The different forms of natural crystalline silica appear in nature in large quantities in rock, sand and clay. A large percentage of the earth’s crust contains silica.
Many activities in mining, construction or quarries result in the release of respirable crystalline silica particles.
It has long been known that inhaled RCS particles cause scar tissue inside the lung, reducing the gas transfer to and from the blood. This can result in chronic bronchitis or an irreversible, deadly silicosis.