INTRODUCTION The objective of this study was to determine the toxicity of a selected petroleum-derived hydrocarbon@ API 85-01@ when administered to rabbits over a 4-week period by dermal application. Dosing was initiated on June 2@ 1986 and was completed on June 28@ 1986. All animals were terminated by injection of T-61R euthanasia solution. This study was run concurrently with a companion study reassessing an additional API compound. A pilot five-day dermal study in rabbits (Phase I) was performed in order to determine the dose levels to be used during this study (Phase II). Phase I dosing was initiated on April 28@ 1986 and terminal sacrifice occurred on May 9@ 1986. The report of Phase I results is presented in Addendum@ I of this report.