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Chromium isotopes and the fate of hexavalent chromium in the environment

Andre S. Ellis·Thomas M. Johnson·Thomas D. Bullen
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Abstract

Measurements of chromium (Cr) stable-isotope fractionation in laboratory experiments and natural waters show that lighter isotopes reacted preferentially during Cr(VI) reduction by magnetite and sediments. The 53 Cr/ 52 Cr ratio of the product was 3.4 ± 0.1 per mil less than that of the reactant. 53 Cr/ 52 Cr shifts in water samples indicate the extent of reduction, a critical process that renders toxic Cr(VI) in the environment immobile and less toxic.

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Andre S. Ellis, Thomas M. Johnson, Thomas D. Bullen. 2002. Chromium isotopes and the fate of hexavalent chromium in the environment. https://doi.org/10.1126/science.1068368

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