Enantioselective disposition and metabolic products of isofenphos-methyl in rats and the hepatotoxic effects

[Display omitted] •ICPO could be accumulated in liver.•The enantioselective metabolism mechanism IFP in liver were clarified.•ICPO can be regarded as a candidate biomarker of IFP exposure in urine and blood.•S-IFP exposure possess higher hepatotoxic effects than the racemic IFP and R-IFP. Isofenphos-methyl (IFP), a chiral organophosphorus pesticide, is one of the main chemicals used to control underground insects and nematodes. Recently, the use of IFP on vegetables and fruits has been prohibited due to its high toxicity. In this study, we investigated the enantioselective distribution and metabolism of IFP and its metabolites, namely, isofenphos-methyl oxon (IFPO) and isocarbophos oxon (ICPO), in male Sprague Dawley (SD) rats. Forty eight hours (48 h) after exposure, ICPO was the main detectable compound in blood (up to 75%) and urine (up to 77%), and we found that (S)-ICPO was significantly more stable than (R)-ICPO (p