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

The Los Angeles-Long Beach ranked as the nation’s smoggiest region in a report released Wednesday by the American Lung ...

The Los Angeles-Long Beach ranked as the nation’s smoggiest region in a report released Wednesday by the American Lung Association, which also faulted the region for short-term and year-round particle ...

The Environmental Protection Agency (EPA) chief on Tuesday demanded that Mexico put an end to the unfettered flow of raw sewage from the Tijuana region into Southern California. “Mexico ...

Cities in California make up a significant proportion of the country's most polluted metropolitan areas when it comes to air ...

Nearly half of all Americans now live in places with unhealthy air, and the Bay Area metro is among the top 20 in poor air quality.