The particle that never leaves
Not all dust is equal. The dust raised by a jackhammer breaking concrete, a grinder cutting sandstone, or a drill boring through brick contains crystalline silica, particles that measure between 0.5 and 10 microns. At that size, they do not get caught in the nose or throat. They travel to the alveoli, the tiny air sacs at the base of the lungs where oxygen crosses into blood. Once silica lands there, the body's immune cells rush to destroy it. They can't. Silica is chemically inert. The immune cells die trying, release inflammatory signals, and the cycle repeats. Over months and years, that repeated inflammation lays down scar tissue. The medical name is silicosis. The scar tissue does not reverse.
