Perchlorate debate is heating up

San Gabriel Valley Tribune, Fred Ortega
Published May 6, 2007

Environmental Protection Agency officials are balking at plans to set a national cleanup standard for perchlorate, a toxic rocket fuel additive that abounds in the nation's drinking-water supply - including the San Gabriel Valley's. The EPA's comments came during a House hearing last week attended by Rep. Hilda Solis, D-El Monte. Solis has proposed H.R. 1747, a bill that would require the EPA to enact a mandatory minimum level of perchlorate in drinking water within 2 1/2 years. The EPA already has a guideline of 24.5 parts per billion as a recommended safe dose for perchlorate, but it has yet to set any mandatory limit for the chemical in drinking water. California is considering setting the limit at six parts per billion, a standard currently being used by many state water agencies. One part per billion is equivalent to about a half-teaspoon of the chemical in an Olympic-size swimming pool. Local water quality officials believe a national standard will help agencies get more money from the federal government for cleanup. However, at last week's hearing, an EPA official said that more study is needed in order to determine whether perchlorate in drinking water should be regulated at the federal level. "We need to determine whether setting a drinking water standard would provide a meaningful opportunity to reduce risk for people served by public water systems," George Gray, assistant administrator for the EPA's Office of Research and Development, told the House Subcommittee on Environment and Hazardous Materials. Gray said that it is still unclear how much perchlorate exposure comes from food, as opposed to water. But Dr. Anila Jacob of the Environmental Working Group said a series of studies by the U.S. Centers for Disease Control and Prevention have put to rest the debate over the health risks of perchlorate. "These studies establish that exposure to perchlorate is widespread and that levels of perchlorate found in people are associated with significant decreases in thyroid hormone levels," said Jacob, senior scientist for the Washington-based environmental group. Jacob noted a recent CDC study found detectable levels of perchlorate in the urine of every one of the 2,820 U.S. residents it tested. The study showed that children had 1.6 times the level of the chemical in their system than adults. In other studies by the CDC and other academic scientists mentioned by Jacob, breast milk samples from around the country were all found to have perchlorate. "The average levels of perchlorate in breast milk in these studies would expose a significant number of breast-fed infants to perchlorate levels above the EPA's recommended dose," she said. Scientists believe perchlorate decreases thyroid hormone levels. Pregnant women with such low levels risk affecting the brain development of their fetuses, Jacobs said. Besides the health benefits of limiting perchlorate nationally, such a move could provide more money for local cleanup efforts, said Gabriel Monares of the San Gabriel Water Quality Authority. "If they do come up with a federal standard, it might result in more money for the state," said Monares, director of resource development for the agency tasked with cleaning up the Valley's water. "It will hopefully create a new pot of money we can go after at the federal level." The bill would also require the Defense Departmentto clean up its sites to the new federal levels. Many of the culprits of perchlorate contamination in the San Gabriel Valley, including Northrop Grumman, are Defense Department contractors. "I would imagine would lead to significant litigation between the contractors and the Defense Department," a Solis official said.