The association of mesothelioma, a lethal lung disease, with asbestos has led to an absolute ban on asbestos in at least 55 countries worldwide. The purpose of this paper is to review residual exposure to asbestos as well as other emerging causes of mesothelioma outside asbestos. The review provides detailed description of asbestos minerals, their geographical locations, mesothelioma in these areas, as well as contemporary possible sources of asbestos exposure. Second, we examine other emerging causes of mesothelioma including: ionizing radiation as the second most important risk factor after asbestos, particularly relevant to patients undergoing radiotherapy, third, carbon nanotubes which are under investigation and fourth, Simian virus 40. In the case of asbestos per se, the greatest risk is from occupational exposure during mining and subsequent processing. Of the non-occupational exposures, environmental exposure is most serious, followed by exposure from indoor asbestos minerals and secondary familial exposure. Overall, asbestos is still a major risk factor, but alternative causes should not be neglected, especially in young people, in women and those with a history of radiotherapy or living in high-risk locations.
Keywords: asbestos; mesothelioma; non-asbestos etiology; non-occupational exposure; occupational exposure.