title: [Assessment of haze-related human health risks for four Chinese cities during extreme haze in January 2013].
abstract: OBJECTIVE
  To evaluate the human health risks (premature death risk as an indicator) in Beijing, Shanghai, Guangzhou and Xi'an during extreme haze in January 2013.
  
  
  METHODS
  The daily average particulate matter ≤ 2.5 µm in aerodynamic diameter (PM2.5) concentrations of Beijing, Shanghai, Guangzhou and Xi'an in January 2013 were collected and their characteristics explored. The populations and mortality rate of four cities in 2010 were collected from the statistical yearbook, the exposure-response relationships selected from the reference and then the premature death calculated according to the proportion risk model of Poisson regression.
  
  
  RESULTS
  In January 2013, the 24 h mean concentrations of PM2.5 in Beijing, Shanghai, Guangzhou and Xi'an were (240 ± 165) , (83 ± 27), (94 ± 49) and (210 ± 98) µg/m(3) respectively and they were all above the secondary level of Ambient Air Quality Standards (GB 3095-2012). The 24 h mean concentrations of PM2.5 in Beijing and Xi'an were much higher than those in Shanghai and Guangzhou. Approximately 86.4% (19/22) , 58.1% (18/31), 54.8% (17/31) and 93.5% (29/31) of 24 h mean PM2.5 concentrations in Beijing, Shanghai, Guangzhou and Xi'an respectively exceeded the secondary level of Ambient Air Quality Standards (GB 3095-2012). The number of premature death due to the exposure to haze were 725 (95%CI: 457-977) for Beijing, 296 (95%CI: 96-502) for Shanghai, 310 (95%CI: 189-434) for Guangzhou and 85 (95%CI: 21-141) for Xi'an respectively in January 2013.
  
  
  CONCLUSIONS
  The PM2.5 pollutions of four cities in January 2013 were serious enough to pose elevated risks of human health.
authors.affiliation: Research office of Environmental Health Risk Assessment, Institute of Environmental Health & Related Product Safety, Chinese Center for Disease Control & Prevention, Beijing 100021, China.
authors.forename: Tian-tian
authors.initials: TT
authors.lastname: Li
authors.forename: Yan-jun
authors.initials: YJ
authors.lastname: Du
authors.forename: Yang
authors.initials: Y
authors.lastname: Mo
authors.forename: Wen-bo
authors.initials: WB
authors.lastname: Xue
authors.affiliation: Institute of Environmental Health & Related Product Safety, Chinese Center for Disease Control & Prevention, Beijing 100021, China. Email: dongqunxu@126.com.
authors.forename: Dong-qun
authors.initials: DQ
authors.lastname: Xu
authors.affiliation: State Environmental Protection Key Laboratory of Environmental Planning & Policy Simulation, Chinese Academy for Environmental Planning, Beijing 100012, China, Email: wangjn@caep.org.cn.
authors.forename: Jin-nan
authors.initials: JN
authors.lastname: Wang
mesh_terms: D000397:Air Pollution / Q000009:adverse effects*; D002681:China; D002947:Cities; D004781:Environmental Exposure / Q000009:adverse effects*; D006801:Humans; D052638:Particulate Matter / Q000009:adverse effects; D018570:Risk Assessment
chemical_list: D052638:Particulate Matter