Last week, the Environmental Working Group (EWG), a nonprofit organization dedicated to protecting the most vulnerable segments of the human population from health problems attributed to a wide array of toxic contaminants, released the results of a three-year investigation of contaminants in municipal water supplies across the U.S. The report analyzes the results of 20 million tap water quality tests performed by water utilities between 2004 and 2009, and finds that such tests detected a total of 316 contaminants in water delivered to the public. Of these contaminants, 202 are "unregulated" (i.e., they are not subject to mandatory safety standards set by the EPA), including the toxic rocket fuel component perchlorate, the industrial solvent acetone, the weed killer metolachlor, the refrigerant Freon, and radon, a highly radioactive gas.
The EWG has also created a searchable database of water test results that allows the public to check out the quality of the water in their community. The database contains information on the contaminants found in 48,000 communities in 45 states. The EWG has also published a chart ranking the quality of water supplies for 100 cities with populations over 250,000 (from best to worst) (Seattle ranks #25, and Portland ranks #59).
The EWG also offers a water filter buying guide for who wish to filter their drinking water.