Hippuric acid, phenol, and trichloroacetic acid levels in the urine of Japanese subjects with no known exposure to organic solvents.

Ikeda, M., and Ohtsuji, H. (1969).Brit. J. industr. Med.,26, 162-164. Hippuric acid, phenol, and trichloroacetic acid levels in the urine of Japanese subjects with no known exposure to organic solvents. Urine samples from 36 male and 30 female university students and 31 male factory workers with no known exposure to industrial organic solvents were analysed for hippuric acid, phenol, and trichloroacetic acid, which are the major metabolites of toluene, benzene, and trichloroethylene respectively. The normal levels were less than 1·4 g./l. for hippuric acid, less than 80 mg./l. for phenol, and less than 1 mg./l. for trichloroacetic acid. No evidence was obtained to suggest that correction for urine concentration with either specific gravity or creatinine concentration minimizes individual variation of metabolite levels.