No abstract

In this study, 32 booth attendants (the exposure group) and 21 in pre-job training to become booth attendants (the reference group) were randomly selected from a highway toll station. Personal PAH samplings were conducted on the exposure group on each day during the studied workweek. Pre-shift urinary 1-hydroxylpyrene levels (1-OHP) were measured on the first day of the workweek (BM(pre)) for both the exposure and reference groups, but the post-shift 1-OHP levels were measured on the last day of the workweek (BM(pest)) only for the exposure group. For the exposure group, we found that their mean total PAH exposure level (C(total PAHs)) was 11 400 ng/m3 and that their mean BM(post) was significantly higher than their mean BM(pre) (= 3.02 and 0.910 micromol of 1-OHP/mol of creatinine, respectively). In addition, the mean BM(pre) for the exposure group were higher than that for the reference group (= 0.410 micromol of 1-OHP/mol of creatinine). The above results suggest that vehicle exhaust significantly affects the booth attendants' 1-OHP levels. None of the three personal factors (age, work experience, and smoking habit), except for C(total PAHs), had a significant effect on predicting booth attendants' BM(inc) levels (= BM(post) - BM(pre)) (R2 = 0.57). The above results suggest that urinary 1-OHP could be a suitable biomarker for characterizing workers' PAH exposures. Similarly, we found that none of the three personal characteristics, except for the involved vehicle flow rates and vehicle types, had a significant effect on predicting booth attendants' BM(inc), levels (R2 = 0.60). The above result suggests that the traffic densities of various traffic types could be a suitable surrogate indicator for assessing workers' PAH exposures. Considering that the type of traffic designed for a given type of tollbooth is quite similar all over the world, the results obtained from this study, at least, could be served as a stepping-stone for providing a cheaper and convenient way for assessing traffic PAH exposures in the future.