Urinary excretion of hippuric acid as a biological parameter of exposure to toluene
Kuo, T.L.; Fong, J.M.; How, S.W.
Journal of the Formosan Medical Association 79(8): 686-693
1980
ISSN/ISBN: 0371-7682 PMID: 6934256 Document Number: 158412
Urinary excretion of hippuric acid, a biological metabolite of toluene, was studied in workers with exposure and non-exposure to toluene. Mean values were 653 (.+-. SD = 283) mg/l (n = 23) and 165.8 (.+-. SD = 87.5) mg/l (n = 24), respectively. Data showed statistically significant differences. Urine of 23 subjects with occupational exposure to toluene was analyzed by colorimetric methods and by Ohmori's method. There was a high correlation between values of hippuric acid measured by these 2 methods (r = 0.962, P < 0.005). Comparing hippuric acid and hippuric acid/creatinine values, it was found that the latter were less variable. Linear regression line between hippuric acid and creatinine was observed with a positive correlation (r = 0.727 and 0.767) for each group (P < 0.01). Use of hippuric acid/creatinine value in spot urine sample as a biological parameter of the degree of exposure to toluene may be valuable.