Mutagenicity and Disposition of Chromium

Hexavalent chromium was administered to rats at doses of 20-240 mumol kg-1 for several periods of time, from 2 to 14 days. Lung, liver and blood contained the highest amounts of chromium, as detected by atomic absorption or by ICP, 24 h after cessation of treatment. A maximum of 40% of the dose was recoverable in organs along with feces and urine at this same time period, and chromium in soil (5.6% Cr) was absorbed better than equimolar amounts of the hexavalent chromates of calcium or sodium. The contaminated chromium-containing soil was found to have 30-35% of the chromium in the hexavalent state. The mutagenicity of chromium as tested in the bacterial strain of Salmonella typhimurium (strain TA 104) was decreased when tested without metabolic activation with the addition of leachate (of inexact analysis) from a waste site. When studied by alkaline elution, chromium (5-20 microM) caused single strand breaks as well as DNA-protein crosslinks in A549 lung cells, while with L1210 mouse leukemia cells, only DNA-protein crosslinks were found. Chromium(III) compounds caused no damage to DNA.