Acute oral toxicity was evaluated in groups of 5 male and 5 female fasted Sprague-Dawley rats administered 4-chlorotoluene by gavage at a level of 1.7, 2.3, 3.3 or 4.6 g/kg. Mortality was observed in 2 males in the 1.7 g/kg group, 3 males and 4 females in the 2.3 g/kg group, and in all 5 males and females in the 3.3 and 4.6 g/kg groups. The LD50 was determined to be 2.1 g/kg (1.8 - 2.4 g/kg). Clinical observations included a decrease in motor activity, tremors, cyanosis, piloerection, excess salivation, chromodacryorrhea, increase in respiratory rate, decrease in respiratory rate and lacrimation. Gross necropsy revealed brightred or red and mottled lungs, stomach and intestinal irritation and cream colored, white or dark fluid in the stomach and intestine, red stained fur around the nose, 'blanched' stomachs and fluid filled stomachs.