Top 10 Dirtiest U.S. Cities

More stringent regulations and clean air initiatives have helped with the air quality problem the United States faces, but over 175 million people in the U.S.—roughly 58 percent—still suffer from pollution levels that are often dangerous, according to the American Lung Association.

The most common kinds of air pollution fall into two categories: ozone (smog) and particle pollution (soot). Breathing either does not do a body good. Air pollution is a serious health threat that affects all exposed to it. It can lead to large variety of lung ailments and can have a severe impact on cardiovascular health–it speeds up aging and it can be deadly. Some of the biggest sources of air pollution are dirty power plants, old diesel vehicles and heavy equipment, and ocean-going vessels.

Ozone (O3) is a highly reactive gas molecule composed of three oxygen atoms. Although in the upper atmosphere ozone is essential (it protects us from much of the sun’s ultraviolet radiation, thank you ozone)–ozone air pollution at our level is harmful and causes serious health problems by attacking lung tissue and causing inflammation and other damage.

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Disclaimer: The views expressed above are solely those of the author and may not reflect those of
Care2, Inc., its employees or advertisers.

John S.

4:36AM PDT on Apr 30, 2011

Interesting, thought it would be different.

send a green star

A M A.

8:41PM PDT on Apr 29, 2011

And Bill M. is exactly right! Too many cars, poor city planning (suburban sprawl) and poor public transportation are ruining air quality, wasting millions of hours of people's time in interstate gridlock, and uglifying the areas surrounding cities. In America, where the population is nothing compared with places like China, much of this is preventable-- get out of the cars, give people public transport, and stop building all over the place-- concentrate it and make things walkable-- there's a novel idea.

8:38PM PDT on Apr 29, 2011

Gosh, California, that's too bad. Sadly, even these cities would be clean in comparison to many many places in other countries. I don't even want to look at the list of dirtiest cities in China...just remembering them makes me start coughing. :-(

Julie F.

3:00PM PDT on Oct 13, 2010

Sad that the majority of these are in Cali!

Clemente V.

11:09AM PDT on Oct 11, 2010

Yep, I knew Houston was there

Ruth B.

12:29PM PDT on Oct 8, 2010

thank you

jane r.

5:15PM PDT on Oct 6, 2010

Thrilled NYC didn't make the list.

Bill M.

8:39AM PDT on Oct 6, 2010

This happens when you have too many cars, low suburban development density, and not enough transportation alternatives. The irony is that although individual cars produce less pollution than four dedcades ago the increase in the number of vehicles and number of vehicles per capita more than offset improvements in technology.

Christina B.

10:28PM PDT on Oct 5, 2010

I lived in California, I definitely agree. The pollution and air quality are very bad.

James R. S.

9:14AM PDT on Oct 5, 2010

8 out of 10 in California !!! Can something be done about this ???