Respiratory responses of asthmatics to ozone

Asthmatic individuals in the general population appear to be susceptible to disease exacerbation during summertime 'smog' episodes (ambient air pollution containing other pollutants in addition to ozone). Although controlled exposure to ozone causes acute decrements in lung function, asthmatic subjects are only marginally more susceptible to these effects. Ozone exposure also causes respiratory tract inflammatory changes, both in normals and asthmatics. Recent studies suggest that ozone pre-exposure augments the responses of allergic asthmatics to nasal and inhalation challenge with specific antigen. This may offer one possible explanation for the findings of field studies.