INTRODUCTION The objective of this study was to determine the toxicity of a petroleum derived hydrocarbon@ API 81-15@ when administered to rats over a 13-week period by dermal application. Dosing was initiated on July 2@ 1984 (Day 1 of study). Due to mortality and the moribund condition of the animals and at the sponsor's request@ the 400 mg/kg group was terminated on July 26@ 1984 (Week 4) and the control@ 40 mg/kg and 200 mg/kg groups were terminated on September 21@ 1984 (Week 12).