Hexachlorophene metabolism in rats: the hepatic route

The terminal elimination rate of radioactivity from the bile of bile-duct cannulated rats, that had received hexachlorophene-14C via the hepatic portal vein, had an apparent first-order half-life of about 10 hr. Tissue distribution studies in these rats indicated that 35-47% of the carbon-14 of the dose was eliminated through the bile within 24 hr. Significant amounts of radioactivity were also found in the liver and carcass at that time; the brain was the only tissue that did not consistently have much higher concentrations of carbon-14 than the blood. The rate limiting step in the disposition of hexachlorophene may be excretion into the bile. A bile-feeding technique demonstrated enterohepatic circulation.