title: Personal exposure to fine particulate matter, lung function and serum club cell secretory protein (Clara).
abstract: BACKGROUND
  The underlying mechanisms about the association between ambient fine particulate matter (PM2.5) and lung function were unclear. Few epidemiological studies have evaluated the potential mediating effects of serum club cell secretory protein (Clara) (CC16), a biomarker of pulmonary epithelium integrity.
  
  
  OBJECTIVE
  To evaluate the short-term effect of personal PM2.5exposure on lung function and to explore the potential mediating role of CC16 in this effect.
  
  
  METHODS
  We enrolled 36 healthy, nonsmoking college students for a panel study in Shanghai, China from December 17, 2014 to July 11, 2015. We measured personal and real-time exposure to PM2.5for 72 h preceding each of four rounds of health examinations, including lung function test and serum CC16 measurement. We used linear mixed-effect models to examine the effects of PM2.5on lung function and CC16 over various lag times. Furthermore, we analyzed the mediating effect of CC16 in the association between PM2.5and lung function.
  
  
  RESULTS
  Average PM2.5exposure ranged from 36 to 52 μg/m3 across different lag periods. PM2.5exposure was negatively associated with lung function and positively associated with serum CC16 concentration. The effect of PM2.5on CC16 occurred earlier than that on lung function. For instance, an interquartile range (IQR) increase in 0-2 h average exposure to PM2.5was significantly associated with a 4.84% increase in serum CC16; and an IQR increase in 3-6 h average exposure to PM2.5was significantly associated with a 1.08% decrease in 1-sec forced expiratory volume. These effects lasted up to 24 h after exposure. Increased serum CC16 contributed 3.9%-36.3% of the association between PM2.5and impaired lung function.
  
  
  CONCLUSIONS
  Acute exposure to PM2.5might induce an immediate decrease in lung function by virtue of the loss of pulmonary epithelium integrity.
authors.affiliation: School of Public Health, Key Lab of Public Health Safety of the Ministry of Education and Key Lab of Health Technology Assessment of the Ministry of Health, Fudan University, Shanghai 200032, China.
authors.forename: Cuicui
authors.initials: C
authors.lastname: Wang
authors.affiliation: School of Public Health, Key Lab of Public Health Safety of the Ministry of Education and Key Lab of Health Technology Assessment of the Ministry of Health, Fudan University, Shanghai 200032, China; Shanghai Key Laboratory of Meteorology and Health, Shanghai 200030, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Cai
authors.affiliation: School of Public Health, Key Lab of Public Health Safety of the Ministry of Education and Key Lab of Health Technology Assessment of the Ministry of Health, Fudan University, Shanghai 200032, China; Shanghai Key Laboratory of Meteorology and Health, Shanghai 200030, China.
authors.forename: Renjie
authors.initials: R
authors.lastname: Chen
authors.affiliation: School of Public Health, Key Lab of Public Health Safety of the Ministry of Education and Key Lab of Health Technology Assessment of the Ministry of Health, Fudan University, Shanghai 200032, China.
authors.forename: Jingjin
authors.initials: J
authors.lastname: Shi
authors.affiliation: School of Public Health, Key Lab of Public Health Safety of the Ministry of Education and Key Lab of Health Technology Assessment of the Ministry of Health, Fudan University, Shanghai 200032, China.
authors.forename: Changyuan
authors.initials: C
authors.lastname: Yang
authors.affiliation: School of Public Health, Key Lab of Public Health Safety of the Ministry of Education and Key Lab of Health Technology Assessment of the Ministry of Health, Fudan University, Shanghai 200032, China.
authors.forename: Huichu
authors.initials: H
authors.lastname: Li
authors.affiliation: School of Public Health, Key Lab of Public Health Safety of the Ministry of Education and Key Lab of Health Technology Assessment of the Ministry of Health, Fudan University, Shanghai 200032, China.
authors.forename: Zhijing
authors.initials: Z
authors.lastname: Lin
authors.affiliation: School of Public Health, Key Lab of Public Health Safety of the Ministry of Education and Key Lab of Health Technology Assessment of the Ministry of Health, Fudan University, Shanghai 200032, China.
authors.forename: Xia
authors.initials: X
authors.lastname: Meng
authors.affiliation: School of Public Health, Key Lab of Public Health Safety of the Ministry of Education and Key Lab of Health Technology Assessment of the Ministry of Health, Fudan University, Shanghai 200032, China.
authors.forename: Cong
authors.initials: C
authors.lastname: Liu
authors.affiliation: School of Public Health, Key Lab of Public Health Safety of the Ministry of Education and Key Lab of Health Technology Assessment of the Ministry of Health, Fudan University, Shanghai 200032, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Niu
authors.affiliation: School of Public Health, Key Lab of Public Health Safety of the Ministry of Education and Key Lab of Health Technology Assessment of the Ministry of Health, Fudan University, Shanghai 200032, China.
authors.forename: Yongjie
authors.initials: Y
authors.lastname: Xia
authors.affiliation: School of Public Health, Key Lab of Public Health Safety of the Ministry of Education and Key Lab of Health Technology Assessment of the Ministry of Health, Fudan University, Shanghai 200032, China.
authors.forename: Zhuohui
authors.initials: Z
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Reproduction Regulation of NPFPC, SIPPR, IRD, Fudan University, Shanghai 200032, China.
authors.forename: Weihua
authors.initials: W
authors.lastname: Li
authors.affiliation: School of Public Health, Key Lab of Public Health Safety of the Ministry of Education and Key Lab of Health Technology Assessment of the Ministry of Health, Fudan University, Shanghai 200032, China; Shanghai Key Laboratory of Meteorology and Health, Shanghai 200030, China; Key Laboratory of Reproduction Regulation of NPFPC, SIPPR, IRD, Fudan University, Shanghai 200032, China. Electronic address: haidongkan@gmail.com.
authors.forename: Haidong
authors.initials: H
authors.lastname: Kan
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000706:statistics & numerical data*; D015415:Biomarkers / Q000097:blood; D002681:China; D004781:Environmental Exposure / Q000032:analysis / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D016014:Linear Models; D008137:Longitudinal Studies; D008168:Lung / Q000737:chemistry; D008297:Male; D052638:Particulate Matter / Q000032:analysis*; D012129:Respiratory Function Tests
chemical_list: D000393:Air Pollutants; D015415:Biomarkers; D052638:Particulate Matter
keywords: Club cell secretory protein; Fine particulate matter; Lung function; Mediation effect; Personal exposure