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 barium in humans. Barium is produced by mining barite; the ore used is 75 to 98" barium. Ore-grade barite is found in many parts of North America, but Nevada supplies 50" of United States production. Over 90" of barium use is in the form of ground barite used in oil and gas well drilling. The rest is used to produce lithopone and barium chemicals. Soluble barium compounds are rapidly absorbed from the lungs and gastrointestinal tract. Insoluble compounds are not; hence barium sulfate is used as an x-ray contrast medium for gastrointestinal examination, despite its abominable chalky taste. The effects of barium in humans include information on acute toxicity, chronic toxicity, biochemistry, specific organs and systems, teratogenicity, mutagenicity, and carcinogenicity.
