Type of Asbestos and Respiratory Cancer in the Asbestos Industry

Differences in the physical properties and chemical composition of the various types of asbestos indicate that there should be differences in their carcinogenic potentials. This study of the mortality experience of 1,348 retirees from the asbestos industry shows that, after adjustment for cumulative dust exposure, men exposed only to chrysotile asbestos had a respiratory cancer mortality rate 2.4 times the expected, whereas men exposed to a combination of chrysotile and crocidolite asbestos had a mortality rate 5.3 times the expected. Since crocidolite was used largely in the asbestos cement industry, this was studied separately. Men who manufactured asbestos cement shingles and sheets containing only chrysotile asbestos had a respiratory cancer risk 1.4 times the expected, whereas men who manufactured asbestos cement pipe containing both chrysotile and crocidolite asbestos had a respiratory cancer risk 6.1 times the expected.