Asbestos is a commercially relevant group of strong, ductile, and fire-resistant mineral fibers.
These properties, which differ among different mineralogic types of asbestos, strongly affect its in vivo persistence and toxicity. Chrysotile asbestos constitutes approximately 99 percent of airborne asbestos fibers in the general environment. Various regulatory agencies have estimated the risk of cancer from low asbestos exposure by extrapolating from the data for high asbestos exposure. The EPA model, applied to the measured asbestos concentrations in the local air, predicts approximately 75 excess deaths from lung cancer in the mining-area population. All have been shown in clinical, epidemiologic, and laboratory studies to be fully capable of causing lung cancer, mesothelioma, and the full range of asbestos-related diseases.