Dimethoxyethyl phthalate: embryopathy, teratogenicity, fetal metabolism and the role of zinc in the rat.

A single intraperitoneal injection (0.6 ml/kg) of dimethoxyethyl phthalate (DMEP) was given to groups of Wistar strain rats on day 10, 11, 12, 13 or 14 of gestation. Control rats received 0.6 ml/kg of physiological saline intraperitoneally. In phthalate-treated rats, embryopathy was manifested by a high incidence (12-79%) of fetal deaths and fetal resorptions. Fetotoxic effects were expressed by a significant reduction in fetal weights. Hydrocephalus interna, a congenital malformation of the brain, was caused by DMEP. Congenital skeletal deformities (66-96%), with multiple skeletal (14-64%) and appendicular malformations (25-57%), were also induced by DMEP. Control rats exhibited no congenital malformations of the brain and no appendicular or multiple skeletal deformities. DMEP caused a significant decrease in the zinc content of the fetus. Fetoplacental metabolism 1 and 4 hr after intravenous administration of 14C-DMEP suggested rapid transfer of the parent compound to the fetus across the placenta and that DMEP is a teratogenic moiety. The possible role of zinc in phthalate-induced teratogenesis in rats is also discussed.