Toluene in venous blood during and after work in rotogravure printing

Abstract
Toluene exposure was studied in 62 male rotogravure printers, employed in three plants. The exposure level as measured by personal sampling during a week ranged from 8 to 1080 mg/m3 (median 96). The concentration of toluene in venous blood sampled directly after work correlated significantly with the time-weighted average (TWA) for toluene in air during the preceding workshift (n = 57, Spearman's r = 0.84, P < 0.00001). The post-shift toluene level in venous blood is usable for biological monitoring of exposure. An air level of 100 mg/m3 corresponds to an average blood toluene level of 2.9 μmol/l; an air level of 300 mg/m3 to 8.2 μmol/l. The elimination of toluene is slow. Thus, toluene was detected in most Monday pre-shift blood samples and the levels increased statistically significantly during the work week (median 0.21 versus 0.42 μmol/l, P < 0.0001). The toluene level in venous blood sampled directly before work on Thursday/Friday was found to be a function of the estimated mean exposure during the work week. In a multiple linear regression analysis, the mean exposure during the week was a good predictor for the concentration of toluene in venous blood before work at the end of the week (n = 52, r = 0.71). Thus, pre-shift blood values at the end of the week can be used as a biological index for the weekly exposure, when the variation of the ambient toluene concentration is known. The slow decrease of toluene in venous blood was followed in six workers for two weeks after cessation of exposure. Two of them still had detectable amounts of toluene in blood after 13 d (detection limit = 0.01 μmol/l).

This publication has 11 references indexed in Scilit: