Changes

Eventually, the doctors realized that their patients had lied to them because there was a social stigma attached to working with asbestos. The patients had worked in and around asbestos but were loath reluctant to admit. Eventually, patients began to reveal that they had worked in asbestos mines or mills. In some cases, these patients described living in "a blue haze" in their communities that were located next to mines and mills. The mills and mines west of Kimberly worked with blue asbestos.<ref>Wagner, J.C., "The discovery of the association between blue asbestos and mesotheliomas and the aftermath," <i>British Journal of Industrial Medicine</i>, 1991; 48:399-403 and Tannapefel, <i>Malignant Mesothelioma</i>, p. 15.</ref>

In order to To determine if asbestos was the cause, the physicians had an unlikely incredible resource. The South African Pneumoconiosis Bureau had to keep records and samples of the thoracic organs of most of the miners who had died. The South African government had already determined that working with asbestos was dangerous, but they did not know exactly precisely why. On the other hand, mining companies were not interested in delving too deeply into why their miners died. The physicians were allowed to review realized after reviewing these samples and learned that miners exposed to amosite (blue) and occasionally chrysolite asbestos developed fatal pleura tumors. After further study, it became clear that all types of asbestos could cause cancer, but some types of asbestos were much more dangerous. It was also confirmed that cigarette smokers who were exposed to asbestos faced even higher risks of developing mesothelioma.<ref>Wagner, J.C.,"The discovery of the association between blue asbestos and mesotheliomas and the aftermath," <i>British Journal of Industrial Medicine</i>, 1991; 48:399-403: 433.</ref>

Eventually, physicians would establish established that tradesmen that worked around asbestos were also exposed to enough to cause mesothelioma. Oftentimes Frequently in these cases, the disease would develop much later than those who worked in the mills or asbestos mines. Workers who built ships for the US Navy were often exposed to large amounts of asbestos because it was used to make the naval ship more fireproof.<ref>Tannapfel, <i>Malignant Mesothelioma</i>, p. 16. </ref>