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 molybdenum in humans. Most molybdenum is used as the oxide to alloy steel. Other uses include as a lubricant, as catalysts, as pigments (especially molybdates), and in ceramics. Molybdenum has a very complicated chemistry, including valences from 0 to 6, nine oxides (white, red, violet, and black colors), multiple coordination numbers and other peculiarities. Molybdenum is generally distributed, with greatest concentrations in the kidney, liver, bones, and pancreas. Tissue levels are proportional to the dietary sulfate intake. The effects of molybdenum in humans include information on acute toxicity, chronic toxicity, biochemistry, specific organs and systems, teratogenicity, mutagenicity, and carcinogenicity. Molybdenum is a constituent of three metalloflavoproteins: xanthine oxidase, aldehyde oxidase, and sulfite oxidase.
