Asbestos is the collective name for a group of naturally occurring silicates (which are a type of mineral) whose heat-resistant and structural properties are useful in construction and insulating and other materials on board ships, in automobile brakes, and in some textiles.
In most developed countries, asbestos use has declined over the past several decades, but asbestos can still be found in old building materials and some products. More widespread asbestos use continues primarily in some developing countries. Because it takes a long time to develop disease after being exposed to asbestos, people continue to develop asbestos-related disease.
Prior occupational exposure remains the predominant cause of asbestos-related disease. Asbestos is also present in low levels in the air, water, and soil, but this low level of environmental exposure is generally not a significant contributor to human disease.
Asbestos-related disorders are caused by inhalation of asbestos fibers, such as when brittle or fragile material that contains asbestos is disturbed. Asbestos can cause nonmalignant and malignant disease.
Nonmalignant (noncancerous) disease includes
Benign asbestos pleural effusion (BAPE)
Asbestosis is a form of interstitial lung disease caused by asbestos exposure.
Asbestos-related pleural plaques are the most common manifestation of asbestos exposure. (The pleura is the thin tissue that lines the lungs.) The time it takes for asbestos-related pleural plaques to develop after the person is exposed to asbestos is approximately 20 to 30 years. Often pleural plaques cause no symptoms, although because the plaques result from asbestos exposure, they increase the risk of other asbestos-related lung disease.
Asbestos-related pleural thickening is characterized by widespread, extensive thickening of the pleura. Pleural thickening can cause shortness of breath and chest pain.
Benign asbestos pleural effusions (BAPE) are small and bloody pleural effusions that affect one side of the lungs. These effusions generally occur within 10 years of exposure to asbestos. A person with BAPE may have no symptoms, or they may have fever and chest pain.
Malignant (cancerous) disease includes
Lung cancer is the most common type of cancer associated with asbestos exposure. The time from exposure to disease onset is typically 20 to 30 years. Risk of lung cancer due to asbestos exposure increases with larger cumulative exposures. Though asbestosis is an indicator of high-level exposure, lung cancer can occur without asbestosis. Smoking increases the risk of lung cancer in people who have been exposed to asbestos.
Mesothelioma, a malignant tumor of the pleura and/or peritoneum, is characterized by a long latency (time from exposure to disease onset), with a median of approximately 40 years. Although most mesotheliomas are occupational in origin, they can also develop after environmental exposure or take-home exposure (such as when a worker brings asbestos home through contaminated belongings).
(See also Overview of Environmental and Occupational Lung Disease.)
