Mesothelioma- Other Causes

Radiation
There have been a few published reports of lung and stomach mesotheliomas that developed following exposure to Thorotrast.  This material was used by doctors for certain x-ray tests.  Because Thorotrast was found to cause cancers, it has not been used for many years.

Zeolite
This is a mineral, chemically related to asbestos, common in the soil of the Anatoli region of Turkey.  Many cases of mesothelioma have been described in this region and may have been caused by this mineral.

Tobacco
Although tobacco smoking has not been associated with developing mesothelioma, the combination of smoking and asbestos exposure greatly increases the risk of lung cancer. 
Smoking does not appear to increase the risk of mesothelioma.  However, the combination of smoking and asbestos exposure significantly increases a person’s risk of developing cancer of the air passageways in the lung.

SV40 Virus
Recent studies have raised the possibility that infection with simian virus 40 (SV40) might increase the risk of developing mesothelioma. Some injectable polio vaccines available between 1955 and 1963 were contaminated with SV40.
So far, the largest studies addressing this issue in humans have not found any increased risk for mesothelioma or other cancers among people who received the contaminated vaccines as children. The peak age range for diagnosis of mesothelioma is 50 to 70 years old.  Some researchers have pointed out that this issue may remain unresolved until more of the people accidentally exposed to SV40 between 1955 and 1963 reach that age range.  Research into this is still underway.