The only recognized cause of mesothelioma is exposure to asbestos, though other factors such as smoking can make mesothelioma more or less likely in some individuals. Industrial laborers were widely subjected to asbestos exposure on the job, as the material was widely used throughout the 20th century.
Few of these workers knew they were being exposed to asbestos and thus put at risk for mesothelioma, however, despite the fact that many manufacturers were aware the material was hazardous.
