Propylene dichloride (1,2- dichloropropane, CAS 78-87-5) was administered by gavage to groups of 10 Sprague-Dawley rats on gestation days 6 through 15 at dosages of 0, 50, 125, 250 and 500 mg/kg/day in order to evaluate maternal toxicity and embryolethal potential and set dose levels for a more definitive oral teratology study. Animals were sacrificed at gestation day 16 and necropsied. Dose-related toxic effects were noted at all treatment levels on day 1 of treatment in some of the battery of observational tests including decreased respiration, movement, muscle tone and extensor thrust reflex and increased salivation, lacrimation and perineal urine staining. However, there seemed to be accomodation to the effects so that only the highest two doses elicited any of these effects subsequently. The three highest dose groups showed decreased maternal weight gain and feed consumption on days 6-9 of gestation while the highest dose group also had decreased hematological values and continued to have a decreased body weight through day 16. While there were no obvious reproductive effects (numbers of implants, resorptions, litter size, fetal population composition) due to treatment, the clinical observations of maternal toxicity lead the authors to conclude that a future definitive oral teratology study should use dosages of 0, 10, 30 and 125 mg/kg body weight.