Figure 2.
The Suggested Metabolic Pathway for 1- Methylpyrene (1-MP). 1-MP is first metabolized to 1-Hydroxymethypyrene (1-HMP) by CYP450 enzymes. The Majority (~80%) of 1-HMP is detoxified by alcohol dehydrogenase (ADH1B) to 1-Formylpyrene (1-FP) and then to 1-Pyrenyl carboxylic acid (1-PCA) by aldehyde dehydrogenase (ALDH). 1-PCA and its glucoronic acid conjugates are excreted in urine. Some of (~20%) 1-HMP is transformed to 1-Sulfooxymethylpyrene (1-SMP) of which the majority form DNA- adducts and tiny of it (~2%) detoxified by nucleophile glutathione and form Methylpyrenyl mercapturic acid (MPMA).