title: Prolonged respiratory symptoms caused by thermal degradation products of freons.
abstract: OBJECTIVE
  The chlorofluorocarbons (CFC) used in refrigeration systems decompose on heating and produce substances that are highly irritating to the airways (eg, chlorine, carbonyl fluoride, and hydrogen fluoride). This study examined persistent respiratory symptoms among several workers exposed to thermal decomposition products of CFC.
  
  
  METHODS
  Seven patients with respiratory symptoms caused by inadvertent exposure to thermal decomposition products of CFC in a restaurant kitchen or during refrigerator repair were studied with the use of spirometry, peak flow follow-up, and histamine challenge tests. Three patients also underwent bronchoscopy and bronchoalveolar lavage.
  
  
  RESULTS
  In five of the cases, cough or dyspnea lasted longer than 1 month; for three of the five, the symptoms lasted more than 4 years. Three cases showed increased bronchial hyperreactivity, and two of the three had increased diurnal peak flow variation. Three patients fulfilled the criteria for acute irritant-induced asthma or reactive airway dysfunction syndrome. One case exhibited bronchiolitis while, for the other six, the clinical picture was consistent with bronchitis.
  
  
  CONCLUSIONS
  The studied cases indicate that the thermal decomposition products of CFC used in refrigerators may cause irritant-induced airway diseases of long duration.
authors.affiliation: Department of Occupational Medicine, Finnish Institute of Occupational Health, Helsinki, Finland. paivi.piirila@hus.fi
authors.forename: Päivi
authors.initials: P
authors.lastname: Piirilä
authors.forename: Timo
authors.initials: T
authors.lastname: Espo
authors.forename: Pirkko
authors.initials: P
authors.lastname: Pfäffli
authors.forename: Vesa
authors.initials: V
authors.lastname: Riihimäki
authors.forename: Henrik
authors.initials: H
authors.lastname: Wolff
authors.forename: Henrik
authors.initials: H
authors.lastname: Nordman
mesh_terms: D000328:Adult; D016535:Bronchial Hyperreactivity / Q000139:chemically induced*; D001992:Bronchoalveolar Lavage Fluid; D001999:Bronchoscopy; D005617:Chlorofluorocarbons, Methane / Q000009:adverse effects* / Q000737:chemistry; D003371:Cough / Q000139:chemically induced*; D004417:Dyspnea / Q000139:chemically induced*; D005260:Female; D005387:Finland / Q000453:epidemiology; D006358:Hot Temperature; D006801:Humans; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure / Q000009:adverse effects*; D013147:Spirometry
chemical_list: D005617:Chlorofluorocarbons, Methane