Prenatal interactions between ethanol and the industrial solvent 2-ethoxyethanol in rats: maternal and behavioral teratogenic effects.

Behavioral and neurochemical deviations in the offspring of rats exposed to 100 ppm ethoxyethanol during gestation have been reported previously. Since this compound is likely metabolized in the same manner as ethanol, the present study investigated the interactive effects of ethanol and ethoxyethanol on prenatal development. Groups of 15-20 pregnant Sprague-Dawley rats were given 10% ethanol in the drinking water with or without concomitant inhalation exposure to 100 ppm ethoxyethanol during gestation days 7-13 or 14-20. Another group was exposed to 200 ppm ethoxyethanol on gestation days 7-13, and sham-exposed controls were included for both gestation periods. Ethanol alone on days 14-20 and 200 ppm ethoxyethanol reduced overall weight gain during pregnancy. As in the previous research, pregnancy duration was extended in the groups given ethoxyethanol, but not in groups given ethanol alone. Neuromotor ability, as assessed by an ascent test and by a rotorod, was reduced by 200 ppm ethoxyethanol and by ethanol alone on gestation days 7-13. The group given ethanol plus ethoxyethanol on days 14-20 spent significantly longer in the start area of an open field, and this group as well as that given 200 ppm ethoxyethanol were less active than controls in the open field and in the shuttle box. When compared with previous research, it appears that ethanol early in gestation may reduce the effects, but later in gestation may enhance the effects of prenatal ethoxyethanol.