Abstract
The current standard for occupational exposure to asbestos is 2 fibers/cm3 averaged over an 8-hr day. A NIOSH/OSHA committee has recently concluded that the 2 fiber/cm3 standard is grossly inadequate to protect workers from asbestos-related disease, and that all levels of asbestos exposure studied thus far have demonstrated asbestos-related disease. The committee recommends that a 0.1 fiber/cm3 limit replace the current 2 fiber/cm3 standard on the grounds that this is the lowest level detectable with currently available analytical techniques. Thus a 0.1 fiber/cm3 limit is not based on epidemiological data but on the presumption that any level of exposure is disease producing. This paper addresses the question of whether it would be possible to detect health effects of exposure below the current 2 fiber/cm3 standard. Five studies are reviewed which provide evidence on the strength of the relationship between asbestos fiber exposure and lung cancer. Calculation of sample sizes needed to be 95% certain of detecting the kind of excess probably associated with exposure to 2 fibers/cm3 suggests that epidemiology is not likely to be useful in detecting lung cancer below the current standard. Some outcome measures other than lung cancer or clinical asbestosis will be needed if observations on humans are to be used as evidence for a lowering of the present standard.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Becklake M. R. Asbestos-related diseases of the lung and other organs: their epidemiology and implications for clinical practice. Am Rev Respir Dis. 1976 Jul;114(1):187–227. doi: 10.1164/arrd.1976.114.1.187. [DOI] [PubMed] [Google Scholar]
- McDonald J. C., Liddell F. D., Gibbs G. W., Eyssen G. E., McDonald A. D. Dust exposure and mortality in chrysotile mining, 1910-75. Br J Ind Med. 1980 Feb;37(1):11–24. doi: 10.1136/oem.37.1.11. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Peto J., Doll R., Howard S. V., Kinlen L. J., Lewinsohn H. C. A mortality study among workers in an English asbestos factory. Br J Ind Med. 1977 Aug;34(3):169–173. doi: 10.1136/oem.34.3.169. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Peto J. Lung cancer mortality in relation to measured dust levels in an asbestos textile factory. IARC Sci Publ. 1980;(30):829–836. [PubMed] [Google Scholar]
- Roach S. A. Hygiene standards for asbestos. Ann Occup Hyg. 1970 Jan;13(1):7–15. doi: 10.1093/annhyg/13.1.7. [DOI] [PubMed] [Google Scholar]
- Weill H., Hughes J., Waggenspack C. Influence of dose and fiber type on respiratory malignancy risk in asbestos cement manufacturing. Am Rev Respir Dis. 1979 Aug;120(2):345–354. doi: 10.1164/arrd.1979.120.2.345. [DOI] [PubMed] [Google Scholar]