ABSTRACT
This chapter provides a detailed discussion on the occurrence and production, uses, chemical and physical properties, exposure and exposure limits, toxicokinetics, and effects of chromium in humans. The earth's crust contains an average 125 ppm chromium. Trivalent and hexavalent chromium are both found in nature, but Cr(III) predominates. Chromite, FeOCr2O3, is the only important chromium ore mineral. Chemical treatment of high carbon ferrochromium followed by electrolysis gives chromium metal. Chromium may also be produced by reduction of chromium compounds. Roasting chromite ore with soda ash or soda ash and lime gives impure sodium chromate and dichromate, the source of most other chromium compounds. Chromium compounds are used in tanning, pigments, and electroplating and as catalysts, corrosion inhibitors, and wood preservatives. The effects of chromium in humans include information on acute toxicity, chronic toxicity, biochemistry, specific organs and systems, teratogenicity, mutagenicity, and carcinogenicity.
