Perchlorate: It was recently found in Utah milk samples
Salt Lake Tribune, Joe Baird and Judy Fahys
Published January 4, 2006
The state will begin this spring to test groundwater for perchlorate - a rocket fuel chemical - amid growing concern about its presence in drinking water supplies nationwide and its recent discovery in a half-dozen milk samples in Utah.
Larry Lewis, spokesman for the Utah Department of Agriculture and Food, said Tuesday that the department will test for perchlorate in more than 400 water sources in seven counties - Utah, Summit, Wasatch, Carbon, Emery, Grand and San Juan - as part of its annual groundwater sampling, scheduled to run from May to October. Half of the samples will be taken from drinking water wells, one quarter from irrigation wells, 15 percent from springs and 10 percent from wells used for livestock.
"This is a result of ongoing public concern and interest in perchlorate in the environment," Lewis said. "We want to see if it's in the groundwater, find out what's there and act accordingly."
Perchlorate is the explosive component of solid rocket fuel. It is used in munitions, including gunpowder, fireworks and highway flares. Airbags, tanning and leather finishing, rubber, paint and enamel production also rely on perchlorate.
Although the chemical has been in use for decades, there continues to be widespread disagreement about its impact on human health. Some studies suggest that perchlorate even above 100 parts per billion (ppb) poses no danger; others indicate that even tiny concentrations disrupt the thyroids of fetuses and young children, which manage development and the brain.
The Environmental Protection Agency has not established a standard for perchlorate, but has set a "reference dose" for the substance at 24.5 ppb for drinking water. Meanwhile, some states have opted for tougher controls. Massachusetts, for example, has a standard of 1 ppb. California is considering a 6 ppb standard.
The decision to begin perchlorate groundwater testing in Utah was prompted, at least in part, by the results of the state's tests in December 2004 on milk. Contracted to a private lab, DataChem Inc. of Salt Lake City, the tests yielded results ranging from 2.95 to 6.22 ppb, with five of the six samples closer to the higher end.
"It is a very wise move by the state to start looking for perchlorate," said Bill Walker, West Coast vice president of the Environmental Working Group.
"Given what we know about perchlorate in Utah, they may be surprised."
California first found perchlorate in water sources near military contractors and air fields, then launched a statewide program that revealed many water supplies were tainted.
Discoveries of perchlorate in Utah have followed a similar path. The Environmental Protection Agency has identified perchlorate in water supplies at Hill Air Force Base, the site of a Superfund cleanup because of perchlorate; Thiokol, the rocket manufacturer west of Brigham City, and Alliant Techsystems, whose rocket facilities stretch across both West Valley City and Magna.
The discovery of perchlorate in one of its wells has prompted the Magna Water Company to stop production in the well and get rid of the chemical.
"Fortunately, it's been in the 8 to 10 ppb range," said Magna Water Manager Ed Hansen. "But until there is a definite [standard established by EPA], our board felt we needed to isolate it and not allow any of it to go into our system."
Other local water districts are also testing for perchlorate, with encouraging results. Tests by the Jordan Valley Water Conservancy District in 2002 showed no detectable levels in groundwater and surface supplies. The Weber Basin Conservancy District has found perchlorate in a few shallow groundwater sources - in one instance as high as 70 ppb. But it has yet to find any trace in the aquifer it taps for drinking water, even near the Air Force base.
Western water officials have grown increasingly concerned about perchlorate since the May 4, 1988, explosion of a perchlorate manufacturing plant in Henderson, Nev., which left two employees dead and allowed the chemical to begin leaching into Lake Mead. That plant was relocated the following year to a site 15 miles west of Cedar City.
Now called Wecco, short for Western Electro-Chemical Corp., the plant was the site of a 1997 explosion that killed one employee and injured four others.
The state's testing list does not include water supplies near the plant in Iron County.
Walker, of the Environmental Working Group, said omitting the nation's only perchlorate manufacturing plant is surprising.
"That would certainly seem to be a major oversight," he said.
Meanwhile, the state agriculture department wants the milk-drinking public to remain confident.
Lewis says his agency is trying to abide by Food and Drug Administration guidelines. "Their basic recommendation is that those low, low trace amounts appear not to be a problem for consumers, and that people should not alter their diets, avoid foods that contain those extremely low levels of perchlorate."
Perchlorate
What is perchlorate?
A chemical known best as an energy booster for solid rocket and jet fuel and in automotive air bags.
How are people exposed to it?
Tests around the United States have shown perchlorate in varying amounts in groundwater, milk and such irrigated crops as lettuce. There is no question that perchlorate affects the thyroid, but there is heated debate about how much is unsafe. Industries and the Pentagon have attacked animal studies that showed tiny amounts of perchlorate can harm the brains of developing fetuses and infants.
Where can I find out more?
The U.S. Environmental Protection Agency has a Web site with information:
http://www.epa.gov/OGWDW/ccl/perchlorate/ perchlorate.html.
The Environmental Working Group, an advocacy organization, has done five reports on perchlorate contamination that can be found at
http://www.ewg.org. Perchlorate skeptics also have a page:
http://www.tera.org/perchlorate/welcome.htm.
