NAS perchlorate study ignites dispute over proper drinking water limit

A new study released Jan. 10 by the National Acadamies of Science that suggests 20 ppb may be a more pragmatic limit healthwise for perchlorate in drinking water drew criticism from environmental groups. A component of rocket fuel, munitions and fireworks, perchlorate has been discovered in drinking water supplies in 35 states, tainting supplies of an estimated 11 million people...

WASHINGTON, DC, Jan. 10, 2005 (U.S. Newswire/Ascribe) -- On Monday Jan. 10, the National Research Council of the National Academy of Sciences (NAS) released "Health Implications of Perchlorate Ingestion," a report assessing the health effects of perchlorate, a chemical used in rocket fuel, munitions and fireworks.

Perchlorate has been detected in drinking water supplies across the nation. The U.S. Environmental Protection Agency is currently assessing the need for a standard for allowable amounts of this contaminant in drinking water.

In 2002, agency regulators suggested 1 part per billion (ppb) -- the equivalent of half a teaspoon in an Olympic-size swimming pool -- was an acceptable limit. The just-released NAS study suggests that 20 ppb may be more pragmatic. The panel overseeing the study was immediately assailed by environmental groups as being influenced by the Pentagon, which has argued safety limits could feasibly be set 200 times higher.

Since it's been reported that 11 million people in 35 states drink water tainted with perchlorate (see Perchlorate Incidence Map), the federal government and defense contractors would be under the gun financially at the lower level and the Pentagon has been pushing Congress to limit its exposure to environmental regulations under the Bush Administration.

In addition, many water utilities -- already pressed by other new restrictive regulations in recent years such as for arsenic and radium -- would need to invest more in ways to monitor for and reduce perchlorate levels in their customers' water at a lower level.

Concerning the report, Jack Hoffbuhr, executive director of the American Water Works Association (AWWA), stated "The drinking water community takes nothing more seriously than its responsibility to safeguard the public health. Drinking water professionals have been researching the occurrence of perchlorate in water supplies and continue to pay close attention to relevant health effects research.

"Drinking water professionals have taken many proactive steps to protect against any possible health effects associated with perchlorate. The American Water Works Association (AWWA) is currently sponsoring a national perchlorate occurrence study that should yield useful information for the development of protective federal drinking water regulations. In addition, the independent American Water Works Association Research Foundation (AwwaRF) has conducted several scientific studies on the presence and treatment of perchlorate that will assist utilities in reducing the public's exposure to the substance."

The Council on Water Quality also issued a statement by James Strock, former secretary of the California Environmental Protection Agency (Cal/EPA) and former U.S. EPA chief law enforcement officer, pointing out that perchlorate has been used for 50 years as a medicine to treat thyroid disorders as well:

"It's been critical since the beginning to get the science right on this issue. That's the only way to ensure public health is protected and to ensure public resources aren't unnecessarily diverted from pressing environmental and health needs," Strock said.

The Council on Water Quality is supported by a subset of the member companies of the Perchlorate Study Group, including Aerojet, American Pacific Corp., Kerr-McGee Chemical and Lockheed Martin.

The Environmental Working Group argued the NAS report actually supported a lower safety level for perchlorate since its number was based on an adult male, not a child as is required for health standards. Thus it thought the final limit would still be in the single digits between the EPA and Massachusetts recommendations of 1 ppb and California's at 6 ppb.

"The NAS findings almost certainly mean that when federal health officials write a standard to protect children, we'll see a standard that is even more protective than what the Academy recommends. This is a complete and total rejection of the defense contractors' junk science," said EWG Senior Analyst Renee Sharp.

For an issue backgrounder on perchlorate visit the On Point section at

For additional information, see the following related links:
-- NAS Committee to Assess the Health Implications of Perchlorate Ingestion
-- EPA Perchlorate Fact Sheet
-- California Department of Health Services - Perchlorate
-- Association of California Water Agencies - Perchlorate

About AWWA
Based in Denver, the American Water Works Association is one of the most authoritative resources 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. It 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.


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