Abstract 3609: The impact of household smoky coal and 5-methylchrysene exposures on oxidative damage

Abstract Background: Household air pollution (HAP) is a significant global health burden. In Xuanwei, China, never-smoking women experience the highest lung cancer rates worldwide, primarily due to the domestic use of smoky (bituminous) coal for heating and cooking. Our previous studies in this region identified methylated polycyclic aromatic hydrocarbons (PAHs), particularly 5-methylchrysene (5-MC), as potential significant contributors to lung cancer risk. 8-oxoguanosine (8-oxoGsn), a product of oxidative damage to RNA, has been reported a marker of oxidative damage in the body. Here, we examined whether the exposure to smoky coal and 5-MC are related to 8-oxoGsn. Methods: We conducted our analyses in an exposure assessment study in Xuanwei, China, which included 160 never-smoking women, out of which 43 had a repeated measurement. Information on the history of fuel usage was collected using an administered questionnaire. The 5-MC exposures were predicted with validated exposure models. We quantified plasma 8-oxoGsn levels using the Cayman DNA/RNA Oxidative Damage ELISA Kit. Generalized estimating equations (GEE) models were used to analyze the association between coal or 5-MC exposures and 8-oxoGsn levels, accounting for repeated measurements. Models were adjusted for age, body mass index (BMI), and other potential confounders. Results: The current, ever, and lifetime use of smoky coal were associated with increased 8-oxoGsn levels (pg/ml) compared to non-smoky coal use [Mean(SD): 6562(1755) vs. 6106(1269), p=0.021; 6551(1677) vs. 5948(1174), p=0.0023; 6590(1784) vs. 6236(1437), p=0.0082, respectively). Exposure to 5-MC (ng/m3-year) in adulthood was significantly associated with higher 8-oxoGsn levels (pg/ml) [Mean(SD): 5784(970), 6412(1534), 6789(1826) in increasing tertiles of 5-MC, p for trend=0.037]. Conclusion: Our findings suggest that exposure to smoky coal and 5-MC may elevate levels of 8-oxoGsn, formed through oxidative stress, reactive oxygen species production, and nucleic acid damage, which are critical pathways in the pathogenesis of cancer. Citation Format: Wei Hu, Jason Yy Wong, Batel Blechter, Lützen Portengen, George S. Downward, Yongliang Zhang, Mohammad Rahman, Bryan Bassig, Jun Xu, Jihua Li, Dean H. Hosgood, Lauren Hurwitz, Nathaniel Rothman, Roel C. Vermeulen, Qing Lan. The impact of household smoky coal and 5-methylchrysene exposures on oxidative damage [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 3609.