This letter is to inform you of the results of a pre-1977 (1975) acute inhalation study that recently came to our attention, on the above referenced test substance. The test substance was administered by inhalation (whole body exposure) to groups of 6 male Ch-R CD rats per concentration for approximately 4 hours, followed by a 14-day observation period. The exposure concentrations were 628, 1841, 7116, or 19,300 ppm (nominal). Rats were monitored for body weight changes and clinical signs of toxicity. No animals died and there were no reductions in body weight gain. Rats exposed to all concentrations showed signs of lethargy. Rats exposed to 19,300 ppm also demonstrated temporary prostration and a loss of righting when attempting to walk. These clinical signs were observed during exposure and rats appeared normal when removed from the exposure chamber. Under these experimental conditions, the clinical signs described above are being reported in accordance with the guidance given in the EPA TSCA Section 8(e) Reporting Guide (June 1991).