Triclocarban

Blood levels after parenteral injection are low and comparison of the radioactivity and chemical determinations suggest rapid metabolism of the Triclocarban ^L2685. Human metabolism of TCC involves direct glucuronidation to form N- and N'- glucuronides as well as ring hydroxylation to 2'-hydroxy-TCC and 6-hydroxy-TCC, which are further metabolized to sulfate and glucuronide conjugates. In human subjects given a single oral dose of TCC, 27% of the dose was excreted in the urine within 80 hours. About 70% of the administered dose was excreted in the feces within 5 days ^L2685. The major urinary metabolites were N-glucuronides (average levels, 30 ng/mL) and a major plasma metabolite was the sulfate conjugate of 2'-OH-TCC (levels ranged from 0-20 ng/mL ^L2685. The maximum plasma level occurred 2.8 hr after dosing and was 3.7 nmol-equivalents of TCC per g of plasma (approximately 1.2 ppm). Biotransformation of TCC was rapid but did not appear to involve splitting of the basic TCC structure. The major plasma metabolites were N- and N'-glucuronides of TCC which were eliminated with half-life approximately 2 hr to the urine and 2'-hydroxy-TCC sulfate and 6-hydroxy-TCC sulfate (the o-hydroxy-TCC sulfates) which were removed with half life approximately 20 hr (presumably into the bile) ^L2685.

The metabolism of (14)C-TCC (3,4,4'-trichlorocarbanilide) has been investigated in humans following oral exposure to 2.2 mumol/kg. Fecal elimination (70% of dose) was complete at the 120 hour point after administration and the urinary excretion (27% of dose) was complete after 80 hours post-administration ^L2685. Urinary glucuronides appear to be valuable biomarkers of triclocarban exposure ^A32932.