[Use of biological monitoring for evaluating occupational exposure in the paint and varnish industry].

Multi-component solvent mixtures are used in the painting and varnishing industry. Trimethylbenzene (TMB approximately 50%) is a main component of these mixtures. Assessment of occupational exxposureto TMB and xylene based on the biological exposure index (capillary blood, urine) was the aim of the study. Gas chromatography with headspace technique (HP 5890/FID) was used to determine unchanged compounds in capillary blood. Gas chromatography (Chrom 5/FID; HP 5890 Series II/FID) was also employed to determine methyl- and dimethylbenzoic acid in urine. The results of the study showed that high exposure to solvents was predominant in the Automative Products Department. The TMB and xylene concentrations in capillary blood accounted for about 120 and 340 micrograms/dm3, respectively, while metabolite levels in urine were 0.65 mg/h and 90 mg/dm3 (the latter value was corrected to specific gravity d = 1.016 g/cm3). The results were remarkably below the proposed values of the biological exposure limit and suggested that the level of occupational exposure was below during the study period. The exposure index used in our study proved to be very sensitive and can be recommended as a monitoring mode to assess exposure to a single solvent or mixtures of solvents.