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Abstract

This short report continues and summarizes previously published articles. Asbestos-related risks have been estimated on the basis of extrapolations from the past, when high-dose exposures were more frequent. The linear nothreshold dose-response pattern has been assumed for low exposure levels although its applicability has never been proven. Inhalation and discharge of fibers are normally in a dynamic equilibrium. Accordingly, there may be a safe exposure level (threshold). The screening bias probably contributed to the enhanced registered incidence of asbestos-related diseases in exposed populations. In particular, mesothelioma was sought in exposed populations and correspondingly more often found. Malignant mesothelioma is indistinctly demarcated as an entity; in asbestos-exposed populations, questionable or borderline cases can be diagnosed as mesothelioma. Furthermore, carcinogenicity of chrysotile vs. amphibole asbestos is discussed. Research on this topic has been influenced by economic interests. Chrysotile clearance from the lung may partly result fromthe fiber splitting and movement to the pleura. A possible way to objective information can be large-scale chronic bioassays. In conclusion, the asbestos-related policies should be revaluated on the basis ofindependent research.