The first nationwide compilation of tap water testing results from drinking water utilities reflects widespread contamination of drinking water with scores of contaminants for which there are no enforceable health standards.

Over a two-year period, analysts at the Environmental Working Group gathered tap water testing data from 42 states to produce a comprehensive picture of water quality. Examples of such contaminants include the gasoline additive MTBE, the rocket fuel component perchlorate, and a variety of industrial solvents. The pollution affects more than 100 million people in 42 states.

States collect water quality testing data from drinking water utilities to fulfill their role as primary enforcement agents, but federal law fails to give the U.S. EPA authority to do the same. The group will present its data to the EPA, state authorities, and water utilities. Individuals can find their own community water system at In addition, tap water contaminants that have been found by water utilities but lack enforceable health standards are also available at this site.