LEILA FADEL, HOST:
For decades, manufacturers have used a class of chemicals called PFAS to make things like nonstick pans and cosmetics. They're also known as forever chemicals because they're practically indestructible, and they're linked to health risks like cancer. Morgan Watkins at Louisville Public Media reports on how that city's water utility investigated a PFAS spike in drinking water.
MORGAN WATKINS, BYLINE: The Ohio River sends billions of gallons of water flowing past Louisville's pumping station every day. The water utility sucks it up and turns it into tap water. Their scientists run a lot of tests, and unlike many smaller utilities across the country, they regularly check for PFAS. One type of PFAS they watch out for is HFPO-DA. It's perhaps better known by a trade name, which is kind of funny - GenX. Last December, Louisville saw a sudden spike in GenX levels, 15 times higher than the month before. Now, that's still pretty low, measured in parts per trillion. Peter Goodmann is the city's water quality director, and he says that's tiny.
PETER GOODMANN: A part per trillion is like one second in 32,800 years. Put your head around that.
WATKINS: But they were curious. Goodmann's team traced the chemical up the Ohio River, past Cincinnati and through Appalachian forests, all the way to a West Virginia factory, 400 miles away. There, the Chemours company uses GenX to make fluoropolymers, a special plastic critical to the semiconductors that power our phones. Goodmann says they calculated that the spike in GenX corresponded to publicly available data from Chemours, data on the chemicals it discharges into the river. In a separate court case between Chemours and an environmental group, Chemours denied their discharge was connected to Louisville's spike. The company says the levels of GenX in the Ohio River are safe. Under current regulations, Chemours can release some chemicals into the Ohio, but it has exceeded the legal limits repeatedly over several years, according to the EPA. Nick Hart works for the Kentucky Waterways Alliance.
NICK HART: Environmental regulatory permitting is a license to pollute. You're permitting someone to put something into the atmosphere, into water, into soil that would not be there otherwise. And so when we talk about the safe, stop using the word safe, right? This is the maximum allowable limit.
WATKINS: It is possible to remove PFAS from drinking water, but Hart says it can get expensive.
HART: It's so much easier, so much less costly to prevent something from getting in there than it is going to be from removing it.
WATKINS: Last year, an environmental group called the West Virginia Rivers Coalition sued Chemours for repeatedly violating its permit. In its responses to the lawsuit, Chemours acknowledges that it is violating its permit, but it says it's working with government regulators on an eventual fix. Still, a federal judge says that's just not fast enough. In August, he ordered Chemours to immediately stop overpolluting. The company quickly filed an appeal. Downstream in Louisville, Goodmann, the city's water quality expert, says he wasn't worried about customer safety, even with last year's spike. That's because risks posed by low PFAS concentrations are measured over a lifetime of exposure, and recent data from Louisville show the PFAS levels in city drinking water fell within planned federal safety limits. Plus, he points out, water is just one way we can be exposed.
GOODMANN: Because you get a lot more of these pollutants from packaging, from pre-fixed food, cake mixes, weird things, you know, popcorn boxes.
WATKINS: But when government regulators issue the next permit for Chemours, Goodmann wants them to set rules that take into account the water treatment plants downstream.
GOODMANN: So what we do is manage risk. And we start that at the river. It sounds weird, but source water protection, keeping the stuff out of the river, is a big deal.
WATKINS: And it'll become a bigger deal in several years when utilities will have to start removing excessive PFAS from their drinking water, regardless of how the chemicals got there. Under the Biden administration, the EPA announced the first-ever federal limits on six types of PFAS in drinking water. But now the Trump administration has announced they'll keep the rules for only two types of PFAS but drop the restrictions on the other four types, which include GenX. And the EPA will give water utilities two extra years to comply until 2031. A federal study estimated about 45% of U.S. tap water contains at least one type of PFAS. If those levels exceed the new limits, many utilities will probably need to invest in technology to remove PFAS.
For NPR, I'm Morgan Watkins in Louisville.
FADEL: This story comes from NPR's partnership with Louisville Public Media and KFF Health News.
(SOUNDBITE OF GORILLAZ SONG, "PLASTIC BEACH (FEAT. MICK JONES AND PAUL SIMONON") Transcript provided by NPR, Copyright NPR.
NPR transcripts are created on a rush deadline by an NPR contractor. This text may not be in its final form and may be updated or revised in the future. Accuracy and availability may vary. The authoritative record of NPR’s programming is the audio record.