Biological markers in PAH exposed workers and controls.

Workers employed in a graphite electrode producing plant (n = 16) and a coke oven (n = 33) were compared with a control population of maintenance workers in a blast furnace (n = 54). The following parameters were analyzed: concentration of 13 different PAHs in the work environment measured by personal air samplers, concentration of hydroxypyrene in the urine, smoking habits (via urinary thiocyanate levels and a questionnaire) and cytogenetic aberrations in lymphocytes (SCE, HFC and MN). On the basis of PAH levels in the work environment and hydroxypyrene concentrations in the urine, the workers from the graphite electrode producing plant were the most exposed. However, statistically significant differences in SCE and HFC and positive correlations between the cytogenetic markers and airborne PAH levels on the one hand, and urinary hydroxypyrene concentrations on the other hand were only detectable in the workers from the coke oven with a lower exposure. No statistically significant effect of smoking was observed. As to the inter-comparison of the different cytogenetic markers, one may consider that SCE and HFC are more sensitive than MN frequencies for the biomonitoring of exposure to PAHs. Whether MN or SCE are the best biomarker for risk assessment of cancer and whether the presence of PAHs in the work environment is really responsible for the cytogenetic effects found in this study could not be ascertained.