Scientific study on different effects between the two groups of asbestos

A comparative scientific study evaluating exposure, dose-response and fate in the lung and pleura of chrysotile-containing brake dust confirms the major differences between the toxicology of chrysotile fibers and that of other asbestos fibers.

This rigorous, 90-day repeated dose inhalation study of brake dust in rats provides a comprehensive understanding of the biokinetics and potential toxicology in the lung. It included a particle control on chrysotile, commercial crocidolite and amosite asbestos. The interim results have shown an important fundamental difference in persistence and pathological response in the lung between brake dust derived from brake-pads manufactured with chrysotile, TiO2 or chrysotile alone in comparison to the amphiboles, crocidolite and amosite asbestos. In the brake dust exposure groups, no significant pathological response was observed at any time. Chrysotile, being biodegradable, showed a weakening of its matrix and braking into short fibers and particles that can be cleared by alveolar macrophages and continued dissolution.

In comparison, both crocidolite and amosite induced persistent inflammation, microgranulomas and fibrosis which persisted through the post exposure period. The seven-member team of international researchers led by D.M. Bernstein published its two-part research in Elsevier’s online Toxicology and Applied Pharmacology journal in December 2019. Another article, detailing subsequent results through life-time post exposure, will follow.

Chrysotile Association