title: Controlled exposure to diesel exhaust causes increased nitrite in exhaled breath condensate among subjects with asthma.
abstract: OBJECTIVE
  To determine whether oxidative/nitrosative stress plays a role in the acute effects of diesel exhaust (DE) on subjects with asthma.
  
  
  METHODS
  In this crossover study, 16 subjects with mild to moderate asthma were exposed to clean filtered air or diluted DE (300 μg/m as PM2.5) for 1 hour with intermittent exercise.
  
  
  RESULTS
  Airway hyperreactivity increased 24 hours after exposure to DE compared with clean filtered air (PC20, 14.9 mg/mL vs 19.7 mg/mL; P = 0.012). Nitrite in exhaled breath condensate was elevated immediately after diesel exposure (P = 0.052) and remained elevated 4 and 24 hours after exposure.
  
  
  CONCLUSIONS
  After exposure to DE, subjects with asthma demonstrated increased airway hyperreactivity and obstruction. Increased nitrite in exhaled breath condensate, in the absence of increased exhaled nitric oxide, suggests a noninflammatory oxidative stress mechanism by which DE affects the lung.
authors.affiliation: Department of Pulmonary and Critical Care Medicine, University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, New Brunswick, NJ, USA. hussaisa@umdnj.edu
authors.forename: Sabiha
authors.initials: S
authors.lastname: Hussain
authors.forename: Robert
authors.initials: R
authors.lastname: Laumbach
authors.forename: Jakemia
authors.initials: J
authors.lastname: Coleman
authors.forename: Hatim
authors.initials: H
authors.lastname: Youssef
authors.forename: Kathie
authors.initials: K
authors.lastname: Kelly-McNeil
authors.forename: Pamela
authors.initials: P
authors.lastname: Ohman-Strickland
authors.forename: Junfeng
authors.initials: J
authors.lastname: Zhang
authors.forename: Howard
authors.initials: H
authors.lastname: Kipen
mesh_terms: D000328:Adult; D001249:Asthma / Q000378:metabolism*; D001944:Breath Tests / Q000379:methods*; D018592:Cross-Over Studies; D015444:Exercise / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009573:Nitrites / Q000032:analysis / Q000378:metabolism*; D018384:Oxidative Stress / Q000502:physiology; D001335:Vehicle Emissions / Q000032:analysis / Q000633:toxicity*; D055815:Young Adult
chemical_list: D009573:Nitrites; D001335:Vehicle Emissions