Objectives/Hypothesis:
The Clean Air Act of 1970 requires the U.S. Environmental Protection Agency to establish air quality standards that will protect sensitive populations from adverse health effects caused by air pollutants. These populations generally include the young, the elderly, and people with preexisting respiratory or heart disease. One such chronic respiratory disease is asthma, which is characterized by reversible airway obstruction, airway inflammation, and increased responsiveness of the airways to irritant stimuli such as ozone.
Approach:
Some evidence suggests that ozone-induced airway inflammation is greater in asthmatic adults than in healthy adults. A number of studies also have shown that both healthy and asthmatic children exposed to elevated levels of ozone can experience transient decreases in lung function and increases in respiratory symptoms such as cough or wheeze. Thus, it is reasonable to suspect that children with asthma may be more sensitive to ozone than other children. HEI supported this study by Avol, Peters, and colleagues because it was designed to evaluate the effects of ambient ozone on potentially sensitive population subgroups (asthmatic and wheezy children), and to comprehensively assess ozone exposure and health outcomes.
Expected Results:
Supplemental Keywords: Air, ambient air quality, air toxics, epidemiology, health effects, particulate matter, human health risk assessment, ozone, inhalation studies, human exposure, children's health, asthma, susceptibility
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Last Updated: April 22, 2002