We presented here for the first time that human cytochrome P450 2E1, followed by 2A6, 2C6, 3A4 and 2D6 were the most efficient enzymes to oxidize 2-NP. The present study shows the similarity between human and rat hepatic enzymes metabolizing 2-NP to 2,5-DNB and indicate that rat might serve as a suitable model to mimic the fate of 2-NP in human.