TOXICOLOGICAL PROFILE FOR CHROMIUM - Davidborowski.com

CHROMIUM 1682. HEALTH EFFECTS2.5 RELEVANCE TO PUBLIC HEALTHIssues relevant to children are explicitly discussed in Sections 2.7, Children’s Susceptibility, and 5.6,Exposures of Children.Overview.Chromium(III) is an essential nutrient required for normal energy metabolism. The National ResearchCouncil (NRC) recommends a dietary intake of 50–200 µg/day (NRC 1989). The biologically activeform of an organic chromium(III) complex, often referred to as GTF, is believed to function byfacilitating the interaction of insulin with its cellular receptor sites. The exact mechanism of thisinteraction is not known (Anderson 1981; Evans 1989). Studies have shown that chromiumsupplementation in deficient and marginally deficient subjects can result in improved glucose, protein,and lipid metabolism.Evidence of overt signs of chromium deficiency in humans is limited to a few case reports. In one suchcase report, a woman receiving total parenteral nutrition for 3 years exhibited peripheral neuropathy,weight loss, and impaired glucose metabolism. Administration of insulin did not improve glucosetolerance. Administration of 250 µg/day chromium without exogenous insulin resulted in normal glucosetolerance of an oral load of glucose and the absence of peripheral neuropathy (Jeejeebhuoy et al. 1977).In animals, severe chromium deficiency has resulted in hyperglycemia, decreased weight gain, elevatedserum cholesterol levels, aortic plaques, corneal opacities, impaired fertility and lethality. Administrationof inorganic trivalent chromium compounds or extracts of brewers' yeast resulted in decreased bloodglucose levels and cholesterol levels and regression of atherosclerotic plaques (Pi-Sunyer andOffenbacher 1984). Improved insulin sensitivity also resulted in an increased incorporation of aminoacids into proteins and cell transport of amino acid in rats receiving supplemental chromium (Roginskiand Mertz 1969).Although the incidence of severe chromium deficiency is low, the occurrence of marginal chromiumdeficiency may be common. Studies have shown that the daily dietary intake of chromium in the UnitedStates is 25–224 µg/day, with an average of 75 µg/day (Kumpulainen et al. 1979). An average dailyintake of 60 µg has been reported by Bennett (1986). Numerous studies have been designed to determinethe effect of chromium supplementation in individuals exhibiting abnormal glucose tolerance and/or