title: PM2.5-bound PAHs in three indoor and one outdoor air in Beijing: Concentration, source and health risk assessment.
abstract: Three indoor (residential home, dormitory, and office) and one outdoor concentrations of PM2.5-bound Polycyclic aromatic hydrocarbons (PAHs) were analyzed in Beijing across four seasons. The highest and lowest concentration of total PAHs for outdoor appeared in winter and in summer with averages of 200.1 and 9.1ng/m3respectively. The seasonal variations of total PAHs in three indoor sites were the same as outdoor. The correlation analysis between the indoor and outdoor samples showed that the annual mean I/O ratios of total PAHs in the three sites were lower than 1. Source apportionment showed vehicle exhaust, coal combustion, and biomass burning were the major contributors of indoor and outdoor PM2.5-bound PAHs. Indoor source, such as camphor pollution, was identified in the dormitory, while camphor pollution and cooking sources were identified in the residential home. The annual averages of Benzo[a]pyrene equivalent concentration (BaPeq) were 7.6, 7.8, 7.7 and 12.7ng/m3for the dormitory, office, residential home and outdoor samples respectively, far higher than the annual limit of 1ng/m3regulated by European Commission. Life lung cancer risk (LLCR) in four sites across four seasons were over the acceptable cancer risk level, showing the cancer risk were at a high level in both indoor and outdoor sites in Beijing, and its level in indoor sites was much lower than in the outdoor site. The health risk assessment indicated the level of PAHs cancer risk on human for three indoor sites were similar. The results call for the development of more stringent control measures to reduce PAHs emissions.
authors.affiliation: School of Space and Environment, Beihang University, Beijing 100191, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Chen
authors.affiliation: School of Space and Environment, Beihang University, Beijing 100191, China. Electronic address: lixinghua@buaa.edu.cn.
authors.forename: Xinghua
authors.initials: X
authors.lastname: Li
authors.affiliation: School of Space and Environment, Beihang University, Beijing 100191, China. Electronic address: zhutl@buaa.edu.cn.
authors.forename: Tianle
authors.initials: T
authors.lastname: Zhu
authors.affiliation: School of Space and Environment, Beihang University, Beijing 100191, China.
authors.forename: Yingjie
authors.initials: Y
authors.lastname: Han
authors.affiliation: School of Space and Environment, Beihang University, Beijing 100191, China.
authors.forename: Dong
authors.initials: D
authors.lastname: Lv
keywords: Beijing; Health risk; Indoor air; Outdoor air; PAHs; Source identification