Inhaling asbestos fibers can cause scar tissue (fibrosis) to form inside the lung. Scarred lung tissue does not expand and contract normally. The severity of the disease depends upon the duration of exposure to asbestos and the amount inhaled.

Asbestos fibers were commonly used in construction before 1975. Asbestos exposure occurs in asbestos mining and milling industries, construction, fireproofing, and other industries. In families of asbestos workers, exposure can also occur from particles brought home on the worker's clothing.

Asbestos-related disease includes pleural plaques (calcification), malignant mesothelioma, and pleural effusion. Mesotheliomas may develop 20 to 40 years after exposure. More than 9 million workers are at risk of developing this disease.

Cigarette smoking increases the risk of developing the disease. The incidence is 4 out of 10,000 people.

• Shortness of breath on exertion
• Cough
• Tightness in the chest
• Chest pain

Possible additional symptoms include the following:

• Nail abnormalities
• Clubbing of fingers

When listening to the chest with a stethoscope (auscultation), the health care provider may detect a crackling sound.

• Chest X-ray
• Pulmonary function tests
• CT scan of the lungs

There is no cure available. Stopping further exposure to asbestos is essential. Supportive treatment of symptoms includes respiratory treatments to remove secretions from the lungs by postural drainage, chest percussion, and vibration.

Aerosol medications to thin secretions may be prescribed. Oxygen by mask or by a plastic piece that fits into the nostrils may be needed.

• Malignant mesothelioma
• Pleural effusion