Tissue distribution, excretion, and metabolism of 1,2,7,8-tetrachlorodibenzo-p-dioxin in the rat.
A tissue distribution, excretion, and metabolism study was conducted using a relatively non-toxic dioxin congener, i.e., 1,2,7,8-tetrachlorodibenzo-p-dioxin (1278-TCDD), to gain a better understanding of mammalian metabolism of dioxins. Conventional, bile duct cannulated, and germ free male rats were administered mg/kg quantities as a single oral dose. Elimination of 1278-TCDD was largely complete by 72 h. Distribution of [14C]1278-TCDD was low in all tissues examined. Metabolites were identified in urine, bile, and feces by negative ion FAB-MS and 1H-NMR, or GC/MS. The major fecal metabolite was a NIH-shifted hydroxylated TCDD. The bile contained a glucuronide conjugate of this hydroxy TCDD, and a diglucuronide conjugate of a dihydroxy-triCDD. The major metabolites in urine were glucuronide and sulfate conjugates of 4,5-dichlorocatechol.
USDA Biosciences Research Laboratory, University Station, Fargo, ND 58105, USA. hakkh@fargo.ars.usda.gov
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D000818:Animals; D001711:Biotransformation; D004785:Environmental Pollutants / Q000378:metabolism / Q000493:pharmacokinetics*; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D000072317:Polychlorinated Dibenzodioxins / Q000031:analogs & derivatives / Q000378:metabolism / Q000493:pharmacokinetics*; D051381:Rats; D017207:Rats, Sprague-Dawley
D004785:Environmental Pollutants; D000072317:Polychlorinated Dibenzodioxins