Simulation and health risk assessment of residential particle pollution by coal combustion in China

In China, residential coal combustion has resulted in serious indoor air pollution, and the emitted particulate matters and associated toxic organic compounds are greatly harmful to human health. For example, the high lung cancer mortality in Xuanwei County, Yunnan Province was attributed to inhalation of polycyclic aromatic hydrocarbons (PAHs)-coated particles within the houses. Based on previous investigations, this paper simulated the indoor particle pollution from coal combustion for a typical home in Xuanwei by computational fluid dynamics (CFD) method. Benzo[a]pyrene (BaP), one of the important pollutants from incomplete combustion, was used as a criterion for its strong carcinogenicity in risk assessment. Mechanical exhaust fan was installed in order to reduce the concentration of suspended particles indoors. Based on the simulated results, an engineering-oriented method was demonstrated to be effective in assessing indoor particle pollution by coal combustion and its health effect. Results indicated that the indoor particle pollution was rather serious due to the poor ventilation. Women, who spent more time indoors than men, had higher risk for lung cancer, and the predicted incidence for local people accorded well with previous surveys [Chapman RS, Mumford JL, Harris DB. The epidemiology of lung cancer in Xuanwei, China: current process, issues and research strategies. Archives of Environmental Health 1988;43(2):180–5]. The installation of the exhaust fan turned out to be effective in removing indoor particles since it greatly strengthened airflows and the contaminant removal is significantly improved.