Chrysotile biopersistence: the misuse of biased studies.

Although it is widely accepted that exposure to any asbestos type can increase the likelihood of lung cancer, mesothelioma, and non-malignant lung and pleural disorders, manufacturers and some chrysotile miners' unions contend that chrysotile either does not cause disease or that there is insufficient evidence to reach a conclusion. At the same time, Dr. D.M. Bernstein has published several animal studies, financed by the Québec Chrysotile Institute, to determine chrysotile biopersistence in the lungs. Bernstein's study protocol induces a very short fiber half-life, from which he concludes weak chrysotile carcinogenicity. Bernstein's findings contradict results obtained by independent scientists. Bernstein's results can only be explained by an aggressive pre-treatment of fibers, inducing many faults and fragility in the fibers' structure, leading to rapid hydration and breaking of long fibers in the lungs.