11. Sacramento-Roseville, CA
Besides the measuring of the high ozone days, this metropolitan is 14th for 24-hour particle pollution out of 186 metropolitan areas and 39th for annual particle pollution out of a total of 184 metropolitan areas. In addition, a lot of people have the problem with breathing. More than 150,000 are suffering from adult asthma, and 1,101 have lung cancer.
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