sdriver writes "San Francisco's bluegills went to work about a month ago, guarding the drinking water of more than 1 million people from substances such as cyanide, diesel fuel, mercury and pesticides. "There's no known manmade sensor that can do the same job as the bluegill." The New York City Department of Environmental Protection reported at least one instance in which the system caught a toxin before it made it into the water supply."
Link To Original Article