Tissue distribution and excretion of tritiated tetrachlorodibenzo-p-dioxin in non-human primates and rats

Abstract Tritiated 2,3,7,8-tetrachlorodibenzo- p -dioxin (TCDD) was given to adult and infant rhesus monkeys and to rats to determine the distribution of this compound and to compare the tissue localization of the compound in the two species. Excretion, both daily and total, was similar in all three groups of animals, as was total tritium recovery. However, the concentration and total level of tritium in most tissues differed significantly between species. In the rat, retention in the liver accounted for over 40% of the administered dose, while this level was less than 10% in the livers of the monkeys. In contrast, a large percentage of the dose was located in the monkey in tissues with a high lipid content, particularly the skin, muscle and fat. In the rat, these tissues had much lower levels of TCDD.