Developmental toxicity of di-isodecyl and di-isononyl phthalates in rats

The developmental toxicity of di-isodecyl phthalate (DIDP; CAS RN 68515-49- 1) and di-isononyl phthalate (DINP; CAS RN 68515-48-0) were investigated in Sprague-Dawley rats. DIDP and DINP were administered by gavage to mated ra ts at doses of 0, 100, 500, and 1000 mg/kg/d on Gestation Days (GD) 6 throu gh 15, Cesarean sections were performed on GD 21 and the fetuses removed fo r evaluation. Maternal weight gain and food consumption were significantly reduced at 1000 mg/kg/d during the exposure period. No treatment-related ef fects were noted at cesarean section, nor were there any fetal morphologic observations except for an increased frequency of seventh cervical and rudi mentary lumbar ribs at the maternally toxic exposure level of 1000 mg/kg/d. Under these study conditions, mild maternal and developmental effects were observed at 1000 mg/kg/d, Both maternal and developmental NOAELs were ther efore established at 500 mg/kg/d, The results indicate that neither DIDP no r DINP is teratogenic or a selective developmental toxicant, (C) 1999 Elsev ier Science Inc.