title: Traffic-related air pollution and lung function in children at 8 years of age: a birth cohort study.
abstract: BACKGROUND
  Long-term exposure to air pollution has been related to lung function decrements in children, but the role of timing of exposure remains unknown.
  
  
  OBJECTIVE
  To assess the role of long-term exposure to air pollution on lung function in school-age children.
  
  
  METHODS
  More than 1,900 children in the Swedish birth cohort BAMSE were followed with repeated questionnaires, dynamic spirometry, and IgE measurements until 8 years of age. Outdoor concentrations of particulate matter with an aerodynamic diameter less than 10 μm (PM(10)) from road traffic were estimated for residential, day care, and school addresses from birth and onward using dispersion modeling. The relationship between time-weighted average exposure during different time windows and FEV at 8 years was analyzed by linear regression, adjusting for potential confounding factors, including short-term exposure to air pollution.
  
  
  RESULTS
  A 5th to 95th percentile difference in time-weighted average particulate matter less than 10 μm in aerodynamic diameter exposure during the first year of life was associated with a reduced FEV(1) of -59.3 ml (95% confidence interval, -113 to -5.6) at 8 years of age. The negative association was particularly pronounced in children concomitantly sensitized to common inhalant or food allergens (-136.9 ml; 95% confidence interval, -224.1 to -49.7). Exposure after the first year of life seemed to have less impact on lung function at 8 years.
  
  
  CONCLUSIONS
  Our results indicate that exposure to traffic-related air pollution during infancy affects lung function in children up to 8 years of age and particularly in those sensitized to common inhalant or food allergens.
authors.affiliation: Institute of Environmental Medicine, Karolinska Institute, Stockholm, Sweden.
authors.forename: Erica S
authors.initials: ES
authors.lastname: Schultz
authors.forename: Olena
authors.initials: O
authors.lastname: Gruzieva
authors.forename: Tom
authors.initials: T
authors.lastname: Bellander
authors.forename: Matteo
authors.initials: M
authors.lastname: Bottai
authors.forename: Jenny
authors.initials: J
authors.lastname: Hallberg
authors.forename: Inger
authors.initials: I
authors.lastname: Kull
authors.forename: Magnus
authors.initials: M
authors.lastname: Svartengren
authors.forename: Erik
authors.initials: E
authors.lastname: Melén
authors.forename: Göran
authors.initials: G
authors.lastname: Pershagen
mesh_terms: D000397:Air Pollution / Q000009:adverse effects*; D002648:Child; D004784:Environmental Monitoring; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000150:complications*; D007073:Immunoglobulin E / Q000032:analysis; D016014:Linear Models; D008168:Lung / Q000187:drug effects* / Q000503:physiopathology; D008297:Male; D052638:Particulate Matter / Q000009:adverse effects*; D011446:Prospective Studies; D013147:Spirometry; D011795:Surveys and Questionnaires; D013548:Sweden; D013995:Time; D001335:Vehicle Emissions / Q000633:toxicity*
chemical_list: D052638:Particulate Matter; D001335:Vehicle Emissions; D007073:Immunoglobulin E