L.A. isn’t anywhere near as bad as it was in the 1960s and early 70s, when smog alert days were a daily fact of life. Cleaner car engines have helped reduce those emissions. But smog and other forms of air pollution are still a problem in the L.A. metro area, while Long Beach experiences serious air pollution from one of the biggest maritime ports in the world.
The 10 Most Polluted Cities in America
Bakersfield, Merced and Fresno top the American Lung Association's list of cities with the most persistant air pollution in the country in 2013
#4 (tie): Los Angeles-Long Beach-Riverside, CA
Full List
10 U.S. Cities With The Dirtiest Air