title: Respiratory effects of a reduction in outdoor air pollution concentrations.
abstract: BACKGROUND
  Air pollution has been associated with respiratory health effects. There is little direct evidence that reductions in air pollution related to abatement policies lead to actual improvement in respiratory health. We assessed whether a reduction in (traffic policy-related) air pollution concentrations was associated with changes in respiratory health.
  
  
  METHODS
  Air pollution concentrations and respiratory health were measured in 2008 and 2010 at eight busy urban streets and at four suburban background control locations. Respiratory function was assessed twice in 661 residents by spirometry and measurements of airway resistance. Nitric oxide (NO) in exhaled air was measured as a marker for airway inflammation.
  
  
  RESULTS
  Air pollution concentrations were lower in 2010 than in 2008. The declines in pollutants varied among locations, with the largest decline observed in a street with a large reduction in traffic intensity. In regression analyses adjusted for important covariates, reductions in concentrations of soot, NO2, NOx, Cu, and Fe were associated with increases in forced vital capacity (FVC) (∼1% increase per interquartile range [IQR] decline). Airway resistance decreased with a decline in particulate matter (PM10) and PM2.5 (9% per IQR), although these associations were somewhat less consistent. No associations were found with exhaled NO. Results were driven largely by one street where traffic-related air pollution showed the largest reduction. Forced expiratory volume and FVC improved by 3% to 6% in residents of this street compared with suburban background residents. This was accompanied by a suggestive reduction in airway resistance.
  
  
  CONCLUSIONS
  Reductions in air pollution may lead to small improvements in respiratory function.
authors.affiliation: Institute for Risk Assessment Sciences, Division Environmental Epidemiology, Utrecht University, Utrecht, Netherlands.
authors.forename: Hanna
authors.initials: H
authors.lastname: Boogaard
authors.forename: Paul H
authors.initials: PH
authors.lastname: Fischer
authors.forename: Nicole A H
authors.initials: NA
authors.lastname: Janssen
authors.forename: Gerard P A
authors.initials: GP
authors.lastname: Kos
authors.forename: Ernie P
authors.initials: EP
authors.lastname: Weijers
authors.forename: Flemming R
authors.initials: FR
authors.lastname: Cassee
authors.forename: Saskia C
authors.initials: SC
authors.lastname: van der Zee
authors.forename: Jeroen J
authors.initials: JJ
authors.lastname: de Hartog
authors.forename: Kees
authors.initials: K
authors.lastname: Meliefste
authors.forename: Meng
authors.initials: M
authors.lastname: Wang
authors.forename: Bert
authors.initials: B
authors.lastname: Brunekreef
authors.forename: Gerard
authors.initials: G
authors.lastname: Hoek
mesh_terms: D000293:Adolescent; D000328:Adult; D000393:Air Pollutants / Q000032:analysis; D000397:Air Pollution / Q000032:analysis / Q000517:prevention & control*; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D009426:Netherlands; D009569:Nitric Oxide / Q000032:analysis; D011640:Public Policy; D012129:Respiratory Function Tests; D012140:Respiratory Tract Diseases / Q000503:physiopathology*; D014504:Urban Health / Q000706:statistics & numerical data*; D001335:Vehicle Emissions / Q000517:prevention & control*; D055815:Young Adult
chemical_list: D000393:Air Pollutants; D001335:Vehicle Emissions; D009569:Nitric Oxide