Identification of 1-hydroxypyrene as a major metabolite of pyrene in pig urine.

1-Hydroxypyrene is a major metabolite of pyrene given orally to pigs. A method for isolating the metabolite from urine is described, utilizing C18-adsorbent cartridges, h.p.l.c. separation, and fluorescence detection. Unconjugated 1-hydroxypyrene can be detected in the urine of pigs following oral administration of as little as 1 mg pyrene. Identity of the 1-hydroxypyrene was confirmed by u.v.-absorption and fluorescence spectrometry, mass spectrometry, and by comparison with the retention time characteristic of synthetic 1-hydroxypyrene.