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"The State of the Air 2010 shows that the air quality in many places has improved, but that more than 175 million people \u2014 roughly 58 percent \u2014 live in dange"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.mnn.com/health/healthy-spaces/photos/7-us-cities-with-the-worst-air-pollution/the-air-we-breath>