Second Thoughts on
In Water, How Much Is Too Much?
JENNIFER 8. LEE / NY Times 2mar04
WASHINGTON, March 1 — The Defense Department and the Environmental Protection Agency have squared off in a continuing dispute over the danger from a widespread contaminant of groundwater. Billions of dollars in cleanup costs are at stake.
The contaminant is ammonium perchlorate, an additive that NASA and the Pentagon used for rocket fuel and munitions starting in the 1950's. For disposal, perchlorate was often dissolved in water and poured on the ground because officials did not consider low levels hazardous for people. Perchlorate remains in use and is unregulated.
|Into the Groundwater
Samples taken between 1997 and 2003 that found perchlorate in water and/or soil.
Source: EPA NY Times graphic
Traces of perchlorate have been found in groundwater from California to Maryland. It has been detected in the Colorado River, which provides water to more than 15 million people in the Southwest. In addition, low levels have been found in some lettuce samples and milk around the country, the Food and Drug Administration said. According to Pentagon documents, perchlorate was used in 49 states, with contamination found in 30; Vermont appears to be the sole state where it was not used.
Perchlorate has medical and military uses. It is used to treat Graves' disease, the thyroid disorder, because it suppresses certain hormones.
Officials and scientists dispute whether the amounts in groundwater, usually 4 to 100 parts per billion, are enough to suppress hormone levels in people, which fluctuate slightly anyway.
Scientists at the E.P.A. say that although variations may have few effects on healthy adults, they may hurt the development of fetuses and young children.
A study by the Arizona Department of Health Services found that newborns in Yuma, which obtains its water from the perchlorate-contaminated Colorado River at levels of about five parts per billion, were more likely to have abnormal thyroid functions than the babies who were born in Flagstaff, which does not have such water.
The environmental agency's findings on perchlorate have come under vigorous attack from the Pentagon, the National Aeronautics and Space Administration and the weapons industry.
"We have reviewed the E.P.A. risk assessment, and we think the document is biased, unrealistic and scientifically imbalanced," said Col. Dan Rogers of the Air Force, chief of the environmental law and litigation division at the Pentagon.
Olga M. Dominguez, a deputy assistant administrator at NASA, said, "We do not believe the E.P.A. has used good science."
The Pentagon and the industry say the environmental agency is being overly conservative by not looking at the relevant physiological effects, but instead at a precursor change in the body. Scientists at the agency, say they are considering the most sensitive populations, including fetuses.
Dr. Paul Gilman, assistant administrator for science for the environmental agency, said, "I've good confidence in the work that we have done."
The environmental agency first raised concerns about perchlorate in 1985, when it found high concentrations of chemicals linked to munitions, including perchlorate, in the San Gabriel Valley in California.
The agency found perchlorate contamination ranging from 50 parts per billion to 2,600 parts per billion in its test samples. The tests were never finalized because five of the six control samples, supposed to be perchlorate free, were contaminated.
In one case, the control sample matched the highest contamination in the San Gabriel Valley samples.
In 1993, the Pentagon teamed up with Kerr-McGee, Lockheed Martin and Aerojet, a GenCorp subsidiary, and others to form the Perchlorate Study Group to show that the environmental agency's science was wrong.
In December the group released a study that compared birth records from California from 1983 to 1997 in Redlands, where perchlorate has been detected, with communities in San Bernardino and Riverside counties, where perchlorate has not been detected. The study found that there was no statistically valid difference in levels of thyroid hormone between the groups.
The environmental agency has recommended no more than one part per billion in drinking water, equivalent to a grain of salt in an Olympic-size pool. The Pentagon and the industry are arguing for a human standard of 200 parts per billion.
A standard of 200 parts per billion for people would probably exempt much of the contamination from cleanup, because most such contamination in the United States ranges from 4 to 100 parts per billion.
The environmental agency's recommendation is largely based on a study of rats published in 2001 and financed in part by the Perchlorate Study Group. The study found crude effects on rats' brains from exposure to perchlorate. Parts of the brains were enlarged.
Using a standard safety margin for people, the agency scientists arrived at the 1 part per billion.
In the same study, benign tumors were spotted on two 19-week-old baby rats out of a group of 30 whose mothers had been exposed to high levels of perchlorate. Scientists from the environmental agency say it is unusual to see tumors in baby rats that young, leading them to believe that something must have occurred in the womb.
The Pentagon and the industry say that the study was flawed because just one slice was taken per rat brain and that the baby rats' benign tumors are common enough to be a statistical anomaly.
The level that the Pentagon wants is largely based on a 14-day study that exposed human adults to perchlorate. The Pentagon says the lowest level that showed an effect on the adults translates into 200 parts per billion, though the Centers for Disease Control and Prevention and other agencies using that study arrived at much lower levels.
Ms. Dominguez of NASA said a program to clean up water contaminated with 1 part per billion would cost four times as much as a program for 32 parts per billion, though the differences in health risks are minimal. For the Colorado River alone, the Soil Water Air Protection Enterprise, an environmental consulting firm, estimated that a cleanup mounted to meet the E.P.A. standard would cost $40 billion over 10 years.
Other jurisdictions are establishing safety levels similar to the environmental agency's. California has set an interim safety level of 2 to 6 parts per billion for drinking water, telling water systems not to go higher than 40 parts per billion. The toxicology branch of the disease control centers has a draft risk assessment that puts the safety level for medium-term exposure at three parts per billion.
At least some Pentagon scientists have advocated safety levels similar to the environmental agency's. A study of rats in December 1995 by researchers at the Air Force Institute of Technology found that the level where no negative effects were observed, a standard in toxicology, was "consistent with the assumptions made by the E.P.A."
The deputy for cleanup, munitions and environmental technology at the Pentagon, Lt. Col. Jeff Cornell of the Air Force, said the study was important though "there was not a consensus position developed."
In 2003 the White House referred the debate to the National Academy of Sciences which set up a panel to study the issue. The original chairman of the panel, Dr. Gilbert S. Omenn, a professor at University of Michigan, resigned after he learned that he served on the board of a company that had started developing a technology to clean up perchlorate.
Two scientists on the panel, Dr. Richard Bull, an adjunct professor at Washington State University, and Dr. Charles Capen of Ohio State University, have consulted for Lockheed Martin on perchlorate. The National Academy of Sciences says the previous work does not constitute a conflict of interest. "We eliminate conflicts of interest," said Dr. James J. Reisa, director of environmental studies and toxicology at the academy. "We don't try to eliminate bias. We try to balance it."
Even as the battle continues, the Pentagon has begun exploring legal options to delay or avoid cleanups, in part because states are starting to set their own standards.
In 2003, the Pentagon lobbied Congress for several exemptions from federal environmental laws, including one that covers cleanups of explosive residue at operational sites, a legal description that could be used to include perchlorate. Though the perchlorate exemption was not one of the two exemptions attached to other legislation, the Pentagon has said it will push for it again.
In addition, a perchlorate policy distributed in June by a deputy assistant secretary of defense, John P. Woodley Jr., hints at its next strategy, claiming legal immunity as part of the federal government. The policy said the Pentagon would comply with state legal requirements to respond to perchlorate only "to the extent that Congress has clearly and unambiguously authorized a waiver" of immunity from lawsuits, hinting that the Pentagon will act only if there is a regulation, not just a recommendation.
"They've retreated to the next trench, which is to fight a legal battle either in the courts or in Congress to wipe out their liability," Erik Olson, a lawyer at the Natural Resources Defense Council, said. "It's clear they are not going to voluntarily fix this problem. They are going to be forced to fix it."
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