A 90-day inhalation study was conducted in Sprague-Dawley rats, Fischer 344 rats and B6C3F1 mice to determine the subchronic toxicity of carbon disulfide (CS2) vapors using an exposure regimen of 6 hours per day, 5 days per week for at least 89 consecutive days. This addendum report contains data pertaining to Sprague-Dawley rats. The study was performed at ToxiGenics, Inc., 1800 East Pershing Road, Decatur, IL 62526 under the sponsorship of the Chemical Industry Institute of Toxicology, Research Triangle Park, NC 27709. The study began on February 3, 1982 and was completed on May 12, 1982. CIIT issued the original report as CIIT Docket No. 62063 on February 25, 1983, and it was amended April 26, 1983. The final report was received at CIIT on July 20, 1983. All teased nerve fiber slides were received at CIIT on June 24, 1983. Slides of Epon-embedded tissue were shipped directly to Dr. D. Graham on August 8, 1983 and returned to CIIT on March 25, 1992.