As for other environmental factors, one of the most significant among them is the exposure to asbestos fibers and similar materials. Usually, a person is exposed to these silicate materials at the workplace: technical works such as thermal and acoustic insulation involve the usage of asbestos. Nowadays, asbestos is limited or even prohibited from usage, since it has been proven that asbestos materials can cause both lung cancer and mesothelioma (cancer of the lungs’ pleura, as well as cancer of peritoneum – a lining of the abdominal cavity). Even non-smoking asbestos workers have a five times higher risk of developing lung cancer; as for the smoking asbestos workers, their chances to get cancer are up to ninety-fold greater than nonsmokers (MedicineNet.com