Silica, silicosis, and lung cancer.

Evidence that crystalline silica is associated with an increased rate of lung cancer led the International Agency for Research on Cancer to conclude in 1997 that crystalline silica is a known human carcinogen. In Israel too, crystalline silica is considered as such. The decision raised a debate in the scientific arena, and a few scientists have questioned the basis upon which causality was determined. We review the literature regarding the level of evidence of crystalline silica carcinogenicity.