Stubborn 'forever chemicals' found in 19 Long Island water districts present new drinking supply challenge

Nineteen Long Island water suppliers  have detected unregulated "forever chemicals" that can be difficult to remove, according to a federal database of testing results, providing a look at a new challenge facing the Island’s drinking water.

The health effects of those chemicals, known as "short-chain PFAS," have not yet been extensively studied. But anticipating future regulations, water providers from Bethpage to Hampton Bays are already trying to figure out new methods to remove the stubborn contaminants.

Some water districts have been conducting pilot studies for several years to test different techniques’ effectiveness, trying to determine "what the next round of solutions looks like," said James Neri, a spokesman for the Long Island Water Conference, a trade group for water suppliers.

"Unfortunately we don’t know the silver bullet that takes care of all of them," he said.

Every five years, the federal Environmental Protection Agency requires the country’s water providers to test for about 30 new contaminants — a process the agency calls the Unregulated Contaminant Monitoring Rule.

The samples are drawn from the water after it has been treated to accurately reflect the quality of the water that is ultimately delivered to households. The goal is to gather information about how prevalent they are and whether they should be subject to federal regulations.

Past testing rounds led the EPA in April 2024 to establish limits on six PFAS chemicals in drinking water, individually or in combination.

In 2023, water utilities began to look for 23 short-chain PFAS, cousins to those six regulated PFAS compounds; sampling continues through 2025 and reporting is expected to be completed next year. And while water districts across Long Island have installed filtration systems to remove so-called legacy PFAS, raising water rates to do so, studies have shown that these newer compounds are more difficult to remove.

According to a Newsday analysis of the latest federal data, 77 out of 452 wells that have submitted data so far — or 17% — had these unregulated PFAS in their drinking water above a minimum reporting level in at least one test. The reporting levels seem absurdly small — generally between 2 and 8 parts per trillion, depending on the chemical, though one has a limit of 20 ppt. (One part per trillion is the equivalent of about 30 seconds in a million years, or a single drop in 20 Olympic-sized swimming pools.)

An overwhelming number of tests did not detect contaminants, or detected them at such low levels they didn't have to be reported. Out of 19,181 reported tests for unregulated PFAS, 203 readings were at or above the minimum reporting level, or 1%.

Health effects of short-chain PFAS being studied 

Still, for those areas with relatively high readings, the results could be concerning. There’s ample evidence that the health effects of the legacy PFAS compounds — particularly PFOA and PFOS — can be disproportionately large despite low concentrations. Peer-reviewed scientific studies have found these chemicals accumulate in the body over time, and prolonged exposure is associated with reduced immunity, thyroid disorders, developmental delays in children, kidney and liver disease and cancer, primarily kidney, breast and testicular cancer. 

And there is some emerging evidence that the health risks of short-chain compounds could be similar. A 2021 EPA report notes animal studies show exposure to one of the short-chain compounds results in health effects on "the liver, kidneys, the immune system, development of offspring, and an association with cancer."

Human studies of second-generation PFAS are underway but the long-term effects "are largely still unknown," according to Zeyan Liew, an environmental epidemiologist at Yale University’s School of Public Health. Short-chain PFAS, named because they have fewer carbon atoms linked together, may not remain in the body as long as the long-chains, Liew wrote in an email to Newsday; but he said many other chemicals that leave the body relatively quickly can be harmful nevertheless.

Another reason for concern is because PFAS are so prevalent, "we keep reexposing ourselves to a similar dose day after day," said Erin Bell, an epidemiologist at the University at Albany, who is studying the long-term effects of PFAS-contaminated drinking water in upstate Hoosick Falls and Newburgh.

Environmental health advocates point out water is only one of many sources of contamination, along with things like food packaging and household products, including shampoo and even toilet paper.

"We’re already grossly overexposed," said Scott Faber, senior vice president for government affairs at the Environmental Working Group.

That means it’s important to remove the chemical wherever possible, Faber added. "When we have a lever we can pull, we should pull it as hard as we can."

Eliminating the source of the contamination, experts say, would have tangible benefits for the environment and for human health.

"The good news is, when we reduce our exposure to these chemicals, the amount that is in our bodies will gradually go down," Faber said.

Since the monitoring began in 2023, 36 out of the 44 Long Island water providers required to collect and report samples have done so. Some districts are scheduled to submit results later; small districts and those using other districts’ water are not required to report.

Long Island water districts testing new technologies

Granular activated carbon systems — which work like a giant household filter — can remove PFAS and other contaminants to non-detectable levels, and many Long Island water districts have already installed these on their wells.  Each one costs $1.5 million to $3 million, according to Neri, the water supplier spokesman who's also director of engineering at Melville-based H2M architects + engineers. 

The problem: The short-chain PFAS are not captured as efficiently by these filters.

"There are some small-chain compounds that can pass right through those media," said Michelle Crimi, a professor of environmental and civil engineering at Clarkson University in upstate Potsdam.

Changing the carbon in the vessels more frequently may be one solution, according to Mike Boufis, superintendent of the Bethpage Water District. To efficiently remove long-chain PFAS, the carbon ordinarily needs to be replaced after two or three years. For the short-chains, it might have to be swapped after just a few months.
"That's something that we are exploring now, just to see how quickly it breaks through carbon," Boufis said.

When the Hampton Bays Water District detected a short-chain PFAS at its Plant No. 1 wellfield in 2023, the carbon was replaced, according to James Kappers, the district’s superintendent. EPA data showed no PFAS in the next round of testing.

Boufis predicted some water districts will start to use a different technology: ion exchange resins. Essentially, this method works by running water through a resin or polymer so that harmful ions are "exchanged" with harmless ones.  

Bethpage has resin systems on two wells, installed to remove other contaminants, and is building another. Boufis said the resin technique removes some of the short-chain PFAS "but doesn't remove it 100%.” The district is experimenting "to find a specific resin" that works best.

It’s hard to say how much such a system could cost, according to Neri, because "there are so many variables": Each district and even each well may have a different combination of compounds.

Crimi, who is a member of the New York Drinking Water Quality Council, which sets state standards, said researchers are working to develop additional filtration methods that are "tuned for the smaller-chain compounds."

There’s no consensus yet on what method will be most efficient and cost-effective.

"It's still in the infant stage, to be honest with you," Boufis said.

Uncertain future for 'sins of the past'

Any federal regulation on these newer PFAS would be years away. Advocates are concerned that even the EPA’s present drinking water limits for legacy PFAS — finalized last year but not in effect until 2029 — may not survive the anti-regulatory sentiment in Washington under President Donald Trump.

"Federally, I think we'd all be happy if they did nothing on PFAS," sad Kate Donovan, Northeast director of environmental health at the National Resources Defense Council.

PFAS manufacturers and national water supply trade groups have filed a lawsuit seeking to overturn the EPA’s limits on legacy PFAS, and Trump’s EPA has asked for a pause until early May to decide how or if it will defend the case. Speaking to reporters April 11 in Woodbury, EPA administrator Lee Zeldin said the administration had not made any decisions on whether to maintain the limits set under President Joe Biden.

If the EPA’s 4 parts per trillion standard is eliminated, only New York state’s drinking water standard of 10 ppt for PFOA and PFOS will remain. (A recent report by the Environmental Working Group found an estimated 800,000 Long Islanders had water with PFAS levels that fall between these two standards.)

But environmental health experts have said future PFAS regulations should set limits for all of  them — all at once.

Rather than "regulate one here, one there and going through this really long rulemaking process, just regulate the thousands of toxic chemicals in this class as a class," said Mary Grant, director of the clean water program at the nonprofit Food and Water Watch.

Advocates would also like to see the end of PFAS manufacturing and use.

"We want to stop all PFAS and not just replace one with another as you find out that they're toxic," Grant said. "The best thing to do is just stop it from entering our water in the first place."

That might be something that water suppliers, too, would support.

"We deal with all the sins of the past," Boufis, of the Bethpage Water District said — removing contaminants that have been dumped on the soil and in the water for decades. And yet "these contaminants are still being released into the environment," Boufis said. "If I'm going to have to treat for it, then why should you still allow the pollutant to enter into our water supply?"