Assessment of Household Air Pollution Exposure and Associated Health Effects from Burning Firewood and Yak Dung on the Eastern Tibetan Plateau

摘要

Background: Cooking and heating with solid fuels produces high levels of household air pollution (HAP) and is a substantial contributor to the disease burden. This study assesses the sources, magnitudes, and chemical compositions of HAP in traditional Eastern Tibetan Plateau households; examines the perturbation of urine metabolome in response to the HAP exposure; and explores how these correlate with cookstove use, fuel type, cooking behaviors, and residents' overall health. Methods: We measured 24-hour personal exposure to PM2.5 (n = 46) and kitchen area black carbon (BC) concentrations (n = 8), using MicroPEM and microAeth, respectively. We also measured particle-bound polycyclic aromatic hydrocarbon (PAH) (n = 12) and metal concentrations (n = 11) during post-analysis of the MicroPEM filter. We conducted household surveys (n = 24) regarding demographics, cookstove usage, fuel type, cooking behavior, and lifestyles. In addition, we collected fasting urine (n= 46) and applied untargeted metabolite profiling to monitor metabolic features and assess associations with measured HAP exposures. These data will be analyzed with bioinformatics approaches-Manhattan plot and Mummichog pathway analysis. Results: Our results reaffirm that burning firewood and yak dung, result in high PM2.5 and BC exposures. The geometric mean (95% CI) concentration was 92.2 (12.5, 682.4) μg/m3 for PM2.5 and the mean ± standard deviation (SD) concentration was 5.8 ± 5.5 μg/m3 for BC, 474.3 ± 584.3 ng/m3 for EPA standard suite of 16 PAHs, respectively. The mean ± SD of concentrations of twenty-five detected metal elements ranged from 0.9 ± 1.1 (Co) to 1585.1 ± 1621.5 ng/m3 (Si). Our statistical analyses illustrate high concentrations of PM2.5, BC, most PAHs and metals are significantly associated with village characteristics and household fuel types. Conclusion: Results from this study provide useful information for understanding the HAP exposure and related health risks in Tibetan communities.