| ||Format||Pages||Price|| |
|PDF (68K)||4||$25||  ADD TO CART|
|Complete Source PDF (4.2M)||238||$60||  ADD TO CART|
Current concepts of the nature of asthma and of the effects of ozone on the lungs and airways seem logically to predict that people with asthma should have heightened sensitivity to the adverse effects of exposure to ozone. At least some epidemiologic studies seem to bear out this expectation, showing an association between asthmatic attacks and daily, 1-h, maximum ozone concentrations, but direct studies of acute exposure do not. The doses of ozone needed to cause significant changes in tests of airway caliber and of bronchial reactivity in asthmatic subjects do not appear to differ greatly from those needed in healthy subjects. Studies of guinea pigs and monkeys suggest, however, that ozone may have an indirect effect on the severity or even the occurrence of asthma by increasing the ease of sensitization to inhaled allergens, perhaps because of the increase in airway mucosal permeability caused by ozone exposure.
ozone, epidemiologic studies, asthma, air pollution
Professor of medicine, University of California, San Francisco, CA