Abstract

The predominant asbestos fibre type used in the production of asbestos cement is chrysotile. The use of asbestos in relation to fibre type in a Norwegian asbestos cement plant during 1942-80 was 91.7% chrysotile, 3.1% amosite, 4.1% crocidolite, and 1.1% anthophyllite respectively. Electron microscopy and x ray microanalysis of lung tissue samples of asbestos cement workers who had died of malignant pleural mesothelioma or bronchogenic carcinoma showed a completely inverse ratio with regard to fibre type. The percentage of chrysotile asbestos in lung tissue varied between 0% and 9% whereas the corresponding numbers for the amphiboles were 76% and 99%. These differences are discussed with respect to the behaviour of different fibre types in the human body and to the occurrence of malignant mesothelioma in this asbestos cement factory.