1-Hydroxypyrene glucuronide as the major aqueous pyrene metabolite in tissue and gut fluid from the marine deposit-feeding polychaete Nereis diversicolor.

Both 1-hydroxypyrene and 1-hydroxypyrene glucuronide are identified as the primary phase I and phase II metabolites of the four-ringed polycyclic aromatic hydrocarbon (PAH) pyrene in the marine deposit-feeding polychaete Nereis diversicolor. Identification of pyrene and primary metabolites was performed using high-pressure liquid chromatography (HPLC) with diode-array detection and fluorescence detection (HPLC/DAD/F) and an ion-trap mass spectrometer for positive identification of 1-hydroxypyrene glucuronide. Besides 1-hydroxypyrene and 1-hydroxypyrene glucuronide, the HPLC/F trace of tissue samples from pyrene-exposed worms showed three additional low-intensity peaks that may be related to pyrene metabolism based on similar excitation/emission wavelengths. The peaks were all too low in intensity to be positively identified. Of the total PAH in tissue, 1-hydroxypyrene glucuronide, 1-hydroxypyrene, and pyrene constituted 73%, 2%, and 25% respectively. Gut elimination of metabolic products is supported by the identification of 1-hydroxypyrene and 1-hydroxypyrene glucuronide in both gut fluid and defecation water. Being the only phase I metabolite of pyrene, 1-hydroxypyrene becomes a useful marker for PAH exposure, and it may serve as a valuable model compound for assessing species-specific PAH metabolic capabilities.