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Thornton takes proactive step, warns residents of harmful 'forever chemicals' in its water

Thornton residents can continue drinking water as it meets all federal and state primary drinking water standards, officials say
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Posted at 4:33 PM, Jul 26, 2022

THORNTON, Colo. — The city of Thornton has started sending letters to its residents this week warning them about the level of PFAS chemicals in the drinking water.

PFAS (polyfluoroalkyl and perfluoroalkyl) are also known as "forever chemicals." They are found in everything from firefighting foam to cookware, cosmetics, clothing, food wrappers and more.

Over the years PFAS have been linked to certain health conditions like thyroid disease and even some cancers.

The Environmental Protection Agency had set levels for PFAS in drinking water at 70 parts per trillion. But last month, the EPA issued new health advisory levels, lowering the acceptable levels to .004 parts per trillion for perfluorooctanoic acid (PFOA) and .02 parts per trillion for Perfluorooctane Sulfonate (PFOS).

“We were anticipating some low levels, maybe 10 parts per trillion, is what we were seeing in some of the states who have established that. It really took the whole industry by surprise when they lowered it to .004 and .002,” said Martin Kimmes, the water treatment and quality manager for the city of Thornton.

Thornton takes proactive step, warns residents of harmful 'forever chemicals' in its water

The term PFAS encompasses roughly 5,000 different chemicals. PFOA and PFOS are two of them.

“One part per trillion is the equivalent of one drop of dish detergent in the amount of dish water that would fill a railroad car train ten miles long.

The new health advisory levels are so low there are no instruments that can detect that amount in the water.

Right now, Thornton’s levels coming out of individual plants is 5.4 parts per trillion for PFOA and 7.3 parts per trillion at its water treatment plant. The city doesn’t have instruments sensitive enough to even detect those levels so it sends its water samples to a lab for testing.

Kimmes says the city is trying to be proactive by warning its residents but he suspects many other water utilities across the state and country will need to start warning their customers soon as well.

Frisco has already taken the step of warning residents earlier this month. The mountain town is one of dozens across the state that have tested above the new acceptable EPA limits.

“There are many, many, many more utilities within Colorado and outside of Colorado, this is not even a national problem. This is a global problem,” Kimmes said.

Now, Thornton is working on educating residents about the chemicals and working with the Colorado Department of Public Health and Environment (CDPHE) on a three-phase program to first analyze the different water sources and determine PFAS levels, then work on treatment and mitigation efforts and find the source of the chemicals and finally to engage legislators to come up with laws to remove PFAS from the water cycle.

The city has already turned off one of its water sources, well waters, that have elevated levels of PFOS and PFOA in them. It’s also working on testing out different absorbents to add to the water that can soak up some of the PFAS, but Kimmes warns that will not take the levels down below the EPA standards.

For that, the city will need to add treatment trains to its plants. For now, the city is calling this a concern but not a crisis and reminding people that the EPA guidance is a lifetime health advisory.

“These health advisories aren't from like drinking a liter of water, they're over a lifetime, the 70 year lifetime span,” Kimmes said.

For those who are worried, the city recommends buying an in-home water filtration system that can get rid of PFAS. They can also try to limit their exposure to PFAS in other ways with the kind of products they buy.

Thornton residents and others can continue to drink the water, officials said, as the water is meeting all federal and state primary drinking water standards.

Boiling water will not remove PFAS and can actually concentrate its levels even more in the water. Bottled water is also not necessarily recommended because there is no guarantee PFAS isn’t in that water as well.

People who are pregnant, breastfeeding immune compromised and children under the age of five are most at risk for these chemicals.

To check your county’s PFAS levels, visit this website.