It is a disease in which asbestos fibers become deposited in the lungs, causing an inflammatory reaction followed by hardening of the affected area(no longer functional). With repeated exposure to asbestos, the lungs become increasingly damaged, causing a reduction in the amount of air that can enter the lungs. This will most likely cause fatigue and in the later stages, a lack of oxygen.
Long-term exposure to asbestos is also a potential cause of mesothelioma, a very aggresive form of cancer, affecting the pleura(a membrane on the outside of the lungs and innermost chest wall). Lung cancer can also be caused by asbestos.
Asbestos is a widely used material, because of its great resistance to heat and endurance. It can be found in car disk breaks, fire walls, some types of roofs etc. Asbestosis is usually an occupational disease, affecting workers directly exposed to asbestos.