Abstract 4696: Increased levels of urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG) and 1-hydroxypyrene (1-OHPyr) after 6 hours of work among roofers in South Florida

Abstract

Abstract Background: Occupational exposures to asphalt have been linked to increased risks of lung, bladder, stomach, skin, buccal cavity cancers, and leukemia among roofers. This study investigates the relationship between 1-OHPyr, a biomarker of polycyclic aromatic hydrocarbon (PAH) exposure, and 8-OHdG, a marker of oxidative DNA damage, before and after 6 h of work in roofers from South Florida. Methods: Nineteen roofers in the Miami-Dade area were recruited with informed consent. Urine samples were collected and questionnaires were applied before and after 6 h of roofing work. 1-OHPyr was analyzed via HPLC, creatinine was measured using the Colorimetric Detection Kit, cotinine was measured using the Cotinine Direct ELISA kit, and 8OHdG was analyzed by ELISA using the new 8-OHdG check kit. All statistical tests were performed after natural logarithmic transformation using the SAS system software. Results: Of the 19 roofers, 6 were Hispanics and 13 were African-Americans. All were male with an average age of 38.4. Nine of the roofers were smokers. While 52.6% of the population reported never consuming alcoholic beverages, 4 (21.1%) workers reported having 12-24 alcoholic drinks in one sitting and 7 (36.9%) workers reported consuming alcoholic drinks on at least 3 days of the week. Levels of 8-OHdG and 1-OHPyr were significantly higher in urine samples after the work when compared to samples obtained before the work (geometric mean levels before vs after work were 336.6 vs 632.7 pg/l for 1-OHPyr and 9.55 vs 37.3 ng/ml for 8-OHdG). Smokers had significantly higher levels of urinary 1-OHPyr than nonsmokers at both sampling times; but the difference was smaller after the work (2.61-fold vs 1.61-fold). Smokers had also higher levels of 8-OHdG when compared to nonsmokers at both times, but the difference was greater after the work (1.51-fold vs 1.67-fold). Urinary cotinine levels were significantly higher in smokers than nonsmokers (6.63-fold and 8.57-fold for before and after work, respectively); however, levels were not different before and after the work in both groups. There was no significant correlation between 1-OHPyr and 8-OHdG before the work; however, a strong and significant correlation was observed in samples obtained after the work (Pearson r = 0.833, p < 0.0001). Conclusion: Roofers in this pilot study were exposed to significant levels of PAHs during their work shift. This exposure was independent of their smoking habits, but it was significantly associated with oxidative DNA damage. Alcohol consumption appears to be a frequent habit in this worker population with some workers exhibiting heavy drinking patterns on a regular basis. While this group of roofers in South Florida experience increased DNA damage during their work, they also exhibit a high frequency of behavioral risk factors for cancer. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4696.