TOXICOLOGICAL PROFILE FOR CHROMIUM - Davidborowski.com

CHROMIUM 1352. HEALTH EFFECTSsources: (1) sodium chromate; (2) calcium chromate; (3) soil containing chromium (30% chromium(VI),70% chromium(III)); or (4) a mixture of calcium chromate and the contaminated soil. The highest levelsof chromium were found in liver, spleen, kidney, lung, blood, brain, and testes after dosing with sodiumchromate, but the relative levels in these tissues after the other treatments followed no consistent pattern.Rats gavaged for 14 days with 13.9 mg chromium/kg/day from the four different sources had higherlevels of chromium in the tissues after they were dosed with the contaminated soil or the mixture ofcalcium chromate and the contaminated soil than with either of the chromate salts alone. Thus, therelative organ distribution of chromium depends on the source of chromium (Witmer et al. 1989, 1991).Components in soil may affect the oxidation state and the binding of chromium to soil components, andpH of the soil may also affect the bioavailability from soil.The chromium content in major organs of mice receiving drinking water that provided doses of 4.8, 6.1,or 12.3 mg chromium(III)/kg/day as chromium trichloride or 4.4, 5.0, or 14.2 mg chromium(VI)/kg/dayas potassium dichromate was determined after 1 year of exposure. Chromium was detected only in theliver in the chromium(III)-treated mice. Mice treated with chromium(VI) compounds had accumulationin all organs, with the highest levels reported in liver and spleen. Liver accumulation of chromium was40–90 times higher in the chromium(VI)-treated group than in the chromium(III)-treated group(Maruyama 1982). Chromium levels in tissue were 9 times higher in rats given chromium(VI) aspotassium chromate in drinking water for 1 year than in rats given the same concentration ofchromium(III) as chromium trichloride (MacKenzie et al. 1958). In rats exposed to potassium chromatein the drinking water for three or six weeks, a general trend of increasing chromium concentration withtime of exposure was apparent in the liver and kidneys, but only the kidneys showed a difference in theconcentration after exposure to 100 and 200 ppm. Blood concentrations were almost saturated by3 weeks with little further accumulation by 6 weeks. No chromium was detected in the lungs afterdrinking water exposure (Coogan et al. 1991a). After acute oral dosing with radiolabeled chromiumtrichloride (1 µCi for immature rats, 10 µCi for adults), adult and neonatal rats accumulated higher levelsof chromium in the kidneys than in the liver. At 7 days after dosing, the liver and kidney contained0.05% and 0.12% of the dose, respectively, in the neonates and 0.002 and 0.003% of the dose,respectively, in the adult rats. The carcass contained 0.95% of the dose in the neonates and 0.07% of thedose in adult rats. The lungs contained 0.0088% of the dose in neonates and 0.0003% of the dose in adultrats. No chromium(III) was detected in the skeleton or muscle. Approximately 35 and 0.2% of theadministered dose of chromium(III) at day 7 was retained in the gut of neonates and adults, respectively(Sullivan et al. 1984).