Where is the worst air in the United States?

Where are the worst places to live in the US?  These cities have the worst short-term pollution spikes which are responsible for major health problems.  The sources of particle pollution can range from woodstoves and diesel trucks to coal power plants and heavy highway traffic.    These short-term spikes that increase the number of emergency room visits for asthma and other respiratory diseases, along with higher risk of heart attack, strokes, and early death among residents.

Pittsburgh, Pennsylvania took the dubious honor and California cities were all over the list as Fresno, Bakersfield and Los Angeles were all in the top 5 worst cities for air quality.   Birmingham, Alabama took the 5th spot.  Salt Lake City came in 6th.