P-32 POSTLABELING DETECTION OF AROMATIC ADDUCTS IN THE WHITE BLOOD-CELL DNA OF NONSMOKING POLICE OFFICERS

Atmosphere in urban areas may be polluted by a number of combustion so urces, including industries, vehicle traffic, and residential heating, Traffic police constitute a group of workers that is highly exposed t o urban pollutants, especially those from motor vehicle exhaust, We co nducted a biomonitoring study to simultaneously measure in 34 nonsmoki ng police officers and in 36 nonsmoking office workers, as referents, the individual benzo(a)pyrene [B(a)P] exposure using personal samplers and the formation of DNA adducts in peripheral WBCs using P-32-postla beling techniques. Our results show that the police officers were expo sed to significantly higher levels of B(a)P than were referents (P < 0 .0001), No seasonal variation of the atmospheric levels of B(a)P was f ound throughout the year, The median relative adduct labeling x 10(-8) values of the controls and exposed police officers were 0.94 (range, 0.1-3.7) and 1.3 (range, 0.1-5.5), respectively, using the nuclease P1 technique, Although the DNA adduct levels of police officers were glo bally higher than those of referents (P < 0.05), the difference was en tirely due to the summer difference [median values 0.80 (range, 0.1-1. 8) and 2.8 (range, 0.7-5.5), respectively (P < 0.001)], In winter, the DNA adduct levels were substantially identical, and in midseason, the re was only a very small increase in police officers, with respect to controls (statistically not significant), Moreover, a more significant seasonal variation of bulky aromatic DNA adduct levels was observed i n WBC DNA samples of police officers (P < 0.05) compared to those of r eferents, The seasonal variation of bulky aromatic adduct levels could be correlated with the reported seasonal variation of aryl hydrocarbo n hydroxylase inducibility in human lymphocytes.