Chromium(III)-containing products were isolated from the reduction of chromate using molecules possessing the thiol function, i.e. L-cysteine, L-cysteine-ethyl ester and mercaptopropanediol. The products were characterized by various analytical, spectroscopic, magnetic and electrochemical studies. The in vitro interaction of these products with pUC18DNA has shown alterations in the DNA structure as established using agarose gel electrophoresis.