title: Effect of formaldehyde on asthmatic response to inhaled allergen challenge.
abstract: BACKGROUND
  Exposure to formaldehyde may lead to exacerbation of asthma.
  
  
  OBJECTIVE
  Our aim in this study was to investigate whether exposure to a low level (500 microg/m(3)) of formaldehyde enhances inhaled allergen responses.
  
  
  METHODS
  Twelve subjects with intermittent asthma and allergy to pollen were exposed, at rest, in a double-blind crossover study to either formaldehyde or purified air for 60 min. The order of exposure to formaldehyde and air-only was randomized, and exposures were separated by 2 weeks. We also performed an allergen inhalation challenge after each exposure. Airway responsiveness to methacholine and lower airway inflammation (induced sputum) were assessed 8 hr after allergen challenge.
  
  
  RESULTS
  The median dose of allergen producing a 15% decrease in forced expiratory volume in 1 sec (PD(15)FEV(1)) was 0.80 IR (index of reactivity) after formaldehyde exposure compared with 0.25 IR after air-only exposure (p = 0.06). Formaldehyde exposure did not affect allergen-induced increase in responsiveness to methacholine (p = 0.42). We found no formaldehyde-associated effect on the airway inflammatory response, in particular the eosinophilic inflammatory response, induced by the allergen challenge 8 hr before.
  
  
  CONCLUSIONS
  In this study, exposure to 500 microg/m(3) formaldehyde had no significant deleterious effect on airway allergen responsiveness of patients with intermittent asthma; we found a trend toward a protective effect.
authors: Service des Etudes Médicales d'EDF et de Gaz de France, Paris, France. veronique.ezratty@edfgdf.fr
authors: Véronique
authors: V
authors: Ezratty
authors: Marcel
authors: M
authors: Bonay
authors: Catherine
authors: C
authors: Neukirch
authors: Gaëlle
authors: G
authors: Orset-Guillossou
authors: Monique
authors: M
authors: Dehoux
authors: Serge
authors: S
authors: Koscielny
authors: Pierre-André
authors: PA
authors: Cabanes
authors: Jacques
authors: J
authors: Lambrozo
authors: Michel
authors: M
authors: Aubier
mesh_terms: D000293:Adolescent; D000328:Adult; D000393:Air Pollutants / Q000633:toxicity*; D000485:Allergens / Q000276:immunology; D001249:Asthma / Q000175:diagnosis / Q000209:etiology* / Q000276:immunology; D005260:Female; D005557:Formaldehyde / Q000633:toxicity*; D006801:Humans; D019570:Inhalation Exposure; D008297:Male; D012129:Respiratory Function Tests; D013183:Sputum / Q000737:chemistry
chemical_list: D000393:Air Pollutants; D000485:Allergens; D005557:Formaldehyde