On exposure to asbestos, the larger fibers are filtered in the nasal passage and the upper airways. The minute fibers, in the size range of 3 µm, penetrate the lower airways of the lungs. These fibers are recognized as foreign agents and are, therefore attacked by the
When the macrophage engulfs the fibers, they get destroyed due to the size of these fibres. The entry of more macrophages to attack the free fibre releases
As a result of damage, the lung tissue gets fibrosed. Initially, the damage is localized and confined to a small area, The person then starts developing symptoms of lung disease. As the exposure to asbestos continues, the fibrosis extends and sometimes the entire lung becomes scarred.
Scarring of the alveoli or air sacs leads to respiratory distress in the affected individuals.
- Harrison's Textbook of Medicine Cecil's Textbook of Medicine - (https://www.who.int/)