12. El Centro, CA
In this city that ranks 12th in our list of most polluted cities in the US in 2017, there is 3,652 out of total population who are dealing with pediatric asthma and 9,933 with adult one. Moreover, besides the ranking for the ozone days, which is 14th, El Centro is ranked 11th for 24-hour particle pollution out of 186 metropolitan areas and 7th for annual particle pollution out of 184 metropolitan areas.
Pixabay/Public Domain
