Comparative effects of diethylhexyl phthalate or monoethylhexyl phthalate on male mouse and rat reproductive organs

Sexually mature mice injected (ip or sc) with doses ranging from 1 to 100 mg/kg monoethylhexyl phthalate (MEHP) or 50 to 100 mg/kg diethylhexyl phthalate failed to exhibit any significant alterations in testicular weight or zinc levels. Further, no changes in mouse seminal vesicle or anterior prostate weight and zinc levels occurred. Rats injected with MEHP (50 mg/kg) showed a 37% decrease in prostatic zinc; DEHP (100 mg/kg) caused a 33% decrease in prostatic zinc and a 31% decrease in gonadal zinc. These studies indicated that the reproductive system of the male rat is more sensitive to phthalate-induced toxicities than the mouse. Finally, phthalate acid ester-induced gonadal zinc depletion was evident despite the fact that the MEHP or DEHP was administered ip or sc, thus apparently eliminating altered intestinal absorption as the cause for the species differences.