Perelman School of Medicine at the University of Pennsylvania


What is the Link Between Asbestos Exposure and Health Problems?

Asbestos exposure can cause a number of health problems. Asbestos fibers are easily inhaled and if one breathes in the fibers over long periods of time, the risk of asbestosis, lung cancer and mesothelioma increases. Fibers are carried into the lower regions of the lung where they can cause fibrotic lung disease and changes in the lining of the chest cavity or pleura. Smoking increases the risk of asbestos related health problems since it irritates lung passages making it harder for the lungs to remove asbestos fibers. Some of these health problems include:

Asbestosis which is scarring in the lungs caused by breathing asbestos fibers. Fibers become trapped in the lung tissue causing scarring which makes breathing harder due to impaired gas exchange. Asbestosis usually occurs in people who have had very high exposures over a long time, but years may pass before any symptoms appear.

Pleural disease is a non-cancerous lung condition that’s caused from thickening in the pleura which is the membrane surrounding the lungs and chest cavity. Diffuse pleural thickening occurs when thickening occurs throughout the pleura or in isolated areas (pleural plaques), or fluid may build up around the lungs (known as a pleural effusion).

Lung cancer occurs when asbestos fibers cause enough irritation, inflammation and genetic damage, tumor formation begins. Smoking tobacco combined with asbestos exposure greatly increases the chance of developing lung cancer. Lung cancer develops long after asbestos fibers have reached the lungs and typically takes 15 to 35 years to develop.

Mesothelioma is a rare cancer of the pleura, a membrane that covers the lungs and chest cavity (pleura), the membrane lining the abdominal cavity (peritoneum), or membranes surrounding other internal organs. This form of cancer is only known to be caused from asbestos exposure.  Signs of mesothelioma may not appear until 30 to 40 years after exposure to asbestos.

How exposure to asbestos fibers is measured

Asbestos fiber length is important in determining the impact on health from airborne exposure. Fibers with lengths greater than 5.0 µm are more likely to cause injury than fibers with lengths less than 2.5 µm.  Short fibers can also contribute to injury, however, fibers thicker than 3.0 µm are of lesser concern, because they have little chance of penetrating to the lower regions of the lung.