The report penains to C-11 Ketone Solvent, a mixture of Sundecanone (CAS No. 927-49-1), 5-ethyl-2-nonanone (CAS No. 5440-89-1), 2-hexanone (CAS No. 591-78-45), 5-methyl-2-hexanone (CAS No. 110-12-3), and various cyclic and acyclic aliphatic ketones, and is being submitted because of effects observed in a study conducted by multiple routes of exposure. The title of the study being submitted is 'Basic Toxicity of C-11 Ketone Solvent'. The report is being identified as a study involving other than human effects (Unit H.B.2.b of CAP Agreement). Groups of five male rats and five female rats were administered 2-24 doses of the test material by gavage at 4000, 2000, 1000, 500, 250 or 125 mg/kg over 3-18 days. Additional groups of male rats were treated at 125, 625 or 31 mg/kg. Males and females in the high-dose group were euthanatized after three doses due to poor condition. Abnormalities in the 2000 and 1000 ag/kg dose groups included decreases in feed intake and body weight gain (2000 ag/kg dose group females only), and changes in organ weights. At the 4000, 2000, and 1000 mg/kg dose levels, gross and histopathologic changes were seen in both males and females and involved a number of organs. Additional effects are discussed in the addendum to the toxicity report. Except for minimal to minor hyaline droplet degeneration of the kidneys, there were no gross or histopathologic changes in 500, 250 or 125 mg/kg dose group males. No treatment-related effects were observed in the 62.5 or 31 mg/kg dose group males or in the 500, 250 or 125 ag/kg dose group females.