ETHNIC-DIFFERENCES IN BIOLOGICAL MONITORING OF SEVERAL ORGANIC-SOLVENTS .1. HUMAN EXPOSURE EXPERIMENT

Objectives: In order to improve the reliability of biological monitori ng and the development of biological limit values, ethnic differences for several organic solvents were studied in Orientals and Caucasians. Methods: Six Caucasian and six Oriental volunteers were exposed to ea ch organic solvent in an exposure chamber for 6h. Exposure concentrati on to each organic solvent studied was 50 ppm for perchloroethylene, 5 0ppm for styrene and 100ppm for m-xylene, respectively. Biological mon itoring was carried out for the parent organic solvents in exhaled air and in blood, and for the metabolites in urine during and after expos ure. Results: Caucasians showed higher concentrations of perchloroethy lene in exhaled air than Orientals after exposure. But Caucasians show ed lower concentrations of styrene in the exhaled air than Orientals d uring the second half of exposure and after it. Orientals showed lower concentrations of urinary metabolites than Caucasians except for mand elic acid. There were no statistically significant differences in the concentrations of solvent in blood for all three solvents. Conclusions : Implications of these differences in biological levels, under identi cal exposure conditions, are discussed in the context of biological mo nitoring.