The LA area is once again the worst for ozone in the U.S., a pollutant impacting millions more people nationwide, the ...

Los Angeles is the smoggiest U.S. city for the 25th time in 26 years, despite reducing unhealthy ozone days by 40% since 2000 ...

Despite decades of progress in reducing air pollution, Los Angeles is still the nation’s smoggiest city, according to a report released Wednesday by the American Lung Assn.

Monitoring systems are not all encompassing and do not always pick up all of the hundreds of harmful chemicals released, ...

UCLA's annual survey reveals growing concerns over the high cost of living and deportation fears among LA County residents.