A 13-week and a 2-year feeding study were conducted in Fischer 344/DuCrj rats to evaluate the oral toxicity and carcinogenicity of S-570, a mixture of mono-, di-, tri-, and higher esters of sucrose with fatty acids derived from edible fats and oils. In both studies, S-570 was fed at 0, 1, 3, or 5% (w/w) of the diet to groups of 20 male and 20 female rats in the 13-week study and 50 male and 50 female rats in the carcinogenicity study. Animals in satellite groups of 14 rats/sex/group were sacrificed at 12 months to evaluate chronic toxicity. There were no S-570-related effects on survival, tumor incidence or time to tumor, ophthalmology, hematology, clinical chemistry, organ weights, or histopathology. These results indicate that S-570 is not toxic or carcinogenic when fed to rats at up to 5% of the diet for 2 years.