The Size Distribution of Airborne Bolivian Crocidolite FibersBack to list
Current Environmental Protection Agency (EPA) risk models and asbestos fiber counting techniques for monitoring airborne exposures treat all fibers as being equivalent and ignore the effect of dimension on toxicity. While this may have been appropriate when modern analytical methods were not available, the measurement world is now fully capable of making the appropriate distinctions. The importance of width as a determinant of carcinogenicity has been recognized for nearly 30 years within the published literature. Stanton,1 in a landmark study of a suite of fibrous materials, found that durable mineral fibers with widths less than 0.25 µm and lengths longer than 8 µm were causally associated with the induction of tumors. Pott,2 in a later study, postulated a fiber toxicity model that agreed reasonably well with the Stanton findings, but extended the concept to include varying toxicity as a function of length and width. Wylie et al3 reanalyzed samples used by Davis et al4 and found that tumor generation was strongly and inversely correlated with fiber width. Crump5 testified increasing fiber length was correlated with disease occurrence. Lippman6 reviewed a number of studies and suggested that mesothelioma was closely associated with long, thin fibers. Berman et al7 published a risk model, which found that disease was correlated almost exclusively with fibers longer than 40 µm and width less than 0.25 µm. Recently, Loomis et al8 reanalyzed textile mill samples and found that aspect ratios greater than 40:1 were highly correlated with disease.
- Bronchoalveolar Lavage in Interstitial Lung Disease
- The Value of Pulmonary Function Testing in Bone Marrow Transplantation
- Different Radiographic Presentation of Secondary Pneumomediastinum Is Related to a Higher Severity of Disease/Treatment Outcome
- Noninvasive Ventilation for Weaning and Post Extubation Failure
- Clinical Features, Burden, and Risk Factors for Chronic Obstructive Pulmonary Disease in Nonsmokers