workers may bring lead dusts home. “Fouling the nest” occurs when lead industries are located near or even conducted in homes, or when parents or children work in lead-using industries and bring the contaminant home with them.

* University of Maryland Medical School, Baltimore, Maryland

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

NATURE AND EXTENT OF LEAD EXPOSURES AND TOXICITY IN THE AMERICAS

85

The complexity of lead source/pathway relationships is demonstrated by analysis of lead in air. As shown in Figure 3-5, lead released from cars first enters the air, where it may be an immediate source of lead exposure by inhalation. Most lead from this source is deposited close to roadways, where it contaminates dusts and soils. This contamination may affect the food supply, particularly foods grown exposed to air; drinking water; and dusts and soils in houses, schools, and other environments. Because of its pervasiveness, lead in gasoline rapidly contributes to human exposure. In the period 1976–1992, the use of lead in gasoline accounted for about 30 percent of median blood lead levels in the United States. While reducing lead levels in gasoline immediately reduces ambient air concentrations of lead (and crop deposition, with a lag time associated with the harvest cycle), lead deposits in soils and dusts remain for decades, offering significant potential sources for exposure. Moreover, actions to reduce lead in gasoline (grams/liter) may not affect overall lead use or air lead concentrations if total gasoline consumption continues to grow, and leaded fuels retain a substantial market share.

Figure 3-5. Sources and pathways of lead from environment to humans. Source: Adapted from EPA, 1986.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

NATURE AND EXTENT OF LEAD EXPOSURES AND TOXICITY IN THE AMERICAS

86

The problem of lead in gasoline and its residuals is similar to the problem of lead in paint. Despite the International Labor Organization convention in the early 1920s against white lead, to which several countries in the Americas are signatory, and despite bans on use of lead-based paint in residences in the United States, millions of tons of lead in paint remain on building surfaces. For example, in the United States this reservoir of past lead use constitutes one of the most intense sources of lead exposure, particularly to young children. Exposure to lead paint and to other sources are often most intense in populations at economic and other disadvantage. In the United States, current (1988-1992) rates of increased lead exposure (blood lead concentrations >10 µg/dl) are five times greater in African American children, and twice as high in poor children, than in affluent white children. The complexity of lead sources can be studied using careful analysis of pathways, and also by stable isotopic techniques. These methods (NRC, 1993) exploit the geochemical differences in lead deposits on Earth. If different sources utilize lead from geochemically distinct sources (such as, for instance, the United States and Australia), then the relative contribution of each source in environmental media and in blood can be defined, using sensitive ultraclean mass spectrometry. Stable isotopic analyses have also demonstrated the importance of bone lead stores as sources of internal exposure during major physiological stages in humans. During pregnancy, lactation, and aging, bone lead may be mobilized back to the circulation and present an opportunity for (re)exposure of the host, or for additive exposure to the fetus during pregnancy. Concerns over the prevalence of lead exposure have focused on the young child, although lead is also recognized as a major health problem for adults, particularly in industry. Children are at risk for three reasons: their exploratory behaviors and hand-to-mouth activity places them at risk of lead exposure, if it is present in their environments; children absorb lead from the gut with 5–10 times the efficiency of adults; and certain cellular targets for lead toxicity may be more sensitive in the young child than the adult. Several major epidemiologic studies, some of them prospective in design, have associated relatively small increases in body lead burden with persistent problems in learning and school attainment. In addition, prenatal lead exposures are associated with decreased growth in stature and delays in neurobehavioral development. As shown in Figure 3-6, increases in body lead burden (as measured by dentine lead levels in teeth) were associated with decreased attainment on

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

NATURE AND EXTENT OF LEAD EXPOSURES AND TOXICITY IN THE AMERICAS

87

Figure 3-6. Deficits in psychologic and classroom performance of children with elevated dentine lead levels. Source: Reprinted, with permission, from Needleman, H.L., et al. “Deficits in psychologic and classroom performance of children with elevated dentine lead levels,” The New England Journal & Medicine 300 (13):689-695. ©1979 by the Massachusetts Medical Society. Note: The distribution of Negative Ratings by Teachers on 11 Classroom Behaviors is provided in relation to dentine lead concentration. The group boundaries were chosen to obtain symmetrical cell sizes for the median (Groups 1 and 6=6.8 percent; Groups 2 and 5= 17.6 percent; and Groups 3 and 4= 25.6 percent).

neurocognitive tests and unfavorable assessments of learning and behavior by teachers. No “threshold” for these effects was discernible. Basic research on lead toxicity supports these associations, as well as the conclusion that lead neurotoxicity may be largely irreversible.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

NATURE AND EXTENT OF LEAD EXPOSURES AND TOXICITY IN THE AMERICAS

88

As shown in Figure 3-7, lead can penetrate inside neurons in the central nervous system (CNS) and, once inside, it cannot be removed even by strong chelators (such as dithiothreitol) in vitro. In the CNS, lead can disrupt neuronal communication and memory storage through actions at several molecular targets: ion regulation by Na-K ATPase and conductance channels; neurotransmitter receptor and transporter binding; intracellular calcium storage and release; and intraneuronal second messenger proteins such as adenyl cyclase and protein kinase C. These effects occur at lead concentrations as low as 1 pM. During development, some of these actions may have persistent if not permanent sequelae, because neurotransmitters play a trophic role in “hardwiring” the CNS during early perinatal stages. By impeding cell:cell communication at these stages, lead exposure may permanently prevent appropriate development of regional and interregional connectivity. The possibility that lead exposure

Figure 3-7. Subcellular localization of lead I synaptosomes. Source: Silbergeld, 1992.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

NATURE AND EXTENT OF LEAD EXPOSURES AND TOXICITY IN THE AMERICAS

89

during aging may also have neurotoxic effects is only now being studied, specifically in the context of new information on the alterations in lead storage and toxicokinetics that occur during aging and after the menopause in women. These data demonstrate that in order to fully eradicate lead poisoning, it is necessary to control both ongoing sources of lead into the environment and to evaluate the risks of existing reservoirs from past uses. In addition, understanding the range of lead toxicity is required to develop focused public health programs of surveillance and intervention. Experience demonstrates that the most effective means of lead exposure reduction are bans or substitutions on uses of lead in products such as gasoline, food cans, and paints. The continued prevalence of lead poisoning attests to the need to continue to reduce human exposure.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

NATURE AND EXTENT OF LEAD EXPOSURES AND TOXICITY IN THE AMERICAS 90

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

91

SESSION D

Case Studies of Interventions

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

92

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

INTRODUCTION: CASE STUDIES OF INTERVENTIONS

93

INTRODUCTION: CASE STUDIES OF INTERVENTIONS DAVID RALL*

The task of reducing lead exposures and preventing lead poisoning across the Americas seems a daunting task. This session highlights four case studies of interventions in different sectors. The first describes a successful voluntary industry initiative in Mexico to remove lead solder from the canning process. The second presents an example of government regulation—in this instance, the U.S. Clean Air Act—that dramatically reduced population lead levels in the United States. The third case study explores the role of international organized labor—in this case the U.S. Carpenter's Union—in educating and training workers about lead poisoning and describes the union's efforts to work with government agencies to ensure stricter protective policies for workers and their families. The final case study describes the role of community activism and education in empowering local communities in Mexico to design and implement focused public health programs to reduce lead exposure in their populations. What these four case studies illustrate is that successful control and prevention strategies require the involvement of people and organizations at all levels of society, from the federal sector down to the grassroots or community. Lead poisoning is a problem that directly affects people at all levels of society. Its solutions must, therefore, also be shared.

* Retired, National Institute of Environmental Health Sciences, USA.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

VOLUNTARY INDUSTRY INITIATIVE: REMOVAL OF LEAD SOLDER FROM CANS

94

VOLUNTARY INDUSTRY INITIATIVE: REMOVAL OF LEAD SOLDER FROM CANS ALFONSO DE LEÓN*

In 1992, the metallic containers industry in Mexico stopped producing tin cans with lead soldering as food containers, substituting instead a process that closes tin cans with electrical solder. Mexican public health authorities are now interested in determining whether a quantifiable reduction in population blood lead levels, especially in children, has occurred as a result of this voluntary industry change. The National Chamber for Metallic Containers of Mexico represents more than 85 percent of steel tin can and 100 percent of aluminum tin can production, making it the leading manufacturer of metallic containers in Mexico. The process leading to the total elimination of lead soldering in food cans was begun as a voluntary initiative by industry, although the increased pace of change in the latter phases of conversion was dictated by external events. This process is described briefly below. Metallic containers have been used to hold and conserve food for more than 180 years. In the beginning, tin was used in soldering, but it resulted in little flexibility and a fragile seam. Lead rapidly replaced tin in solder because it is a ductile material that easily adheres to the tin plate and can be mixed with the tin to produce a more flexible and less fragile soldering. At one point the solder commonly used contained 90 percent lead and 10 percent tin. Such soldering was universally adopted and, with it, many billions of cans were produced globally, without an understanding that lead in external soldering posed a public health hazard. When medical and public health authorities began to acknowledge concerns about the effects of lead exposure on human health, attempts were made to identify the different sources of the metal. Leaded gasoline, paints, and ceramicware glazes and food cans containing leaded solder were rapidly identified as important sources.

* National Chamber for Metallic Containers, Mexico City, Mexico.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

VOLUNTARY INDUSTRY INITIATIVE: REMOVAL OF LEAD SOLDER FROM CANS

95

Manufacturers of metallic containers had already began, by the late 1970s, to substitute lead soldering with electric soldering. This change was instituted for reasons apart from public health concerns about lead, which remained largely unknown at the time. The main motives for converting to electrical soldering were to have a cleaner production process, greater productivity, and a larger surface area on the cans for the purposes of advertising (leaded seams are broader than electrically soldered seams). Mexico adopted the electrical soldering technique, despite the many lead soldering production lines that still had many years of usable life and the $1.2-2.0 million investment that was required to refit production lines. This change was an unusual one for Mexico, which does not usually afford itself the luxury of getting rid of production equipment that is still considered useful. At the beginning of 1991, a strong popular movement against lead in the environment was organized in Mexico City. The metallic container industries became involved in this movement, along with other lead industries. As an outcome, ecologists, united with health authorities, insisted that the electrical soldering substitution process that had been under way for over 10 years be abruptly accelerated. We cannot deny that moments in the ensuing deliberations were amusing. The industry's basic argument in 1991 against an abrupt acceleration in the substitution process was based on the following: (1) in 1979 the industry voluntarily initiated a gradual substitution of production lines that utilized lead solder; (2) the cost for substituting each line was too high to warrant wholesale, rapid substitution; (3) until research proved that inward migration of lead from the external soldering of tin cans was contributing to the amount of lead in canned foods, accelerated action was premature; and (4) the recommended threshold for lead in foods was still subject to debate. To support industry's argument, we noted U.S. FDA reports that indicated similar voluntary changes occurring at the same pace in the U.S. metallic container industry. According to these reports, in the early 1980s, 90 percent of tin cans produced in the United States had leaded solder; by the 1990s, the proportion had dropped to approximately 4 percent and was expected to decrease even more in the coming years. Clearly, industry in two major markets was voluntarily making changes, and the demand that the Mexican sector suddenly accelerate its rate of conversion—at considerable additional cost—was unfair. The FDA, to my knowledge, has not yet been able to establish legislation totally prohibiting the use of lead soldering in tin cans for food. In 1994, for

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

VOLUNTARY INDUSTRY INITIATIVE: REMOVAL OF LEAD SOLDER FROM CANS

96

example, 139,000 million tin cans were produced in the United States; of these, 20,000 million were three-piece tin cans used for food. Assuming that only 2 percent of these had lead soldering means that 400 million tin cans would have still contained lead soldering. It is our industry's belief that, in the United States, voluntary action by industry will eliminate lead soldering in the near future without the need for legislation. Returning to the story in Mexico, none of the arguments listed above swayed the necessary Mexican decisionmakers. Health authorities, pressured by ecologists, continued to demand immediate conversion to electrical soldering. This activity culminated in the 5 July 1991 signing of the “Actions for the Integral Solution of the Problems Related to Lead Content in Products that Could Constitute a Risk for Health and Ecosystems” in Mexico City. The National Chamber for Metallic Containers agreed in this document to accelerate the transformation of all of its production lines in order to eliminate lead from the soldering process. We were given a very short time to complete the necessary changes. This posed special problems—for example, the machinery for producing electrical soldering was manufactured in Europe and required 10 to 12 months for delivery. Our organization was also required to close 15 new production lines. Recognizing the difficulties of implementing wholescale change in a short time frame, the Mexican government generously granted our industry 18 months to fulfill our task. At that time, as an active member of the “Normalization of the Metallic Food and Drink Containers Subcommittee,” I began work with colleagues on the elaboration of a preliminary program to regulate the types of solder that would be permitted on tin cans for food. On 2 June 1993, a text of the program was made available and accepted by both the private and public sectors. The health secretary in the Office of the General Management of Environmental Health visited our plants to verify that lead soldering had effectively been eliminated from the soldering process. Finally, on 11 November 1993, the report of the subcommittee was published in the Diario Oficial (Mexico's largest newspaper). According to the law, 90 days were given to interested parties to express comments and concerns about the proposed project. On 8 February 1994, the secretary of health held a meeting to analyze the commentaries given. Revisions were made, and the final text revised. On 14 November 1994, the Norma Oficial Mexicana (Official Mexican Norm) NOM-002-SSAT-1993 “Metallic Containers for Food and Beverages: Seal Specifications and Sanitary Requirements,” was published in the Diario Oficial.The norm prohibits the use of

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

VOLUNTARY INDUSTRY INITIATIVE: REMOVAL OF LEAD SOLDER FROM CANS

97

lead soldering in metallic containers for food. The norm is also applicable to imported products, serving as a way to prohibit lead-soldered cans from entering the country. Helped by a loan of $35 million, our industry had fulfilled its commitment to change to lead-free soldering in the 18 months accorded us. One aspect of Mexico's experience that was not given the attention it deserved was the unfilled need for assistance to workers who had been poisoned through occupational exposure to the lead soldering process. On many of our old production lines, the containers of melted solder sat open, generating lead fumes. Systems of absorption and filtration existed for these emissions, but were rarely adequate. In addition, masks usually given to workers were frequently not used because the workers complained of hindered breathing. As a result, cases of lead poisoning were common, and many of these workers still require medical attention. Our organization also believes that food containing lead before processing and canning should be given careful attention. Tuna, for example, because of its metabolism, has a tendency to absorb heavy metals such as lead, cadmium, mercury, and arsenic. The National Institute of the Consumer (INCO) of Mexico on one occasion reported large amounts of canned tuna containing lead above the threshold limit established at that time. The cans in which the tuna was stored were of the two-piece variety that did not contain solder of any kind.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

A CASE STUDY IN GOVERNMENT REGULATION: U.S. GASOLINE LEAD REDUCTION

98

A CASE STUDY IN GOVERNMENT REGULATION: U.S. GASOLINE LEAD REDUCTION ROBERT A. SCALA*

This paper will trace a successful story of government intervention to reduce the risk of airborne lead intake and possible lead poisoning. The story is told from the perspective of the U.S. Environmental Protection Agency (EPA), the main government agency involved. Lead had been used as an additive in gasoline from the 1920s to boost octane and to provide lubrication for certain engine parts. Tetraethyl lead and tetramethyl lead, both high in octane value, lubricate intake and exhaust valves and help to reduce engine knock (EIA, 1992). Over time the use of additives became increasingly widespread, and the amount in fuel increased as octane demand increased. Although the limit for lead in gasoline was approximately 4 grams a gallon, a usage level of 2.5 g/gal was more typical. Because of increasing health and environmental concerns over atmospheric lead, lead reduction began with the 1970 Clean Air Act, which authorized restrictions on the use of lead in gasoline. In 1970 there were almost 90 million passenger cars registered in the United States, and motor gasoline consumption was 5.78 million barrels daily (approximately 915 million liters daily). Under the Clean Air Act, the U.S. EPA was authorized to regulate fuels and fuel additives. Unleaded fuels also appeared in the early 1970s. Auto manufacturers were required to design and build vehicles that could operate on unleaded fuels or low-lead fuels, and a schedule was set for the reduction of lead levels in leaded fuels. Before the Clean Air Act, the EPA had strong concerns about the potentially harmful effects of lead, but was unable to persuade the scientific community or industry that airborne lead represented a health hazard outside the workplace. Under the Clean Air Act, the EPA was given the authority to control airborne lead attributable to motor vehicle emissions for reasons beyond potential health hazards. A 1980 National Research Council publication outlined a model for regulatory decisionmaking re

* Retired, Exxon Biomedical Sciences, Inc., Rehoboth Beach, Delaware.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

A CASE STUDY IN GOVERNMENT REGULATION: U.S. GASOLINE LEAD REDUCTION

99

garding potential health hazards of environmental agents (NRC, 1980). There were nine steps: 1. 2. 3. 4. 5. 6. 7. 8. 9.

Identify sources of lead and pathways of environmental transfer; Identify specific human populations with exposure to lead; Estimate the level of exposure to lead by each environmental pathway for each specific population; Establish the association between exposure to lead and the level of lead in the body for each specific population; Establish the association between the level of lead in the body and biological change caused by lead for each specific population; Estimate the upper limit of nondetrimental biological change for each specific population and the level of lead in the body associated with that degree of biological change; Identify and describe alternative control strategies; Apply risk-benefit, cost-benefit, and other considerations, compare alternatives for control, and decide what is an acceptable level of lead in the environment for each specific population; and Evaluate the process and the decision. SOURCES AND PATHWAYS

Of greatest interest with respect to motor gasoline is its contribution to airborne lead. The amount of lead in the air appears to be related in large measure to the amount of lead in fuel. Leaded fuels generated 24,000 µg/m3 of lead at the tail pipe in the era before lead phasedown (NRC, 1993). Typical lead levels in urban environments in the 1970s were in the range of 0.5 to 10 µg/m3, and perhaps 90 percent of this is attributable to lead from gasoline. Most lead is emitted as halides and oxides, but virtually all of it is eventually converted to the sulfate. Most of the lead is deposited near the vehicular source. Particles with diameters in the range of 10 µm are deposited over a broad distance, and there is long-range transport of particles with a diameter of less than 0.1 µm for over a month (NRC, 1993). Lead is widely distributed in the body, with a preferential uptake by bone. EXPOSED POPULATION From the outset, EPA held that leaded gasoline was a source of air and dust lead that could be reduced readily and significantly in comparison with other sources. It also held that young children in the age range of 1 to 5

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

A CASE STUDY IN GOVERNMENT REGULATION: U.S. GASOLINE LEAD REDUCTION

100

years should be regarded as a group sensitive to lead exposure (EPA, 1978). The third link in the EPA chain of logic is that contaminated dust and dirt from motor vehicle exhausts are the most important exposure routes for children (EPA, 1973). The health status of children was the principal driving force for the regulation of the lead content of fuels. As late as 1984, about 6 million children and 400,000 fetuses in the United States were exposed to lead at concentrations that placed them at risk of adverse health effects, defined as blood lead levels of at least 10 µg/dl (NRC, 1993). EXPOSURE-BODY BURDEN ASSOCIATION The EPA put great emphasis on the work of Azar et al. (1975), which showed a ratio of lead in the air to lead in the blood of 1:1.8 at airborne levels of 1.5 µg lead/m3, where lead in blood was expressed in the usual terms of µg/dl (micrograms lead per deciliter of blood). The work was in adults, not children. the EPA holds that children have a greater net absorption and retention of lead than adults. The agency assumes that the air-lead to blood-lead relationship for this sensitive population exposed to lead in ambient air equals or exceeds the relationship for adults. The literature also suggests (ACGIH, 1991) that this relationship is nonlinear with concentration in air. Yankel et al. (1977), using children living near a smelter, found an average ratio of 1:1.9. Some of the nonlinearity in the relationship is explained by particle size changes with concentration, 24-hour vs. 8-hour exposures, and certain kinds of avoidance behavior by workers. BODY BURDEN-EFFECT ASSOCIATION Preceding presentations have discussed the issues centering on clinical and subclinical effects of various body burdens of lead, expressed either in blood lead levels or tissue concentrations. the EPA emphasized minimizing lead burden. The agency position was that air lead contributed to general population lead exposure and that airborne lead levels below 2 µg/m3 affect blood lead levels. With the promulgation of a National Ambient Air Quality Standard for Lead in 1978 (EPA, 1978), the EPA stated that for the sensitive population previously defined (children ages 1–5 years), a blood lead level above 30 µg/dl was associated with an impairment in heme synthesis in cells, as indicated by an elevation in erythrocyte protoporphyrin. This finding was judged by the EPA to be adverse to the health of chronically exposed children. the EPA also declared that there were a number of other adverse health effects associated with blood lead

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

A CASE STUDY IN GOVERNMENT REGULATION: U.S. GASOLINE LEAD REDUCTION

101

levels above 30 µg/dl in children, as well as in the general population. Three systems appear to be most sensitive to the effects of lead: the hematopoietic system, the nervous system, and the renal system. Inhibition of enzymes systems has a threshold as low as 10 µg/dl; at the other end of the scale, permanent, serious neurological damage or death have thresholds approaching or exceeding 80 to 100 µg/dl in children. CONTROL STRATEGIES AND OPTIONS The EPA acknowledged that the lead exposure problem arose from a combination of sources, including food, water, air, leaded paint, and dust. The contribution of each source varies depending on the environment, bioavailability, and individual exposure and uptake. Reducing lead from all sources would improve health; the EPA, however, viewed lead in gasoline as a source of air and dust lead that could be readily and significantly reduced. The first steps taken to reduce lead in gasoline in the United States resulted from the introduction of the platinum-based catalytic converter. This device, which reduced emissions of polycyclic aromatic hydrocarbons and other pollutants from gasoline, was damaged by lead. Starting in 1973, it was necessary for EPA to ensure a supply of lead-free fuels for new cars equipped with catalytic converters. In 1978, EPA moved to evaluate the public health benefits of removing lead from gasoline in order to reduce lead in the ambient environment. The initial regulations set quarterly limits on allowable amounts of lead used by refiners and permitted averaging this amount across all grades of gasoline produced. It was assumed that the natural replacement of older vehicles with cars requiring unleaded fuels would result in the programmed reduction of lead in gasoline, without further intervention by government. By 1982, however, two trends were recognized that prevented this natural reduction: first, a substantial number of motorists continued to use leaded gasoline because of its lower pump price (misfueling); and second, since the allowable content of gasoline was defined as the average of all fuels produced, the per gallon content of leaded gasoline could actually increase as the fraction of leaded/unleaded decreased. Because of these two phenomena, the EPA took further regulatory action to ensure the phasedown of lead in gasoline in 1983–1985. Simply by changing the basis of calculating allowable levels of lead in gasoline from the total fuel base to leaded gasoline only, EPA caused a substantial decrease in the amount of lead used in gasoline. In 1990, the U.S. Congress mandated the eventual phaseout of lead in gasoline in the United States.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

A CASE STUDY IN GOVERNMENT REGULATION: U.S. GASOLINE LEAD REDUCTION

102

ENVIRONMENTAL IMPACT There were some environmental consequences of the motor gasoline lead phasedown. One was misfueling, or using leaded fuel in a vehicle designed to use unleaded fuel. Misfueling was found in about 6 percent of vehicles in the inspection and maintenance programs. Of interest is how much lead use was reduced by the phasedown of leaded fuels. With the introduction of the catalytic converter in 1973, the next 10 years showed an increase in unleaded gasoline use. By 1983, unleaded fuel was just over 50 percent of the total gasoline market in the United States, and by 1995 it represented almost the entire market. the EPA estimated a 34 percent reduction in lead use over the interval 1983–1990, with a savings of almost 130,000 tons of lead (EPA, 1982c). Natural Resources Defense Council figures estimate more comprehensible figures. Lead used in motor gasoline in the United States totaled 243 thousand metric tons in 1971; 309 thousand metric tons in 1976; and 138 thousand metric tons in 1981. When the phasedown really took effect, lead use was reduced to 7.1 thousand metric tons in 1986 and 4.4 thousand in 1992 (NRDC, n.d.). BARRIERS TO CHANGE Companies that sold lead additives for gasoline were faced with the prospect of seeing their business virtually vanish over a period of just a few years. They were in the position of buggy whip makers at the beginning of the automotive era. The prudent companies diversified. There was also some reasonable resistance on the part of auto manufacturers. Lead in gasoline not only provided octane value but was also a lubricant for engine parts. The presence of lead prevented valve seats from being “beaten in” because the relatively soft lead deposits provided a form of cushion. Work on metallurgy had to be done as part of the lead phaseout. In the end, unleaded and lowlead gasolines were widely available on schedule. ECONOMIC ANALYSIS The EPA examined the costs of lead phasedown in terms of reduced lead use (EPA, 1984). The agency estimated that the marginal cost of removing lead from gasoline was about U.S. 1¢ for each gram of lead. EPA also found that lead removal presented a positive cost-benefit. The benefit fell into three

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

A CASE STUDY IN GOVERNMENT REGULATION: U.S. GASOLINE LEAD REDUCTION

103

categories: savings on vehicle maintenance, reduced misfueling, and reduced health care costs. For the period 1986–1988, the projected 0.1 gram per gallon for leaded gasoline would produce annual benefits over costs of greater than $1 billion ($1,000 million). MEASURES OF SUCCESS The findings of the National Health and Nutrition Examination Surveys II (NHANES II), which covered the period of 1976–1980 (NRC, 1993), used a stratified multistage probability cluster sample of U.S. households. Blood lead levels were measured for persons aged 6 months to 74 years, and almost 10,000 samples were used. As Figure 3-8 depicts, there was a striking

Figure 3-8. Lead used in gasoline production and average NHANES II blood lead (February 1976-February 1980). Source: Reprinted, with permission, from J.L Annest, “Trends in the bood lead levels of the U.S. population: The Second National Health and Nutrition Examination Survey (NHANES II) 1976-1980,” in Lead Versus Health, M. Rutter and R.R. Jones, eds., New York: John Wiley & Sons. ©1983, John Wiley & Sons, Ltd.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

A CASE STUDY IN GOVERNMENT REGULATION: U.S. GASOLINE LEAD REDUCTION

104

association between declining lead levels in gasoline in the period of 1976-1980 and the subsequent decline in blood lead levels in the U.S. population. Although the choice of scale for each of the vertical axes in Figure 3-8 permitted the dramatic overlay of the declines in amount of lead in gasoline and blood lead levels, one is hardpressed to deny that the association is not a correlation. For NHANES III (Pirkle et al., 1994), the survey covered the period 1988-1991, with over 12,000 blood samples from a population whose ages ranged upward from one year. The mean blood lead level of persons aged 1-74 years decreased 78 percent, from 12.8 to 2.8 µg/dl, a drop of 10 µg/dl. Comparable percentage decreases were seen for non-Hispanic white and non-Hispanic black children aged 1 to 5 years. There was a decrease in the prevalence of blood lead levels equal to or greater than 10 µg/dl, from 85 percent to 5.5 percent for non-Hispanic white children and from 97.7 percent to 20.6 percent for nonHispanic black children. The authors attributed the majority of this decrease in blood lead levels to the virtual removal of lead from gasoline and the reduction of lead in soldered cans (Pirkle et al., 1994). SUMMARY Government intervention in the form of control regulations can be successful in reducing the body burden of lead in the population as measured by blood lead levels. This reduction in burden surely represents a comparable reduction in the risk of lead-related diseases and dysfunctions.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

ACTIVISM: THE ROLE OF ORGANIZED LABOR IN PROMOTING A HEALTHY WORKPLACE

105

ACTIVISM: THE ROLE OF ORGANIZED LABOR IN PROMOTING A HEALTHY WORKPLACE JOHN D. REPKO*

The United Brotherhood of Carpenters, with about 550,000 members in North America, has members who work in all aspects of the trade, including general construction, renovation, and repair, as well as working on bridges and other steel structures. Our members work in buildings and on steel structures known to contain leadbased paint. Piledrivers are frequently exposed to lead-based paint when applying acetylene torches to bridges undergoing renovation. HEALTH EFFECTS Lead intoxication is a continuum, in which the adverse effects are expressed at the cellular, organ, or whole organism level, depending on the dose (Silbergeld et al., 1991). There is no magic level; the toxic effects of lead are evident when increased absorption begins. In addition to working in an occupation that exposes a worker to lead, the worker may come to the job with exposures to lead from the home or living environment. Whatever standards are ultimately established for workers, they must provide for this margin of prior exposure. “Take-home” lead is also a concern. Recently the National Institute for Occupational Safety and Health (NIOSH) (Sussell, in press) reported 62 incidents worldwide of paraoccupational, or “take-home” lead exposure. Industries with reported paraoccupational lead exposures included lead smelting, battery manufacturing and recycling, radiator repair, electrical components manufacturing, pottery and ceramic production, and stained glass making.

* United Brotherhood of Carpenters, Washington, D.C.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

ACTIVISM: THE ROLE OF ORGANIZED LABOR IN PROMOTING A HEALTHY WORKPLACE

106

INTERVENTION STRATEGIES The Carpenters' general approach to intervention is very much proactive. Generally, our approaches fall into four categories: (1) education and training, (2) collaboration with scientists involved in occupational health research, (3) support for occupational and environmental health standards and regulations, and (4) what we call, “dealing an honest hand.” Education and Training Health and safety education for workers about the occupational dangers of lead exposure is an important part of both apprenticeship education and the ongoing training of the journeyman. The U.S. Society for Occupational and Environmental Health, for example, developed a document that was used extensively by the EPA in the development of regulations governing required curriculums for lead-based paint worker and supervisor training (SOEH, 1993). This document and the training programs it has engendered have been effective among our membership in preventing work-related diseases and injuries, keeping workers up-to-date, and helping workers develop an attitude and willingness to practice prevention. Collaborative Research The Carpenters have collaborated on many research activities designed to identify health problems arising from workplace exposures to lead. In 1991, Dr. Irwin Selikoff, who headed Mount Sinai Environmental Sciences Laboratory, in collaboration with NIOSH and Harvard Medical School, conducted the first membershipwide screening of Carpenter workers. A subgroup underwent an even more detailed study, including questionnaires on lead exposure history, blood lead testing, and in vivo measurement of bone lead levels. The study found that age was the dominant predictor of both tibia and patella bone lead. Demolition, carpet laying, and alcohol ingestion were also significant predictors of bone lead (Watanabe et al., 1994). The authors concluded that the data reflect a subclinical effect of bone stores of lead on hematopoiesis and that this effect is the first epidemiologic evidence that bone lead may be an important biologic marker of ongoing chronic toxicity. The researchers also found that the differences in concentrations of bone lead between the tibia and patella are suggestive of ALAD-2-associated pharmacokientic effects. Further, they suggest that subclinical lead-associated kidney dysfunction is found with relatively low

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

ACTIVISM: THE ROLE OF ORGANIZED LABOR IN PROMOTING A HEALTHY WORKPLACE

107

current blood lead concentrations, and that the ALAD-2 genotype may be an additional modifier of this effect (Smith et al., 1995). The Carpenters have also worked with Dr. Selikoff's successors, a network of devoted scientists, by promoting continued study of the membership. These studies demonstrate that information useful to workers' health can be obtained when workers and unions collaborate with their scientific and academic colleagues. By providing additional evidence of lead's toxicity at very low blood and bone levels, such studies can promote changes in occupational standards that better protect the health of workers. Occupational and Environmental Regulation Numerous standards have been set for lead in both the occupational and nonoccupational setting. Some standards set limits on allowable concentrations of lead in the ambient air or workplace air, as well as other environmental compartments, and some standards are based upon biological monitoring. In the workplace, both airborne lead and biomarkers are components of preventing lead poisoning in most national systems. The U.S. occupational lead standard was promulgated in 1978, one of the first de novo standards developed by the Occupational Safety and Health Administration (OSHA), without reliance on earlier guidelines proposed by the American Council of Government and Industrial Hygienists (ACGIH). the OSHA lead standard was noteworthy in that it proposed both a limit on airborne lead in the workplace (50 microgram/m3) and a mandatory program of biological monitoring in most work settings. In addition, the OSHA standard protected worker health and employment rights by establishing a medical removal program: workers whose blood lead levels exceeded the standards were temporarily shifted to jobs without lead exposure with no loss of pay, benefits, or seniority. This approach was intended to change the incentives in the labor management relationship, to encourage employers to reduce lead exposures, and to protect workers from job termination or loss of income. In the United States, occupational standards cover most, but not all, workers exposed to lead. In 1993 the lead standard was finally extended to workers in the construction industry, who are often highly exposed to lead during repair and maintenance of steel structures (which may still be painted with lead-based paints); demolition workers; and workers involved in abating lead hazards in housing. Small workplaces are still imperfectly covered, and some of these, such as battery repair shops, may be sources of intense exposure that not only pose problems for workers, but

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

ACTIVISM: THE ROLE OF ORGANIZED LABOR IN PROMOTING A HEALTHY WORKPLACE

108

can also be sources of contamination to workers' homes and releases to the environment (Matte et al, 1989b; Nunez et al, 1993). In several countries of the Americas, informal “cottage industries,” such as recycling facilities, are almost wholly outside any regulatory surveillance, as demonstrated in a report from Tijuana, Mexico (Leung, 1988). Dealing an Honest Hand Historically, organized labor and the lead industries have not had an easy relationship. A number of incidents illustrate their lack of cooperation. The events surrounding the American Smelting and Refining Company (ASARCO) lead smelter emissions in El Paso, Texas, in the late 1960s (Repko et al., 1978) and the Bunker Hill smelter in Kellog, Idaho, in the 1970s (EDF, 1992) are two such examples. The lead industry also consistently attacks studies that demonstrate a causal relationship between lead exposure and adverse health effects in order to counter this increasing body of evidence. Another industry approach is to claim simply that lead is not a problem and that nothing, therefore, needs to be done about limiting exposures to the metal. As a result, labor has had to consistently challenge the positions taken by the lead industry. NIOSH's legal right of entry, for example, has been used to conduct health hazard evaluations in the workplace. Because of the active involvement and support of labor, however, the lead industries have never won a major victory over the EPA or OSHA, the government organization most responsible for worker health. In response, there is a current effort by industry to shift its worksites into international markets where regulation is less restrictive or does not exist. Moreover, environmental advocacy groups or scientific communities may also be absent or small in a number of these areas. Workers all over the world are increasingly under attack by corporate and financial interests who use the globalization of products such as lead as a lever to restrict worker rights and to lower workplace standards. It is the responsibility of labor to fight against this trend. CONCLUSIONS Workers continue to be poisoned by lead on the job. Members of labor groups or health professionals can help reduce worker exposure in several ways:

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

ACTIVISM: THE ROLE OF ORGANIZED LABOR IN PROMOTING A HEALTHY WORKPLACE

109

• Worker education is the first step to prevention. Workers have the right to know. An informed workforce increases its control over its exposure. Inspectors and government officials responsible for workplace health and safety must also be well-trained and informed about lead hazards. • International and national protective standards for workers should be widely adopted across the Americas, but these should not necessarily copy those of the United States. Labor and workers should have an opportunity to establish stringent standards for lead exposure consistent with new scientific evidence that was not available or not used when the United States first set its standards. • Existing environmental or workplace standards that limit workers' exposure to lead must be enforced. To adequately enforce regulations will require a coordinated effort by an educated workforce, competent inspectors, an effective judicial system, and policymakers who can support the courts and the inspectors. • Productive collaborations among unions, scientists, occupational health professionals, and academics should be fostered. • Union officials should be informed of the importance of occupational health and encouraged to raise the level of workers' health to the same level of concern in contract negotiations that is routinely given to economic issues. • Finally, persist, and don't give up. Whenever new ways of making a dollar, peso, real, other currency involve new hazards, those who work to protect worker health are playing “catch up.” Remember that it is always the workers who pay first and worst.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

COMMUNITY ACTIVISM AND EDUCATION: ACCESS TO NEW KNOWLEDGE AS A BASIS FOR COMMUNITY EMPOWERMENT

110

COMMUNITY ACTIVISM AND EDUCATION: ACCESS TO NEW KNOWLEDGE AS A BASIS FOR COMMUNITY EMPOWERMENT CHRISTINA VON GLASCOE, M.D., PH.D. * If people in the developing world are to have radically improved lives, it is first of all necessary to teach them to be dissatisfied with the present situation and at the same time make them appreciate how they can work towards a better future. Bidwell, 1988

Environmental health issues are of recent concern at the northern border of Mexico, but to date have not been addressed in a concerted fashion by either community interest groups or public health authorities. For example, public health authorities and two major nongovernmental organizations (NGOs) working in primary care and family planning in Tijuana, Mexico, have yet to incorporate environmentally driven concerns such as lead poisoning into their regular health activities. Nevertheless, there are indications that lead poisoning and other environmental health concerns are gaining visibility at the local level in Mexico, as they are elsewhere in the Americas. A major requirement in creating the necessary infraculture for community-based action is the need to increase popular knowledge and public awareness of environmental health hazards and the steps that can and should be taken to reduce these hazards. An example of such work is provided in this paper. Ways to incorporate such knowledge into the cultural horizon of a community under environmental health stress are highlighted. DEFINING THE CULTURAL HEALTH HORIZON Anthropologists interested in health recognize that community members practice a wide range of activities related to public health, with or without the direction of health authorities. In any community there coexist interpretations of an official and a traditional system of dealing with public health threats, and these do not necessarily influence each other. In order to deal

* North Border College, Tijuana, Baja California.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

COMMUNITY ACTIVISM AND EDUCATION: ACCESS TO NEW KNOWLEDGE AS A BASIS FOR COMMUNITY EMPOWERMENT

111

effectively on a grassroots level, it is necessary as a first step to define the “cultural horizon” of the community. Broadly defined, the cultural horizon is the wide range of public health activities practiced by community members, with or without the direction of the health authorities. Thus, the development of effective community strategies to reduce or prevent lead poisoning will depend not only on information on the sources of contamination and number and distribution of cases identified, but also on being able to convey that information in a manner that is reflective of the community's cultural horizon. That horizon can be defined by a number of factors, including: • the level of personal behavior engaged in health promotion (individual, family, and community/public); • the level of interaction and cooperation with local health authorities in matters of personal and public health. THE CULTURAL HEALTH HORIZON AND THE DEVELOPMENT OF THE LOCAL HEALTH SYSTEM Responsibility for health is transferred to individual households through the empowerment of individuals to act in ways consonant with that responsibility. Assumptions underlying this transition are: • People will act responsibly on their own behalf given sufficient information, resources, and interest, and in the context of a particular cultural horizon that sanctions this behavior; • Information can consist of information and resources, but interest must be stimulated from within the community. Information presentation in and of itself does not guarantee the “success” of communitybased programs; • Health professionals need to determine what the focus of prevention activities should be; • The potential threat of a hazardous substance must be made visible to the community so that it may be communicated in ways that can be understood by community members. In transmitting this information, it is imperative to impart knowledge on specific steps that can and should be taken by community members to reduce their exposure, and that of their families, to the hazardous substance in question. Allowances should be made for community-driven modifications in these steps deriving from the culture or other values of the inhabitants.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

COMMUNITY ACTIVISM AND EDUCATION: ACCESS TO NEW KNOWLEDGE AS A BASIS FOR COMMUNITY EMPOWERMENT

112

Underlying these four assumptions is the recognition that in the past, the community has often been the missing link in addressing environmental and occupational health problems at the local level. The community has often been excluded because members were not considered knowledgeable enough to participate in problem solving. While this paternalistic belief continues to be held by many traditional health professionals, particularly in less-developed countries or in inner-city or rural regions of the more developed countries of the Americas, there is a growing movement toward including community members and other “stakeholders” in the development and implementation of prevention and control programs. Growing experience indicates that such individuals can be vital to the development of innovative and sustainable solutions. Thus, community empowerment should remain a cornerstone of prevention and control efforts. ALIGNING HEALTH AUTHORITY INTERESTS WITH THOSE OF A COMMUNITY The best community interventions expand the cultural health horizon of a community by adding culturally relevant alternatives to standard or “textbook” approaches to prevention. In order to do this, the goals and methods of agencies must be aligned with the goals and methods of the community; in other words, they must be made relevant to the community members and vice-versa. How can this be done? The first step is to appraise the “health horizon" of the community—for example, by determining, in the case of lead, the level of personal behavior directed toward reducing industrial and family exposures. The current degree of information exchanged about the sources and nature of lead poisoning in the community and the interaction between the public health authorities and community members on health issues important to the community also need to be assessed. As a general rule, we have observed that where the health authorities have a strong bureaucracy, community leadership is suppressed, and health professionals manage the public's health; conversely, where the public health bureaucracy is weak, alternative forms of representation naturally arise. For example, in underserved areas, health authorities are often helped by local grassroots organizations and other NGOs. As a consequence, some of the most innovative experimentation in community education and empowerment is occurring in the most economically disadvantaged populations or in rural areas. This experimentation should be carefully studied to determine the circumstances that foster increased

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

COMMUNITY ACTIVISM AND EDUCATION: ACCESS TO NEW KNOWLEDGE AS A BASIS FOR COMMUNITY EMPOWERMENT

113

community autonomy and decisionmaking power that translates into improved community health and well-being. ORGANIZATIONAL MODELS: HEALTH COMMITTEES AND NGOs To what extent can interested volunteers support and sustain the health of their communities in the face of an increasingly toxic environment? As a first step, there have to be sufficient health personnel, laboratories, and budget to respond to the threat of exposure to hazardous substances. Mexico provides an example where the direct participation of citizens is a real resource. In the small rural towns of Sonora, for example, there are voluntary groups called health committees. These health committees, which are organized by local health authorities but include community membership, have general oversight in matters pertaining to the running of the local health centers and their prevention programs. The committees, in general, have significant political clout with the regional health administrators; thus they can often exert sufficient pressure to obtain needed personnel and services. In many of the northern border cities of Mexico, NGOs also depend heavily on community volunteers. Although few are currently addressing the issue of lead poisoning in the region, NGOs provide a potentially useful mechanism for dealing with environmental hazards in a manner that can be useful to communities. the NGOs are often staffed by volunteers who act on behalf of their own and their neighbors' best interests. The question then becomes one of how to motivate community members to participate. COGNITIVE MODELS: POPULAR BELIEFS ABOUT LEAD Lead toxicity is a major problem in Mexico, as it is in every other country of the Americas. Whole neighborhoods in Tijuana, for example, are exposed to lead poisoning, and this has resulted in significantly lower IQ levels in grade school children living near the lead emission point sources (Guzmán, 1994). Of the children surveyed by Guzmán, 80 percent had blood lead levels that have been associated in cognitive studies with a seven-point performance IQ deficit, and the average blood lead of residents is higher than that associated with severe symptoms of lead poisoning. To date there has been no consistent public health response to the crisis of lead poisoning in Tijuana, nor has any effective community action been undertaken, in a large part because of a lack of community awareness about the hazards. For many in Tijuana, lead is invisible; for others, who may be aware of the hazards of lead, there is little knowledge about common routes

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

COMMUNITY ACTIVISM AND EDUCATION: ACCESS TO NEW KNOWLEDGE AS A BASIS FOR COMMUNITY EMPOWERMENT

114

of exposure, for example, lead-glazed ceramicware or local remedies for such maladies as stomach disorders that contain lead (Baer et al., 1989). Our study of community perceptions of lead as a health risk in Tijuana produced seven distinct and contrasting perspectives (see Box 3-1). These seven views demonstrate increasing knowledge of the dangers, and the nature and sources of community lead exposure.

BOX 3-1 SEVEN STAGES OF COMMUNITY PERCEPTIONS OF LEAD AS A HEALTH RISK, TIJUANA, MEXICO Stage 1. Belief: Lead does not exist. This stage was characteristic of community residents who had never experienced lead poisoning or been associated with someone who had. Stage 2. Belief: Lead exists as a metal; it has weight, texture, dimension and color. Familiar objects are made from lead. This stage was characteristic of persons living in marginal communities whose personal life experience includes the recognized use of lead objects. Stage 3. Belief: Lead exists both in its usual metallic forms and as an intangible substance in air, water, gasoline, soil, ceramics, paints, solder, or other entities. This stage was characteristic of a few of the more educated residents and of all high school students. Stage 4. Belief: Lead as a health hazard is recognized at higher levels of intoxication (80+ µg/dl). This level of knowledge was found among highly educated individuals, and uneducated individuals who have personally experienced the effects of lead-containing industrial waste. Stages 5 and 6. Belief: Lead as a toxic metal and its sequelae understood. This level reflects the knowledge of health providers and scientists in the community. Stage 7. Belief: Lead is a ubiquitous health problem. This level of knowledge was found among residents who articulated an understanding of the need to regulate lead and of the politics and complexities involved in doing so.

Adapted from Becker, 1974.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

COMMUNITY ACTIVISM AND EDUCATION: ACCESS TO NEW KNOWLEDGE AS A BASIS FOR COMMUNITY EMPOWERMENT

115

AN ACTION PLAN FOR INCREASING COMMUNITY COMPETENCE ABOUT LEAD HEALTH HAZARDS The preferred approach to developing strategies to reduce lead exposures is one that utilizes and is based on the capacities, skills, and assets of community members. Much of past public health experience demonstrates that significant advances in community health take place only when local community mentors are committed to investing themselves and their resources in the effort. Depending on its size and sophistication, a given community may have local institutions (such as businesses, schools, parks, libraries, hospitals, and colleges), citizens' associations (including churches, block clubs, and cultural groups), and gifted individuals (for example, artists, retired people, and young people) whose skills and knowledge can be used in the development of effective education and intervention. Specific steps for accomplishing these ends include: • Discovering the existence of active and trusted organizations or other resources within a community. These may include formal organizations (churches, government offices, and the like); informal organizations and networks (such as family and friends); or capacities and assets of individuals, citizens' associations, and local institutions; • Undertaking a community-led needs assessment that will allow residents to identify problems and priorities that are most important to them; this step should involve the building of productive relationships among local and state health networks who share the common goal of preventing lead poisoning; and • Identifying resource needs and the mechanisms to meet them.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

COMMUNITY ACTIVISM AND EDUCATION: ACCESS TO NEW KNOWLEDGE AS A BASIS FOR COMMUNITY EMPOWERMENT 116

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

117

CHAPTER 4

Working Group Summaries

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

118

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

WORKING GROUP SUMMARIES

119

WORKING GROUP SUMMARIES The conference featured six working groups. Each group focused on one of the following topics: gasoline; paint; ceramicware glazes; industrial and occupational health; food, water, and waste disposal; and techniques for improved lead surveillance and monitoring. Each working group was charged with identifying specific action steps that could be tailored by participants to regional, federal, or local needs, as required, to reduce human lead exposure in the hemisphere. The members of each working group met for six hours over a two-day period. The following statements summarize the deliberations and conclusions of the six groups.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

WORKING GROUP SUMMARIES 120

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

GASOLINE

121

WORKING GROUP I GASOLINE

MODERATOR: JACOBO FINKELMAN* RAPPORTEUR: ELLEN SILBERGELD**

Working group participants included representatives from government and the petroleum and other industries. The group summarized its deliberations according to the following construct: What to do:

Phase out lead in gasoline.

How to do it:

Restrict the use of lead by consensus regulation, while ensuring the appropriate supply of sufficient substitutes to meet octane requirements (without excess environmental impact).

Who is to do it:

Refining industry (private and public sector). Auto industry, by producing vehicles engineered to operate on unleaded fuels. Governments, by ensuring adequate inspection and maintenance and by providing subsidies for refining and price preferences for consumer purchasing of unleaded gasoline. Consumers, by demanding unleaded gasoline and avoiding misfueling with leaded gasolines.

What incentives:

“Supporting” refinery capacity, tax preference for unleaded gasoline, and subsidies for engine retrofit, if necessary.

What additional benefits could accrue, and for whom: Improved public image for the refining industry, as well as the ability to export in the world gas market; production of automobiles using nonleaded gasoline would provide potential products for the world market; improved health and food quality.

* Pan American Health Organization, Guatemala ** University of Maryland Medical School, Baltimore, Maryland, U.S.A.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

GASOLINE

122

DATA NEEDS The working group concluded that no further research on lead in gasoline as a source of environmental contamination or human exposure is needed. Nevertheless, members recommended compiling a database on the extent of production and use of leaded gasolines in the Americas. The following country and regional data would be essential to a useful database: • • • • • • • • •

permissible levels of lead in gasoline (national standards); actual use of lead in leaded gasoline; market allocation of leaded/unleaded gasoline (national and regional, by grade; as relevant); fuels refining capacity, total and by type of unit (barrels/day); other vehicle fuels in use, type and percent of market (ethanol, diesel, and the like); vehicle fleet (number, age, rate of change to new vehicles, performance, catalytic converter equipped); inspection and maintenance policies and practices for vehicles; price of fuels; trends in these factors. REDUCING LEAD ADDITIVES IN GASOLINE

The working group agreed that there is general progress toward the phasing out of tetraethyl/tetramethyl lead additives in gasoline in the Americas. Nevertheless, a national policy of lead reduction in motor fuels as a goal for air quality improvement requires considerably more information to be both effective and to achieve public acceptance. The motor vehicle fleet in a given country represents a range of octane requirements in the fuels that power it. This diversity in octane requirement arises largely from engine design, compression ratio, mileage accumulated (a more precise indicator for octane requirement than vehicle age), prior fuel usage history, maintenance level, and operator expectations of performance. Meeting this octane requirement usually involves a combination of unit refining processes that upgrade hydrocarbon molecules to those of higher octane value and the use of additives. Where the use of additives such as lead is restricted and there has been no adjustment in octane requirement, the burden falls heavily on the fuels refinery. Making up the difference involves capital expenditures, possible export and import issues, changes in the distribution system

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

GASOLINE

123

(additives can be blended in at many points, high-octane molecules normally only at the refinery), and a decrease in the efficiency of conversions of crude oil to motor fuel. The introduction of additives other than lead as an option to meet octane requirements was not endorsed by the working group. Some additives, such as those based on manganese or other metals, make their own contribution to air quality problems. Other additives, such as oxygenates, including alcohols and ethers, may produce tail pipe emissions that raise significant health questions when used in cars without catalysts. It is clear, therefore, that determining the rate of lead phasedown in motor fuels in a given country or region involves the interaction of many economic, technical, social, and demographic factors. There is also the one-time problem of purging an entire system for handling leaded fuels to be able to handle unleaded fuels. Of particular concern is the major task of cleaning the sludge from storage tanks that had been used for leaded gasoline. This sludge tends to be high in lead content; if it is not removed, can easily contaminate unleaded fuel introduced into the tanks. In an ideal configuration, capital investment by refiners and auto manufacturers, subsidies for conversion and retrofits, consumer education, clear enunciation of possibly conflicting goals, and realistic timetables should all be part of the decision process.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

GASOLINE 124

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

PAINT

125

WORKING GROUP II PAINT

MODERATOR: KATHRYN MAHAFFEY* RAPPORTEUR: DAVID JACOBS**

The United States is the only country in the hemisphere where lead-based paint has been clearly identified as a major source of childhood and occupational lead poisoning. While that has important lessons, it is impossible to extrapolate the experience of the United States to Canada, Mexico, the Caribbean Basin, or Latin America, because the current use and extent of lead-based paint cannot be reliably determined at this time. Each country of the Americas, however, has unique housing, infrastructure, and regulatory characteristics that must be understood before the context or use of lead-based paint can be determined. The working group developed recommendations on how to fill important data gaps. Only after these gaps have been eliminated can rational, cost-effective lead-based paint policies built on a firm scientific foundation be developed. The group found there was sufficient evidence in the United States and anecdotal evidence in other countries in the hemisphere to warrant two actions: • systematic collection of data; • certain preventive measures regarding current and future use. The working group noted during the plenary discussions that the Pan American Health Organization (PAHO) has already collected important data indicating that lead-based paint is an important potential source of lead poisoning throughout most of the Americas. In the United States, the U.S. Public Health Service regards leadbased paint, and the contaminated dust and soil it generates, to be the principal source of elevated blood lead levels in 1.7 million U.S. children between the ages of 1 and 5 years.

* Environmental Criteria and Assessment Office, U.S. Environmental Protection Agency, Cincinnati, Ohio, U.S.A. ** National Center for Lead Safe Housing, Columbia, Maryland, U.S.A.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

PAINT

126

Lead-based paint represents a difficult challenge after use because it is a source that is both highly concentrated and widely dispersed, necessitating control measures that are decentralized and relatively costly. Controlling leaded gasoline and lead in food and beverage cans, although difficult, is relatively simple compared with painted surfaces, because the source and associated control measures are generally more centralized. The working group determined that the extent of lead-based paint exposure could be analyzed by collecting data on the amount of: • • • •

lead used in the production of new paint (residential and commercial); old lead-based paint already existing in housing; lead-based paint used on toys, furniture, and other consumer items; lead-based paint used in nonresidential settings, principally bridges and other steel structures.

Two principal ways in which such data could be acquired are: • examination of production records, specifications, and import/export data, some of which have already been assembled by PAHO; • carefully designed field measurements of a small number of randomly selected representative housing units, steel structures, and consumer items to estimate the magnitude of lead-based paint as an exposure source in the country or region assessed. The working group felt that both strategies could be pursued simultaneously at relatively low cost. Field surveys provide information on lead present in paint already applied to surfaces, and production records and import-export data could be used to assess the extent of leaded paints currently in the marketplace. The working group recognized that the quality of records is likely to be highly variable, with many records incomplete or suspect. In designing field surveys, the working group concluded that it is essential to determine how the surveys are to be used and how small-scale pilot projects will be conducted. Preliminary assessment of the design of these pilot studies should be carried out by small focus groups. This would permit adaptation of survey designs to local conditions. Previous experience in the United States indicated that it is possible to design a survey of approximately 300 housing units to estimate the prevalence of lead-based paint hazards in an entire nation's housing stock, characterizing prevalence by region, kind of housing, age of housing, and type of building

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

PAINT

127

component coated with lead-based paint. Such survey findings have helped policymakers to formulate programs that were carefully targeted to make the wisest uses of scarce inspection and control resources. The implementation of field surveys should be done regionally or along national boundaries using already established measurement techniques. The surveys would need to be designed to account for variations, for example, in housing stock, cultural differences, geographic location, and ownership patterns. This effort should be considered a preliminary step in the development of a primary program aimed at source control. Primary prevention, however, cannot entirely replace secondary prevention (blood lead screening) or tertiary treatment of lead-poisoned persons. Failure to determine whether or not lead-based paint is an important source of exposure could lead to significant public health problems. The working group agreed that the decision to permit the widespread use of residential lead-based paint in the United States before 1978 has resulted in literally millions of cases of childhood lead poisoning and widespread lead poisoning in construction and housing rehabilitation and construction workers, as well as very serious economic pressures on affordable housing for the poor. Working group participants agreed that other countries in the hemisphere should develop policies and programs aimed at avoiding this experience by setting goals to prevent the use of lead-based paint, both in the residential and commercial settings. Members concluded that the International Labour Organization (ILO) treaty prohibiting the use of white lead in residential lead-based paints, signed by several countries in the 1920s, while visionary, did not generally lead to enforced regulations in the few Western Hemisphere signatories. The working group also agreed that it is important to estimate the presence of lead in other building materials, not just lead-based paint. The use of glazed tile as a floor and wall construction material, for example, suggests that new analytical methods may be needed, since current analytical methods are aimed at estimating ingestion of lead from glazes using leaching techniques. Little is presently known about the weathering or aging of lead-glazed tiles, although there is evidence that leaded dust on floors is among the strongest predictors of children's blood lead levels. Another building practice that should be examined is the use of scavenged waste materials, such as old battery casings or tires. The working group suggests that preliminary surveys can be carried out most cost-effectively by using portable X-Ray Fluorescence (XRF) lead-paint analyzers, which can screen many surfaces reliably, and relatively inexpensively. Laboratory-based paint chip testing techniques are likely

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

PAINT

128

to be far too expensive, while chemical spot-test kits are likely to be too unreliable to provide usable data. The group recognized that widespread implementation of lead-based paint surveys (either regionally or nationally) would require significant technical assistance and training, and this would require the collaboration of such entities as PAHO or the Centers for Disease Control and Prevention. Technical assistance of this kind has yielded benefits in Mexico, where lead-based paint prevalence was assessed in two neighborhoods. A technical manual on a variety of paint, soil, and dust sampling methods was also developed by the Pan American Health Organization (ECO/ OPS, 1995). Establishment of centers to train lead-based paint hazard inspectors, similar to those funded by EPA in the United States, would provide an important forum for manufacturers, public health professionals, housing personnel, and transportation professionals to interact to develop response measures, if surveys determine that lead-based paint use was, or is, widespread. Government purchasing authority should also not be ignored as a way of limiting the use of lead-based paint. The working group felt that a literature search of both published and unpublished studies on the distribution and extent of lead-based paints should be conducted, along with a review of occupational exposure data, to determine if building construction workers, painters, and workers in paint manufacturing facilities have had significant exposures to lead. Finally, the group noted that substitutes for lead-based paint are readily available for both residential and commercial uses at about the same cost, and that it would be far more costly to permit the continued use of leadbased paint, with the consequent hazard controls needed in later years. While such control measures have been shown to be effective in reducing children's blood lead levels, it would be far more inexpensive to avoid use of leaded paints in the first place. The U.S. government currently has grant programs totaling several hundred million dollars to abate and control lead-based paint hazards. Experience has shown that these expenditures would have been unnecessary had use of lead-based paint been proscribed in the first place. The working group recommended that new paint produced not contain more than trace amounts of lead-based paint (600 ppm in the dried paint film). Old, already applied paint should not exceed 5,000 ppm or 1 mg/cm2, although standards for each country may vary. In summary, the working group concluded that data on the prevalence of lead-based paint in the Americas is inadequate to determine if it constitutes a primary source of lead exposure. Specific steps should be taken to eliminate this data gap if rational control policies are to be developed.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

CERAMICWARE GLAZES

129

WORKING GROUP III CERAMICWARE GLAZES

MODERATOR: GUSTAVO OLAÍZ FERNÁNDEZ* RAPPORTEUR: MAURICIO HERNÁNDEZ-AVILA**

The group noted that there is little information published in scientific journals about the extent of use of lead-glazed ceramics (LGCs) in the Americas, nor is there epidemiologic data that would permit assessment of the importance of LGC as a source of human lead exposure in the Americas. For example, there are no data about the proportion of the glazed ceramic that leaches lead or about the numbers of people exposed to this source. Published information on the impact of the use of LGC on blood lead concentrations does exist for a few, select population samples in Mexico, the United States, and Canada. Levels of exposure appear to differ by country and sample studied. For example, LGCs appear to represent a minor problem in Canada and the United States, except for a number of Hispanic populations. In Mexico and Ecuador, LGCs are an important source of lead intoxication for large segments of the population. In these two countries, LGCs are part of cultural tradition and used by a large number of families. In Mexico City, for example, it is estimated that 30 percent of families cook and store food in LGCs with some regularity. The use of LGC is well-documented as an important source of lead for women of reproductive age in Mexico. In a study reported recently, women who used LGC for cooking and storage of foods had blood lead levels 3 µg/dl higher than a similar group that did not use LGC (Hernández-Avila et al., 1991). Also, other studies in Mexico have documented higher levels in children who live in households where food is prepared in LGCs (Romieu et al., 1995). For most countries in the region, there is no information about regular use of LGCs, and it is likely that use varies from country to country. In the United States and Canada, the working group noted that there is more information available about the risks associated with artisans' use of LGCs, and that these data have resulted in a decline in the use of lead glazes

* Environmental Health, Ministry of Health, Mexico City, Mexico ** Center for Public Health Research, National Institute of Public Health, Cuernavaca, Morelos, Mexico

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

CERAMICWARE GLAZES

130

in this sector. There is also evidence of a decline in the use of LGCs in Mexico. Given that this kind of ceramic has been used for many generations in Mexico and is strongly linked to tradition, however, producers and users still generally do not identify LGCs as a threat to health. Thus, adequate control of LGCs remains lacking. Mass information campaigns have not yet been developed in most countries of the Americas; where it has been attempted, work has been impeded by governmental institutions. Why is this? Working group members agreed that governmental and nongovernmental institutions in Mexico, for example, are opposed to mass campaigns for the public because they seek to protect those who make their living from production of LGCs. It is estimated that between 5,000 and 10,000 families would suffer economically from a decrease in public demand for LGCs. Also, cultural institutions are concerned that this tradition, which has existed in Mexico for many centuries, may disappear when consumers appropriately link LGC use to lead intoxication. In the United States and Canada, a more organized ceramic industry predominates, and this characteristic allows for a greater degree of consumer protection in these countries. In general, large and well-established industries are more likely to comply with legislative norms. Across the Americas, however, there are also artisans and artists who cannot comply with existing norms for economic reasons, and who also are not adequately informed of the risks involved. In such circumstances the working group recommends that frits –a fused or partially fused material used as a basis for glazes or enamels –containing lead be taken off the market or that the technique for use of lead-based frits not be included in the curriculum of schools that train in the ceramic arts. The working group recommends that there also be concerted attempts through education to minimize the recreational use of lead glazes by individual or home potters. In Latin America, producers of LGCs are predominantly microindustries, which are frequently family businesses in which the entire family is involved in the production process, and it is this householdwide participation that makes these industries economically viable. The involvement of family members in production activities and the high levels of lead contamination of the home environment seen in many instances, however, puts women and children at particular risk of chronic lead poisoning. One working group member noted that in a study carried out in communities involved in pottery production in Mexico, the highest concentrations of lead in blood were detected in women and children. Unfortunately, it was also reported that in these same communities, government interven

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

CERAMICWARE GLAZES

131

tions are generally distrusted for a variety of historical reasons. As a result, working group members concluded that home technologies would not prove successful initially. In addition, there is little possibility that this sector of the industry will comply with U.S., Canadian, or Mexican norms. For example, the cost of certifying that a product is lead-free in Mexico is higher than the price of the finished product; therefore, small-scale producers would not make a profit if mandatory lead testing were required. In any case, effective government regulation is unlikely to occur in Mexico. As in many other countries in Latin America and the Caribbean, artisans are geographically scattered and not easily accessible. Also, the markets in which many home products are sold are often in small, unregistered stores, which are typically mobile, and thus difficult to regulate. The working group concluded that even large-scale industries that produce LGCs in Latin America and the Caribbean Basin would be difficult to regulate because of a lack of adequate legislation; even more important is the absence of the human and physical infrastructure required to ensure compliance with established norms. The working group, therefore, recommended that increased attention and resources be directed toward developing the minimum core of laboratories and trained personnel in each country needed to help monitor the workplace safety standards that are established. In order to successfully reduce the manufacturing and use of LGCs across the Americas, the working group agreed that all interested or affected parties should participate in decisionmaking. Figure 4-1 lists the actors involved in ceramic production and some of the potential cross-sector interventions that could be applied. Several steps are required before substitution of lead-based frits can take place. As a first step, industries that produce lead frits should be contacted by public health authorities to evaluate the possibility of substituting lead with alternatives such as boron strontium and lithium. Lead frits are not an important source of revenue for these companies; therefore, economic incentives in the form of short-term industrial subsidies should be introduced into negotiations to stimulate a rapid transition to lead-free frits. A problem that may arise with the substitution of lead is that the current alternatives—boron strontium or lithium—may not work well under the fabricating conditions of most microenterprises or cottage industries. In these companies, ovens are often primitive and do not reach the temperatures required for the new materials to “take” (the low temperature compliance of lead is the main reason for its popularity as a glaze additive). Research is needed to better understand the possibilities of substitution

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

CERAMICWARE GLAZES

132

and to evaluate, under real conditions, the performance of potential alternatives. At the same time, the working group agreed that it is important for health educators to work with unions and artisans to increase their knowledge of lead and the health risks it poses to the worker, his family, and the consumers of his product.

Figure 4-1. Actors involved in the fabrication, commercialization, and use of ceramics. An additional point noted by the working group is that the substitution of alternative substances for lead creates a need to restructure the traditional modes of production, recognizing that past experiences in other domains has demonstrated that cultural traditions are very refractory to change. Several issues were raised in relation to the safety of the new alternatives. The working group agreed that research should be conducted to evaluate the safety of potential alternatives to lead by investigating the amount of the substance that can be expected to leach to food and its potential for negative health effects. The working group concluded that there is a need for interventions that guarantee the permanence of cultural values attached to LGCs and recognize the intrinsic value of the artisans' activity, yet promote a safe, lead-free product for consumers. These interventions should be carried out with the participation of all sectors involved, including public health institutions, artisans, government, and unions. Interventions identified for the short term include substitution of lead in the frits and, in the long run, the transfer of technology for the development of kilns that function at higher temperatures with the use of more efficient fuels.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

INDUSTRIAL AND OCCUPATIONAL HEALTH

133

WORKING GROUP IV INDUSTRIAL AND OCCUPATIONAL HEALTH

MODERATOR: ROBERT MCCONNELL* RAPPORTEUR: JULIETA RODRÍGUEZ DE VILLAMIL**

Working group participants agreed that in order to properly address the issues of lead in industrial and occupational health, it would be necessary to complete a preliminary inventory of industries and economic activities associated with occupational exposure to lead with a focus on Latin America and the Caribbean. The preliminary inventory prepared by the working group included manufacturers and recyclers of batteries; manufacturers of bronze articles; manufacturers of leaded cables; chemical operations; building demolishers; gasoline attendants; primary and secondary smelters; manufacturers of leaded ceramicware glazes and ceramics; manufacturers of bullets and lead-containing weapons; concerns that melt and cast leaded products; the jewelry trade; mining operations; manufacturers of steel; plumbers; industrial and house painters; stained-glass makers; manufacturers of leaded pigments; chimney cleaners; soldiers; shipbuilders; manufacturers of lead tetraethyl; manufacturers and repairers of radiators; automobile repair concerns; general construction operations; waste disposal concerns; artisans working with lead (religious figurines, lead soldiers); the plastics and metal industries; and manufacturers of refrigeration, lightbulbs (spotlights), and cosmetics. For each of these industries or occupational activities, it is necessary to consider the size of the company (large, medium, small, or micro-industry) in order to establish the following determinants of lead exposure: • • • •

intensity of exposure; number of workers exposed; trends in exposure; potential preventive and control activities, such as industrial hygiene.

* Pan American Center for Human Ecology and Health, Pan American Health Organization, Metepec, Mexico ** Occupational Health, Ministry of Health, Colombia

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

INDUSTRIAL AND OCCUPATIONAL HEALTH

134

Using estimates of lead exposure by occupational category and drawing from Dr. Isabelle Romieu's plenary presentation, “Prevalence of Exposure and Quality of Information,” the working group ranked the potential for lead poisoning among different categories of workers and identified needs for additional etiologic studies and intervention strategies for prevention and control in each case. As a first step, the working group agreed on the need to extend the preliminary survey conducted by Dr. Romieu and colleagues. Acknowledging the difficulties in collecting information on the extent and severity of lead poisoning in many countries of the Americas caused by a lack of existing data or data collection systems, the working group recommended that a national intersectoral group be organized in each country for the purpose of collecting requisite data in a consistent and ongoing manner. Data collection should be supported through country visits by international researchers with expertise in surveillance and monitoring of lead exposures in the population. The working group identified a number of potential strategies for reducing population lead exposures, with the following emerging as themes: • the substitution of lead in industrial processes and the reconversion of corresponding industries; • standardization or technical normalization of biological and environmental monitoring in the workplace; education and training in support of “the right to know, to participate, to transparency”; • the necessity of technical support to implement prevention and control activities in industrial hygiene, infrastructure of occupational health, communication of risk, and human resources; • provision of incentives, training, and financing for standardized research on prevention and control of lead poisoning across the Americas; • improvement of conditions of work in microindustries and reduced paraoccupational exposure to lead; • expansion of training of experts in occupational health in order to strengthen human resources, especially in the Caribbean Basin and Latin America. The working group concluded that reducing occupational exposure to lead will require the involvement and commitment of a broad range of players, including government, employers, workers, unions, and nongovernmental organizations (NGO's).

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

INDUSTRIAL AND OCCUPATIONAL HEALTH

135

Government should design and implement national and international occupational health policies in order to control or eliminate lead exposures. In some countries of the hemisphere, legislation in support of the fulfillment of norms and regulations will require modernization of the workplace in accordance with the developmental stage of that country. National governments should provide the financial support necessary to encourage industrial control or elimination of lead exposures. Lead exposure reduction in the industrial sector should be a priority in discussions with international donors. The working group recommended that government also provide adequate health care for workers exposed to lead; it was recognized that an organized strategy is required to support stepby-step modification of the structure of occupational health services and other relevant, longer-term occupational health objectives. The working group agreed strongly that employers must assume the responsibility of risk resulting from worker exposure to lead. Members recommended that employers organize occupational health services that include, for example, blood screening, protective equipment, and areas to wash hands to control exposure to lead in the work environment. It was also felt that it is the role of the employer to ensure better health and work conditions for workers, even in instances where lead cannot be substituted in the workplace. In addition, it is the responsibility of individual employers to follow regulations and standards controlling exposure and the use of lead. Working group members acknowledged that workers also have a role in ensuring the safety of their workplace. For example, workers should be willing to collaborate with employers in the implementation of rules for controlling exposure, including accepting and adopting safe places to work with lead. It is the responsibility of the individual to comply with the recommended preventive measures, to avoid unsafe habits and lifestyles—for example, cigarette smoking—and prevent paraoccupational exposure of lead within the family. Unions should educate their workers to ensure that these responsibilities are fulfilled. NGOs can assist in this process by communicating the risks of working with lead through training of exposed workers, their employers, and the community in general. All actors and sectors involved should guarantee the sufficient availability and allotment of human and financial resources to allow for alternative solutions to lead where they exist. A Job Exposure Matrix that ranks occupational settings on the basis of the extent of lead exposure should be developed to guide occupational prevention, control,

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

INDUSTRIAL AND OCCUPATIONAL HEALTH

136

and monitoring activities. Special attention should be given to the evaluation of these programs with respect to their success in preventing or controlling occupational lead exposures. The working group recommends development of standardized occupational and environmental policies on lead poisoning prevention that are standardized across the Americas. Policies should be directed toward primary prevention, identification, and timely treatment of lead poisoning when it occurs, and toward appropriate compensation for cases of incapacitation from lead poisoning. Industries should also guarantee relocation or retraining of lead-poisoned workers as needed. The following are general conclusions and recommendations of the working group: • Government, in alliance with workers and employers, should develop the capability to monitor the health of workers (and their families) in small and microindustries where lead is utilized; • International standards for surveillance and monitoring, worker safety training, and laboratory quality control should be developed and applied in all countries of the hemisphere; • National and international campaigns should be developed in order to increase awareness of the adverse effects of lead on health and of the benefits of prevention and control. One example might be the creation of a “World Lead Day;” • Interventions for handling workers exposed to lead should include options for retirement, job relocation after the withdrawal of the exposure, and adequate compensation in case of disability; • Workers as well as employers have a responsibility to implement and maintain a safe workplace.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

FOOD, WATER, AND WASTE DISPOSAL

137

WORKING GROUP V FOOD, WATER, AND WASTE DISPOSAL

MODERATOR: LEN RITTER* RAPPORTEUR: TANIA TAVARES**

This working group profited from the contribution of representatives from industry, government, academia, nongovernmental organizations, and trade unions from five different countries of the Americas. The pathways of lead contamination of water and food are multiple and interrelated. Strategies to reduce lead exposure through these pathways will, therefore, require interrelated solutions. WATER The main sources of lead contamination in water identified by the working group were: lead in water pipes and plumbing fixtures; residue from lead shot in rivers, lakes, wells, and other outdoor sources of drinking water; industrial and lead pesticide runoff; leaching from industrial and urban landfills where lead-containing wastes (such as batteries and paint) are dumped; deposition from atmospheric emissions deriving from leaded fuel and industrial activities; and social practices such as the collection of rainwater for drinking in high-density traffic or industrial areas. Remediation through addition of phosphate to water sources, a common intervention, was considered useless as it merely changes soluble lead into particle form, which can be ingested as well. The new practice in Japan of lining old lead pipes with plastic tubing was brought to the attention of the group, but there are yet insufficient data on the cost-effectiveness of this method to warrant a recommendation for adoption. FOOD The main sources of lead in food are leaded solder in food cans; lead glazes used on foodware; leaded fuel and industrial emissions that can reach food

* Canadian Network of Toxicology Centres, Ottawa, Ontario, Canada ** Federal University of Brazil, Salvador, Bahia, Brazil

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

FOOD, WATER, AND WASTE DISPOSAL

138

from atmospheric dry and wet deposition, contaminated irrigation water, or lead-contaminated soil; and leaded pesticides. The extent of information on the distribution and use of leaded pesticides in the Americas was viewed as extremely limited. The working group, therefore, did not focus discussion on this source. It did, however, recommend that attempts be made to determine the importance of leaded pesticides as a source of lead poisoning in the hemisphere. STRATEGIES The working group focused on identification of strategies to reduce lead exposure from food, water, and waste sources. Four strategies that have proven successful in one or more countries of the region were identified in the hope that they may be adopted by other countries of the hemisphere. • The first strategy involves elimination of lead solder in canned foods through replacement of lead-soldered joints with electrically welded joints. Canning industries in Mexico and the United States that have refitted accordingly have realized the following benefits: a 3–5 percent reduction in raw materials, resulting from the smaller welded joint; no net additional costs from retooling, because materials costs most often offset equipment costs; a smaller welded joint provides a larger surface area for advertising; a decreased risk of liability; and potential for increased market share. The working group concluded that to be successfully undertaken in most countries of the Americas, this initiative requires support from both industry and government in the form, for example, of government subsidies available to the manufacturer, legislative regulation, and enforcement. • The second strategy is directed toward the elimination of lead in fuels. This, in turn, will reduce lead contamination of air, food, and water. The working group did not address this issue in depth, given that it was the focus of another working group. • The third strategy is targeted toward reduction of point source lead emissions, including cottage industries. The working group felt that initial progress toward this end could be achieved first through an inventory of such potential sources. Strategies for reducing lead exposures from specific categories of sources could then be addressed as a first option by collaborative alliances among industry, government, community-based action groups, and labor unions. Involvement of

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

FOOD, WATER, AND WASTE DISPOSAL

139

industry in source inventory and identification of potential solutions will help encourage industry to follow through on reduction, abatement, and remediation measures. The incentives for industry to participate in this process are improved public image, decreased liability costs, increased market share, and long-range economic gains. The working group recommends that support for involvement of the necessary multiple players should come from industry, government (through subsidies, legislation and enforcement, technical support, and information), the Pan American Health Organization, the World Bank, foundations, and other NGOs. • The fourth strategy to reduce exposure to lead in food and water is by improving household family practices (domestic hygiene). The working group concluded that the responsibility for reducing lead exposures in the home environment lies with the community itself, specifically the individual households. The extent and effectiveness of domestic hygiene practices could be increased through community and individual education, local empowerment (that is, “train the trainer”), and widespread implementation of such practices as handwashing, peeling food, sweeping and cleaning of the house at regular intervals, and not collecting rainwater for drinking in lead-lined containers. Local health units and levels of government, community organizations, NGOs, and charitable foundations should be encouraged to develop and provide these public education programs to increase awareness of the hazards of lead and knowledge of effective preventive measures.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

FOOD, WATER, AND WASTE DISPOSAL 140

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

TECHNIQUES FOR IMPROVED SURVEILLANCE AND MONITORING OF LEAD EXPOSURE

141

WORKING GROUP VI TECHNIQUES FOR IMPROVED SURVEILLANCE AND MONITORING OF LEAD EXPOSURE MODERATOR: HENRY FALK* RAPPORTEUR: HOWARD FRUMKIN**

The working group participants agreed on the conventional definition of public health surveillance as applied to lead: the systematic, ongoing collection, analysis, and dissemination of information on lead exposure or lead toxicity, with the ultimate goal of preventing toxicity. The following were identified as important factors in surveillance programs: • Surveillance is important, not for its own sake, but to provide information to support prevention. The goals of surveillance programs may vary depending upon local needs and priorities. In any case, goals should be set at the beginning of the program and may include case-finding, monitoring population trends, evaluating the efficacy of interventions, generating data to persuade policymakers, and education. • Both biological sampling and environmental sampling may be important components of lead surveillance programs. Traditional public health approaches have relied heavily on biological sampling; because lead enters the body through various routes that may be difficult to measure, and lead absorption, even at low levels, requires prompt medical and public health response, biological sampling continues to be a mainstay of lead surveillance. This is the case-finding function. In addition, biological sampling helps to evaluate the success of prevention efforts and to monitor overall population trends. Environmental sampling may be equally or even more appropriate in some circumstances, however, and is often overlooked, particularly for monitoring sources of lead exposure. When resources are scarce, careful consideration should be given to the relative importance of each approach.

* Division of Environmental Hazards and Health Effects, Centers for Disease Control and Prevention, Atlanta, Georgia, U.S.A. ** Department of Environmental and Occupational Health, Rollins School of Public Health, Atlanta, Georgia, U.S.A.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

TECHNIQUES FOR IMPROVED SURVEILLANCE AND MONITORING OF LEAD EXPOSURE

142

• It is essential to target surveillance to the greatest extent possible given search resources in most countries of the Americas. For biological sampling, high-risk populations should receive priority. For environmental sampling, environments with a high probability of substantial lead exposure should receive priority. The working group discussed results from the recent NHANES III (National Health and Nutrition Examination Survey) in the United States, and although members praised the precision and generalizability of the results, they agreed that a general population survey like NHANES would not currently be a high priority in most countries of the Americas because of cost and feasibility. In contrast, the members agreed that occupationally exposed populations, communities with exposure to point sources, communities with other high-level exposures (such as to lead-containing ceramics), and susceptible subpopulations such as children and pregnant women should be a high priority for lead surveillance. The choice of a population or potential exposure to be targeted may be made based on various kinds of information, such as screening questions, published literature on patterns of lead use, and information from previous surveillance. • There is a critical need to provide more laboratories and train technical personnel throughout the countries of the Americas. During the workshop, Dr. Robert Jones of the Centers for Disease Control described the CDC lead testing proficiency program, which is free to participating laboratories. Dr. Henry Falk, also of the CDC, discussed possible CDC support for training laboratory personnel in at least one lead testing facility in each country or subregion of the Americas. Perhaps this could be combined with outside support, if available, for the acquisition of lead testing equipment in these labs. This effort might be coordinated by the Pan American Health Organization. • Successful surveillance programs should be simple and inexpensive, and to the extent possible should take advantage of existing programs and facilities. For example, lead testing might be added to programs that test children for other health conditions, or laboratory-based reporting might be required. • Lead surveillance programs need certain guidelines and procedures to function efficiently and equitably. Examples discussed in the workshop included reference levels for lead in food, water, and other media; in the occupational setting, workers who are tested must be guaranteed that their medical confidentiality will be protected, and that the finding of an elevated blood lead level will result in removal from exposure,

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

TECHNIQUES FOR IMPROVED SURVEILLANCE AND MONITORING OF LEAD EXPOSURE

143

treatment if necessary, and maintenance of wages, but in no case dismissal or retribution; and in both the environmental and the occupational setting, any surveillance program must include provisions for follow-up of elevated blood lead levels, including removal from exposure, treatment if necessary, and abatement of an ongoing hazard. • Surveillance programs provide an invaluable opportunity for education of people exposed to lead. It is essential to link education with surveillance. Surveillance programs, while often planned and implemented by specialized public health personnel, should involve other health care providers in planning, implementation, interpretation of results, and follow-up actions. Groups of special importance in this regard are practicing pediatricians; occupational health physicians; and state, local, and provincial public health authorities. .

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

TECHNIQUES FOR IMPROVED SURVEILLANCE AND MONITORING OF LEAD EXPOSURE 144

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

145

Appendixes

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

146

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX A

147

APPENDIX A REFERENCES

Abbritti, G., G. Muzi, T. Fiordi, M. P. Accatoli, P. Morucci, F. A. Bauleo, and F. Blasi. 1992. Increased lead absorption in children living in an area with high concentration of ceramic workshops. Med. Lay. 83(6):576-586. ACGIH (American Conference of Governmental Industrial Hygienists). 1991. Documentation of the threshold limit values and biological exposure indices. 6th ed. Cincinnati, Ohio: American Conference of Governmental Industrial Hygienists. Alliance to End Childhood Lead Poisoning and EDF (Environmental Defense Fund). 1994. The Global Dimensions of Lead Poisoning: An Initial Analysis. Washington, D.C.: Alliance to End Childhood Lead Poisoning. Annest, J.L. 1983. Trends in the blood lead levels of the U.S. population: The Second National Health and Nutrition Examination Survey (NHANES II) 1976-1980. Pp. 33-58 in Lead Versus Health, M. Rutter and R.R. Jones, eds. New York: John Wiley & Sons. Arias Torres, E., R. Oropaza Monterrublo, D. Aguilar Jeronimo, A. Chilpa Naverrete, and G. Espinosa Chavarria. 1990. Contaminación por Plomo en la Industria Alimentaria. Informe Tecnico del IPN. ATSDR (Agency for Toxic Substances and Disease Registry). 1988. The Nature and Extent of Lead Poisoning in Children in the United States: A Report to Congress. DHHS Report 99-2966. Atlanta, Ga.: CDC, U.S. Department of Health and Human Services, Public Health Service. ATSDR (Agency for Toxic Substances and Disease Registry). 1992. Case Studies in Environmental Medicine: Lead Toxicity. Atlanta, Ga.: CDC, U.S. Department of Health and Human Services, Public Health Service. Azar, A., R. D. Snee, and K. Habibi. 1975. An epidemiologic approach to community air lead exposure using personal air samplers. Lead (Suppl. 2) 2:254-288.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX A

148

Barry, P. S., and D. B. Mossman. 1970. Lead concentrations in human tissues. Brit. J. Med. 27 (4):339-351. Bayley, N. 1969. Bayley Scales of Infant Development. New York: The Psychological Corporation. Baer, R. D., J. García de Alba, L. M. Cueto, A. Ackerman, and S. Davison. 1989. Lead based remedies for empacho: Patterns and consequences. Soc. Sci. Med. 29(12):1373-1379. Baghurst, P. A., A. J. McMichael, S. Tong, N. R. Wigg, G. Vimpania, and E. Robertson. 1995. Exposure to environmental lead and visualmotor integration at age 7 years: The Port Pirie Cohort Study. Epidemiology 6(2):104-109. Baker, E., et al. 1977. Lead poisoning in children of lead workers. N. Engl. J. Med. 296(5):260-261. Barltrop, D., and H. Khoo. 1975. The influence of nutritional factors on lead absorption. Postgrad. Med. 51(601):795-800. Becker, M.H (ed). 1974. The health belief model and personal health behavior. Health Educ Monogr 2:324-508. Bellinger, D. 1995. Neuropsychologic function in children exposed to environmental lead [Editorial]. Epidemiology 6(2):101-103. Bellinger, D. C., H. L. Needleman, A. Leviton, C. Waternaux, M. B. Rabinowitz, and M. L. Nichols. 1984. Early sensory development and prenatal exposure to lead. Neurobehav. Toxicol. Teratol. 6(5):387-402. Bellinger, D., A. Leviton, H. L. Needleman, C. Waternaux, and M. Rabinowitz. 1986. Low-level lead exposure and infant development in the first year. Neurobiol. Toxicol. Teratol. 8(2):151-161. Bellinger, D., A. Leviton, C. Waternaux, H. Needleman, and M. Rabinowitz. 1987. Longitudinal analyses of prenatal and postnatal lead exposure and early cognitive development. N. Engl. J. Med. 316(17):1037-1043. Bellinger, D., J. Sloman, A. Leviton, M. Rabinowitz, H.L. Needleman, and C. Waternaux. 1991. Low-level lead exposure and children's cognitive function in the preschool years. Pediatrics. 87(2):219-227. Benetou-Maranditou, A., S. Nakou, and J. Micheloyannis. 1988. Neurobehavioral estimation of children with life-long increased lead exposure. Arch. Environ. Hlth. 43(6):392-395. Bidwell, E. S. 1988. Health for all: The way ahead. World Health Forum 9(1):37-45. Brody, D. J., J. L. Pirkle, R. A. Kramer, K. M. Flegel, T. D. Matte, E. W. Gunter, and D. C. Paschal. 1994. Blood lead levels in the United States population. JAMA 272(4):277-283.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX A

149

CDC (U.S. Centers for Disease Control and Prevention). 1991. Preventing Lead Poisoning in Young Children: A Statement by the Centers for Disease Control. Atlanta, Ga.: CDC, U.S. Department of Health and Human Services. Chia, K. S., and D. Koh. 1992. Health education and health promotion at the workplace. Pp. 432–449 in Occupational Health in Developing Countries, J. Jeyaratnam, ed. New York: Oxford University Press. Christoffersson, J. O., L. Ahlgren, A. Schutz, S. Skerfving, and S. Mattsson. 1986. Decrease of skeletal lead levels in man after end of occupational exposure. Arch. Environ. Hlth. 41(5):312-318. Cikrt, M. 1990. Environmental health research in Czechoslovakia: A brief overview. Pp. 129–132 in Proceedings of the Symposium on Occupational and Environmental Health during Societal Transition in Eastern Europe, Environment and Health in Eastern Europe, Pécs, Hungary, June 22-27, 1990, B. S. Levy and C. Levenstein, eds. Boston: Management Sciences for Health. Coste, J., L. Mandereau, F. Pessione, M. Bregu, C. Faye, D. Hemon, and A. Spira. 1991. Lead-exposed workmen and fertility: A cohort study on 354 subjects. Eur. J. Epid. 7(2):154-158. East African Regional Programme on Occupational Health and Safety. 1991. Final Report. Finnish Institute of Occupational Health, Helsinki. ECO/OPS (Centro Panamericano de Ecología Humana y Salud/Organizacíon Panamericano de la Salud). 1995. Manual de Procedimiento en la Toma de Muestras Biológicas y Ambientales para Determinar Niveles de Plomo, T. Carreón Valencia, L. López, Carrillo and I. Romieu, eds.. México: ECO/OPS. EDF (Environmental Defense Fund). 1992. The Hour of Lead. Washington, D.C.: EDF. EIA (Energy Information Administration). 1992. The Motor Gasoline Industry: Past, Present and Future. DOE/EIA Publication No. 0539. Washington, D.C.: U.S. Government Printing Office. EPA (U.S. Environmental Protection Agency). 1973. Regulation of fuels and fuel additives: Control of lead additives in gasoline. Fed. Reg. 38(234):33734-33741. EPA (U.S. Environmental Protection Agency). 1978. National primary and secondary ambient air quality standards for Lead. Fed. Reg. 43 (194):46246-46261. EPA (U.S. Environmental Protection Agency). 1982a. Regulation of fuels and fuel additives. Fed. Reg. 47(167):38070-38078.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX A

150

EPA (U.S. Environmental Protection Agency). 1982b. Regulation of fuels and fuel additives. Fed. Reg. 47(167):38078-38089. EPA (U.S. Environmental Protection Agency). 1982c. Regulation of fuels and fuel additives. Fed. Reg. 47(210):49322-49334. EPA (U.S. Environmental Protection Agency). 1984. Regulation of fuels and fuel additives. Fed. Reg. 49(150):31032-31049. EPA (U.S. Environmental Protection Agency). 1986. Air Quality Criteria for Lead, EPA-600/8-8-33/028aF, vols. 1–4 . Research Triangle Park, N.C.: Environmental Protection Agency, Environmental Criteria and Assessment Office. Fee, E. 1990. Public health in practice: An early confrontation with the ‘Silent Epidemic' of childhood lead paint poisoning. J. Hist. Med. Allied Sci. 45(4):570-606. Fergusson, D. M., L. J. Horwood, and M. T. Lynskey. 1993. Early dentine lead levels and subsequent cognitive and behavioral development. J. Child Pscyhol. Psychiatr. 34(2):215-227. Freire, P. 1973. Education for critical consciousness. New York: Seabury. Frumkin, H. In press. Medical treatment of lead toxicity. Am. J. Ind. Med. Goldstein, G. W. 1990. Lead poisoning and brain cell function. Environ. Hlth. Perspect. 89:91-94. Goyer, R. A. 1990. Lead toxicity from overt to subclinical to subtle health effects. Environ. Hlth. Perspect. 86:177-181. Grandjean, P., T. Lyngbye, and O. Hansen. 1991. Lessons from a Danish study on neuropsychological impairment related to lead exposure. Environ. Hlth. Perspect. 94:111-115. Grant, L. D., and J. M. Davis. 1989. Effects of low level lead exposure on paediatric neurobehavioral development: current findings and future directions in lead exposure and child development: An International Assessment, M. A. Smith, L. D. Grant, and A. I. Sors, eds. Boston: Kluwer Academic. Guzmán Perez, J. M. 1994. Contaminacion y conducta: efectos del plomosobre la comprension verbal. Talk presented at the Primer Simposio de Investigacion Aplicada en Salud Ambiental y Laboral en las Californias 9-11 de June, 1994. Colegio de la Frontera Norte, Tijuana, B.C. Hansen, O. N., A. Trillingsaard, I. Beese, T. Lyngbye, and P. Grandjean. 1989. A neuropsychological study of children with elevated dentine lead levels: Assessment of the effect in different socioeconomic groups. Neurotoxicol. Teratol. 11(3):205-213.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX A

151

Hernández-Avila, M., I. Romieu, C. Rios, A. Rivero, and E. Palazuelos. 1991. Lead-glazed ceramics as major determinants of blood lead levels in Mexican women. Environ. Hlth. Perspect. 94:117-120. Hernberg, S. 1988. Lead. In Occupational Medicine, C. Zenz, ed. Chicago, Ill.: Mosby. Hernberg, S. 1995. Five decades of research for the benefit of workers' health. Newsl. Finnish Inst. Occupational Hlth. Special Issue:4-6. Hertz-Picciotto, I. and J. Croft. 1993. Review of the relation between blood lead and blood pressure. Epidemiol. Rev. 15(2):352-373. Hong, S., J. P. Candelone, C. C. Patterson, and C. F. Boutron. 1994. Greenland ice evidence of hemispheric lead pollution two millennia ago by Greek and Roman civilizations. Science 265(5180):1841-1843. ILO (International Labour Organization). 1921. International Convention No. 13 on White Lead (Painting). Geneva: ILO. Jiménez, C., I. Romieu, E. Palazuelos, I. Muñoz, M. Cortés, A. Riero, and J. Catalán. 1993. Factores de Exposición Ambiental y Concentraciones de Plomo en Sangre en Niños de la Ciudad de México [Environmental exposure factors and the concentration of blood lead in Mexico City children]. Salud Publica Mex. 35(6):599-606. Johnson, N., and K. Tenuta. 1979. Diets and lead blood levels of children who practice pica. Environ. Res. 18:369-376. Kahema, H., and R. Monyo. 1990. Lead exposure in battery manufacturing factory in Tanzania—A Case Study. E. Afr. Newsl. Occup. Hlth. Saf.Suppl 1:72-74. Kaloyanova, F. 1991. A perspective from Bulgaria. Pp. 114–121 in Proceedings of the Second Annual Symposium on Environmental and Occupational Health during Societal Transition in Central and Eastern Europe, Air Pollution in Central and Eastern Europe, Health and Public Policy, Frydex-Mistek, Northern Moravia, Czechoslovakia (CSFR), June 14–19, 1991, B. S. Levy, ed. Boston. Mass.: Management Sciences for Health. Kazantzis, G. 1989. Lead: Ancient metal—modern menace? Pp. 119–129 in Lead Exposure and Child Development: An International Assessment, M. A. Smith, L. D. Grant, and A. L. Soris, eds. London: Kluwer Academic. Kurppa, K., W. D. O. Sakari, A. W. Wambugu, A. S. Mubisi, J. Rantanen, and M. Tuppurainen. 1985. Research on occupational health problemsin Kenyan industries: Diseases caused by calcined diatomite, asbestos, cotton, and lead. Pp. 76–109 in Proceedings of the First ILO-Finnish-

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX A

152

Tanzanian Symposium on Occupational Health, M. Tuppurainen and K. Kurppa, eds. Helsinki: Finnish Institute of Occupational Health. Lancrajan, I., H. I. Popescu, O. Gavanescu, et al. 1975. Reproductive ability of workmen occupationally exposed to lead. Arch. Environ. Hlth. 30:396-401. Landrigan, P. J. 1988. Lead: Assessing its health hazards. Hlth. Environ. 2(6):1-3. Landrigan, P. J. 1989. Toxicity of lead at low dose. Brit. J. Indust. Med. 46(9):593-596. Lara-Flores, E., J. Alagón-Cano, J. Bobadilla, B. Hernández-Prado, and A. Ciscomani-Begoña. 1989. Factores Asociados a los Niveles de Plomo en Sangre de Residentes de la Ciudad de México [Factors associated with the blood levels of lead in residents of Mexico City]. Salud Publica Mex. 31(5):625-633. Leung, H. W. 1988. Environmental sampling of lead near a battery reprocessing factory. Bull. Environ. Contam. Toxicol. 41(3):427-433. Mahaffey, K. 1981. Nutritional factors in lead poisoning. Nutr. Rev. 39(10):353-362. Mahaffey, K. 1990. Environmental lead toxicity: Nutrition as a component of intervention. Environ. Hlth. Perspect. 89:75-78. Matte, T., J. P. Figueroa, G. Burr, J. Flesch, R. Keelyside, and E. Baker. 1989a. Lead exposure among lead-acid battery workers in Jamaica. Am. J. Ind. Med. 16(2):167-177. Matte, T., J. P. Figueroa, S. Ostrowski, G. Burr, L. Jackson-Hunt, R. Keenlyside, and E. Baker. 1989b. Lead poisoning among household members exposed to lead-acid battery repair shops in Kingston, Jamaica. Intl. J. Epidemiol. 18(4):874-881. Matte, T., J. P. Figueroa, S. Ostrowski, G. Burr, L. Jackson-Hunt, and E. Baker. 1991. Lead exposure from conventional and cottage lead smelting in Jamaica. Arch. Environ. Contam. Toxicol. 21(1):65-71. Miller, R. K., and D. Bellinger. 1993. Metals. In Occupational and Environ mental Reproductive Hazards: A Guide for Clinicians, M. Paul, ed. Baltimore, Md.: Williams and Wilkins. Muñoz, I., I. Romieu, E. Palazuelos, T. Mancilla-Sanchez, F. Meneses-Gonzalez, and M. Hernández-Avila. 1993. Blood lead level and neurobehavioral development among children living in Mexico City. Arch. Environ. Hlth. 48(3):132-139. National Center for Lead-Safe Housing. 1995. Does Residential Lead-Based Paint Hazard Control Work? A Review of Scientific Evidence. Columbia, Md.: National Center for Lead-Safe Housing.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX A

153

NRC (National Research Council). 1972. Lead: Airborne Lead in Perspective. Washington, D.C.: National Academy Press. NRC (National Research Council). 1980. Lead in the Human Environment. Washington, D.C.: National Academy Press. NRC (National Research Council). 1993. Measuring Lead Exposure in Infants, Children and Other Sensitive Populations. Washington, D.C.: National Academy Press. NRDC (Natural Resources Defense Council). N.d. Global Phase-Out of Leaded Gasoline by the Year 2000. Washington, D.C. NRDC (Natural Resources Defense Council) and CAPE 21 (Consortium for Action to Protect the Earth). 1994. Four in ‘94: Focus on Two Years after Rio. Washington, D.C.: Earth Summit Watch Report. Needleman, H. L. 1988. The persistent threat of lead: Medical and sociological issues. Curr. Probl. Pediatr. 18(12): 697-744. Needleman, H. L., ed. 1992a. Human Lead Exposure. Boca Raton, Fla.: CRC. Needleman, H. L. 1992b. Childhood lead poisoning: Man-made and eradicable. PSQR 2:130-134. Needleman, H. L., and C. A. Gatsonis. 1990. Low level lead exposure and the IQ of children: A meta-analysis of modern studies. JAMA 263 (5):673-678. Needleman, H. L., et al. 1979. Deficits in psychologic and classroom performance of children with elevated dentine lead levels. N. Engl. J. Med. 300(13):689-695. Nriagu, J. O. 1990. The rise and fall of leaded gasoline. Sci. Total Environ. 92:13-28. Nriagu, J. O., and J. M. Pacyna. 1988. Quantitative assessment of worldwide contamination of air, water and soils by trace metals. Nature 333 (6169):134-139. Nunez, C. M., S. Klitzman, and A. Goodman. 1993. Lead exposure among automobile radiator workers and their children in New York City. Am. J. Ind. Med. 23(5):763-767. OECD (Organization for Economic Cooperation and Development). 1994. Lead risk reduction monograph. Paris: OECD. Olaíz Fernández, G., T. Fortoul van der Goes, and R. Rojas Martinez. 1995. La Alfareria en México: El Arte del Barro Vidriado y Plomo. In Intoxicación por Plomo en México: Prevención y Control. Instituto Nacional de Salud Pública. Departamento del Districto Federal. México, 1995. OSHA (U.S. Occupational Safety and Health Administration). 1993. Interim final standard for lead in construction. Fed. Reg. 58:26590-26649.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX A

154

Palazuelos E. Plomo y Salud: Impacto Ambiental de la Reformulación de las Gasolinas en la Zona Metropolitano de la Ciudad de México: Una evaluación economica. Estudio solicitado por la comisión Metropolitano para la prevención y control en el valle de México. Noviembre de 1993. Phoon, W. O., et al. 1985. Health services and welfare of workers in small-scale Singapore enterprises. Pp. 116–122 in Proceedings of the 11th Asian Conference on Occupational Health, B. Reverente, ed.. Manila, Philippines: ACOH. Piomelli, S., J. Rosen, J. Chisholm, and J. Graef. 1984. Management of lead poisoning. J. Pediatr. 105(4):523-532. Pirkle, J., D. J. Brody, E. W. Gunter, R. A. Kramer, D. C. Paschal, K. M. Flegel, and T. D. Matte. 1994. The decline in blood lead levels in the United States. JAMA 272(4):284-291. Pocock, S. J., D. Ashby, and M. A. Smith. 1987. Lead exposure and children's intellectual performance. Intl. J. Epidemiol. 16(1):57-67. Rabinowitz, M. B., G. W. Wetherill, and J. D. Kopple. 1976. Kinetic analysis of lead metabolism in healthy humans. J. Clin. Invest. 58:260-270. Rabinowitz, M. B., J. D. Wang, and W. T. Soong. 1991. Dentine lead and child intelligence in Taiwan. Arch. Environ. Hlth. 46(6):351-360. Repko, J. D., C. R. Corum, P. D. Jones, and L. S. Garacia, Jr. 1978. The Effects of Inorganic Lead on Behavioral and Neurologic Function. NIOSH/DHEW Publication No. 78-128. Washington, D.C.: U.S. Government Printing Office. Riwa, P., and L. J. Kitunga. 1990. Blood lead levels in selected factories in Dar es Salaam. E. Afr. Newsl. Occup. Hlth. Saf. Suppl 1:94-95. Rom, W. 1976. Effect of lead on the female and reproduction: A review. Mt. Sinai J. Med. 43:542-552. Romieu, I., E. Palazuelos, F. Meneses, and M. Hernández-Avila. 1992. Vehicular traffic as a determinant of blood lead levels in children: A pilot study in Mexico City. Arch. Environ. Hlth. 47(4):246-249. Romieu, I., E. Palazuelos, M. Hernández-Avila, C. Rios, I. Muñoz, C. Jimenez, and G. Cahero. 1994. Sources of lead exposure in Mexico City. Environ. Hlth. Perspect. 102(4):384-389. Romieu, I., T. Carreon, L. Lopez, E. Palazuelos, C. Rios, Y. Manuel, and M. Hernández-Avila. 1995. Environmental urban lead exposure and bloodlead levels in children of Mexico City. Environ. Hlth. Perspect. 103(11):2.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX A

155

Ruiz Sandoval, G. 1878. Higiene Pública: Envenenamiento Lento por el Plomo en los Habitantes de Oaxaca. Gaceta Médica de México 13 (21):393-403. Sakari, W. D. O. 1990. Blood lead concentrations in small-scale industries in Nairobi. E. Afr. Newsl. Occup. Hlth. Saf. Suppl 1:96. Saryan, L. A., and C. Zenz. 1994. Lead and its compounds. In Occupational Medicine, third ed., C. Zenz, O. B. Dickerson, and E. P. Horvath, eds. St. Louis, Mo.: Mosby–Year Book. Schwartz, J. 1991. Lead, blood pressure, and cardiovascular disease in men and women. Environ. Hlth. Perspect. 91:71-75. Schwartz, J., and R. Levin. 1991. The risk of lead toxicity in homes withlead paint hazards. Environ. Res. 54:1-7. Shannon, M. W., and J. W. Graef. 1992. Lead intoxication in infancy. Pediatrics 89(1):87-90. Silbergeld, E. K. 1991. Lead in bone: Implications for toxicology duringpregnancy and lactation. Environ. Hlth. Perspect. 91:63-70. Silbergeld, E. K. 1992. Mechanisms of lead neurotoxicity: or looking beyond the lamppost. FASEB J. 6(13):3201-3206. Silbergeld, E. K. 1995. International dimensions of lead exposure. Intl. J. Occup. Environ. Hlth. 1(4):336-348. Silbergeld, E. K., H. S. Adler, and J. L. Costa. 1977. Subcellular localization of lead in synaptosomes. Res. Commun. Chem. Pathol. Pharmacol. 17(4):715-725. Silbergeld, E. K., P.J. Landrigan, J. R. Froines, and R. M. Pfeffer. 1991. The occupational lead standard: A goal unachieved, a process in need of repair. New Solutions 1(4):20-37. Silva, P. A., P. Hughes, S. Williams, and J. M. Faed. 1988. Blood lead, intelligence, reading attainment, and behaviour in eleven-year-old children in Dunedin, New Zealand. J. Child Psychol. Psychiatr. 29(1):43-52. Silvany-Neto, A. M., F. M. Carvalho, M. E. C. Chaves, A. M. Brandao, and T. M. Tavares. 1989. Repeated surveillance of lead poisoning among children. Sci. Total Environ. 78:179-186. Smith, C. M., X. Wang, H. Hu, and K. T. Kelsey. 1995. A polymorphism in the δ-aminolevulinic acid dehydratase gene may modify the pharmacokinetics and toxicology of lead. Environ. Hlth. Perspect. 103(3):248-253. SOEH (Society for Occupational and Environmental Health). 1993. Protecting Workers and Their Communities from Lead Hazards: A Guide for Protective Work Practices and Effective Worker Training. McLean, Va.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX A

156

Steenhout, A. 1982. Kinetics of lead storage in teeth and bones: An epidemiological approach. Arch. Environ. Hlth. 37:224-231. Stiles, K. M., and D. C. Bellinger. 1993. Neuropsychological correlates of low lead exposure in school age children: A prospective study. Neurotoxicol. Teratol. 15(1):27-35. Sussell, A., ed. In press. Means to Reduce Hazardous Occupational Lead Abatement Exposures. Cincinnati, Ohio: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health. Tackett, S. 1987. Lead in the environment: Effects of human exposure. Am. Clin. Prod. Rev. (May):14-18. United States Department of the Interior, Bureau of Mines. 1994. Mineral Commodity Summaries, January. Washington, D.C.: U.S. Department of Interior. United States Department of the Interior, Bureau of Mines. 1995. Mineral Commodity Summaries, January. Washington, D.C.: U.S. Department of Interior. Valkonen, S. 1995. Kemikaalialtistumisen biomonitorointi [Biological Monitoring of Chemical Exposures]. Helsinki: Biomonitoring Laboratory, Finnish Institute of Occupational Health. Watanabe, H., H. Hu, and A. Rotnitzsky. 1994. Correlates of bone and blood lead levels in carpenters. Am. J. Ind. Med. 26(2):255-264. Wedeen, R. P. 1994. Poison in the Pot. Carbondale: Southern Illinois University Press. WHO (World Health Organization). 1977. Environmental Health Criteria 3: Lead. Geneva: WHO. Yankel, A. J., I. H. Von Lindern, and S. D. Walter. 1977. The Silver Valley Lead Study: The relationship between childhood lead poisoning and environmental exposure. J. Air Pollut. Control Assoc. 27(8):763-767.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX B

157

APPENDIX B POSTER PRESENTATIONS

Alameda County Lead Poisoning Prevention Program (ACLPPP ): Community Education and the Role of Community Health Outreach Workers. Rebecca Carrillo and Dario Hunter(1). (1)Oakland, California, U.S.A.. Alameda County is both ethnically and economically diverse, requiring a multifaceted approach to the prevention of childhood lead poisoning. ACLPPP's outreach and education focuses on paint, dust, and soil as primary sources of lead toxicity in children. Ceramics fired at low temperatures and home remedies in the Latino community are also focal points. The outreach component of the program is dedicated to increased community awareness of lead hazards, potential dangers of lead poisoning, and increased screening for children. This is accomplished, in part, by providing outreach both to and through several subcommunities, including the local medical community; local schools (K-12); day care centers; renovators; and targeted neighborhoods based on exterior conditions of homes. Strategies for reaching families include, but are not limited to, educational home visits or phone contact for children with elevated blood lead levels, door-to-door campaigns, informational booths, health fairs, public service announcements, community presentations, informational potlucks, an informational line, and promotional items. Alliance to End Childhood Lead Poisoning: International Action Plan for Preventing Lead Poisoning. Maria Rapuano(1), K.W. Rochow(1). (1)Washington, D.C., U.S.A. The Alliance to End Childhood Lead Poisoning, a nonprofit interest organization formed in October 1990, focuses exclusively on eliminating lead poisoning. Its mission is to frame the agenda, formulate innovative approaches, and bring critical resources to bear –scientific and technical knowledge, public policy, economic forces, other organizations, and community leaders– to prevent lead poisoning. In 1994 the Alliance convened The Global Dimensions of

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX B

158

Lead Poisoning: The First International Prevention Conference in Washington, D.C., bringing together over 250 advocates, officials, and experts from every continent, with substantial representation from developing countries. The conference used for discussion The Global Dimensions of Lead Poisoning: An Initial Analysis prepared by the Alliance and the Environmental Defense Fund. In April 1995, the Alliance released its most recent report, International Action Plan for Preventing Lead Poisoning, providing a framework for taking the actions needed to reduce and eliminate lead poisoning. Phasing lead out of gasoline is one of the single most effective steps that can be taken to prevent lead poisoning. The phaseout campaign, conducted by the Alliance in concert with other nongovernmental organizations (NGOs), is based on the framework for lead poisoning prevention embodied in the International Action Plan. Blood Lead Levels According to Branch of Industrial Activity: September 1992-September 1994. Carmen Yris Delgado Pantaleón(1), Angel Danilo Moquete(1). (1)Pan American Health Organization, Santo Domingo, Dominican Republic. We analyzed the occupational exposure and the blood lead levels of workers exposed to lead in various industries in the Dominican Republic. We looked at the workers most directly affected by lead who had clinical manifestations of lead poisoning, a history of exposure, and a confirmation of exposure from laboratory results. Of the 1,429 workers studied, 348 had blood lead levels that exceeded the acceptable limits set by the World Health Organization (40 µg/dl). Lead levels were lowered through the implementation of recommendations given to the industries to control the lead exposure. In addition, a diagnostic approximation of the principal sources of lead exposure in the formal sector and their effects on the health of the exposed population were obtained. Blood Lead Levels of Workers Exposed to Leaded Gasolines and Combustion Products in Trinidad. Ivan Chang-Yen(1), Neela Pooransing(1), David Bratt(2), Anthony Parkinson(2), Leverson Boodlal(3). (1)The University of West Indies Chemistry Dept., (2)University of West Indies Medical School, (3)Ministry of Workers and Transport, Trinidad. Studies of blood lead levels of motor vehicle mechanics, exhaust repair workers, and road maintenance personnel were carried out in Trinidad. The mean blood lead level of a local control population over a similar age range was simultaneously determined for comparison. Persons in

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX B

159

the former groups had mean blood lead levels two to three times higher than that of the control population. Of particular interest was the finding that persons residing in close proximity to motor vehicle repair sites also had mean blood lead levels significantly higher than that of the controls. Work habits, the use of leaded gasolines in Trinidad, and air and roadside dust concentrations are used to explain the results obtained in the groups studied. The need for strategies to minimize such exposures was also discussed. Childhood Lead Poisoning Prevention: Yesterday, Today, and Tomorrow in the Far West. L. Rex Ehling(1), Alvaro Garza(1). (1)California Department of Health Services, Childhood Lead Poisoning Prevention Branch, Emeryville, California, U.S.A.. This poster offers reflective and prospective views of childhood lead poisoning and its prevention in the United States, specifically in California. The display reviews what we have learned about the effects of lead on various organ systems; the accumulation of lead hazards in the environment; a review of regulatory efforts both nationwide and in California; epidemiology of the disease in California; and California's plan to eliminate childhood lead poisoning based upon primary, secondary, and tertiary prevention models. Community Action and the Reduction of Lead Exposure: The Trail Experience. Terry Oke(1). (1)Trail Lead Program, Trail, Canada. Trail, a small city of 9,000 people in the province of British Columbia, Canada, has a lead/zinc smelter, active since the turn of the century. Contamination from stack and fugitive emissions has resulted in a significant health concern for young children. A health study in 1989 found that the geometric mean blood lead level of Trail area children was 13.1 µg/dl. The Trail Community Lead Task Force has responsibility for reducing children's blood lead levels and producing a remedial strategy for the community. Trail uses community input as an approach to remedial decisionmaking. Since 1990, comprehensive programs of blood lead screening, community education, and case management, as well as investigations of lead exposure pathways and intervention, have assisted the Task Force in achieving its mandate. Controlling Lead Exposure due to “Backyard” Battery Repair Shops in Jamaica. J. Peter Figueroa(1), Thomas Matte(1), Stephanie Ostrowski(1), et al. (1)Jamaican Ministry of Health Epidemiology Unit, Kingston, Jamaica. Reports of Jamaican children being admitted to hospitals with severe

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX B

160

lead poisoning led to an investigation of the problem in the mid-1980s. Three surveys were undertaken: (1) 58 households were studied in the Red Pond community in which an established lead smelter and several cottage lead smelters were located; (2) 3 battery manufacturers and 10 battery repair shops were surveyed and 69 workers tested; (3) 24 households in Kingston with exposure to “backyard” battery repair shops (BBRS) were surveyed. Soil lead levels in Red Pond exceeded 500 parts per million (ppm) in 24 percent of households, and 44 percent of children under 6 years of age had blood lead levels exceeding or equal to 25 µg/dl. Proximity to backyard smelters and to the conventional smelter were independent predictors of soil lead, which was the strongest predictor of lead in children under 12 years of age. Sixty-five percent of “backyard” battery repair shop workers and 28 percent of battery manufacture workers had lead levels above 60 µg/dl. The majority of households (84 percent) with exposure to BBRS had soil lead levels above 500 ppm, and 43 percent of children under 12 years of age in these households had lead levels greater than 70 µg/dl. The findings of the three surveys were used to mobilize efforts to reduce the high lead exposure levels in the different settings. Persons with abnormally high lead levels were removed from exposure points and treated. The media highlighted the serious nature of the problem, and the findings were shared with the management and the workers of the battery repair shops and the community and the household members. An educational program was put into place, specific control measures identified, and inspection visits increased. The conventional smelter in Red Pond closed down and clean-up was undertaken. The control measures have resulted in a significant decrease in pediatric admissions for lead poisoning. Additional measures are needed to further reduce lead exposure arising from backyard battery repair shops (Matte et al., 1989a, 1991). The Development of A Statewide Database on Lead-Safe Housing and Identifying Communities with High Risk of Lead Poisoning. Robert Haug(1), Joan Cook Luckhardt(2). (1)New Jersey Department of Community Affairs, (2)University of Medicine and Dentistry of New Jersey, New Jersey, U.S.A.. The United States permitted lead in residential paint until 1978; as a result, over five million metric tons of lead remain on dwellings throughout the country. The Department of Community Affairs, Lead-based Paint Abatement Program and Division on Codes and Standards, and Lead Poisoning Prevention Education and Training Program at the

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX B

161

University of Medicine and Dentistry of New Jersey SOM have been developing a pilot registry of lead-safe housing using Geographic Information Systems to identify areas with high risk of lead exposure and cataloguing lead-safe dwelling units. The registry will provide citizens with information to help them avoid renting or buying homes with unacceptable lead hazards. Information from all municipal building permits on all lead abatement activities and gut rehabilitation projects and other publicly funded programs requiring lead removal will be entered to create the lead-safe housing registry. Other state demographic and geographical databases also are used. Addresses of lead-safe houses will help tenants seeking lead-safe housing and agencies placing lead-burdened children with minimal disruption. Educational Interventions to Change Head Start Parents' Behavior to Prevent Lead Poisoning Among Young Children. Cecile Dickey(1), J. C. Luckhardt(2), Fred Patterson(3), Frank Torpey(4). (1)St. Peters College, Jersey City, New Jersey, (2) New Jersey Head Start Assoc. and University of Medicine and Dentistry of New Jersey, (3)Fred Patterson Assoc. and Johnson & Johnson Co., New Jersey, (4)Ethicon Corporation, New Jersey. The Johnson and Johnson Corporation and the New Jersey Head Start Association are designing educational materials and interventions to educate about the dangers of lead poisoning and are developing ways to better prevent lead poisoning in 2,000 Head Start Children in four New Jersey cities using control and experimental groups. The modes of intervention include outreach workers educating individual families, use of broadcast media and print materials, and small group instruction. The effectiveness of the various modes of education will be assessed by an independent research institute with interviews conducted before, during, and after the program. Blood lead levels of the children in the experimental and control groups will be measured before and after the educational intervention. Effect of a Nutritional Intervention to Reduce Lead Exposure in Infants. M. Hernández-Avila(1), I. Romieu(2), E. Palazuelos-Rendón(3), E. Fishbein(1), L. H. Sanin(1), S. Treviño(1). (1)National Institute of Public Health, Cuernavaca, Mexico, (2)Pan American Center for Human Ecology and Health, Mexico, (3)Federal District Department, Minister of the Environment, Mexico. The effect of a nutritional intervention to reduce lead exposure in infants is currently being studied in Mexico City. This double-blind, placebo-controlled study will assess whether a supplement

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX B

162

of 1,200 mg of calcium given to lactating mothers with elevated lead levels in breast milk will reduce lead absorption in their nursing infants. Recruitment for the study is conducted antepartum, but the study begins immediately postpartum. Mothers are randomly placed in either treatment or placebo groups according to blood lead levels (high or low). The mothers are contacted for follow-up on three separate occasions. The first contact is one month after delivery in the hospital ABC investigation center, where biological samples of mother's blood, urine, milk, and bone, and samples of the baby's blood (if the mother allows) and hair are taken. Information on the mother's socioeconomic status, daily practices leading to potential lead exposure (for example, ceramicware use), anthropometric data, and daily dietary calcium intake are gathered during interviews. The first dose of calcium or placebo is given at this time. The second contact is made at the mother's home four months after delivery, and the same biologic samples (excluding bone and the baby's blood) are taken. The second and final dose of calcium or placebo is given at this time. Seven months after delivery, a final contact is made. Biologic samples (excluding the baby's blood) are taken, and diet is reassessed. A parallel intervention designed to educate mothers about lead poisoning prevention and breastfeeding advantages was also conducted monthly with approximately 50 percent of the mothers. The promotion project started in November 1994 and will end in June 1995. Because the study is still under way, conclusions and findings are not available. The study will examine the relationships between maternal calcium intake and lead levels in nursing infants and between maternal lead levels and the following factors: use of glazed ceramics, living in high-density traffic zones in Mexico City, length of time residing in Mexico City, type of water used for drinking, kind of paint used in the home, partner's and mother's job, mother's usual smoking habits, and mother's education and socioeconomic level. Epidemiological Analysis of Lead Exposure in Four Different Occupations. Nancy Patiño Reyes(1). (1) District Secretary of Health, Bogota, Colombia. Workers exposed to lead from four different occupations were identified and their blood lead levels assessed in the city of Santafé de Bogota. The occupational groups were (1) service station attendants, (2) printers, (3) painters, and (4) battery factory workers. The analyses were conducted with a hematoflurometer to determine zinc protoporphyrin (ZPP) as a method of screening, verifying some samples with atomic absorption spectrophometry (AAS) equipped with a graphite furnace to

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX B

163

test the accuracy and reliability of this method. The results showed that the battery workers had the highest blood lead levels of the four occupational groups. Families Exposed to Lead: A Public Health Problem. Nancy Patiño Reyes(1). (1)District Secretary of Health, Bogota, Colombia. Children of workers who live near battery factories are at risk of being exposed to residual lead brought home by the workers. A 2-year-old girl, whose parents worked in a battery factory, died in May 1993 from lead poisoning. This death, and several other cases of extremely poisoned children in the same population, precipitated the need to study the syndrome of “fouling the nest.” Arrangements are under way for such studies. There are other families in the region exposed to lead from the religious elements and images they make and sell. Blood lead levels in these individuals have been reported to be as high as 900 µg/dl. Programs of intervention have been targeted to these families. Fouling the Nest with Lead: The Santo Amaro Case Study. Fernando M. Carvalho(1), Annibal M. Silvany-Neto(1), Tania M. Tavares(1). (1)Federal University of Bahia, Bahia, Brazil. From 1960 to December 1993, a primary lead smelter, a branch of a multinational company producing 11,000 to 32,000 tons of lead a year, polluted Santo Amaro City, State of Bahia, Brazil. Average blood lead levels of the 642 children living within 900 meters of the industry were 59.1 µg/dl in 1980, decreasing to 36 µg/dl in 1985 after abatement measures were taken. About 22 percent of the study population were children of smelter workers. Smelter dross was freely donated by the industry to local populations, who often used it to pave the backyards and orchards of their homes. Geometric mean of zinc protoporphyrin (ZZP) in children living in homes where dross was present was 78.8 µg/dl, whereas this concentration was 70.3 µg/dl for children in dwellings without dross. The enterprise, a branch of a multinational company, has moved to another state of Brazil because it could not cope with the health and environmental penalties levied against it. Their legacy now includes 230 unemployed workers, some with health problems; an unknown number of people poisoned by lead; and about 500,000 tons of smelter dross containing 1-3 percent lead scattered around the former smelter area. This episode illustrates the poor compliance with environmental and occupational regulations by the industry and the lax enforcement of these laws by the state authorities.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX B

164

Lead Content in Tropical Vegetables and Fruits Grown Around a Smelter. M. Bereta(1), V. P. Campos(1), T. Tavares(1). (1)Department of Analytical Chemistry, Federal University of Bahia, Brazil. Levels of lead in 25 varieties of consumer vegetables and fruits at various distances upwind and downwind from a smelter, within a 12-kilometer radius, were determined. Lead content in soil where crop plants were grown and in atmospheric particles was also measured. Plant samples were pretreated in the manner customary in the local consumer population, and lead was then extracted with concentrated nitric acid in Teflon-lined pressure vessels for 15 hours. Atmospheric particles were collected and fractionated by size with a 6-stage Berner impactor, then extracted with nitric acid in an ultrasonic bath. Analysis was conducted by atomic absorption spectrophometry with a graphite furnace. Highest levels (µg/g-dry weight basis) were found in green vegetables: mint (23-1,109), coriander (11-436), lettuce (17-406), green cole (5-394), and okra (22-12). Based on local eating habits, however, PTWI will most probably be exceeded because of consumption of homemade mint tea or of local dishes based on okra and green cole. These higher lead levels are associated more with fugitive emissions from the smelter than chimney emissions or soil lead content. Lead-free Glazes in Ceramic Production. Mario Lugardo Covarrubias Perez(1). (1)Naucalpan, State of Mexico, Mexico. The use of nonleaded glazes in Santa Maria Canchesda, Municipality of Temascalzingo, Mexico, was implemented. The following are highlights of the program: • Nonlead enamels, their application, and use in traditional pottery for holding food and beverages were instituted. • Ceramic colors without lead were applied, controlled, and used in pottery. • The use of energetic fusings to lower the fusion temperature of the nonlead ceramic glazes was initiated. • The use of frits—a fused or partially fused material used as a basis for glazes or enamels—began. • New production methods for raising the pottery production were used. • Alternative decoration methods in pottery production were tried. • Government institutions interested in the development of new ways to solve the problem of lead in the pottery were consulted. • Technical, administrative, and countable training was begun.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX B

165

National Lead Information Center. Janet Phoenix(1). (1)Washington, D.C., U.S.A. In 1992 the Environmental Health Center of the National Safety Council established the National Lead Information Center under a cooperative agreement with the U.S. Environmental Protection Agency (EPA) and with support from four federal agencies—EPA, Department of Housing and Urban Development, Centers for Disease Control and Prevention, and the Department of Defense. The National Safety Council/National Lead Information Center's lead-related activities include co-sponsorship, with EPA, of a national education campaign intended to raise public awareness about lead poisoning. The National Lead Information Center has three primary activities: a national toll-free hotline (1-800-LEAD-FYI); an information clearinghouse (1-800-424-LEAD); and focused education and outreach activities. The hotline, which opened in November 1992, provides callers with a packet of easy-tounderstand materials about lead poisoning prevention. The clearinghouse provides information on how to most effectively manage, avoid, and, if necessary, mitigate potential lead-related health risks. Occupational Blood Lead Trends in Manitoba, 1979 through 1994: Assessing the Effectiveness of Regulation and Surveillance. Annalee Yassi(1), Ted Redekop(2), Norma Alberg(2), Mary Cheang(1). (1)University of Manitoba, (2)Manitoba Department of Labor, Manitoba, Canada. Between 1979 and 1994, as part of regulated occupational surveillance, an analysis was conducted of 16,199 blood lead samples from employees of 9 high-risk workplaces in Manitoba, Canada. Results from workers in radiator shops were also analyzed beginning in 1986. A significant decrease in blood lead concentrations was observed overall, as well as for each of the high-risk companies. Longitudinal analyses by individual worker suggested that companies were complying through use of administrative controls—that is, removing workers to lower-lead areas until blood lead levels had fallen, then returning them to high-lead areas. In 1987 an order was issued requiring removal of the worker at blood lead levels of 2.42 µmol/L (50 µg/dl) or higher, as well as limiting environmental exposure to 50 µg/m3. This resulted in a significant reduction in the number of workers with blood lead levels exceeding 50 µg/dl. Focusing on blood lead as the sole criterion for compliance proved ineffective. Regulations must specifically require environmental monitoring and controls, with biological surveillance serving as “back-up” to ensure effectiveness of these efforts.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX B

166

Occupational Exposure to Lead According to Altitude. René Córdova Cardozo(1). (1)National Department of Occupational Medicine, La Paz, Bolivia. A clinical survey was undertaken of 29 workers exposed to lead, of whom 13 were treated with the chelation d-penicillamine, and 16 were not chelated. These workers were employees of a metallurgical factory located between 3,800 and 4,000 meters above sea level. Lead-exposed workers showed the following signs of intoxication: “lead lines” in teeth and gums (n= 23); reduced muscle strength in upper arms and legs (14); intestinal colic (11); dizziness and loss of memory (11); and decreased libido (8). In accordance with industrial exposure classifications, these workers were labeled “dangerously exposed.” It was observed that in 30 percent of the workers there were signs of anemia, porphyrinurea, and nephrotoxicity, which were correlated with blood and urine lead concentrations. In these workers, it is important to consider the interactions of nutritional status with prolonged lead exposure. It is possible that lead exposure at high altitudes may have different effects than at sea level because of differences in respiratory parameters. If this is the case, exposure standards may need to be reevaluated. Protection Against Consumption of Lead During Pregnancy Through the Consumption of Milk and Orange Juice: The Case of Mexico City. L. H. Sanin(1), M. Hernández-Avila(1), I. Romieu(3), F. G. Olaíz(2), E. Palazuelos-Rendón(4), R. Tapia(1). (1)Center for Public Health Research, National Institute of Public Health, Mexico, (2)Director General of Environmental Health, Mexico, (3)Pan American Center for Human Ecology and Health, Mexico, (4)Federal District Department, Minister of the Environment, Mexico. A total of 1,849 binomials (mother and child) were studied to assess if there is protection offered by the consumption of milk and orange juice on blood lead levels in the mother-child binomial. The maternal mean age was 25 years. Blood samples were taken at the moment of childbirth in nine gynecogenic/obstetrics hospitals of Mexico City between 1992 and 1993. The study included only women with normal pregnancies and childbirths. The lead content in the maternal venous blood and umbilical cord was measured, and questions assessing exposure to the most widely acknowledged sources of lead in Mexico City were asked of the mothers. Maternal blood lead levels (MBL) ranged between 0.5 and 58.3 µg/dl, with a geometric mean of 10.63. No important variation by social class, age group, or marital status was found. The umbilical cord blood lead values varied between 0.40 and 55.2 µg/dl, with a geometric mean of 10.17. Regression analysis of umbilical cord lead

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX B

167

and MBL produced a B value= 0.7363, the correlation between both values was r= 0.743. The main predictor of maternal blood lead was the use of glazed earthenware; MBL was inversely correlated with consumption of milk and orange juice. It is the first time that the protectiveness of foodstuffs rich in calcium and in which calcium has great bioavailability is proved with empirical data from such a population group. Reducing Sources of Lead Exposure Through Community Education. Joan Cook Luckhardt(1), Stacey Kenyon(1). (1)University of Medicine and Dentistry of New Jersey, Stratford, New Jersey, U.S.A.. In 1991, 1,110,000 tons of the 1,250,000 tons of lead consumed in the United States were used to make rechargeable leadacid batteries (such as car batteries). Each car battery contains about 18 pounds of lead. Improper disposal of lead-acid batteries can result in incineration or dispersal of lead on the surface of the earth. Local and state government and industry developed a comprehensive recycling program for batteries. To increase consumer recycling of all spent rechargeable batteries, the University of Medicine and Dentistry of New Jersey, in cooperation with the New Jersey Department of Environmental Protection, has designed a battery recycling campaign and a pre- and postcampaign survey of public knowledge and behavior. The public information campaign includes public service announcements, posters, flyers, training videos, mailings to all vehicle owners in the state, training manuals for hazardous waste and recycling coordinators, and community-based educational programs in each county. Each county's hazardous waste coordinators are responsible for separation and proper storage and transport of batteries to approved and monitored secondary smelters. Educational materials were developed with focus groups. The pre- and postcampaign survey tested public knowledge about lead and citizen responsibility for environmental protection. The project is a model of how to link various levels of government and form private-public partnerships to reduce toxins in the environment. Regulation and the Reduction of Lead in California: Proposition 65. David Roe(1). (1)Environmental Defense Fund, Oakland, California, U.S.A.. Remarkable progress in reducing the amount of exposure to lead from a variety of consumer products has been made in California. Examples include removing leaded glazes and leaded paints from a full range of commercial ceramicware in thousands of patterns manufactured in numerous countries; ceasing the use of leaded brass and leaded bronze in the manufacture of submersible well pumps throughout the United

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX B

168

States; advancing the use of lead-leaching barriers in the manufacture of fine and medium-range crystalware (for example, decanters and wine glasses); and adding warnings and use instructions to the use of home lead casting equipment (such as lead-melting pots and molds for the casting of bullets, lead sinkers) through an innovative law known as Proposition 65. Regulation and the Reduction of Lead in Gasoline in the United States. Judith MacGregor(1), Howard Mielke(2). (1)San Diego State University, California, (2)Xavier University, Louisiana, U.S.A.. The addition of leaded additives to gasoline as antiknock agents and octane enhancers grew steadily as the use of automobiles increased in the United States from 1923 to its peak in the late 1960s, when more than 450 million pounds (205 million kilograms) of lead were used in gasoline additives annually. Even though it was estimated that 85 percent of the lead in air in the United States was derived from gasoline combustion, the use of leaded fuels continued. In order to achieve the emission goals for hydrocarbons and carbon monoxide in the Clean Air Act, catalytic converters were required on new automotive exhaust systems in 1973, and unleaded gasoline was essential to avoid fouling the emission equipment. The decline in blood lead levels measured in a national survey of the general population paralleled the decline in the use of leaded fuels. Lead reservoirs still exist from past use. Lead levels in the urban soils parallel the density of automotive use, and contaminated soil persists, continuing as a source of lead exposure. In addition, lead stored in bone deposits will take many years to deplete, with 40–70 percent of current blood lead levels derived from bone stores. Relationship Between Blood Lead in Children and Lead Mining Activities. Ana Maria Murgueytio(1), R. Gregory Evans(1). (1)St. Louis University School of Public Health, St. Louis, Missouri, U.S.A.. We evaluated blood lead levels in children living in southwestern Missouri, in one of the world's largest lead-zinc mining areas. The 240-square-mile site is on the United States Environmental Protection Agency list of priority hazardous waste sites. Data indicate that 14 percent of 243 children between 6 and 71 months of age living in the area of lead mine exposure had blood lead levels greater than 10 µg/dl. None of the 138 children living in a comparison area had elevated levels. Soil lead levels were six times higher and dust lead levels three times higher in the exposed compared with the comparison area, 599 ppm compared with 91 ppm for soil, and 609 ppm compared with 209 ppm for dust. The study concluded that soil lead levels were primarily responsible

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX B

169

for the difference in blood lead levels between the two groups. A number of behavioral and socioeconomic factors were also associated with elevated blood lead levels. Risk Factors Associated with High Blood Lead Levels in Mexico City Schoolchildren. F. G. Olaíz(1), M. R. Rojas, T. I. Fortoul(2), C. R. Tapia, M. Doyer(3), E. Palazuelos-Rendón(4). (1)Director General of Environmental Health, Mexico City, (2)Professor, UNAM, (3)Director General of Epidemiology, (4)Federal District Department, Minister of the Environment, Mexico City, Mexico. Between April 1991 and May 1992, blood lead concentrations were analyzed in 1,583 schoolchildren who resided in five areas: two with historically high blood lead concentrations (Xalostoc and Tialnepantla) and three with historically low concentrations of the metal in the air (Pedregal, Centro, and Iztapalapa). The selected schools were located less than 5 kilometers from the RAMA monitors. A questionnaire including information about lead exposure risk factors was presented to the parents. Bivariate and multilogistic analyses were conducted to evaluate the strength of the association and identify the most accurate model to explain the variability of the blood lead sample concentrations. The highest values were found in children who lived in Xalostoc and Tialnepantla (16.7 and 16.4 µg/dl respectively), and the lowest values were observed in children living in Iztapalapa (9.26 µg/dl). The most significant predictive variables were: place of residence (p = 0.001), the use of glazed pottery for cooking meals (p = 0.003), chewing playdough (p= 0.005), eating paint chips from the walls (p = 0.003), and failing school years since the beginning of the primary school (p = 0.02). There was no correlation of either age or gender with blood lead concentrations. Substitution of Leadless Ceramic Glazes. Michael McCann(1). (1)Center for Safety in the Arts, New York, New York, U.S.A.. The use of lead-containing ceramic glazes has resulted in lead poisoning of both potters and their families, and of people eating and drinking from ceramicware. In the United States and Canada, substitution of leadless ceramic glazes using boric oxide, alkaline, and alkaline earth fluxes has become common. This trend has been accelerated by strict laws regulating how much lead can leach from ceramicware used for eating and drinking containers. There are several problems involved in the substitution of leadless glazes. Tradition has to be overcome, because leadless glazes often do not give the effect expected by potters. Lead-free glazes require different and more careful firing conditions. Active communication among potters has

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX B

170

been a major factor. There is also an environmental problem with the potential lead-contamination of kilns and the cost of substitute materials compared with lead batteries and other easily available materials currently in use. Factors that can help overcome these problems will include increased awareness of the lead poisoning issue among potters and their families and the economic incentive of a larger market in the United States and elsewhere for leadless ceramicware. United Parents Against Lead: Parents United to Educate A Nation United We Can Save A Rainbow of Children. Maurci Jackson(1). (1)Chicago, Illinois, U.S.A.. United Parents Against Lead (UPAL) is a national organization of and for parents of lead-poisoned children. It works to end the continuing threat of lead poisoning through education, advocacy, resource referral, and legislative action. Founded in 1994, UPAL is committed first and foremost to ensuring the basic right of all children to live in a safe and healthy environment. Our members come from diverse backgrounds, reflective of the broad range of communities affected by lead, but we are united by our unique experience and commitment. We know firsthand the effects of lead poisoning and the irreparable damage and suffering caused by this preventable epidemic. As parents, we have a responsibility to bring our children's voices and experiences to the national dialogue and to remind participants that children's health and safety are fundamentally everyone's responsibility. UPAL assists parents in organizing chapters in states and local communities and is committed to assisting affected families. Members are kept informed of local, state, and national developments through the publication of our national newsletter. Accurate information is a crucial element in the campaign to eliminate this disease. UPAL promotes proactive steps to prevent children's exposure instead of parents “learning after the fact.” We want to ensure that other families do not needlessly repeat our experiences. Whether a family is African-American, white, Asian, or Hispanic, whether they live in the suburbs, inner cities, or in rural areas, parents need information that will empower them to make informed decisions. We aim to provide that information. Using Benefit-Cost Analysis to Build Alliances in Preventing Lead Poisoning: A Canadian Drinking Water Case Study. Jerry Speigel(1). (1)Manitoba Department of Environment, Department of Community Health Sciences, University of Manitoba, Canada. The objective was to determine

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX B

171

how the nonhealth benefits identified in a comprehensive benefit-cost analysis can influence decisionmaking interventions to prevent lead poisoning and to help realize health benefits that may otherwise not be pursued. A case study investigation with different decisionmaking protocols for reducing health risks in drinking water was applied in Winnipeg, Canada. Different decisionmaking protocols were applied to consider risk management options, including the effect of applying a comprehensive benefit-cost analysis considering nonhealth benefits. The benefit-cost ratio identified when nonhealth benefits were considered sufficient to prompt municipal decisionmakers to pursue preventive actions in reducing lead exposure. Without consideration of these nonhealth factors, uncertainties associated with the estimation of health benefits and their valuation had prompted officials to resist intervention. In assessing policy options, it is always critical to apply a comprehensive benefit-cost approach. In this way, decisionmakers can take into account both health and nonhealth benefits. Given the uncertainties associated with the valuation of the health benefits of lead poisoning prevention, consideration of nonhealth benefits can help to overcome resistance to pursuing preventive measures. Worker Training on Lead: The AFSCME Experience. Carlos Eduardo Siquiera(1). (1)American Federation of State, County and Municipal Employees Washington, D.C., U.S.A. Effective worker training has been shown, and is widely believed, to be an important tool in reducing lead exposures in the workplace. This poster discusses some of the critical issues faced by the American Federation of State, County and Municipal Employees' Health and Safety Training Program over the last 12 years. We looked at political and financial issues, legislative challenges, and, over the last three years, some highly effective joint labor-management training efforts across the United States, and the applicability of the experience to Latin America.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX B 172

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX C

173

APPENDIX C ANALYTICAL METHODS FOR BLOOD LEAD MEASUREMENT ROBERT L. JONES*

Lead is one of the most ubiquitous environmental contaminants in the modern world. It is therefore very important that the laboratory and the people collecting the blood lead samples be very aware of the extreme potential for contamination. One of the most important aspects of the laboratory is that the laboratorians must communicate with the people collecting the samples and make them aware of the high potential for contamination. In Expanded Program on Immunization (EPI) studies, if the samples are collected incorrectly, the entire study could be compromised. In controlled studies it is imperative that the laboratory prescreen the blood sample containers AND the collection devices such as the butterflies, syringes, needles, and the like for lead contamination. If the laboratory cannot prescreen the blood collection devices, then the persons collecting the blood should use “lead-free” collection devices. Two kinds of whole blood specimens are usually presented to the laboratory—microsamples (capillary or “microtainer,” less than 0.5 ml) and macrosamples (“Vacutainer,” 2 ml or greater). In either case, one key consideration is lot testing of the collection containers themselves, as well as any other devices that directly contact the specimen (for example, needles, cotton gauze swabs, “butterfly” blood collectors, and the like). A copy of the U.S. Centers for Disease Control and Prevention (CDC) procedures for lot testing is available for additional information on lot testing. Microsamples are more likely to clot, and any collected in glass capillaries (not recommended for safety considerations) are inherently more difficult to sample. In all cases it is recommended that whole blood be preserved with EDTA (heparin will work but is more prone to microclots), and shipped and stored at 4°C. The use of filter paper blood collection is not recommended at this time because of the very high potential for environ

* Centers for Disease Control and Prevention (CDC), Atlanta, Georgia.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX C

174

mental contamination and the resulting unacceptable rate of false positives. When the blood is collected, from either a fingerstick or venous, the hands or the arm of the child or adult must be properly washed, and the person collecting the specimen should be wearing powder-free gloves. There are two main analytical procedures for analyzing the blood, Anodic Stripping Voltammetry (ASV) or Graphite Furnace Atomic Absorption Spectroscopy (GFAAS). GFAAS has been vastly improved by the development of new instruments with microprocessor control; user-friendly, windowed software; capability for automated operation; improved background correction; and improved tube heating. Instruments that use ASV have also been improved, such as the ESA model 3010B, which is easier to use and is more precise and accurate, with lower detection limits than its predecessor. Several key factors should be examined in selecting the appropriate analytical method for your application. These include (but are not limited to): budget, personnel (availability, background, and experience), existing computer climate, throughput (the number of specimens to be processed and reported per unit of time), the need to analyze for elements other than lead, specimen volume available, specimen matrix, and available bench space. Other issues that influence the decision on the analytical method or the instrument manufacturer is the availability of parts and service personnel. Budget considerations are that ASV instruments cost on the order of US$15,000 per unit, and you MUST purchase the reagents from the instrument manufacturer. GFAAS instruments cost US$30,000–60,000 per instrument. Therefore, ASV has a lower initial cost, but has higher reagent costs; GFAAS has a higher initial cost, but lower reagent and gas costs. ASV is manual operation only, whereas GFAAS is normally automated. Another consideration in determining the method to use is whether there will be totally centralized testing or distributed testing. the ASV instrument is capable of being set up at various sites, whereas the GFAAS instrument is not capable of being moved to multiple locations. The need for a steady supply of Ar gas for the GFAAS is also a consideration. A supply of “lead-free” reagents and supplies (water, sample cups, pipets, standards, acids, and the like) must be obtained. A critical component of any blood lead laboratory is the quality assurance (QA) and quality control (QC). Various well-established reference laboratories recommend that the instrument standards be NIST (National Institute of Standards and Technology) traceable. The instrument should be calibrated using multiple standards that cover the appropriate analytical

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX C

175

range. Multiple QC materials should be used (commercially available or NIST traceable) to check each analytical ran. A minimum of two QC materials should be used, a “normal” and an “elevated” value. Numerous blood lead laboratories suggest a “low,” “normal, and “high” QC material at the beginning and at the end of the analytical ran, as well as some periodically throughout the run. Many laboratories will evaluate quality with an internal system (bench and blind QC materials as above), as well as participate in an “external” QA/QC system. Examples of these external systems are the CDC/WI Proficiency Testing (PT) Program, the New York State PT program, The College of American Pathologists PT program, or the CDC lab standardization program (Blood Lead Laboratory Reference System BLLRS). Accuracy in determination of lead in these external programs is often the basis of laboratory certification. Reporting requirements should be considered. Most of the GFAAS instruments are microcomputer-controlled and would allow for electronic uploading and reporting of data.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX C 176

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX D

177

APPENDIX D TECHNICAL ASSISTANCE AND INFORMATION RESOURCES

ALLIANCE TO END CHILDHOOD LEAD POISONING WASHINGTON, D.C., U.S.A. The overarching question that we face is how to use all resources to translate the conference workshop recommendations and discussions, public opinion and concern, research and reports, and setbacks and successes to date into effective and sustained action to prevent and eliminate lead poisoning. That is precisely the Alliance to End Childhood Lead Poisoning's mission. The Alliance believes that the worldwide elimination of lead poisoning would constitute a major achievement, and it would also serve as an optimism-engendering model of international cooperation to further the Post-Rio (UNCED) agenda of sustainable development and environmental protection. The Alliance has produced a framework for action in a set of documents: the Primary Prevention Strategies Handbook (three volumes designed to convince decisionmakers to support prevention efforts, to delineate the steps involved in developing prevention programs, and to collect materials currently used in prevention programs); The Global Dimensions of Lead Poisoning: An Initial Analysis (report on the nature of lead poisoning worldwide); the Final Report of the Global Dimensions of Lead Poisoning: The First International Prevention Conference (report reflecting the work of participants from 37 countries who worked together to build the basis of coordinated solutions to lead poisoning internationally); and the International Action Plan for Preventing Lead Poisoning (framework outlining the coordinated action steps at all levels –international, regional, national, and community– needed to achieve prevention). The Alliance is committed to a worldwide advocacy campaign to accelerate and complete leaded gasoline phaseout as its international priority. The Alliance is also in the process of developing an international lead advocacy network. For further information, please call or write to:

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX D

178

Alliance to End Childhood Lead Poisoning 227 Massachusetts Ave., N.E., Suite 200 Washington, D.C. 20002, U.S.A. Telephone: (202) 543-1147 Fax: (202) 543-4466 Internet: [email protected] CENTERS FOR DISEASE CONTROL AND PREVENTION (CDC) ATLANTA, GEORGIA, U.S.A. The Centers for Disease Control and Prevention (CDC) is an agency of the United States (U.S.) federal government. As the nation's prevention agency, its mission is to promote health and the quality of life by preventing and controlling disease, injury, and disability. Its vision is Healthy People in a Healthy World – Through Prevention. Both the mission and vision are accomplished by working with its partners throughout the United States and world to: monitor health, detect and investigate health problems, conduct research to enhance prevention, develop and advocate sound public health policies, implement prevention strategies, promote healthy behaviors, foster safe and healthy environments, and provide leadership and training. CDC's partners include U.S. state and local health departments, international agencies and organizations, academic institutions, and others. Within the CDC's public health structure, there are specialized centers, institutes, and offices. The National Center for Environmental Health (NCEH), for example, works with U.S. federal, state, and local health and environmental departments and regulatory agencies, and with international organizations such as the Pan American Health Organization, to reduce the adverse effects of environmental hazards, particularly those that affect children and the underserved. A high priority of NCEH is the prevention of childhood lead poisoning. Using the tools of prevention –surveillance, health statistics, epidemiology, health communication, laboratory services, and new program technologies– NCEH's Lead Poisoning Prevention Branch works in close collaboration with its many national and international partners in an effort to eliminate childhood lead poisoning as a major public health problem. Grants and technical assistance also are provided to state and local health agencies for the development and implementation of effective childhood lead poisoning prevention programs. NCEH is especially committed to working with the international public health commu

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX D

179

nity. Based on available resources, NCEH provides consultation and works collaboratively on: • • • • • •

development of prevention activities and strategies; surveillance and epidemiology; training, outreach, and education strategies; program development and program management; laboratory procedures and methodologies; studies on the effectiveness of interventions.

For further information, please call or write to: Lead Poisoning Prevention Branch (F-42) Division of Environmental Hazards and Health Effects National Center for Environmental Health 4770 Buford Highway, N.E. Atlanta, GA 30341-3724, U.S.A. Telephone: (404) 488-7330 Fax: (404) 488-7335 ENVIRONMENTAL DEFENSE FUND (EDF) WASHINGTON, D.C., U.S.A. The Environmental Defense Fund (EDF) is a not-for-profit nongovernmental advocacy organization with nearly 300,000 members in the United States. EDF's scientists, economists, and lawyers work to create innovative, economically viable solutions to today's environmental problems. EDF's activities include publishing reports, developing public education campaigns, participating before U.S. and international standard-setting and regulating bodies, and providing technical and policy information to decisionmakers in the public and private spheres. In addition to its 1993 report The Global Dimensions of Lead Poisoning (coauthored with the Alliance to End Childhood Lead Poisoning), EDF has published Legacy of Lead: America's Continuing Epidemic of Childhood Lead Poisoning (1990); The Hour of Lead: A Brief History of Lead Poisoning in the United States (1992), and At A Crossroads: State and Local Lead-Poisoning Programs in Transition (1992). EDF is familiar with a number of sources of technical information on lead production, use, and toxicity.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX D

180

For further information, please call or write to: Karen Florini Senior Attorney 1875 Connecticut Avenue, N.W. Washington, D.C. 20009, U.S.A. Telephone: (202) 387-3500 Fax: (202) 234-6049 Internet: [email protected]. U.S. ENVIRONMENTAL PROTECTION AGENCY (EPA) WASHINGTON, D.C., U.S.A. The U.S. Environmental Protection Agency (EPA) is responsible for implementing a wide range of environmental statutes that control pollution sources affecting the air, water, and solid wastes. The agency also implements cross-media statutes related to the control of industrial chemicals and the promotion of pollution prevention. A number of statutes give the EPA responsibility for managing and controlling lead exposures and hazards. The Clean Air Act resulted in the virtual phasing out of lead in gasoline. Currently the EPA is placing increased emphasis on reducing exposure to lead through drinking water systems and controlling lead paint hazards in the home. With progress in these areas, we expect to see continuing declines of blood lead levels in children – especially for those children who are poor, minority, and live in large inner cities. For further information, please call or write to: Joe Carra, Deputy Director Office of Pollution Prevention and Toxics Environmental Protection Agency 401 M Street, S.W. (7401) Washington, D.C. 20460, U.S.A. Telephone: (202) 260-1815 Fax: (202) 260-0575

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX D

181

FOGARTY INTERNATIONAL CENTER (FIC), NATIONAL INSTITUTES OF HEALTH (NIH) BETHESDA, MARYLAND, U.S.A. International Biomedical and Behavioral Research Opportunities for U.S.-Latin American and Caribbean Collaboration in Lead Research

International Research Fellowships: For foreign postdoctoral and behavioral scientists, with up to two years of advanced research training and collaborative research with a host scientist at a U.S. university (6 annually), nominations by “home” country. Senior International Fellowship Program: For established U.S. scientists to conduct collaborative research abroad, on invitation from foreign institution, for 3 to 12 months (may be divided over 3-year period). Fogarty International Research Collaboration Award (FIRCA): U.S. NIH grantees may compete for small grants to collaborate with colleagues in Latin American and Caribbean countries. NIH Visiting Program: FIC administers a program to place qualified foreign scientists in NIH intramural laboratories, on a case-bycase basis; invitation from NIH Laboratory, salary provided; guest researchers, salary not provided. For further information, please call or write to: Dr. Arlene Fonaroff Program Officer for the Americas, WHO and PAHO Fogarty International Center, NIH 31 Center Drive, MSC 2220 Bethesda, MD 20892-2220, U.S.A. Telephone: (301) 496-4784 Fax: (301) 480-3414

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX D

182

THE U.S. FOOD AND DRUG ADMINISTRATION (FDA) WASHINGTON, D.C., U.S.A. The U.S. Food and Drug Administration (FDA) is focusing on lead exposure related to the following products under its jurisdiction: food, lead-soldered cans, calcium dietary supplements, food additives, bottled water, wines, wine bottle seals, packaging, ceramicware, and other foodware (such as silver-plated hollowware). The effort is directed toward determining the relative contribution of each source to overall exposure and taking steps that are reasonable and statutorily justified to reduce or eliminate lead exposure from these sources. This FDA program of dietary lead source identification and abatement is relevant to the Institute of Medicine's considerations of remediation efforts for lead in the Americas. For further information, please call or write to: Source identification and health effects: Michael Bolger, Ph.D., D.A.B.T. Chief, Contaminants Branch HFS-308, FDA, 200 C Street, S.W. Washington, D.C., 20204, U.S.A. Telephone: (202) 205-8705 Fax: (202) 260-0498 Internet: [email protected] Regulatory efforts: Michael Kashtock, Ph.D. Chief, Regulations and Enforcement Branch HFS-306, FDA, 200 C Street, S.W. Washington, D.C., 20204, U.S.A. Telephone: (202) 205-4681 Fax: (202) 205-4422 FUNDACION NATURA QUITO, ECUADOR Fundacion Natura is a not-for-profit, nongovernmental organization specializing in the protection of biodiversity and environmental health through programs of investigation, development projects, and policy formulation. In 1991 research was carried out on the levels of lead in the environment in Quito. Blood samples of 160 people were analyzed that showed levels of

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX D

183

lead considerably above internationally accepted norms. Newborn children displayed levels of 14 µg/dl, while those of seven-year-olds reached 28 µg/dl. With these results, Fundacion Natura started a campaign to reduce the level of lead additives in gasoline; since then the consumption of unleaded fuel has risen by 20 percent, and one city plans to eliminate lead completely from its gasoline at the beginning of 1996. Fundacion Natura published three factsheets that focus on lead poisoning including: Lead Pollution (Contaminacion por Plomo); Risks Associated with Environmental Lead in Quito (Valoracion del Riesgo del Plomo Ambiental en Quito); and Lead –A Spoonful for Breakfast and another for Lunch (Plomo: una cucharadita en el desayuno y otra en el almuerzo). The last of these refers to the fact that children are most exposed to environmental lead produced by traffic exhaust fumes during these periods. For further information, please call or write to: Mr. Jorge Oviedo Casilla 17-01-253 Quito, Ecuador Telephone: (593) 2-447-341/2/3/4 Fax: (593) 2-447-449 Internet: [email protected] APC: [email protected] HEALTH RESOURCES AND SERVICE ADMINISTRATION (HRSA) U.S. DEPARTMENT OF HEALTH AND HUMAN RESOURCES WASHINGTON, D.C., U.S.A. Through our director, Dr. Ciro Sumaya, the Health Resources and Service Administration (HRSA) of the United States Public Health Service (USPHS) extends a hand to assist countries and locales in the Americas with the problem of hazardous lead exposure. HRSA staff provide consultation and assistance on request. Highlights of HRSA's program related to lead poisoning include the following. The Maternal Child Health Bureau (MCHB) has, over the last two and a half decades, provided leadership in identifying lead poisoning as a critical problem in children, advocating for lead screening and intervention as part of routine pediatric health supervision. In the early 1970s, the MCHB, under the leadership of Dr. Jane Lin-Fu, called attention to the possible damage caused by lead in children without overt symptoms of lead poisoning. Her work stimulated research into lead toxicity at relatively “low” levels. This

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX D

184

lead to progressive lowering of blood lead levels considered toxic in children. Dr. Lin-Fu is a recognized expert in the field and is available for consultation. HRSA's Bureau of Primary Health Care and Maternal Child Health Bureau promote public education, as well as lead screening and care through our extensive network of public and private primary care for the underserved: community and migrant health centers, health department clinics, health centers in public housing, and school and preschool programs. HRSA has also developed an alliance of primary care providers, parents, public health authorities, and other community activists. When elevated blood lead results become common in a community, parents can be brought together for education about sources of hazardous lead exposure, lead's modes of entry into children's bodies, and toxic effects of lead. Parents become active participants in developing strategies to minimize lead exposure through hygienic measures in the home. Together they can become a force with others in the community working on issues of environmental justice. For further information, please call or write to: Dr. Jane S. Lin-Fu Maternal Child Health Bureau, HRSA 5600 Rockville Lane, Rm. 18-A20 Rockville, MD 20857, U.S.A. Telephone: (301) 443-1080 Fax: (301) 443-1728 Dr. Patricia Salomon Bureau of Primary Health Care, HRSA 4350 East-West Highway Bethesda, MD 20814, U.S.A. Telephone: (301) 594-4119 Fax: (301) 594-4072 INTERNATIONAL DEVELOPMENT RESEARCH CENTRE (IDRC) OTTAWA, ONTARIO, CANADA The International Development Research Centre (IDRC) is a public corporation created by the Parliament of Canada in 1970 to support research designed to adapt science and technology to the needs of developing

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX D

185

countries. The Centre's activity is concentrated in five sectors: agriculture; food and nutrition sciences; health sciences; information sciences; and social sciences. IDRC is funded solely by the Parliament of Canada; its policies, however, are set by an international Board of Governors. The Centre's headquarters are in Ottawa, Canada. Regional offices are located in Africa, Asia, Latin America, and the Middle East. The IDRC, through its Health Sciences Division, supports the Lead in the Americas initiative and is interested in the environmental and occupational health impacts of free trade involving developing countries, which may involve increases and/or changes in the production and use of lead. In the past, IDRC has supported and encouraged research in a six-country South American study of heavy metals, including lead, in river water pollution; in a Chilean study of lead levels in newborns; in wastewater heavy metal pollution from Mexico City used in irrigation; in the community health effects of lead smelters in San Luis Potosi in Mexico; and in advising Jamaican researchers concerning backyard lead battery reclamation and its community health effects. We look forward to continuing this work in the future in cooperation with the welcome initiative of the Institute of Medicine, because international cooperation among researchers and funders is likely to optimize the research results for money spent and to help disseminate the results to protect community and worker health. For further information, please call or write to: Dr. John Markham Senior Program Specialist in Occupational and Environmental Health Health Sciences Division International Development Research Centre 250 Albert Street, 12th Floor Ottawa, Ontario, Canada K1G 3H9 Telephone: (613) 236.6163 Fax: (613) 567-7748 INTERNATIONAL LEAD ZINC RESEARCH ORGANIZATION, INC. (ILZRO) RESEARCH TRIANGLE PARK, NORTH CAROLINA, U.S.A. The International Lead Zinc Research Organization, Inc. (ILZRO), is a not-for-profit research management organization that serves as the cooperative research arm of the international nonferrous metal mining, smelting, and user industries involved in the production and use of lead, zinc, and

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX D

186

cadmium. The activities of the ILZRO are supported by member companies throughout the world. The primary purpose of ILZRO is the sponsorship of research. Research funding programs are maintained in diverse areas that include environment and health, electrochemistry, metallurgy, and galvanizing. ILZRO awards Environment and Health Research Grants to investigators throughout the international scientific community. The principal purpose of ILZRO's Environment and Health research program is to contribute to our knowledge of the human health and/or environmental health effects that might be anticipated as a result of exposure to heavy metals such as lead, zinc, or cadmium. Research proposals submitted to ILZRO are generally received in response to “requests for proposals.” ILZRO periodically evaluates areas of concern to the international community and targets high-priority areas for focused research activity. ILZRO research support is available to investigators anywhere in the international scientific community. ILZRO also undertakes a variety of technology transfer activities in all areas of its research portfolio. Technology transfer activities are diverse in nature and include informal consultations, conferences, training courses, informational materials, and seminars. A number of past ILZRO activities have been conducted in Latin America and have ranged from technology transfer conferences (for example, zinc die-casting) and the support of research (such as the effects of lead exposure on child development in Mexico City). For further information, please call or write to: Dr. Craig Boreiko Manager, Environment and Health, ILZRO P.O. Box 12036 Research Triangle Park, NC 27709, U.S.A. Telephone: (919) 361-4647 Fax: (919) 361-1957 ILZRO staff are also available for consultation on a variety of technical matters and can facilitate networking between public and private sector interests. NATIONAL CENTER FOR LEAD-SAFE HOUSING COLUMBIA, MARYLAND, U.S.A. The National Center for Lead-Safe Housing is a nonprofit organization dedicated to reducing the incidence of childhood lead poisoning, while

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX D

187

preserving the nation's stock of low-income, affordable housing. It conducts research to determine the most costeffective ways to identify lead-based paint hazards in housing –for example, sampling of deteriorated paint, dust, and soil–and to control these hazards. For example, the National Center for Lead-Safe Housing prepared the new Guidelines for the Evaluation and Control of Lead-Based Paint Hazards in Housing, a 700-page technical document from the U.S. Department of Housing and Urban Development (available from HUD User at 1-800-245-2691). Other initiatives include studies of different types of hazard control, ranging from replacement of contaminated building components to simple cleaning and repainting. The Center also helps local governments design practical regulations, policies, and programs to help ensure that financial resources are used wisely and are available. The Center has provided testimony and technical assistance to cities and states and serves on a number of different task forces. For further information, please call or write to: Walter G. Farr Executive Director National Center for Lead-Safe Housing 10227 Wincopin Circle, Suite 205 Columbia, MD 21044, U.S.A. Telephone: (410) 992-0712 Fax: (410) 715-2310 Internet: [email protected] NATIONAL INSTITUTE OF ENVIRONMENTAL HEALTH SCIENCES (NIEHS), NATIONAL INSTITUTES OF HEALTH (NIH) BETHESDA, MARYLAND, U.S.A. The National Institute of Environmental Health Sciences (NIEHS) is one of the National Institutes of Health (NIH) and is committed to reducing the burden of human illness and dysfunction from exposures to environmental agents through multidisciplinary biomedical research, and prevention and intervention efforts. Exposure to lead is one of the major concerns of NIEHS and has been the target of considerable research over the past 25 years. The objective of research is to drive public policy to prevent disease. Multidisciplinary research by scientists in NIEHS laboratories and by

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX D

188

scientists in universities and other research institutes supported by grants from the NIEHS has identified the effects of low-level lead exposure, particularly effects of lead on the developing nervous system of the fetus, infants, and young children. This information has provided the scientific basis for current international prevention and intervention strategies. NIEHS publishes the journal, Environmental Health Perspectives, which is a forum for discussion of environmental issues. Supplements to the journal contain scientific reviews of topics in environmental health sciences. These may include papers from scientific meetings, conferences, and workshops. The NIH/NIEHS, through the Fogarty International Center, provides opportunities for United States-Latin American and Caribbean collaboration in biomedical and behavioral research on health effects of lead and other environmental agents. Research conducted under these grants may consist of collaborations between scientists in the Americas and scientists at the NIH, including NIEHS, or with scientists conducting research supported by the NIH at a U.S. university. Full details on the specific fellowships and grants programs can be obtained by contacting the Fogarty Center (contact information given above). For further information, please call or write to: Dr. Terri Damstra Assoc. Director for International Programs and Program Coordinator Division of Intramural Research, NIEHS PO Box 12233, Mail Stop A2-07 Research Triangle Park, NC 27709, U.S.A. Telephone: (919) 541-3467 Fax: (919) 541-4075 NATURAL RESOURCES DEFENSE COUNCIL (NRDC) WASHINGTON, D.C., U.S.A. The Natural Resources Defense Council (NRDC) is a national nonprofit environmental organization, founded in 1970, dedicated to protecting the world's natural resources and ensuring a safe and healthy environment for all people. Since 1973, when we brought a lawsuit against the U.S. government to enforce the phaseout of leaded gasoline and enable the installation of catalytic converters on automobiles, NRDC has worked to reduce lead exposure in the United States and abroad. More recently, we have focused on removing lead from drinking water and well pumps. At

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX D

189

the international level, NRDC is promoting the phaseout of leaded gasoline as a concrete step on the road to sustainable development. We are working with the United Nations Commission on Sustainable Development and the Summit of the Americas to encourage countries to phase out leaded gasoline. NRDC has also initiated a project with Russian policymakers and scientists to create public support for lead phaseout in Russia. For further information, please call or write to: Jacob Scherr Director International Program Natural Resources Defense Council 1350 New York Avenue, N.W., Ste. 300 Washington, D.C. 20005, U.S.A. Telephone: (202) 783-7800 Fax: (202) 783-5917 Internet: [email protected] CENTER FOR HUMAN ECOLOGY AND HEALTH (ECO), PAN AMERICAN HEALTH ORGANIZATION (PAHO) METEPEC, MEXICO The Center for Human Ecology and Health (ECO) of the Pan American Health Organization (PAHO) is located in Metepec, outside of Mexico City. The Center provides technical assistance to the ministries of health of Latin America and the Caribbean through the PAHO missions located in almost every country in the Americas. These missions are the principal asset of the organization, and they can be a valuable channel for multinational communication, for technical assistance to the countries, and for compiling information regarding activities and studies in the various countries of the region regarding lead. ECO has recently completed a preliminary survey of the use of lead in the countries in the region, using information collected and provided by the environmental health advisers in each of the PAHO missions. These data were presented at the conference. ECO recently produced, with the Institute of Public Health and the Federal District of Mexico, a manual on procedures for blood sampling for lead (in Spanish). The Center also recently translated into Spanish for distribution in the Americas the recommendations of the American Academy of Pediatrics regarding lead exposure in children. Other activities of the Center that involve lead, or could be adapted to facilitate multilateral

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX D

190

collaboration for evaluating and controlling the hazards of lead in the Americas, include: • A network of quality-controlled laboratories for the evaluation of metals, currently being developed by ECO with support from the German government; • A small grants program for the development of pilot research projects based on inter-American cooperation, involving U.S. and Latin American or Caribbean investigators (with support from the United States Environmental Protection Agency (EPA); • A risk assessment course conducted jointly by ECO and EPA scientists, and direct to the development of pilot projects in risk assessment in countries of Latin America and the Caribbean; • A scholarship program for Latin American public health professionals to obtain a masters in environmental health at the National Institute of Public Health in Mexico and to develop a thesis in the home country (in collaboration between the Institute of Public Health, the U.S. Centers for Disease Control and Prevention (CDC), and PAHO/ECO). This program may soon be expanded to include faculty exchanges; • A tutorial fellowship in environmental and occupational epidemiology for epidemiologists from the ministries of health in Latin America and the Caribbean (in collaboration with ECO, the Mexican General Directorates of Epidemiology and Environmental Health, and the CDC). For more information regarding these activities, please contact: Dr. Rob McConnell Director, ECO/OPS Apartado Postal 37-473 06696 Mexico, D.F., MEXICO. Internet: ECO_DIR_at_ECO/[email protected]

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX E

191

APPENDIX E CONFERENCE AGENDA

Lead in the Americas: Strategies for Disease Prevention National Institute of Public Health–Institute of Medicine Av. Universidad No. 655, Col. Sta. María Ahuacatitlán C.P. 62508 Cuernavaca, Morelos México 8–10 May 1995 Monday, 8 May Plenary session 8:00 a.m.

Registration, National Institute of Public Health Auditorium Lobby

9:00 a.m.

Welcome and Introduction • ... Juan Ramon de la Fuente, M.D. (to be confirmed) Secretary of Health, Mexico • ... Hugo Aréchiga, M.D. President, National Academy of Medicine, Mexico • ... Kenneth Shine, M.D. President, Institute of Medicine, USA • ... Jaime Sepúlveda, M.D., Dr.Sc. Director, National Institute of Public Health, Mexico

9:40 a.m.

Keynote Address • ... Jorma Rantanen, M.D. Director General Finnish Institute of Occupational Health Finland

10:15 a.m.

Break

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX E

192

Session I.

Health Effects Of Lead Moderator: Howard Frumkin, M.D. Chair, Department of Occupational and Environmental Health Rollins School of Public Health, USA

10:45 a.m.

Effect of Lead on Children's Health • ... Eduardo Palazuelos-Rendón, M.D. Federal District Department Minister of the Environment, Mexico City, Mexico

11:10 a.m.

Questions and Answers

11:15 a.m.

Effects of Lead on Adult Health • ... Julieta Rodríguez de Villamil, M.D. Assistant Secretary of Occupational Health Ministry of Health, Colombia

11:40 a.m.

Questions and Answers

11:45 a.m.

Discussion

12:15 p.m.

Break • ... Poster Session Presentations (See Attachment A)

Session II.

Case Studies Of Interventions Moderator: David Rall, M.D., Ph.D. Committee Chairman Committee to Reduce Lead Exposure in the Americas, IOM

12:45 p.m.

Introduction • ... David Rall, M.D., Ph.D.

1:00 p.m.

Voluntary Industry Initiative: Removal of Lead Solder from Cans • ... Alfonso de León Director General National Chamber for Metalic Containers, Mexico

1:25 p.m.

Questions and Answers

1:30 p.m.

Government Regulation: U.S. Gasoline Lead Reduction • ... Robert Scala, Ph.D. (presented by Len Ritter, Ph.D.) Retired Scientist Exxon Biomedical Sciences, Inc., USA

1:55 p.m.

Questions and Answers

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX E

193

2:00 p.m.

Discussion

2:30 p.m.

Plenary Session Adjourned

2:30 p.m.

Lunch • ... Poster Session Presentations (continued)

4:00–7:00 p.m.

Working group sessions (See Attachment B)

7:00 p.m.

Monday adjournment

Tuesday, 9 May Workshop 8:00–9:30 a.m.

Analytical Methods for Blood Lead Measurements-Part I • ... Robert Jones, Ph.D. Research Chemist U.S. Centers for Disease Control and Prevention

Plenary session Session III.

Extent, Sources, and Pathways of Lead Exposure in the Hemisphere Moderator: Carlos Santos Burgoa, M.D., M.P.H., Ph.D. Professor, Senior Professor-Researcher National Institute of Public Health, Mexico

9:30 a.m.

Historical Perspectives • ... Jerome Nriagu, Ph.D. Professor National Water Research Institute, University of Michigan, USA

9:55 a.m.

Questions and Answers

10:00 a.m.

Prevalence of Exposure and Data Quality • ... Isabelle Romieu, M.D. Pan American Center for Human Ecology and Health, Mexico

10:25 a.m.

Questions and Answers

10:30 a.m.

Major Sources and Pathways of Lead Exposure • ... Ellen Silbergeld, Ph.D. University of Maryland, USA

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX E

194

10:55 a.m.

Questions and Answers

11:00 a.m.

Discussion

11:30 a.m.

30-Minute Break • ... Poster Session Presentations (See Attachment A)

Session IV.

Case Studies of Interventions Moderator: Len Ritter, Ph.D. Director University of Guelph-Center for Toxicology, Canada

12:00 p.m.

International Organized Labor • ... John Repko, Ph.D. Director of Health Effects Carpenters Health and Safety Fund, USA

12:25 p.m.

Questions and Answers

12:30 p.m.

Community Activism and Education • ... Cristina Von Glascoe, M.D., Ph.D. Researcher North Border College, Mexico

12:55 p.m.

Question and Answers

1:00 p.m.

Discussion

1:30 p.m.

Plenary Session Adjourned

1:30 p.m.

Lunch • ... Poster Session Presentations (continued)

3:00–6:00 p.m

Working group session (See Attachment B)

6:00 p.m.

Tuesday adjournment

Wednesday, 10 May

Workshop 8:00–9:30 a.m.

Analytical Methods for Blood Lead Measurements – Part II • ... Robert Jones, Ph.D. Research Chemist U.S. Centers for Disease Control and Prevention

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX E

195

Plenary session Session V. 9:30 a.m.

Closing plenary • ... Moderator: David Rall, M.D., Ph.D. • ... Rapporteur Reports from the Working Group Sessions: • • • • • •

... Ellen Silbergeld, Ph.D. ... David Jacobs, C.I.H. ... Mauricio Hernández-Avila, M.D., Dr.Sc. ... Robert Scala, Ph.D. ... Tania Tavares, Ph.D. ... Howard Frumkin, M.D.

10:30 a.m.

30-Minute Break

11:00 a.m.

Plenary Discussion • ... Identification of common strategies and action steps for reducing lead exposures • ... Responsible parties: Ensuring that action steps for lead exposure reduction are met

12:30 p.m.

Summary and Identification of Action Plans • ... Howard Frumkin, M.D.

1:00 p.m.

Technical Assistance and Support • • • • • • • • •

2:00 p.m.

... Alliance to End Childhood Lead Poisoning ... U.S. Centers for Disease Control and Prevention ... Environmental Defense Fund ... U.S. Environmental Protection Agency ... International Lead Management Center/International Lead Zinc Research Organization, Inc. ... International Development Research Centre ... U.S. National Institute of Environmental Health Sciences/National Institutes of Health ... Organization for Economic Cooperation and Development ... Pan American Health Organization/World Health Organization

Closing Remarks • ... Christopher Howson, Ph.D., Institute of Medicine, USA • ... Mauricio Hernández-Avila, M.D., Dr.Sc., National Institute of Public Health, Mexico

2:15 p.m.

Meeting Adjournment

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX E

196

ATTACHMENT A Poster Sessions Alameda County Lead Poisoning Prevention Program (USA) ... Rebecca Carrillo and Dario Hunter Community Health Outreach Workers Oakland, CA, USA Alliance to End Childhood Lead Poisoning: International Action Plan for Preventing Lead Poisoning (USA) ... Maria Rapuano and K. W. James Rochow Alliance to End Childhood Lead Poisoning Washington, DC, USA Blood Lead Levels According to Branch of Industrial Activity: September 1992-September 1994 (Dominican Republic) ... Dra. Carmen Yris Delgado Pantaleón Pan American Health Organization Dominican Republic Blood Lead Levels in Trinidad, West Indies (West Indies) ... Ivan Chang-Yen, Ph.D. Senior Lecturer, Analytical Chemistry Trinidad, West Indies Childhood Lead Poisoning Prevention: Yesterday, Today, and Tomorrow in the Far West (USA) ... L. Rex Ehling, M.D., M.P.H. Childhood Lead Poisoning Prevention Branch California Department of Health Services, U.S.A. Community Action and Reduction of Lead Exposure: The Trail, B.C. Experience (Canada) ... Terry Oke Administrator Trail Lead Program Trail, B.C., Canada

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX E

197

Cottage Industries and the Reduction of Lead Exposure: Battery Breaking (Jamaica) ... Peter Figueroa, M.B.B.S., D.P.H. Principal Medical Officer Epidemiology Jamaican Ministry of Health, Jamaica Cottage Industries and the Reduction of Lead Exposure: Ceramicware (Mexico) ... Mario Covarrubias Mexico Development of A Statewide Database on Lead-Safe Housing and Identifying Communities with High Risk of Lead Poisoning (USA) ... Joan Luckhardt, Ph.D., and Robert Haug Director, Lead Poisoning Prevention Program, University of Medicine and Dentistry of New JerseySOM Stratford, NJ, USA Educational Interventions to Change Head Start Parents' Behavior to Prevent Lead Poisoning Among Young Children (USA) ... Cecile Dickey, M.A. St. Peters College Jersey City, NJ, USA Effect of A Nutritional Intervention in Order to Reduce Lead Exposure in Infants (Mexico) ... Antrop. Sandra Treviño and Lic. Eugenia Fishbein National Institute of Public Health Cuernavaca, Mexico Epidemiological Analysis of Lead Exposure in Four Different Sources of Occupational Exposure (Colombia) ... Nancy Patiño Reyes, M.D. District Secretary of Health Bogotá, Colombia Families Exposed to Lead: A Public Health Problem (Colombia) ... Nancy Patiño Reyes, M.D. District Secretary of Health Bogotá, Colombia

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX E

198

Fouling the Nest/Industrial and Occupational Contamination Brought Home (Brazil) ... Fernando Martin Carvalho Professor Universidade de Federal da Bahia, Brazil Lead Content in Tropical Vegetables and Fruits Grown Around a Smelter, Bahia (Brazil) ... Tania Tavares, Ph.D. Instituto de Quimica Universidade Federal da Bahia, Brazil National Lead Information Center (USA) ... Janet Phoenix, M.D., M.P.H. Manager, Public Health Programs National Lead Information Center Occupational Blood Lead Trends in Manitoba, 1979–1994: Assessing the Effectiveness of Regulation and Surveillance (Canada) ... Annalee Yassi, M.D. Director, Occupational and Environmental Health Unit & Associate Professor University of Manitoba, Canada Occupational Exposure to Lead According to Altitude (Bolivia) ... René Córdova Cardozo, M.D. Chief of Labor Medicine, Bolivia Protection Against Lead During Pregnancy Through the Consumption of Milk and Orange Juice: The Case of Mexico City (Mexico) ... Luz. Helena Sanín A. National Institute of Public Health Cuernavaca, Mexico Reducing Sources of Lead Through Community Education (USA) ... Joan Cook Luckhardt, Ph.D., and Stacey Kenyon, M.A. Director, Lead Poisoning Prevention Program, University of Medicine and Dentistry of New Jersey– SOM Stratford, NJ, USA

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX E

199

Regulation and Reduction of Lead Exposure: California and Proposition 65 (USA) ... David Roe, Ph.D. Environmental Defense Fund Oakland, CA, USA Regulation and the Reduction of Lead Exposure: Gasoline (USA) ... Judy MacGregor, Ph.D. Private Consultant, Toxicology Consulting Services Danville, CA, USA Relationship Between Blood Lead Levels in Children and Lead Mining Activities ... Ana Maria Murgueytio, M.D., M.P.H. St. Louis University School of Public Health St. Louis, MO, USA Risk Factors Associated with High Lead Blood Levels in Mexico City Schoolchildren (Mexico) ... Dra. Rosalba Rojas Martínez Director, Effects of Air Pollution on Health Mexico City, Mexico Substitution of Leadless Ceramic Glazes (USA) ... Michael McCann, Ph.D., C.I.H. President Center for Safety in the Arts, USA Using Benefit-Cost Analysis to Build Alliances in Preventing Lead Poisoning: A Canadian Drinking Water Case Study (Canada) ... Jerry Spiegel, M.S. Director, Pollution Prevention Manitoba Environment, Canada Voluntary Industry Initiative: Alco-Pacifico (US–Mexico) ... Ing. Francisco Bahamonde Director General de Delegaciones Federales del Trabajo Mexico

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX E

200

Worker Training on Lead: The American Federation of State, County and Municipal Employees Experience (USA) ... Carlos Eduardo Siqueira, M.D., M.P.H. Hazardous Waste Specialist American Federation of State, County and Municipal Employees, USA ATTACHMENT B Working Group Sessions Working Group I: Gasoline ... Moderator Jacobo Finkelman, Ph.D. Pan American Health Organization, Guatemala ... Rapporteur Ellen Silbergeld, Ph.D. University of Maryland, USA Working Group II: Paint ... Moderator Kate Mahaffey, Ph.D. U.S. Environmental Protection Agency, USA ... Rapporteur David Jacobs, C.I.H. National Center for Lead Safe Housing, USA Working Group III: Ceramicware Glazes ... Moderator Gustavo Olaíz Fernández, M.D. Salud Ambiental, SSA, Mexico ... Rapporteur Mauricio Hernández-Avila, M.D., Sc.D. National Institute of Public Health, Mexico

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX E

Working Group IV: Industrial and Occupational Health ... Moderator Robert McConnell, M.D. Pan American Health Organization, Mexico ... Rapporteur Robert Scala, Ph.D. Exxon Biomedical Sciences, Inc., USA Working Group V: Food, Water, and Waste Disposal ... Moderator Len Ritter, Ph.D. Canadian Network of Toxicology Centres, Canada ... Rapporteur Tania Tavares, Ph.D. Universidade Federal da Bahia, Brazil Working Group VI: Techniques for Improved Surveillance and Monitoring of Lead Exposure ... Moderator Henry Falk, M.D. Centers for Disease Control and Prevention, USA ... Rapporteur Howard Frumkin, M.D. Rollins School of Public Health of the Emory School, USA

201

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX E

202

The Institute of Medicine and the National Institute of Public Health wish to thank the following organizations for their support of the conference, Lead in the Americas: Strategies for Disease Prevention. AETNA U.S. Centers for Disease Control and Prevention Environmental Defense Fund U.S. Environmental Protection Agency International Lead Zinc Research Organization, Inc. Johnson & Johnson Family of Companies, Inc. W. K. Kellogg Foundation Endowment Fund Charles Stewart Mott Foundation U.S. National Institute of Environmental Health Sciences U.S. National Research Council World Bank

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX F

203

APPENDIX F CONFERENCE PARTICIPANTS

Lead in the Americas: Strategies for Disease Prevention National Institute of Public Health Cuernavaca, Mexico May 8–10, 1995 Adriana Alarcó Salgado Office of Environmental Protection Cuauhtemoc 1019 Chapultepec Cuernavaca, Morelos, Mexico Jerry Allsup U.S. Department of Energy Transportation Technologies 1617 Cole Blvd. Golden, Colorado 80401-3393 U.S.A. David Blanchfield U.S. Department of Energy Transportation Technologies 1617 Cole Blvd. Golden, Colorado 80401-3393 U.S.A. Victor Hugo Borja National Institute of Public Health Av. Universidad 655 Col. Sta. María Ahuacatitlán 62508 Cuernavaca, Morelos, Mexico Kim Brewer Institute of Medicine National Academy of Sciences 2101 Constitution Avenue, N.W. Washington, D.C. 20418 U.S.A.

Joseph Carra Office of Pollution Prevention Toxics U.S. Environmental Protection Agency 401 M Street SW [7401] Washington, DC 20460 U.S.A. Rebecca Carrillo Alameda County Lead Poisoning Prevention Program 2000 Embarcadero Suite #300 Oakland, California 94606 U.S.A. Fernando Carvalho Federal University of Bahia Faculty of Medicine Department of Preventive Medicine Ruo Padre Feijo 29 Canela 40110-010 Salvador-Bahia Brazil Ivan Chang-Yen Department of Chemistry The University of West Indies St. Augustine, Trinidad, West Indies

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX F

204

Enrique Cifuentes National Institute of Public Health Av. Universidad 655 Col. Sta. María Ahuacatitlán 62508 Cuernavaca, Morelos, Mexico

Henry Falk Centers for Disease Control and Prevention 4770 Buford Highway Atlanta, Georgia 30341-3724 U.S.A.

René Córdova Cardozo Ministry of Health Oficina Central La Paz Av. Saavedra 252 La Paz, Bolivia

Peter Figueroa Jamaican Ministry of Health 30-34 Halfwaytree Road Kingston 5, Jamaica

Mario Covarrubias-Pérez Ceramica Lopez, Covarrubias, Bernal Domicilio Conocido Santa María Canchesda Mpio. de Temascalcingo, Mexico Karen Danart U.S. Environmental Protection Agency U.S. Embassy-Mexico Paseo de la Reforma 305 Mexico City, Mexico Timothy Downs-Gates National Institute of Public Health Av. Universidad 655 Col. Sta. María Ahuacatitlán 62508 Cuernavaca, Morelos, Mexico L. Rex Ehling California Department of Health Services 2151 Berkeley Way Berkeley, California 94708 U.S.A Rocio Juana Maria Espinoza Lain Office of Environmental Health Las Ampolas 350 Lima 14, Peru

Jacobo Finkelman Pan American Health Organization 7a. Avenida 11-23 Zona 9, Edificio Etisa 3er.Nivel Guatemala C.A. 01009 Guatemala Eugenia Fishbein Sarafanou National Institute of Public Health Av. Universidad 655 Col. Sta. María Ahuacatitlán 62508 Cuernavaca, Morelos, Mexico Corina Flores Hernández School of Public Health of Mexico Av. Universidad 655 Col. Sta. María Ahuacatitlán 62508 Cuernavaca, Morelos, Mexico Teresa Ismelda Fortoul van der Goes Universidad Autonoma–UNAM Circuito Escolar, Copilco UNAM 04510 Mexico City, Mexico Cecile Fowler Arizona Department of Health 1400 W. Washington Street Phoenix, Arizona 85007 U.S.A.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX F

205

Howard Frumkin The Rollins School of Public Health 1599 Clifton Road Atlanta, Georgia 30329 U.S.A.

Maria Isidra Hernández-Serrato Office of the Environment San Luis Potosi 192, 5th floor Mexico City, Mexico

Silvia González Calvillo Office of Economic Development Retorno Neptuno 6 Jardines de Cuernavaca 62360 Cuernavaca, Morelos, Mexico

Craig Hooper Iowa Department of Public Health Lucas State Office Building Des Moines, Iowa 50319 U.S.A.

Robert Goyer National Institute of Environmental Health Sciences P.O. Box 12233 111 Alexander Drive Research Triangle Park, North Carolina 27709, U.S.A. Carlos Jiménez Gutierrez National Institute of Public Health Av. Universidad 655 Col. Sta. María Ahuacatitlán 62508 Cuernavaca, Morelos, Mexico Mauricio Hernández-Avila National Institute of Public Health Av. Universidad 655 Col. Sta. María Ahuacatitlán 62508 Cuernavaca, Morelos, Mexico Hortensia Hernández-Montoya National Institute of Public Health Av. Universidad 655 Col. Sta. María Ahuacatitlán 62508 Cuernavaca, Morelos, Mexico Roberto Hernández del Olmo Peñoles Industries Rio de la Plata 48 Col. Cauahtemoc Mexico City, Mexico

Christopher Howson Institute of Medicine National Academy of Sciences 2101 Constitution Avenue, N.W. Washington, D.C. 20418 U.S.A. Maurci Jackson United Parents Against Lead 1438 E. 52nd Street Chicago, Illinois 60615 U.S.A. Dave Jacobs, C.I.H. Deputy Director National Center for Lead Safe Housing 10227 Wincopin Circle, Suite 205 Columbia, Maryland 21044 U.S.A. Robert Jones Centers for Disease Control and Prevention Environmental Health Sciences 4770 Buford Highway MS F-18 Atlanta, Georgia 30341 U.S.A. John Michael Kelley Great Lakes Chemical Corporation P.O. Box 2200 West Lafayette, Indiana 47906 U.S.A. Federico Kunz-Bolaños Peñoles Industries Rio de la Plata 48 Col. Cauahtemoc, Mexico City, Mexico

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX F

Marina Lacasaña Navarro Pan American Center for Human Ecology and Health Rancho Guadalupe 06696 Metepec, Mexico Irma del Carmen Lara Sanchez Pan American Center for Human Ecology and Health Rancho Guadalupe 06696 Metepec, Mexico Robert Larbey Associated Octel Co., LTD Watling Street Milton Ketnet, United Kingdom Gary Leff 4119 N. 40th Street Arlington, Virginia 22207 U.S.A. Alfonso de León National Chamber of Canning Manufacturers Bosque de Ciruelos 190-B-301 11700 Mexico City, Mexico Lizbeth López Carrillo National Institute of Public Health Av. Universidad 655 Col. Sta. María Ahuacatitlán 62508 Cuernavaca, Morelos, Mexico Marta López University of California Cooperative Extension 328 Madera Ave. Madera, California U.S.A.

206

Lejeune Lockett-Legardy Office of Administrative Sciences National Institute of Public Health Av. Universidad No. 655 Sta. María Ahuacatitlán 62508 Cuernvaca, Morelos, Mexico Joan Luckhardt Lead Poisoning Prevention Program, University of Medicine and Dentistry of New Jersey 40 East Laurel Road Suite 200 Stratford, New Jersey 08084 U.S.A. Judith A. MacGregor Toxicology Consulting Services 383 Diablo Road, Suite 100 Danville, California 94526 U.S.A. Rob McConnell Pan American Center for Human Ecology and Health Apartado Postal 37-473 06696 Mexico City, Mexico Michael McCann Center for Safety in the Arts 5 Beekman Street, Suite 820 New York, New York 10038 U.S.A. Consuelo McDaniel New Jersey Head Start Association 244 East State Street Trenton, New Jersey U.S.A. Kate Mahaffey U.S. Environmental Protection Agency Environmental Criteria and Assessment Office 26 West Martin Luther King Drive Cincinnati, Ohio 45268 U.S.A.

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX F

207

Enrique Manzanilla U.S. Environmental Protection Agency U.S. Embassy-Mexico City P.O. Box 3087 Laredo, Texas 78044 U.S.A.

Espinosa Navarrez National Institute of Public Health Av. Universidad 655 Sta. Ma. Ahuacatitlán 62508 Cuernavaca, Morelos, Mexico

John Markham Occupational and Environmental Health Health Sciences Division International Development Research Centre 250 Albert Street, P.O. Box 8500 Ottawa, Ontario K1G 3H9 Canada

Jerome Nriagu School of Public Health University of Michigan 109 Observatory Street Ann Arbor, Michigan 48109 U.S.A.

Alfredo Méndez Vázquez Peñoles Industries Rio de la Plata 48 Col. Cuauhtemoc 06500 Mexico City, Mexico Gonzalez Fernando Meneses Office of Environmental Health Plaza de la Constitucion No. #1, 3o piso Mexico, D.F. C.P. 6067 Mexico Federico Muñoz Kurejwowki Analytical and Maintenance Service Isabel La Catolica 457 06880 Mexico City, Mexico

Octavio Ochoa Conteras Pemex Refinery Marina Nacional 329 Torre Piso 40 Huasteca 11300 Mexico City, Mexico Terry Oke Trail Lead Program Suite 300 843 Rossland Avenue Trail, BC, Canada V1R 4S8 Gustavo Olaíz Office of the Environment San Luis Potosi 192, 4th floor Col. Roma Mexico City, Mexico

Ana Maria Murgueytio St. Louis University School of Public Health 3663 Lindell Blvd. St. Louis, Missouri 63108 U.S.A.

Luis Enrique Ortega Aceves Peñoles Industries Rio de la Plata 48 Col. Cuauhtemoc 06500 Mexico City, Mexico

Patricio Murgueytio St. Louis University Dept. of Community and Family Medicine 1402 S. Grand Blvd. St. Louis, Missouri 63104 U.S.A.

Eduardo Palazuelos-Rendón Office of the Environment Plaza de la Constitucion No. #1, 3o piso Mexico, D.F. C.P. 6067 Mexico

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX F

Nancy Patiño Reyes Toxicology Chemistry Center District Secretary of Health Av. 1 de Mayo #75 A-19 Hospital Kennedy Bogota, Colombia James Peeples Polar Molecular Corporation 5894 South Sixth Street Falls Church, Virginia 22041 U.S.A. Ma. Estela Perroni-Hernández National Institute of Perintology Montes Urales 800 Mexico City, Mexico Carol Pertowski Centers for Disease Control and Prevention 4770 Buford Highway, MS F42 Atlanta, Georgia 30341 U.S.A. Rossanne Philen Centers for Disease Control and Prevention 4770 Buford Highway, F-46 Atlanta, Georgia 30341 U.S.A. David Rall Institute of Medicine 5302 Reno Road, N.W. Washington, D.C. 20015 U.S.A. Jorma Rantanen Finnish Institute of Occupational Health Työterveyslaitos 41aA SF-00250 Helsinki, Finland

208

Maria Rapuano Alliance to End Childhood Lead Poisoning 227 Massachusetts Ave, N.E., Suite 200 Washington, D.C. 20002 U.S.A. John Repko Carpenters' Health and Safety Fund 815 16th Street, N.W., Suite 301 Washington, D.C. 20006 U.S.A. Pedro Rizo Rios Pan American Center for Human Ecology and Health Rancho Guadalupe S/N Metepec, Edo. de Mexico Leonard Ritter University of Guelph-Center for Toxicology 620 Gordon Street Guelph, Ontario Canada N1G 1Y4 Jenna Roberts Environmental Defense Fund 1875 Connecticut Avenue, N.W. Washington, D.C. 20010 U.S.A. K. W. James Rochow Alliance To End Childhood Lead Poisoning 227 Massachusetts Avenue, N.E., Suite 200 Washington, D.C. 20002 U.S.A. Nicolas Rodríguez-Martinez Pemex Refinery Marina Nacional 329 Torte Piso 40 Huasteca 11300 Mexico City, Mexico

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX F

209

Julieta Rodríguez de Villamil Ministry of Health Carrera 7 #32-71 Piso 19 Santafe de Bogota Colombia

Arrieta Schnaas National Institute of Perinatology Monte Urales Sur 800 Lomas Virreyes C.P. 11000 Mexico City, Mexico

David Roe Environmental Defense Fund 5655 College Avenue Suite 304 Oakland, California 94618 U.S.A.

Kelly Scoggins National Institute of Public Health Av. Universidad 655 Col. Sta. María Ahuacatitlán 62508 Cuernavaca, Morelos, Mexico

Rosalba Rojas Office of Environmental Health San Luis Potosi 192 5th Floor Mexico City, Mexico

Lori Senini U.S./Mexico Border Health Department of Health Services 3851 Rosecrans Street San Diego, California 92138-5524 U.S.A.

Isabelle Romieu Pan American Center for Human Ecology and Health Rancho Guadalupe S/N Metepec, Edo. de Mexico Patricia Salomon Health Resources and Service Administration United States Public Health Service Bureau of Primary Health Care 4350 East West Highway Bethesda, Maryland 20814 U.S.A.

Kenneth Shine Institute of Medicine National Academy of Sciences 2101 Constitution Avenue, N.W. Washington, D.C. 20418 U.S.A. Ellen Silbergeld University of Maryland Medical School 660 W. Redwood Street Baltimore, Maryland 21201-1596 U.S.A.

Luz Helena Sanin Aguirre National Institute of Public Health Av. Universidad 655 Sta. Ma. Ahuacatitlán 62508 Cuernavaca, Morelos, Mexico

Carlos Eduardo Siqueira American Federation of State, County and Municipal Employees 1625 L Street, N.W. Washington, D.C. 20036 U.S.A.

Carlos Santos Burgoa National Institute of Public Health Av. Universidad 655 Sta. Ma. Ahuacatitlán 62508 Cuernavaca, Morelos, Mexico

Jerry Spiegel Manitoba Department of the Environment 139 Tuxedo Avenue Winnipeg, Manitoba, R3N 0H6 Canada

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

APPENDIX F

210

Delores Sutton Institute of Medicine National Academy of Sciences 2101 Constitution Avenue, N.W. Washington, D.C. 20418 U.S.A.

John Waraska ESA 22 Alpha Road Chelmsford, Massachusetts 01824 U.S.A.

Tania Tavares Institute of Chemistry Federal University of Bahia Campus Universitario da Federacao s/n Salvador 40210-340 Bahia, Brazil

Alan Whittingham Ethyl Corporation 330 South Fourth Street Richmond, Virginia 23217 U.S.A.

Sandra Guadalupe Treviño Siller National Institute of Public Health Av. Universidad 655 Sta. Ma. Ahuacatitlán 62508 Cuernavaca, Morelos, Mexico Francisco Vallecillos Cabello FONART-Lead Program Av. Patriotismo 691 Col. Mixcoac 03910 Mexico City, Mexico Enrique Valverde Duran Mining Industries of Mexico, S.A of C.V. Domicilio Conocido Col. Avalos Chihuahua, Mexico Cristina Von Glascoe El Colegio de la Frontera Norte Blvd. Abelardo L. Rodríguez 2925 Zona del Rio Tijuana, B.C., Mexico

David Wilson Lead Development Association 42 Weymouth Street London, England WIN 3LQ Leticia Yañez Estrada Universidad Autonoma Av. Venustiano Carranza 2405 78290 San Luis Potosi, Mexico Annalee Yassi University of Manitoba Department of Community Health Services S112-750 Bannatyne Avenue Winnipeg, Manitoba R3E 0W3 Canada Carmen Yris Delgado Pan American Health Organization Pepillo Salcedo No. 21 Santo Domingo Dominican Republic Manuel Yves Ministry of the Environment 14 Boulevard Du General Leclerc 92524 Neully-sur-seine-cedex Paris, France

Copyright © 1996. National Academies Press. All rights reserved.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please use the print version of this publication as the authoritative version for attribution.

This book was printed by Litoarte, S.A. de C.V., San Andrés Atoto 21-A, Col. Industrial Atoto, Estado de México, México, in February 1996. 500 copies were printed. Carlos Oropeza was responsible for editorial coordination.