[http://articles.sfgate.com/2011-02-03/news/27098455_1_perchlorate-drinking-water-jennifer-sass]
Federal regulators took the first step Wednesday in setting a drinking water limit for perchlorate, a noxious component of rocket fuel, flares and fireworks known to hamper thyroid function and hinder brain development in young children.
The Obama administration's announcement comes after two decades of research showing the dangers posed by the ubiquitous chemical and two years after the Bush administration exempted perchlorate from regulation.
"I applaud EPA's decision to regulate perchlorate in drinking water," Sen. Dianne Feinstein, D-Calif., said in a statement. "Americans simply shouldn't have to worry that the water they drink and cook with will make them sick."
Environmental Protection Agency officials said it will take several years to develop the maximum perchlorate level for tap water - long enough for companies to invent new technologies for decontaminating soil and water.
Public health advocates praised the decision but acknowledged the challenges of taking on those who dispersed most of the perchlorate into the environment: the aerospace and chemical industries, NASA and the Department of Defense. For years, efforts to curtail perchlorate and force the costly clean up of polluted sites have met with resistance from manufacturers and the military, which questioned perchlorate's risks.
"We're extremely pleased - (the EPA) has wanted to do this for a long time," said Jennifer Sass, senior scientist with the Natural Resources Defense Council in Washington, D.C. "We hope they can make it final without any more political interference."
California, one of only a few states that already regulate perchlorate, faces a similar battle in its attempts to enact even stricter guidelines.
Under state law, water utilities serving more than 10,000 customers in California are required to test for perchlorate every year. If the chemical is found at or above 6 parts per billion (the equivalent of 1 teaspoon in an Olympic-size pool), the utility is subject to citations or fines. Above 10 times the maximum, the utility must shut down the source of the water supply.
Most perchlorate contamination in California and 44 other states where the compound has been detected stems from military and munitions operations. Known for its combustible nature, the tasteless, odorless perchlorate was historically used in rocket fuel. Today it is still used in air bags and fireworks.
Its disposal wasn't controlled, however, and excess or out-of-date perchlorate was often dumped into unlined ponds. From there it leached into underground aquifers and rivers - including the Colorado River, which provides water for millions of people throughout several states and Southern California.
Because that water irrigates crops and rangeland, perchlorate also taints a variety of foods. A U.S. Food and Drug Administration study of raw and prepared foods in 2006 found elevated perchlorate levels in everything from ice cream and chocolate bars to raisins and spinach.
Its presence in baby cereal and formula - and breast milk - is particularly worrisome given perchlorate's impacts on the thyroid gland. Chronic exposure to perchlorate can dampen the thyroid's ability to absorb iodide and produce hormones. That, in turn, can disrupt metabolic functions in adults and impede physical and mental development in unborn children and infants.
For that reason, California proposed lowering the maximum perchlorate level in drinking water to 1 part per billion last month.
Gina Solomon, senior scientist at the Natural Resources Defense Council in San Francisco, said California's action underscores the need for a federal standard strong enough to protect the most vulnerable populations.
"So many states have no drinking water standard for perchlorate," she said. "If no one is out there testing, they could be exposed to very harmful levels without knowing."
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