Microprobe X-ray Absorption Spectroscopic Determination of the Oxidation State of Intracellular Chromium following Exposure of V79 Chinese Hamster Lung Cells to Genotoxic Chromium Complexes

The oxidation state of intracellular chromium has been determined directly in mammalian lung cells exposed to mutagenic and carcinogenic chromium compounds. Microprobe X-ray absorption spectroscopy (XAS) experiments on single V79 Chinese hamster lung cells showed that Cr(VI) and Cr(V) complexes were reduced completely (>90%) to Cr(III) within 4 h of exposure of the cells. This result provides direct evidence for the hypothesis that these genotoxic oxidants react rapidly with intracellular reductants.