Specialized vehicles are collecting block-by-block air quality data in Bakersfield as part of a $27 million statewide ...

California cities nearly covered all five spots in the Top 5 Most Polluted Cities when it comes to year-round particle pollution in the U.S., according to the American Lung Association.

Ozone pollution isn’t just a California problem, as nearly 25 million more people across the nation, based on last year's figure, have been exposed to ozone levels that put their health at risk.