Toxic Potential of the Plasticizer Di(2-ethylhexyl) Phthalate in the Context of Its Disposition and Metabolism in Primates and Man

Although human toxicity from exposure to the plasticizer di(2-ethylhexyl) phthalate (DEHP) is unknown, reports of animal toxicity from DEHP have stimulated extensive toxicological studies. In the absence of direct toxicity data, information on the disposition and metabolism of DEHP in primates and man may enhance our assessment of the toxic potential of DEHP in man. Studies of DEHP disposition and metabolism in the African Green monkey and man show that the compound is rapidly and extensively metabolized. It is excreted largely in the urine (> 90%) as conjugated (glucuronide) oxidation products of mono(2-ethylhexyl) phthalate; excretion in feces accounts for the other 10% of the administered DEHP. Plasma disappearance of parenterally administered DEHP is equally rapid so that by 24 hr following DEHP administration, plasma DEHP concentrations are virtually undetectable, while greater than 70% of the dose has been excreted in urine and stool. The transience of DEHP in primates and the extent to which it is metabolized and conjugated may play a role in the observed lack of toxicity.