Smog, smog, go away

Nine of the 10 most ozone-polluted cities in the nation are in California, an American Lung Association report finds.

The top-five worst regions for ozone pollution are Los Angeles-Long Beach-Riverside, Visalia-Porterville, Bakersfield-Delano, Fresno-Madera and Hanford-Corcoran, according to California Healthline. According to the report, 90 percent of Californians live in counties that received a failing grade for ozone or particle pollution, and no city in California was among the 25 cleanest cities in the nation. The report did note some improvement, as Los Angeles recorded the lowest level of smog in the report’s 13-year history.

The report has been issued annually since 2000 and has consistently ranked California’s air among the most polluted in the nation due in part to the warm, dry climate that tends to trap smog in Southern California and the Central Valley.