National Toxicology Program

National Toxicology Program

Scientific Review of Silica, Crystalline (Respirable Size)

CASRN 7631-86-9
Status: Listed in the Report on Carcinogens (RoC)

Primary Uses or Exposures: Crystalline silica is an abundant and commonly found natural material. Human exposure to respirable crystalline silica, primarily quartz dusts, occurs mainly in industrial and occupational settings. Respirable quartz levels exceeding 0.1 mg/m 3 are most frequently found in metal, nonmetal, and coal mines and mills; in granite quarrying and processing in crushed stone and related industries; in foundries; in the ceramics industry; in construction; and in sandblasting operations.

Background Document

Public Comments


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