[Studies on the teratogenic potential of 2,2'-isobutylidene-bis (4,6-dimethylphenol) in rats]

2,2'-Isobutylidene-bis(4,6-dimethylphenol), an antioxidant, was given orally to pregnant Wistar rats by stomach intubation at the dose levels of 5, 15 or 45 mg/kg body weight during days 7 to 17 of gestation, and the effects of the compound on dams and fetal developments were examined. In the dams at the two higher dose levels of 15 and 45 mg/kg, toxic signs (tremor, startle reflex, salivation, involuntary urination, wheezing and nostril discharge) were observed. Moreover, at the highest dose level, additional toxic signs (lacrimation and vaginal bleeding), suppression in maternal body weight gain and food consumption were observed. However, there was no evidence of an increase in malformations attributable to the treatment with 2,2'-isobutylidene-bis(4,6-dimethyl-phenol) in any of the treated groups. It was concluded that 2,2'-isobutylidene-bis(4,6-dimethylphenol) has no teratogenic effect in rats, though toxic signs were observed in treated dams of the 15 and 45 mg/kg groups.