(May 23, 2000) - Coming in 6th on a list that's topped by the Los Angeles-Riverside-Orange County Region, the San Diego and Imperial County Region ranks among the country's worst in ozone pollution, according to a "State of the Air 2000" analysis released today by the American Lung Association. Locally, the Association is calling for municipal governments to help create demand for Zero Emission Vehicles as a positive step toward resolving bad air quality.

Ozone is a highly-reactive form of oxygen, O3. Ozone's reactive properties make it beneficial in the ozone layer, in earth's upper atmosphere, where it absorbs ultra-violet light frequencies that would otherwise damage life on the earth's surface. At ground level, however, ozone's reactive properties make it dangerous to lung tissue.

Ozone is the classic example of chemicals known as "free radicals," unstable molecules that seek immediate, sometimes violent, reactions with other molecules in order to achieve chemical stability. Ozone readily "oxidizes" nearby molecules so it can transform into oxygen's more stable form of O2. Breathing ozone causes lung tissues to become inflamed and worsens lung disease. As the public learns more about the health effects of air pollution, the American Lung Association hopes for stronger public support of clean air policies at all levels of government.

Ozone exposure may lead to shortness of breath, chest pain when inhaling deeply, wheezing and coughing. Long term, repeated exposure may lead to large reductions in lung function, inflammation, and pain. The EPA estimates that 5 to 20 percent of the U.S. population is especially susceptible to ozone pollution, with children at higher risk because of their higher breathing rates, which expose them to relatively larger doses of air pollution.

In its "State of the Air 2000" report, the American Lung Association analyzes ozone pollution trends from 1996 to 1998. While on the average the nation has made strides against air pollutants such as lead, sulfur dioxide, and carbon monoxide, less progress has been made against particulate matter (PM) and ozone.

In San Diego and Imperial Counties, San Diego has made progress in reducing ozone emissions, but continues to violate the federal health standard governing average ozone concentrations during an 8-hour period. From 1996-98, this standard was violated on 79 days in San Diego County and on 102 days in Imperial County, with concentrations severe enough to earn the region an "F" using the American Lung Association's rating system.

"Even though there's no single solution to the ozone pollution problem, we can all do something to address air pollution," said Jan Cortez, Vice President for Research and Environmental Health for the American Lung Association of San Diego and Imperial Counties. "Motor vehicles must emit less, which implies both personal actions and new policies to reduce pollution."

The local American Lung Association is calling for local city governments to adopt policies that would use more Zero Emission Vehicles (ZEVs) in their fleets.

"The impact of this ordinance would sustain the demand for Zero Emission Vehicles, spurring car makers to continue their efforts to make these cleaner vehicles and increasing the visibility and viability of this technology," Cortez said.

Individuals can carpool, walk, bicycle, use mass transit, combine their driving trips, and seek out lower-polluting vehicles, she added.

Among the findings of the "State of the Air 2000" report is a list of the 25 metropolitan areas with the worst ozone air pollution, using 1996-98 data, below.

1. Los Angeles-Riverside-Orange County, CA 2. Bakersfield, CA 3. Fresno, CA 4. Visalia-Tulare-Porterville, CA 5. Houston-Galveston-Brazoria, TX 6. San Diego-Imperial County, CA 7. Washington, DC/Baltimore 8. Charlotte Gastonia-Rock Hill, NC 9. Atlanta, GA 10. Merced, CA 11. Sacramento-Yolo, CA 12. Knoxville, TN 13. Philadelphia, PA-Wilmington, DE- Atlantic City, NJ

14. Dallas-Fort Worth, TX 15. Redding, CA 16. New York-Northern NJ-Long Island, NY 17. Raleigh-Durham-Chapel Hill, NC 18. Nashville, TN 19. Phoenix-Mesa, AZ 20. Modesto, CA 21. Pittsburgh, PA 22. Lancaster, PA 23. Memphis, TN 24. Birmingham, AL 25. St. Louis, MO

"We need strong rules in Sacramento that support Zero Emission Vehicles. Nationally, we need to make sure the EPA monitors pollution and revises standards to maintain public health. Here in San Diego and Imperial Counties, we must continue exploring ways to reduce traffic and fight sources of toxic air pollution. We must concurrently develop health education and treatment strategies for people - especially children and the elderly - who suffer the effects of poor lung function," said Dr. Kevin Murray, a lung health specialist volunteer with the American Lung Association.