Collinsville has reversed its previous guidance that the city’s drinking water is safe after new tests revealed rising levels of so-called “forever chemicals” in groundwater and treated water, which exceed federal limits.
The city is now recommending that residents filter city tap water before drinking or cooking with it, contrary to assurances it gave just five months ago.
Exposure to the contaminants known as PFAS has been linked to certain types of cancer, fertility and child development issues and other health problems.
PFAS is shorthand for perfluoroalkyl and polyfluoroalkyl substances. The synthetic chemicals have been used for decades to make products that repel oil and water such as nonstick cookware, waterproof clothing, stain resistant furniture, food packaging and cosmetics, as well as firefighting foams.
They are called forever chemicals because they break down very slowly and build up over time — including in the human body when people ingest them. PFAS don’t have any taste, color or odor.
The U.S. Environmental Protection Agency says people face health risks with any level of exposure to two PFAS in particular. And Collinsville saw elevated levels of one of them in its new tests: perfluorooctanoic acid, or PFOA.
Under new EPA regulations, the legal limit for PFOA in drinking water is 4 parts per trillion, a standard set after considering costs and available water treatment technology. However, the agency’s public health goal is to have no amount of PFOA in drinking water.
Treated drinking water samples from May 2 and June 26 in Collinsville detected PFOA at 11 parts per trillion and 17 parts per trillion, respectively.
Chief water plant operator Michael Crawford told the City Council on Tuesday night that a new lab tested the sample from May. Officials sent another sample from June to a lab the city has worked with in the past, which confirmed the elevated PFOA levels.
Crawford couldn’t immediately be reached Wednesday for further comment.
Before the 2025 test results, the city had said as recently as April that the water was safe to drink and filtering was not needed.
The city’s highest PFAS results since 2020 were PFOA readings of 44 parts per trillion in untreated well water from two wells in 2021 and 2023. It stopped using one of those wells in September 2024 after repeatedly high results there even after treatment.
Collinsville is in the early stages of a multiyear process to update its water treatment equipment to remove more PFAS from treated water that goes into citizens’ homes by 2029.
“This is as fast as it possibly can happen, since this is a large project,” the city stated in an updated FAQ on its website.
2029 is also when oversight agencies will begin enforcing the EPA’s limits on PFAS in drinking water with violations and fines.
Which water filters work on PFAS?
The EPA says certain types of home water filter systems can reduce PFAS, including:
- Granular activated carbon (GAC), which traps chemicals as water passes through it.
- Reverse osmosis (RO) systems, which force water through a thin barrier that separates chemicals from the water.
- Ion exchange resins, which are tiny beads that act like powerful magnets to attract and hold the contaminated materials from passing through the water system.
The agency advises consumers to check product packaging for faucet filters, filtering pitchers and under-the-sink devices for “NSF/ANSI 53” or “NSF/ANSI 58,” which means it has been certified to reduce PFAS by an independent entity.
Editor's note: This story was originally published by the Belleville News-Democrat. Lexi Cortes is a reporter for the BND, a news partner of St. Louis Public Radio.
