title: Effects of particulate air pollution and ozone on lung function in non-asthmatic children.
abstract: BACKGROUND
  Information on the long-term effects of different air pollutant levels on lung function is relatively lacking in Asia and still inconclusive in the world. Age differential effects of air pollution are not known.
  
  
  OBJECTIVE
  To assess the acute and subchronic effects of ambient air pollution on lung function and compared among children of different ages.
  
  
  METHODS
  From April to May 2011, a nationwide study was conducted on schoolchildren aged 6-15 years in 44 schools of 24 districts in Taiwan. Spirograms were obtained from 1494 non-asthmatic children. Air pollution data were retrieved from air monitoring stations within one kilometre of the schools. Using three-level hierarchical linear models, individual lung function was fitted to air pollution, with adjustments for demographics, indoor exposures, outdoor activity, and districts.
  
  
  RESULTS
  Lung function changes per inter-quartile increase of the past two-months average levels of particulate matter <2.5 μm (PM2.5) and ozone (12 μg/m(3), 32-44 and 6.7 ppb, 32-38, respectively) were -103 and -142 ml on FVC, -86 and -131 on FEV1, and -102 and -188 ml/s on MMEF, respectively. Lag-1-day ozone exposure was associated with decreased MMEF. In children aged 6-10, PM2.5 was associated with decreased FEV1/FVC and MMEF/FVC ratios.
  
  
  CONCLUSIONS
  In children aged 6-15 years, sub-chronic exposure to ambient PM2.5 and ozone leads to reduced lung capacity, whereas acute exposure to ozone decreases mid-expiratory flow. In children aged 6-10 years, additional airway obstructive patterns in lung function may be associated with PM2.5 exposure.
authors.affiliation: Department of Environmental and Occupational Medicine, National Taiwan University (NTU) College of Medicine and NTU Hospital, Taipei 100, Taiwan.
authors.forename: Chi-Hsien
authors.initials: CH
authors.lastname: Chen
authors.affiliation: Department of Environmental and Occupational Medicine, National Taiwan University (NTU) College of Medicine and NTU Hospital, Taipei 100, Taiwan; Institute of Occupational Medicine and Industrial Hygiene, National Taiwan University, Taipei 100, Taiwan.
authors.forename: Chang-Chuan
authors.initials: CC
authors.lastname: Chan
authors.affiliation: Institute of Occupational Medicine and Industrial Hygiene, National Taiwan University, Taipei 100, Taiwan.
authors.forename: Bing-Yu
authors.initials: BY
authors.lastname: Chen
authors.affiliation: Institute of Occupational Medicine and Industrial Hygiene, National Taiwan University, Taipei 100, Taiwan.
authors.forename: Tsun-Jen
authors.initials: TJ
authors.lastname: Cheng
authors.affiliation: Department of Environmental and Occupational Medicine, National Taiwan University (NTU) College of Medicine and NTU Hospital, Taipei 100, Taiwan; Institute of Occupational Medicine and Industrial Hygiene, National Taiwan University, Taipei 100, Taiwan. Electronic address: leonguo@ntu.edu.tw.
authors.forename: Yue
authors.initials: Y
authors.lastname: Leon Guo
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000393:Air Pollutants / Q000633:toxicity*; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D005540:Forced Expiratory Flow Rates; D005541:Forced Expiratory Volume; D006801:Humans; D019570:Inhalation Exposure; D008168:Lung / Q000187:drug effects* / Q000503:physiopathology*; D008297:Male; D009043:Motor Activity; D010126:Ozone / Q000633:toxicity*; D052638:Particulate Matter / Q000633:toxicity*; D012129:Respiratory Function Tests; D012140:Respiratory Tract Diseases / Q000209:etiology* / Q000503:physiopathology; D012737:Sex Factors; D013624:Taiwan; D014797:Vital Capacity
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter; D010126:Ozone
keywords: Air pollution; Children; Lung function; Obstructive; Ozone; PM(2.5); Small airway