A study released by the American Water Works Association (AWWA) reports that perchlorate has been detected in drinking water in 26 states and Puerto Rico. The study shows that most of the detections were at levels below 12 micrograms per litre (ug/l).
AWWA Deputy Executive Director Tom Curtis explained: “The AWWA occurrence study helps define the scope of perchlorate contamination and its possible effects on drinking water systems and communities. As more sensitive analytical methods are detected, perchlorate detection is likely to increase.”
The US Environmental Protection Agency (EPA) is assessing the need for a drinking water standard for perchlorate, a highly stable chemical compound commonly used for rocket fuel, munitions, fireworks and air-bag inflators that has been found to occur naturally.
Highlights from the occurrence study include several points:
• The majority of detections were not associated with EPA-identified releases of perchlorate.
• Perchlorate was detected in approximately 5% of the nation’s large community water systems.
• Less than 1% of all drinking water systems would be affected if a maximum contaminant level (MCL) of 20 ug/L were established for perchlorate. That would rise to 4% if the MCL were set lower at 2 ug/L.
• The highest density of perchlorate detection was found in Southern California, west central Texas, along the East Coast between New Jersey and Long Island, and in Massachusetts.
A copy of the report can be found on the AWWA website at: www.awwa.org.
