<http://schema.org/about>
"You read that right. Mercury has been found in every fish tested from almost 300 streams over a seven year period. Where is it coming from? Coal."^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.mnn.com/earth-matters/energy/blogs/every-fish-in-america-is-contaminated-with-mercury>