Effects of short-term exposure to ambient nitrogen dioxide concentrations on human bronchial reactivity and lung function.
Eight normal and 8 asthmatic subjects were exposed to NO2 in a modified body box for plethysmography during 20 min at 0,230,460 and 910 micrograms/m3 on 4 separate days. Bronchial reactivity (histamine inhalation test) was measured after exposure to air alone and to 910 micrograms/m3NO2. Airway resistance (Raw), thoracic gas volume (TGV) and specific airway resistance (SRaw) were measured before, during and after exposure. The bronchial reactivity of the asthmatic subjects increased significantly (p = 0.04) by 20 min exposure to 910 micrograms/m3 NO2. In the non-asthmatic group the airway resistance increased significantly (p = 0.03) after 20 min exposure to 460 micrograms/m3 NO2 and decreased significantly (p = 0.01) after 20 min exposure to 910 micrograms/m3 NO2. In the asthmatic group the trend in airway resistance was the same but not statistically significant. In the latter group TGV was significantly decreased (p = 0.02) during exposure to 910 micrograms/m3 NO2. Short term NO2-exposure in concentrations even below 1000 micrograms/m3 seems to have effects on human bronchial reactivity and lung function.
D000293:Adolescent; D000328:Adult; D000393:Air Pollutants / Q000009:adverse effects*; D000403:Airway Resistance / Q000187:drug effects; D001249:Asthma / Q000503:physiopathology; D001980:Bronchi / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D008168:Lung / Q000187:drug effects* / Q000503:physiopathology; D008176:Lung Volume Measurements; D008297:Male; D008875:Middle Aged; D009585:Nitrogen Dioxide / Q000009:adverse effects*; D009812:Odorants; D012119:Respiration / Q000187:drug effects; D013997:Time Factors
D000393:Air Pollutants; D009585:Nitrogen Dioxide