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 calcium in humans. Calcium metal is always found combined in compounds in nature. The principal commercial source of calcium is limestone. Calcium is produced by electrolysis of CaCl2 and by the thermal reduction of limestone by Al or Si. Calcium chloride is recovered from natural salt brines and is a by-product of the ammonia soda (Solvay) process. Calcium metal is used in metallurgy as a deoxidizer for Cu, Be, and steel (with Si), to harden lead for bearings, and to alloy Ce for flints. Principal uses of CaCl2 are for melting ice and snow, to accelerate concrete setting, and to settle dusts on unpaved roads. The effects of calcium in humans include information on acute toxicity, chronic toxicity, biochemistry, specific organs and systems, teratogenicity, mutagenicity, and carcinogenicity.
