National Academy of Sciences report reignites debate on danger of perchlorate
By Michael Collins
Pasadena Weekly – January 20, 2005
The Jan. 10 release of the National Academy of Sciences report on the hazards of perchlorate recommends national drinking water standards be radically more lax than those that the Environmental Protection Agency currently strives for, reigniting the debate over the toxic rocket fuel oxidizer that has permeated the water of 16 million Californians and threatened drinking supplies in 35 states.
What hangs in the balance is the health of millions of kids and billions of dollars in cleanup costs that the polluters, including the Departments of Defense and Energy, don’t want to spend on perchlorate-polluted sites across the nation. Adding to the mix, the Weekly has learned that an upcoming study will show that perchlorate has been detected in breast milk that is not resultant from consuming water contaminated with the chemical, suggesting that the toxin has permeated the food chain to an extent previously unknown.
More than 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 in 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 10 of its 16 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 EPA-mandated Superfund cleanup being carried out by the space agency.
Following stricter guidelines than those set by the state, Pasadena shuts down wells when perchlorate levels measure above 6 ppb, which is the state’s current public health goal for consumption and the number on which action-reporting levels are based, said Pasadena Water and Power General Manager Phyllis Currie. If a well reaches the 6 ppb mark, state law would require Pasadena to notify residents of perchlorate levels in their drinking water. Because Pasadena instead stops serving water at that level of contamination, Currie said the National Academy of Sciences report will have no immediate effect on the city. However, “We would like to see some clarity brought to this issue,” she said of scientific debate over perchlorate dangers.
In August Pasadena shut down two water wells, one of them located near Villa Parke and another near the intersection of North Allen Avenue and Monte Vista Street, when perchlorate levels jumped to as high as 9.8 ppb, said Shan Kwan, director of Pasadena Water and Power’s Water Division. In response to those closures and fearing nearby East Pasadena wells could soon become contaminated, Pasadena City Council members moved in December to start drawing up treatment plans for polluted wells near Villa Parke. Threatened wells are located within as little as a mile or two from the now-shuttered Monte Vista Street well, said Kwan, and some of them are already showing perchlorate readings of 1 to 2 ppb.
There’s good reason to be fearful of perchlorate contamination. The chemical interferes with how the thyroid functions 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 that the federal government allow 23 times the amount of perchlorate be allowed in drinking water than the federal EPA does. The 15-member panel concluded that humans could safely consume water with as high as .0007 milligrams per kilogram of body weight, versus the .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 environmental leaders infuriated. “Sen. [Barbara] Boxer is not at all pleased with the results of this NAS study,” said 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 certain for an 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. Associated Press, the Sacramento Bee and a slew of other newspapers, incorrectly extrapolated the NAS dose and came up with a tentative EPA equivalent amount of 23 ppb of perchlorate for drinking water.
At a Jan. 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 .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 perchlorate-producing and -using industries. 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 emails that described such matters as who should be on the NAS panel and what they should concentrate on.
Naturally, the industry 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 don’t believe that the polluters are too thrilled – the industry has 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 that 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.”
And Sharp may be right. In the case of a contaminant like perchlorate, where infants are at greatest threat 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. And according to the agency, establishing a drinking water standard “typically involves the use of a relative source contribution factor to account for non-water sources of exposures.”
The California EPA 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 6 ppb California public health goal.
A very low perchlorate drinking water standard may be prudent. The Weekly 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! This alarming new information should grab the attention of the EPA when it makes its final determination for this toxic chemical that threatens the very minds and physical well-being of America’s youth.