Strong concerns about the health hazards associated with asbestos had been described many times over the years. As early as 1898 the Chief Inspector of Factories of the United Kingdom reported to Parliament in his Annual Report about the "evil effects of asbestos dust". He reported the "sharp, glass like nature of the particles" when allowed to remain in the air in any quantity, "have been found to be injurious, as might have been expected" (Report of the Select Committee 1994). In 1906 a British Parliamentary Commission confirmed the first cases of asbestos deaths in factories in Britain and recommended better ventilation and other safety measures. In 1918 a US insurance company produced a study showing premature deaths in the asbestos industry in the United States and in 1926 the Massachusetts Industrial Accidents Board processed the first successful compensation claim by a sick asbestos worker. Many American injuries from asbestos exposure came from shipbuilders working during World War II.
The fine asbestos fibres are easily inhaled, and can cause a number of respiratory complaints, including a potentially serious lung fibrosis called asbestosis. Exposure to asbestos has also been determined to cause a very serious form of cancer, mesothelioma, that occurs in the chest and abdominal cavities. This aggressive disease is improperly referred to as a lung cancer, as the malignant cells are derived from the mesothelium, a tissue found on the inner walls of the chest and abdominal cavities and on the outer surface of the lungs rather than in the lung itself.
When inhaled, asbestos is carcinogenic (i.e. promotes cancer). In the United States alone, it is estimated that ten thousand people die each year of asbestos-related diseases, such as mesothelioma, asbestosis, lung cancer, and gastrointestinal cancer. Asbestos has a synergistic effect with tobacco smoking in the causation of lung cancer.