Much of the more than 30 million tons of asbestos used in the United States since 1900 is still present as insulation in offices and schools, as vinyl-asbestos flooring in homes, and in other common products. This volume presents a comprehensive evaluation of the relation of these fibers to specific diseases and the extent of nonoccupational risks associated with them. It covers sources of asbestiform fibers, properties of the fibers, and carcinogenic and fibrogenic risks they pose.

Contents

• Committee on Nonoccupational Health Risks of Asbestiform Fibers
• Board on Toxicology and Environmental Health Hazards
• Preface
• Executive Summary
• 1. Introduction
  • Concurrent National Research Council and Government Activities Related to Asbestos
  • The Committee's Approach
  • References
• 2. Asbestiform Fibers: Historical Background, Terminology, and Physicochemical Properties
  • Asbestos in History
  • Mineralogical Terminology
  • Sources of Mineral Particles
  • Physical Properties of Asbestiform Fibers
  • Biologically Relevant Physicochemical Properties
  • Summary
  • Recommendations
  • References
• 3. Assessing Nonoccupational Exposures to Asbestiform Fibers
  • Definitions of Exposure
  • Asbestiform Fibers and Their Sources
  • Exposure Potential for Asbestos
  • Exposure to Other Natural Mineral Fibers
  • Exposure to Man-Made Fibers
  • Summary and Recommendations
  • References
• 4. Measurement of Exposure to Asbestiform Fibers
  • Measurement Techniques
  • Measuring Asbestos Dust in the Workplace
  • Measuring Asbestos Dust in the Ambient Environment
  • Relationships Among Various Exposure Measurement Methods
  • Exposure to Chrysotile in the Ambient Environment
  • Complicating Factors in Environmental Assays
  • Future Measurement of Exposure to Asbestiform Fibers
  • Recommendations
  • References
• 5. Effects of Asbestiform Fibers on Human Health
  • Nature of Evidence
  • Biodisposition of Fibers
  • Clinical Aspects of Asbestos-Associated Diseases
  • Disease Associated With Nonoccupational Inhalation Exposures to Asbestiform Fibers
  • Epidemiological Studies of Effects Resulting From The Ingestion of Asbestos in Drinking Water
  • Occupational Epidemiological Studies—Methodological Considerations
  • Cancer Mortality in Occupational Cohorts Exposed to Asbestos
  • Asbestosis and Asbestos-Associated Pleural Disease in Occupational Cohorts
  • Health Effects of Occupational Exposure to Man-Made Mineral Fibers
  • Additional Occupational Epidemiological Studies
  • Recommendations
  • References
• 6. Laboratory Studies of the Effects of Asbestiform Fibers
  • Studies In Animals
  • In Vitro Studies
  • Initiation-Promotion Model of Carcinogenesis
  • Conclusions
  • Summary
  • Recommendations
  • References
• 7. Risk Assessment
  • The Process of Risk Assessment
  • Quantitative Risk Assessment
  • Published Risk Assessments
  • Quantitative Risk Assessment for Nonoccupational Environmental Exposures
  • Comparative Risk Assessment
  • Summary and Recommendations
  • References
• Appendix A Asbestos Exposure and Human Disease. Hallmark Observations and Studies From 1898 to 1979
• Appendix B Natural and Synthetic Fibrous Substances and Some of their Known Biological Effects
• Appendix C Fiber-Quality Parameters of Selected Asbestos, Whisker, and Glass Fibers
• Appendix D Conceptual Model of Fiber Exposure
• Appendix E Epidemiological Studies Among Cohorts Exposed To Asbestos
• Appendix F Effects of Administering Asbestiform Fibers to Animals
• Appendix G Development of Some Equations Used for Quantitative Risk Assessment
• Appendix H Comparative Risk Assessment Score Sheets
• Appendix I Background Information on Members of the Committee on Nonoccupational Health Risks of Asbestiform Fibers

The study reported here was supported by Contract EPA 68-01-4655 between the National Academy of Sciences and the Environmental Protection Agency.

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 competences and with regard for appropriate balance.

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 National Research Council was established by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy's purposes of furthering knowledge and of advising the federal government. The Council operates in accordance with general policies determined by the Academy under the authority of its congressional charter of 1863, which establishes the Academy as a private, nonprofit, self-governing membership corporation. The Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in the conduct of their services to the government, the public, and the scientific and engineering communities. It is administered jointly by both Academies and the Institute of Medicine. The National Academy of Engineering and the Institute of Medicine were established in 1964 and 1970, respectively, under the charter of the National Academy of Sciences.