Kinetics of elimination of mesitylene and 3,5-dimethylbenzoic acid after experimental human exposure.

The possibility of evaluating occupational exposure to mesitylene based on the determination of unchanged solvent in capillary blood or 3,5-dimethylbenzoic acid in urine was investigated. The volunteers were exposed to mesitylene in a toxicological chamber (range 10-150 mg/m3). Concentrations of solvent or its metabolite in biological material were determined by gas chromatography. The toxicokinetic data concerning retention in the lung, absorption and elimination of mesitylene and its metabolite in biological fluids were obtained. The highest correlation coefficient value was obtained for the relationship between the absorbed dose of mesitylene and the excretion rate of 3,5-dimethylbenzoic acid in urine (r = 0.95). The biological indices of exposure for mesitylene have been proposed, taking the maximum allowable concentration (MAC) value in Poland (100 mg/m3) as the basis.