Drinking water tainted by an ingredient in rocket fuel and explosives is less dangerous than previously thought, and the chemical might not cause brain damage in babies or thyroid illnesses at trace levels, according to a report yesterday by the National Academy of Sciences.
The report said that perchlorate, which has polluted municipal water supplies in Maryland, California and dozens of other states, might be safe at levels at about 20 times the amount suggested by the Environmental Protection Agency in 2002.
The conclusion - if accepted by the EPA and states - could mean a savings of tens of millions of dollars in cleanup costs for defense contractors such as Bethesda-based Lockheed Martin Corp., which has been sued in California for dumping the chemical onto the ground near missile testing sites.
An environmental advocacy group, the Natural Resources Defense Council, charged yesterday that the White House and Pentagon had lobbied behind the scenes to convince the scientific panel to downplay the risks of the chemical.
"This report confirms our worst fears - that the White House and the Defense Department and their contractors were able to unduly influence the academy," said Jennifer Sass, a scientist at the New York-based NRDC. "It's part of a brazen campaign to downplay the dangers of perchlorate."
Officials at the NRDC said that public records recently obtained through a lawsuit showed that the Department of Defense and White House discussed how the scope of the study should be limited and which scientists should sit on the panel.
Some of the studies used by the NAS to reach its conclusions were funded by the defense industry or Pentagon, said the NRDC. And in the end, the 15-member panel had two scientists who had at one time performed work for the defense or perchlorate industries. A third scientist stepped down after being accused of a conflict.
William Colglazier, executive officer of the National Academies of Science, denied that the private, nonprofit organization, whose members are selected by independent academics around the world, was biased or influenced by lobbying.
"We were completely independent," Colglazier said. "The academy has total control over who was appointed, and there were no conflicts of interest."
His organization did confirm that one of the five health studies relied on most heavily by the NAS was funded in part by the Perchlorate Study Group, a defense industry trade association that includes Lockhee Martin.
Gail Rymer, Lockheed Martin spokeswoman, said it's too early to say whether the report will mean lower cleanup costs because the EPA, California and local governments are all free to set tighter limits than recommended by the NAS.
The EPA will review the report and use it to create national drinking water standards.
Lockheed Martin has spent $80 million removing perchlorate and other pollutants from public water supplies in California and will likely spend perhaps $180 million more, Rymer said, depending on the levels required by local governments.
The rocket fuel additive-whose presence in the ecosystem is a legacy of the massive missile buildup during the Cold War - has in recent years been discovered in drinking water used by more than 11 million people in 35 states.
In Maryland, public drinking wells near Aberdeen Proving Ground were temporarily shut down in recent years after testing positive for perchlorate that had seeped from the Army base's testing range.
The EPA suggested in 2002 a maximum safe level of 1 part per billion of perchlorate in drinking water, and Maryland and Massachusetts adopted similar recommendations. Based on a study on rats, the EPA predicted that perchlorate could cause thyroid tumors in humans.
But the NAS panel concluded that the chemical was "unlikely to lead to thyroid tumors in humans." At high enough levels, perchlorate can hurt the thyroid gland's production of hormones, the NAS said. But the panel said there isn't enough evidence to determine whether trace levels of perchlorate will cause brain damage or developmental delays in babies, as some have feared.
What is it? Perchlorate is both a naturally occurring and man-made chemical that is used as the primary ingredient of solid rocket propellant.
What are the health risks? Perchlorate disrupts how the thyroid functions and might lead to tumors of that gland.
Does my water contain perchlorate? Perchlorate has been found in at least 20 states throughout the United States, including in Maryland near Aberdeen Proving Ground.
What does the report mean? If the EPA accepts the scientific panel's recommendations, higher amounts of perchlorate, up to 20 times greater than the current levels, will be allowed in drinking water. Source: EPA