Abstract

The objective of this study is to examine the correlation between the tolylene concentration in the work environment of organic solvents and the concentration of hippuric acid in urine of workers exposed toluene, and to acquire the fundamental materials of workers' health care and to assist the assessment of the biological permissible exposure limit. The control groups are 72 workers who had never been exposed to toluene and the case groups are 101 workers who had been exposed to toluene. This study was conducted to examine the correlation between the concentration of toluene in work environment and workers' hippuric acid concentration, to investigate the complaint difference of subjective symptoms by means of questionnaire, between the case groups and control groups. The results and conclusions are as follows: 1) The highest mean concentration of toluene in the air is 544.13+/-7.75 ppm in the Printing Department of mixing organic solvents. The concentrations of the others are 463.27+/-5.24 ppm in Department of mixture for organic solvents, and 393.56+/-45.69 ppm in the Printing Department(1), and 248.38+/-45.16 ppm in the Printing Department(2), and 159.38+/-18.51 ppm in the Printing Department(3). 2) The highest mean concentration of hippuric acid in urine is 6034.84+/-1298.35 mg/l in the Printing Department with mixing organic solvents. The concentrations of the others are 4798.44+/-784.53 mg/l in Department of mixture of organic solvents, and 2883.06+/-701.90 mg/l in the Printing Department(1), and 1449.98+/-905.19 mg/l in the Printing Department(2), and 598.52+/-299.43 mg/l in the Printing Department(3). 3) As the toluene concentration in the work environment becomes higher, the concentration of hippuric acid in urine also becomes higher. It is found that the coefficient of correlation between toluene concentration and the concentration of hippuric acid are positive (r=0.868, Y=7.18X+349.57). 4) It is found that the case groups complain of much more subjective symptoms than the control groups.