OCCUPATIONAL CHRONIC EXPOSURE TO ORGANIC-SOLVENTS .7. METABOLISM OF TOLUENE IN MAN

A group of printing workers (n = 34) exposed to toluene was examined according to the concentrations of hippuric acid, phenol, o-cresol, and (m+p)-cresol in urine. The average concentration in the air of the workroom was 23 ppm. It is shown that, besides hippuric acid, small amounts {Mathematical expression} of o-cresol. which is not a normal constituent of urine, were formed from toluene. The occurrence of o-cresol could be proved by mass spectrometry. On account of the small amounts of benzene present in industrially used toluene-in this case 0.025%-the average concentration of phenol in urine of the exposed group was significantly higher statistically {Mathematical expression} than in urine from the controls {Mathematical expression}. © 1979 Springer-Verlag.