Cumene (CAS No. 98-82-8) was evaluated for subchronic toxicity. The test substance was administered by inhalation to rats (10/sex/group) 6 hours/day, 5 days/week at 0, 250, 750, 1,500, and 2,000 ppm for 1-2 days. At this time, it was determined that there was excessive toxicity (ataxia, abnormal respiration, ocular discharge, decreased motor activity, and collapse) in the highest exposure groups, and the concentrations were changed to 0, 250, 500, 1,000 and 1,200 ppm for the remainder of the 2- week study duration. As compared to controls, both sexes of rats in the 2,000/1,200 and 1,500/1,000 ppm groups had ataxia, ocular and anogenital discharge, hypo and/or hyperactivity, anemia, decreased food consumption and body weights, increased liver weights; females of these groups had increased serum chemistry levels (cholesterol, protein, albumin, and triglycerides) and adrenal weights, and males had increased kidney weights. Increased liver weights and ocular and anogenital discharges in males and females, increased kidney weights in males, and decreased food consumption in females were noted in the 750/500 group as compared to controls. The NOEL in this study was 250 ppm.