P-Chlorotoluene was administered by gavage for 14 and 90 days to male and female Sprague-Dawley-derived rats at dose levels of 200, 600 and 1800 mg/kg/day and 50, 200 and 800 mg/kg/day, respectively. In the 14-day study 8 of 10 animals of each sex in the high-dose group died due to treatment. Other treatment-related signs for these animals included an adverse effect upon body weight, and clinical signs of salivation, tremors and prostration. In the 200 and 600 mg/kg/day groups there were no apparent treatment-related effects. In the 90-day study, 4 of 10 males and 2 of 10 females in the high-dose group died due to treatment. Other signs for this treatment group included an adverse effect upon body weight, and clinical signs of languid behavior, prostration, tremors, sensitive to touch, epistaxis and respiratory distress. Increases in alkaline phosphatase and creatinine (males only), and increases in adrenal (absolute and relative, females), kidney (relative, both sexes) and liver (relative, both sexes) weights were also noted.