Abstract 3238: Annual coal use and stove improvement in relation to cause-specific mortality in a 36-year cohort analysis among anthracite coal users in Xuanwei, China

Abstract

Abstract Emissions from burning solid fuels contribute substantially to the global disease burden. Xuanwei (XW), China, has among the highest lung cancer rates in the world, which has been attributed to the use of bituminous (“smoky”) coal for cooking and heating. Anthracite (“smokeless”) coal is also used in XW and is considered a “cleaner” fuel source compared to bituminous coal, but it emits high-levels of certain indoor pollutants (e.g. nitrogen dioxide and sulfur dioxide) and the disease burden associated with its use has not been well characterized. To evaluate the impact of anthracite coal use and stove improvement on all- and cause-specific mortality, we conducted a cohort study in which 42,400 XW residents were followed from 1976-2011. We ascertained information on fuel use, stove improvement, and lifestyle factors using questionnaires, and mortality data were obtained from hospital records and death certificates. Sex-specific multivariable Cox regression models were used to estimate the hazard ratio (HR) of all- and cause-specific mortality in relation to time-dependent annual coal tonnage use (median: 2 tons/year; 25th and 75th percentile = 1 and 3 tons/year, respectively) and stove improvement among 4,486 lifetime anthracite coal users. Compared to subjects who used <2 tons of anthracite coal/year, higher annual tonnage was associated with increased total mortality (HR=1.16, 95% CI =1.03-1.30 in men; HR=1.18, 95% CI =1.02-1.37 in women), total respiratory disease mortality (HR=1.52, 95% CI =1.16-1.99 in men; HR=1.74, 95% CI=1.28-2.36 in women), which was driven by pneumonia, and total cancer mortality in men (HR=1.66, 95% CI=1.09-2.51) but not women. Lung cancer mortality was non-significantly increased and liver cancer mortality was significantly increased in both men and women for use of ≥2 tons of anthracite coal/year. Suggestive positive associations in relation to higher tonnage were also observed for ischemic heart disease. Changing from the traditional use of an unvented firepit to a portable or vented stove was associated with a reduction in overall mortality (HR=0.70, 95% CI=0.61-0.80 in men; HR=0.72, 95% CI=0.61-0.85 in women). Consistent sex-specific reductions in risk were observed for pneumonia and ischemic heart disease mortality, and a non-significant reduction in total cancer mortality was also observed for those who changed to using a portable or vented stove. Our findings suggest that anthracite coal use contributes to the burden of mortality in XW. This study emphasizes the importance of reducing the use of anthracite coal, which is still widely used in China for indoor cooking and heating, in favor of alternative fuel sources such as gas/electricity where possible. Citation Format: Bryan Bassig, Bingshu E. Chen, Wei Jie Seow, Roel Vermeulen, Jinming Zhang, Wei Hu, Jason Wong, Bofu Ning, H.Dean Hosgood, Yunchao Huang, Kaiyun Yang, George S. Downward, Lützen Portengen, Nathaniel Rothman, Qing Lan. Annual coal use and stove improvement in relation to cause-specific mortality in a 36-year cohort analysis among anthracite coal users in Xuanwei, China [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3238.