title: Inhalation of fine particulate air pollution and ozone causes acute arterial vasoconstriction in healthy adults.
abstract: BACKGROUND
  Fine particulate air pollution and ozone are associated with increased cardiovascular events. To help explain the mechanism behind these observations, we investigated the effect of air pollution exposure on vascular function.
  
  
  RESULTS
  Twenty-five healthy adults underwent a randomized, double-blind, crossover study comparing the vascular response to the 2-hour inhalation of approximately 150 microg/m(3) of concentrated ambient fine particles (CAP) plus ozone (120 ppb) versus the response to the inhalation of filtered air. High-resolution vascular ultrasonography was used to measure alterations in brachial artery diameter, endothelial-dependent flow-mediated dilatation (FMD) and endothelial-independent nitroglycerin-mediated dilatation (NMD). Exposure to CAP plus ozone caused a significant brachial artery vasoconstriction compared with filtered air inhalation (-0.09+/-0.15 mm versus +0.01+/-0.18 mm, P=0.03). There were no significant differences in FMD (+0.29+/-4.11% versus -0.03+/-6.63%, P=0.88), NMD (+3.87+/-5.43% versus +3.46+/-7.92%, P=0.83), or blood pressure responses between exposures.
  
  
  CONCLUSIONS
  Short-term inhalation of fine particulate air pollution and ozone at concentrations that occur in the urban environment causes acute conduit artery vasoconstriction.
authors.affiliation: University of Michigan, Ann Arbor, USA. Robdbrok@umich.edu
authors.forename: Robert D
authors.initials: RD
authors.lastname: Brook
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Brook
authors.forename: Bruce
authors.initials: B
authors.lastname: Urch
authors.forename: Renaud
authors.initials: R
authors.lastname: Vincent
authors.forename: Sanjay
authors.initials: S
authors.lastname: Rajagopalan
authors.forename: Frances
authors.initials: F
authors.lastname: Silverman
mesh_terms: D000328:Adult; D000393:Air Pollutants / Q000009:adverse effects / Q000737:chemistry; D000397:Air Pollution / Q000009:adverse effects*; D001158:Arteries / Q000000981:diagnostic imaging / Q000502:physiology*; D001916:Brachial Artery / Q000502:physiology; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D019570:Inhalation Exposure; D008297:Male; D010126:Ozone / Q000008:administration & dosage / Q000009:adverse effects*; D010316:Particle Size; D014463:Ultrasonography; D014661:Vasoconstriction; D014664:Vasodilation
chemical_list: D000393:Air Pollutants; D010126:Ozone