Asbestosis is a respiratory disease that occurs due to prolonged exposure to asbestos. Asbestos is a fibrous mineral that prior to the 1970s was used in a variety of products, including vehicle brakes and building materials. The fibers in asbestos can separate, become airborne and be inhaled by those working with the material. Symptoms of asbestosis may not appear for 20 to 30 years after exposure, according to the Mayo Clinic, and range from mild to severe. Typical symptoms include shortness of breath, coughing and chest pain; however, additional complications can arise.
Pulmonary Hypertension
Once the asbestos fibers are inhaled, they travel through the trachea, into the bronchi and enter the lungs. Normally, foreign objects are caught by the hairs of the nose or the cilia (tiny hairs) in the bronchi. The asbestos fibers, however, are too large to be trapped. The alveoli, the small sacs in the lungs responsible for exchanging oxygen and carbon dioxide, have a second line of defense against foreign invaders. Macrophages, a type of white blood cell, attack any invaders neutralizing them before they can cause trouble. Because asbestos fibers are large, the macrophages cannot engulf them entirely, which causes the fluid from the macrophage to leak into the alveoli. This causes damage to the lung tissue which results in scar tissue.
Over time this scar tissue builds-up and decreases the lungs ability to expand and contract reducing its effectiveness in gas exchange. The scar tissue causes additional pressure in the blood vessels in the lungs, which causes high blood pressure in the lungs, a condition known as pulmonary hypertension.
Heart Problems
The pulmonary hypertension causes the pulmonary artery, the vessel that leads from the heart to the lungs, to narrow. As the heart contracts, the right ventricle (the bottom chamber of the heart) pumps oxygen-poor blood into the lungs to receive oxygen. When the artery becomes narrower, the heart must pump harder to push the blood to the lungs. At first, the right ventricle will increase its capacity to hold blood, since less is able to move through the pulmonary artery, but as the condition continues, this portion of the heart will become weak and eventually fail.
Lung Cancer
Exposure to asbestos increases the risk of developing lung cancers, including a rare form of cancer called mesothelioma. Those with asbestosis are at an even higher risk, as reported by the journal “Chest.” The scar tissue in the lungs created by the asbestos fibers allows the lungs to trap and hold dangerous and toxic substances, including cigarette smoke which also contributes to cancer.
