Nickel is found in nature as a component of silicate, sulfide, or, occasionally arsenide ores. It is a valuable mineral commodity because of its resistance to corrosion. Uses for nickel and its compounds include nickel alloys, electroplating baths, batteries, textile dyes and mordants, and catalysts. The predominant forms of nickel in the atmosphere are nickel sulfate, nickel oxides and complex oxides of nickel. Nickel is also found in ambient and drinking waters and soils as a result of both natural and anthropogenic sources. Routes of nickel intake for man and animals are inhalation, ingestion and percutaneous absorption. The pulmonary absorption of nickel compounds varies according to chemical and physical form, with insoluble compounds generally being cleared more slowly. Gastrointestinal intake of nickel by man is relatively high ranging from 300 to 500 micrograms daily; however, absorption is low, averaging one to ten percent of intake. Percutaneous absorption of nickel often occurs through contact with nickel-containing commodities used in food preparation; such contact is related to hypersensitivity and skin disorders. Absorbed nickel is carried by the blood and distributed to various tissues depending on route of intake. Inhaled nickel compounds lead to highest levels in lung, brain, kidney and liver. In humans, age-dependent accumulation appears to occur only in the lung. Unabsorbed dietary nickel is lost in the feces; urinary excretion is the major clearance route for absorbed nickel.

"Final report." Distributed to depository libraries in microfiche. "September 1985." Includes bibliographies. "EPA/600/8-83/012F."