An annual report from the American Lung Assn. showed that Los Angeles has improved its air quality but still deserves its ...

The iconic skyline of downtown Los Angeles ... city by ozone for 25 of those years. The list is weighted based on the average number of unhealthy air days, the association says. Not only is ...

Los Angeles-Long Beach was found to have the worst ozone, or smog, pollution in the country. Five areas of California were listed among the top 10 most polluted areas, with Visalia placing second ...