Propasol B (CAS No. 5131-66-8) was evaluated for subchronic toxicity. The test substance was administered dermally at exposure levels of 0.1, 0.3, or 1.0 ml/kg/day to rats (10/sex/group) one time/day, 5 days/week for 13 weeks. Skin reactions of treated rats included erythema, edema, and scales. No adverse effects were noted after ophthalmoscopic examination. There were no treatment-related changes in body weight, food consumption, urinalysis, hematology, clinical chemistry, or gross pathology. Females of the high-dose group had slightly increased relative heart weights and females in all treatment groups had a higher incidence of crust formation and epidermal necrosis of the skin. It was determined that none of the observed effects were of toxicological significant and that the no-toxic-effect level for this study is 1.0 ml/kg/day.