A variety of diseases caused by inhalation of asbestos fibres. Asbestos is a fibrous mineral formerly used as a heat- and fire-resistant insulating material. There are 3 main types of asbestos fibre: white, which is widely used; blue; and brown, the most dangerous. The use of all types is now carefully controlled. In asbestosis, widespread fine scarring occurs in the lungs. The disease causes breathlessness and a dry cough, eventually leading to severe disability and death. It develops mostly in industrial workers who have been heavily exposed to asbestos. The period from initial exposure to development of the disease is usually at least 20 years. Diagnosis is by chest X-ray. Asbestosis increases the risk of lung cancer. Mesothelioma is a cancerous tumour of the pleura (the membrane surrounding the lungs) or the peritoneum (the membrane lining the abdominal cavity). In the pleura, mesotheliomas cause pain and breathlessness; in the peritoneum they cause enlargement of the abdomen and intestinal obstruction. The condition cannot be treated and usually leads to death within 1 or 2 years. The average interval between initial exposure to asbestos and death is 20–30 years. Mesothelioma affects people who have worked with blue or brown asbestos. In diffuse pleural thickening, the outer and inner layers of the pleura become thickened, and excess fluid may accumulate in the cavity between them. This combination restricts the ability of the lungs to expand, resulting in shortness of breath. The condition may develop even after short exposure to asbestos.
Asbestos-related diseases |
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