Working with asbestos is a MAJOR risk factor for mesothelioma. A history of asbestos exposure exists in most cases. Although it could be caused by other things as well.
In some cases, mesothelioma is associated with irradiation, intrapleural thorium dioxide (Thorotrast), and inhalation of other fibrous silicates, such as erionite. Some suggest that the simian virus 40 (SV40) may act as a cofactor in the development of mesothelioma.
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