Perchlorate detected in drinking water in 26 States, AWWA report says

With most detections below 12 ug/L, the U.S. Environmental Protection Agency (EPA) is currently assessing the need for a drinking water standard for perchlorate and the National Academy of Sciences released a health effects report on the contaminant Jan. 11...

DENVER, Feb. 9, 2005 (U.S. Newswire) -- Perchlorate has been detected in drinking water in 26 states and Puerto Rico, according to an occurrence study released today by the American Water Works Association (AWWA).

The study shows that most of the detections were at levels below 12 micrograms per liter, or ug/L (see NOTE 1).

"The AWWA occurrence study helps define the scope of perchlorate contamination and its possible effects on drinking water systems and communities," said AWWA Deputy Executive Director Tom Curtis. "As more sensitive analytical methods are developed, perchlorate detection is likely to increase."

The U.S. Environmental Protection Agency (EPA) is currently assessing the need for a drinking water standard for perchlorate. Perchlorate is a highly stable chemical compound commonly used for rocket fuel, munitions, fireworks and air-bag inflators, and has been found to occur naturally. The National Academy of Sciences (NAS) on Jan.11 released a perchlorate health effects report to inform EPA's actions.

Other highlights from the occurrence study, which was released during a Feb. 9 AWWA Webcast, include:
-- The majority of detections were not associated with EPA-identified releases of perchlorate.
-- Perchlorate was detected in about 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 4 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.
The occurrence of perchlorate in drinking water was analyzed and geographically mapped by compiling data from existing databases, including a national EPA study and studies by the states of Arizona, California, Texas and Massachusetts.

A copy of the report can be found on AWWA's website at (see NOTE 2).

On Point: Perchlorate contains other AWWA resources:

AWWA is the authoritative resource for knowledge, information, and advocacy to improve the quality and supply of drinking water in North America and beyond. AWWA is the largest organization of water professionals in the world. AWWA advances public health, safety and welfare by uniting the efforts of the full spectrum of the drinking water community. Through our collective strength we become better stewards of water for the greatest good of the people and the environment.


NOTE 1: A microgram per liter equates to about one drop in 55,000 gallons.
NOTE 2: The report requires the Adobe Acrobat Reader. The latest version can be downloaded for free at


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