Asbestiform fibers : nonoccupational health risks

Asbestiform Fibers
Copyright
Preface
References
Contents
Executive Summary
ORIGIN OF THE STUDY
MAJOR FINDINGS AND RECOMMENDATIONS
Evaluation of Risk
Physicochemical Properties and Health Effects
Recommendations
SUMMARY OF THE STUDY
Background
Materials of Concern
Relationship of Fiber Characteristics to Health Effects
Measurement and Extent of Exposure
Health Effects Methodology
Health Effects of Asbestos
Health Effects of Nonasbestos Asbestiform Fibers Evidence Associating Fiber Properties with Adverse Health EffectsRisk Assessments
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
Fiberlike Morphology
Enhanced Strength and Flexibility
Diameter-Dependent Strength Increased Physical and Chemical DurabilityDefect-Free Surface Structure
Growth-Dependent Fiber Quality
BIOLOGICALLY RELEVANT PHYSICOCHEMICAL PROPERTIES
Respirability
Size and Aspect Ratio (Length:Diameter)
Durability
Flexibility and Tensile Strength
Chemical Composition
Surface Area
Surface Charge
Standardized Asbestos Samples
SUMMARY
RECOMMENDATIONS
REFERENCES
3 Assessing Nonoccupational Exposures to Asbestiform Fibers 
DEFINITIONS OF EXPOSURE
ASBESTIFORM FIBERS AND THEIR SOURCES EXPOSURE POTENTIAL FOR ASBESTOSTypes of Exposure
Quantitative Exposure Estimates
EXPOSURE TO OTHER NATURAL MINERAL FIBERS
Attapulgite
Erionite
EXPOSURE TO MAN-MADE FIBERS
Man-Made Mineral Fibers
Exposure to Other Man-Made Fibers
SUMMARY AND RECOMMENDATIONS
REFERENCES
4 Measurement of Exposure to Asbestiform Fibers 
MEASUREMENT TECHNIQUES
MEASURING ASBESTOS DUST IN THE WORKPLACE
The Impinger Technique
The Membrane Filter Technique
MEASURING ASBESTOS DUST IN THE AMBIENT ENVIRONMENT RELATIONSHIPS AMONG VARIOUS EXPOSURE MEASUREMENT METHODSEXPOSURE 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
Fiber Deposition
Clearance and Transport
CLINICAL ASPECTS OF ASBESTOS-ASSOCIATED DISEASES
Necessary Assumptions Used in Determining Health Effects
Sensitivity and Specificity of Clinical Evidence