Respiratory function changes from inhalation of polluted air

Exposure to polluted air may trigger respiratory symptoms in certain subjects. Maximal expiratory flow volume measurements and methacholine bronchial challenges were conducted in 25 asthmatics and 30 healthy volunteers, before and after breathing bagged polluted air for 30 min, to determine whether exposures to polluted air influence respiratory function and bronchial reactivity. No differences in forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1.0), total respiratory resistance (Rrs), and bronchial reactivity were noted for normal subjects after they inhaled polluted air and ambient air. Significant decreases in FEV1.0 and FEV1.0/FVC, an increase in airway reactivity, and elevation of baseline Rrs values occurred in the asthmatic subjects, after exposure to polluted air. These findings suggest that asthmatic patients are more vulnerable to the adverse effects of polluted air.