<http://schema.org/about>
"Water quality in the U.S. is safer than it used to be, but plenty of old &amp; new dangers still lurk beneath the surface. How polluted is U.S. tap water?"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.mnn.com/earth-matters/translating-uncle-sam/stories/how-polluted-is-us-drinking-water?page=1>