The Nutritional Supplement Chromium(III) Tris(picolinate) Cleaves DNA

Chromium(III) tris(picolinate) [Cr(pic)3] is currently a very popular nutritional supplement; however, its safety has recently been questioned, especially with regard to its ability to act as a clastogen. At physiologically relevant concentrations, Cr(pic)3 is reduced by biological reductants, including ascorbate and thiols, to Cr(II)-containing species. These species are susceptible to air oxidation, resulting in the catalytic generation of the potent DNA-damaging agent hydroxyl radical. In the absence of reductants, H2O2 can interact with Cr(pic)3 to produce hydroxyl radicals by a second, less efficient mechanism. Cr(pic)3 is extremely stable, which allows the complex to be readily absorbed but also to potentially be incorporated into cells intact. In this form, Cr(pic)3 is primed by its redox potential to enter into the generation of hydroxyl radicals. This study suggests that investigation of the long-term effects of supplementation of the diet with Cr(pic)3 are needed to assess the safety of this material.