Diethylstilbestrol: evidence for metabolic activation in man, rat, and hamster.

Oxidative biotransformation of radioactively and deuterium-labeled DES gives rise to several metabolites in intact Wistar rats, Syrian golden hamsters, and humans. With the use of radio gas chromatography and gas chromatography--mass spectrometry, the major urinary and biliary metabolites were tentatively identified as hydroxy and methoxy derivatives of DES and dienestrol, of which the relative amounts excreted depended largely on the species. Some of the metabolites are potentially reactive substances or have reactive metabolic precursors such as epoxides or allylic hydroxy compounds that might be associated with the adverse effects of DES.