"If it is a high-alert day, drive less and don't burn wood or trash," she said.
Unfortunately, only about a third of counties in the United States have air-quality monitors, because they are expensive to install and collect, Nolen said. For the first time, however, this year's report has information on every county, using data from nearby cities and counties for areas that don't have their own monitors.
Both ozone and particle pollution can affect respiratory health, worsening breathing and increasing the risk of asthma attacks, respiratory infections and chronic obstructive pulmonary disease (COPD).
"People thought problems were limited to the lungs, but over the past 15 years quite a bit of work has shown things like cardiovascular effects," Hertz-Picciotto said. Studies have found links between high levels of ozone and soot and increased risk of heart attacks and stroke, as well as lower birth weights and increased risk of infant mortality.
Air quality can have the biggest effect on vulnerable groups of people, including young children, older adults and people with weak immune systems, Hertz-Picciotto said.
You can find information about AIRNow and your local air quality and air pollution in general at the National Association of Clean Air Agencies.
SOURCES: Janice Nolen, assistant vice president, national policy and advocacy, American Lung Association, Washington, D.C.; Irva Hertz-Picciotto, Ph.D., M.P.H., professor, chief, environmental and occupational health, department of public health sciences, University of California, Davis; American Lung Association report, State of the Air 2013
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