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 zirconium in humans. The crustal abundance of zirconium has been variously estimated at 160 to 280 ppm. Zirconium is a constituent of numerous rocks including granular limestone and granite. The silicate zircon is its most abundant and widely distributed mineral; baddeleyite is the next most important mineral. In the United States, zirconium is recovered as a by-product of titanium production from beach sands. Numerous states have zircon deposits. Zirconium also appears in the wastes from processing bauxite and phosphate rock. The major purification process is the Kroll process, in which ZrCl4 is reduced by Mg. The effects of zirconium in humans include information on acute toxicity, chronic toxicity, biochemistry, specific organs and systems, teratogenicity, mutagenicity, and carcinogenicity.
