National Academy of Science report rekindles hot debate over California’s perchlorate contamination
By Michael Collins
The January 10 release of a National Academy of Sciences report on the hazards of the rocket fuel oxidizer perchlorate has the defense and aerospace industry crowing while some environmentalists sing the blues. The report recommends that national drinking water standards be severely relaxed beyond those currently sought by the Environmental Protection Agency, and has reignited debate over the toxic chemical that has permeated the water of 16 million Californians and has threatened drinking supplies in 35 states.
Hanging in the balance are the health of millions of kids and billions of dollars in cleanup costs that the polluters, including the federal departments of Defense and Energy, don’t want to spend on perchlorate-polluted sites across the nation. Adding to the mix, CityBeat has learned that an upcoming study will show that perchlorate has been detected in breast milk not resultant from consuming water contaminated with the chemical, suggesting that the toxin has permeated the food chain to an extent previously unknown.
Over 330 drinking water sources in California have registered concentrations of perchlorate at or above the state’s provisional action-reporting level of 6 parts per billion (ppb). Wells registering at 18 ppb or above are taken out of service for human consumption. Los Angeles County has 138 wells tainted by the toxin. Pasadena has shut down nine drinking water wells due to perchlorate contamination emanating from NASA’s Jet Propulsion Laboratory. The 176-acre lab is in the midst of a $114 million EPA-mandated Superfund cleanup being carried out by the space agency.
Perchlorate interferes with thyroid functioning and is especially dangerous to fetuses, babies, and children. It causes thyroid iodine deficiency that in turn limits the gland’s ability to produce a hormone essential to neurological development. “On average, children of iodine-deficient mothers have 5-to-13 fewer IQ points compared to children of mothers with iodine-sufficient diets,” according to a report issued last week by the Environment California Research and Policy Center. “Reduced thyroid levels in the first few weeks of life for pre-term and low birth-weight babies are associated with increased risk of neurological disorders, including the need for special education by age nine.”
The NAS study recommends a federal limit for perchlorate in drinking water that is 23 times higher than the EPA’s. The 15-member panel concluded that humans could safely consume water with perchlorate levels as high as 0.0007 milligrams per kilogram of body weight, versus the 0.00003 milligrams per kilogram that the EPA currently uses. This so-called “reference dose” determined by the NAS is part of a process that will lead to a nationwide EPA “maximum contaminant level” (MCL).
Naturally, the study has some public health leaders infuriated. “Senator Boxer is not at all pleased with the results of this NAS study,” says David Sandretti, a spokesman for the senator. “She feels that they did not use sound science, that they relied too heavily on the five human tests that they did. In terms of legislation coming down in the next Congress, Sen. Boxer will be reintroducing a ‘Right to Know’ bill for the community so they know what is in their drinking water and that this particular contaminant is present. She’s also going to be introducing legislation to force the EPA to set a date for a MCL standard.”
“Using seven human subjects [in one test] is statistically unstable,” said Dr. Gina Solomon, a senior scientist for the Natural Resources Defense Council (NRDC), an environmental group that strongly criticized the report. “And the NAS did more than just hang its hat on that. They labeled alterations in thyroid levels as not adverse. I use thyroid hormone levels to guide my decisions on whether to treat a patient with medication. When you put all [these] things together, it undermines the results and their recommendations.”
Initial media reports falsely painted an even grimmer picture of the NAS recommendations. The Associated Press, Sacramento Bee, and a slew of other newspapers incorrectly extrapolated the NAS dose and reported that this was equivalent to 23 ppb of perchlorate for drinking water. The final standard, depending on how it is determined, could be much lower than this.
At a January 11 press conference, the NAS panel tried to correct the media’s misinterpretation of the science. “We stopped at a dosage of what we felt would be a safe limit to the amount, whatever the source of perchlorate, that an individual might take in,” said one panel member. “This is 0.0007 milligram per kilogram adjusted for body weight, so if it’s a 3 kilogram baby, you adjust [the amount of perchlorate] down. If it’s an 80 kilogram adult, you adjust it up. It’s based on a per kilogram [measurement]. We did not make the extension into a [ppb] water level. Water level is a matter of policy.”
The NRDC isn’t so sure that the NAS wasn’t trying to set policy favorable to the Bush administration and defense industry. The group subpoenaed communications between the Defense Department, the White House, and a slew of perchlorate polluters including Kerr-McGee Chemical and Lockheed Martin.
The Freedom of Information Act request yielded 30 boxes of heavily redacted e-mails that described such matters as who should be on the NAS panel and how the study should be conducted. These made it clear that industry and the administration were heavily involved in the panel’s inner workings.
Industry observers, however, loved the NAS recommendation. “What’s required now is careful review of the report to fully understand it and determine how the information can benefit the standard-setting process … . 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,” the Council on Water Quality said in a statement lauding the report. Companies including Lockheed Martin and Kerr-McGee Chemical support the group.
But some environmentalists point out the NAS’s suggested standard would still be a big improvement – industry polluters have argued that perchlorate levels of 200 ppb to 350 ppb aren’t harmful. “I think that they’re pretty worried,” said Renee Sharp, a senior analyst for the Environmental Working Group, which praised the report. “Even if you take the study at face value, you still come up with a number that is in the lower parts per billion.”
In the case of a contaminant like perchlorate, where infants are at greatest risk and health consequences can occur from short-term exposure, the EPA has typically used infant weight and ingestion figures when setting a drinking water standard. The federal standard is also affected by how much contamination comes from other sources like food, thus lowering the acceptable amount in water. The California EPA, for example, has determined that perchlorate exposure comes 60 percent from water and 40 percent from food. Figuring that into the weight-based equation, Sharp postulates that the final EPA nationwide standard could be as low as 2.5 ppb. That would be considerably stricter than the current California public health goal of 6 ppb.
A very low perchlorate drinking water standard may be prudent. CityBeat has learned that an upcoming Texas Tech University study will show that perchlorate has been found in breast milk in 11 states, unrelated to drinking water, with some readings as high as 90 ppb. These findings may cause the EPA to look at all sources of perchlorate contamination and to reconsider water standards as they contribute to the production of food and other products nationwide. Senator Dianne Feinstein announced plans in December that she, like Boxer, was introducing legislation that would require a national drinking water standard, and would make polluters responsible for cleanup, saying in a statement, “perchlorate contamination … has entered the food chain. I urge the EPA to take action as soon as possible.”