Date of Award
Civil and Environmental Engineering
Beijing, Health risks, PM2.5, spatial, temporal, Windsor
High concentrations of PM2.5 and the corresponding health effect in Beijing, China have drawn attention worldwide. This study aims to assess the lifetime health risk of ambient PM2.5 bound elements and polycyclic aromatic hydrocarbons (PAHs) from 2013 to 2015 in Beijing. Risk assessment methods of US Environment Protection Agency (USEPA) were applied to the following PM2.5 components: six elemental components (Cr, Co, Ni, As, Cd, Pb) and sixteen EPA priority PAHs for cancer risks, and thirteen non- elemental components (Al, Ba, Cr, Mn, Ni, As, Cd, Pb, Co, V, P, Cl, Se) for non-cancer risks. Spatial and temporal variations of health risks were examined across Beijing. Source apportionment was applied to apportion the risks. The estimated lifetime cancer risk due to exposure to ambient PM2.5 in Beijing is 2.30E-02. This cancer risk level is two magnitudes higher than EPA upper threshold of 1.00E-04. Thus, remediation is desirable. Lifetime non-cancer hazard quotient in Beijing is 13.7, higher than EPA upper threshold of non-cancer hazard quotient (1.0), indicating that some non-cancer health impacts may also occur. Seasonal cancer risks range 7.47E-03 to 4.78E-03. Summer and winter have higher percentages of 31% and 26% respectively to the total lifetime risk, while lower in spring (23%), and autumn (20%). Seasonal non-cancer hazard quotients in Beijing range 4.5 to 26.2. Winter contributed approximate 52% of total non-cancer hazard quotient, followed by spring (21%), autumn (18%), and summer (9%). Lifetime cancer risk is higher in suburban area (3.53E-02) than in urban area (1.82E-02), while hazard quotient is higher in urban area (14.3) than suburban area (2.6). Overall, both lifetime cancer and non-cancer risks in Beijing are higher than the corresponding USEPA threshold. The health risks in Beijing are all higher than other cities in China, Windsor, and Mexico.
Chen, Yangfan, "Levels of PM2.5-bound species in Beijing, China: Spatio-temporal distributions and human health risks" (2017). Electronic Theses and Dissertations. 5972.