The study was designed to assess toxicity of the test substance following a single oral dose to the rat. The procedure used is described in this protocol. The procedure complies with that described in the EPA Health Effects Testing Guidelines, Subpart B - General Toxicity Testing 798.1175 Acute oral toxicity, September 27, 1985 (described in Federal Register Vol. 50, No. 188) and subsequent revisions. Subpart B provides detailed information relating to data requirements of 40 CFR Part 798 and supports the Toxic Substances Control Act (TSCA). A group of ten fasted rats (five male rats and five female rats) received an oral gavage dose of Dow , Corning AF Emulsion, Food Grade administered as supplied at a dose of 5000 mg/kg bodyweight. All animals were killed as scheduled at study termination (Day 15). Clinical signs of reaction to treatment were confined to piloerection (a sign when seen in isolation is considered to be indicative of disturbance of the animals normal behaviour as a result of the treatment procedure). Piloerection was first evident in all rats within ten minutes ofdosing and persistent thereafter throughout Day 1. No other signs of reaction to treatment were observed and all animals had fully recovered from treatment by Day 2. All rats were considered to have achieved satisfactory bodyweight gains throughout the study. Macroscopic pathology revealed no abnormalities. Under the conditions of this study, the acute lethal oral dose to rats of Dow Corning AF Emulsion, Food Grade was demonstrated to be greater than 5000 mg/kg bodyweight.