Authors' reply to letters from Egilman et al and Oliver et al

Dr Egilman and colleagues claim our report1 implies that chrysotile does not cause mesothelioma. So did the International Chrysotile Association, the website of which highlighted our paper with the misleading headline ‘reliable scientific data confirms negligible role of chrysotile in UK patients with asbestos-related lung disease’.2 Our results are consistent with the strong evidence that chrysotile did not cause a large proportion of UK mesotheliomas, but they certainly do not show that the risk is negligible. We said ‘the rapid clearance of chrysotile from the lung with a half-life of a few months explains its virtual absence in our samples, and implies that we cannot estimate its effects except by noting that amphibole lung burdens account very well …