Mesothelioma is most commonly caused by?

Ans. (a) AsbestosisRef: Harrison 19th ed. /1689* Working with asbestos is the most common risk factor for mesothelioma.* Indeed, the relationship between asbestos and mesothelioma is so strong that many consider mesothelioma a "signal" or "sentinel" tumor.* In rare cases, mesothelioma has also been associated with irradiation of the chest or abdomen, intrapleural thorium dioxide (thorotrast) as a contrast medium, and inhalation of other fibrous silicates, such as erionite.