PROLONGED ACUTE EXPOSURE TO 0.16 PPM OZONE INDUCES EOSINOPHILIC AIRWAY INFLAMMATION IN ASTHMATIC SUBJECTS WITH ALLERGIES

Background: Increased ambient ozone levels have been associated with i ncreased asthma morbidity in epidemiologic studies. Given that asthma is characterized by airway inflammation and increased sensitivity to a irway irritants, it has been suggested that asthmatic subjects may be particularly sensitive to the effect of ozone. Objective: The objectiv e of this study was to determine whether exposure to 0.16 ppm ozone in duces eosinophilic inflammation in the lower airways of asthmatic subj ects. Methods: Eight asthmatic subjects sensitive to mites were expose d to 0.16 ppm ozone and clean air on separate occasions no less than 4 weeks apart in a double-blind, randomized fashion followed by broncho scopy 18 hours later. Bronchoalveolar lavage fluid and bronchial lavag e fluid were examined for eosinophils.Results: Ozone induced significa nt increases in airway eosinophils, especially in bronchial lavage flu id. Conclusions: Ozone exposure results in increased eosinophilic infl ammation in the lower airways of asthmatic subjects with allergies.