Silicosis is a lung disease (pneumopathy) caused by inhaling dust, specifically silica dust (SiO2). It is therefore a pneumoconiosis.
This occupational disease is particularly known as miner's disease as it affects workers continuously exposed to silicone dust and charcoal produced by activities in mines.
Silicosis presents after exposure for 10 to 30 years and causes progressive, irreversible deterioration of respiratory capacity as a result of chronic inflammation and growth of scar tissue (pulmonary fibrosis).
Mechanism of silicosis
At a cellular level, the silica dust is absorbed by pulmonary mucosal phagocytes. The mineral particles in these cells tear the lysosomes, releasing their enzymes into the cytosol, killing the cell.
The dead hyalinised cell bodies (which become glassy in appearance due to the accumulation of silica), and a large amount of dust then destroy the pulmonary vessels, causing chronic inflammation.
This scar tissue, which reduces the elasticity and effectiveness of the lungs, leads to pulmonary fibrosis that then progresses to oversecretion of mucus (bronchitis) and destruction of the alveoli and peri-alveolar structures (emphysema).
There is no known effective treatment, hence the importance of prevention.
Workers are exposed to fine silica dust in mines, quarries and glass-making factories. Unless adequately protected, these dusts cause a lung disease, silicosis. © cbing73 CC by-nc-nd 3.0