Toxicology

Of all of the carcinogens, chromium (Cr) has the highest occupational exposure to workers and is of growing environmental concern. While Cr(VI) is the carcinogenic form of Cr, it does not interact with DNA in the absence of cellular reductants. X-ray absorption spectroscopy is being used to characterize for the first time the structures of a range of reactive Cr(VI), Cr(V) and Cr(IV) complexes with biological reductants. many Cr(III) complexes, which are the ultimate products of the reductants, have also been characterized.

Using microfocus synchrotron radiation induced x-ray emission (Micro-SRIXE), researchers at the University of Sydney and ANSTO have been able to follow the uptake of Cr(III) and Cr(VI) chemical species into individual cells with sub-micron resolution.