Biochemical studies on phthalic esters I. Elimination, distribution and metabolism of di-(2-ethylhexyl)phthalate in rats.

Elimination, distribution and metabolism of di-(2-ethylhexyl)phthalate (DEHP) were studied in the rat by the tracer technique. About 80% of the dose was excreted in the urine and faeces in 5 to 7 days following intravenous or oral administration. Excretion in the urine was generally slightly greater than that in the faeces. After intravenous administration of [14C] DEHP the radioactivity was preferentially localized in the liver for a short period. Delayed excretion of DEHP was observed in particular in adipose tissue. After oral dosing no significant retention was found in organs and tissues. Radioactivity measurements showed that affinity was lowest for testicles and brain regardless of whether [14C] DEHP was administered orally or intravenously. Orally ingested DEHP was excreted unchanged in the faeces and four major metabolites were detected in the urine.