Four-week toxicity study of 4-methoxytoluene in rats.

4-Methoxytoluene was given by gavage to 4 groups of 20 rats at dosage levels of 0, 40, 120 or 240 mg kg-1 body weight/day for 4 weeks. There was a statistically significant decrease in serum creatinine and urea in the intermediate and high dose group for both sexes. Among males, a statistically significant decrease in the packed cell volume was observed in the high and intermediate dose group. A no-observed-effect level of 40 mg kg-1 body weight/day was determined.