DENVER (AP) — Traces of widely used and potentially harmful chemicals have shown up in three drinking water systems in Colorado, prompting officials to shut down three wells and start looking for the source.
Two compounds once used in nonstick cookware coatings, firefighting foam and other materials were detected in utilities serving about 69,000 people in the city of Fountain and an unincorporated community called Security-Widefield, the federal Environmental Protection Agency said. The communities sit side-by-side on the southern edge of Colorado Springs.
State officials say no health problems in Colorado have been linked to the compounds, called PFOS and PFOA.
Officials at the communities' water districts said the chemicals would be far below the maximums suggested by the EPA by the time they arrived at anyone's faucet. All three are conducting additional tests to determine the levels at the faucet.
The findings come amid heightened concern about the safety of drinking water because of the crisis in Flint, Michigan, where the water system contains high lead levels. Authorities say corrosive water released the lead from Flint's pipelines.
Nationwide, PFOS and PFOA were detected in at least 90 public water systems in EPA-required tests between 2013 and 2015, the agency said. Only 17 systems had samples that exceeded the suggested limit for PFOS, and none tested above the suggested maximum for PFOA.
Initial results were released last year, and more are expected this year.
Tests in the Fountain, Security and Widefield water districts found the compounds in about 95 samples. Security had seven samples that were above the EPA's suggested limits for PFOS, and Widefield had one, all from well water. None of the Fountain samples tested higher than the EPA's benchmark.
Neither compound has been found in any other Colorado water system.
Officials with the three districts said they use multiple sources of water, including other wells and an above-ground reservoir, so the chemicals would have been highly diluted before they reached homes.
Still, some residents are concerned.
"I don't know what the short-term effects are or the long-term effects," said Chris Pandolfi, a mechanic who lives in Security-Widefield with his wife and five children. They get their water from the Widefield district.
The family already drinks bottled water, and Pandolfi said he might buy a filtering system for his whole house.
"It's obviously going to take investigation and investment on our part," he said.
PFOS and PFOA — perfluorooctane sulfonate and perfluourooctanoic acid — are human-made and don't occur naturally in the environment. The EPA doesn't regulate them but has them on a list of "emerging contaminants" that could pose a health threat.
Because they're unregulated, there's no mandatory limit on how much can be in water systems, but the EPA issued advisory limits in 2009 suggesting utilities limit PFOS to 0.2 parts per billion and PFOA to 0.4 parts per billion.
The EPA says some studies indicate the two compounds can cause developmental, reproductive and other problems in laboratory animals, and other studies suggest they may have toxic effects in humans.
People can absorb the chemicals through food and water, or inhaling dust or handling materials that carry the compounds, the EPA said.
PFOS hasn't been manufactured in the U.S. since 2002, and production of PFOA is being phased out, the EPA said. But the chemicals are stable and can linger in the environment — including in people and animals — for a long time, said Marco Kaltofen, a research engineer at Worcester Polytechnic Institute.
The Colorado Department of Public Health and Environment is working with the utilities to figure out how the chemicals got into their systems. Possible sources include water leaching out of landfills, effluent from wastewater treatment plants that don't filter for the chemicals and firefighting foam used at military or civilian airports, said Jennifer Field, a professor of environmental and molecular toxicology at Oregon State University.
Ron Falco, manager of the department's Safe Drinking Water Program, said it's too early to speculate on what the source might be.
"It's certainly a challenging investigation," he said.
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