STOW — The water fountains have been turned off, wrapped in plastic, or fitted with a device to prevent students from using them. Much of the food preparation has moved off campus, and a water jug sits in the kitchen sink, replacing the faucet. The bathrooms are covered with signs that warn students in bold, red letters: “DO NOT DRINK FROM THE SINK.”
Just before school started last month, district officials here alerted parents and staff about a “water situation” at the Center School, and the nearby Hale Middle School. A new, targeted testing program by the state Department of Environmental Protection had found that the water at both schools contained significant amounts of per- and polyfluoroalkyl chemicals known as PFAS, which have been linked to kidney cancer, low infant birth weights, and a range of other diseases.
The Nashoba Regional School District was the first public water system to be tested under the new program, suggesting that the toxic chemicals may be far more prevalent in drinking water than has been understood.
“I would hazard a guess that virtually every town in Massachusetts has detectable levels, some of them higher than this,” said Kyla Bennett, a former scientist at the US Environmental Protection Agency who now serves as director of Public Employees for Environmental Responsibility in New England, an advocacy group.
Concerns about PFAS, often called “forever chemicals” because they never fully degrade, have mounted in recent years, and regulators are beginning to take action. Developed in the 1940s, the chemicals have been used in products such as flame retardants, nonstick pans, pizza boxes, clothing, and furniture.
Water at the two public schools, which draw from their own wells, contained concentrations of the chemicals below current federal and state guidelines but above forthcoming regulations, which are based on more recent assessments of their risk.
In a letter to the community, Brooke Clenchy, the district’s superintendent, said the schools were turning off the drinking water and bringing in bottled water “out of an abundance of caution.”
“Where we see opportunities to be proactive, rather than reactive, to a situation, we make every effort to do so,” she wrote. The letter did not mention the health risks of exposure.
The findings confirmed tests the district had conducted earlier in the summer, after environmental officials urged public water systems throughout the state to test their water for PFAS. Only larger water systems, those serving more than 10,000 people, are required by the federal government to test for the chemicals.
More than half of the state’s municipalities have not had their drinking water tested for the chemicals, according to data from the state Department of Environmental Protection. Many more private wells have gone unsampled.
While the findings at the schools in Stow have alarmed some parents, district officials say they don’t know whether to be concerned.
“It’s really hard to grapple with something that’s happening in real time like this,” Clenchy said in an interview at the Center School.
EPA officials have said that by year’s end they will release comprehensive national drinking-water limits for two of the most prevalent PFAS chemicals. The agency currently maintains a health advisory that recommends municipalities alert the public if the two chemicals reach 70 parts per trillion. Massachusetts uses the same level for five of the most common PFAS chemicals.
Recent studies suggest that the maximum levels allowed in drinking water should be far lower than the current advisory. A draft report by the federal Department of Health and Human Services — which the EPA last year sought to prevent from being published — said the chemicals could be harmful at one-sixth the levels the agency now considers safe.
Some states already have set stricter standards. New Hampshire recently set a limit of 11 parts per trillion for one of the more prevalent chemicals, while officials in New Jersey recently set similarly low standards for other common compounds.
Some recent studies have recommended that children not consume water with concentrations of the chemicals greater than 1 part per trillion, calling the health risks “greatly underestimated.”
One part per trillion is about as much as a grain of sand in an Olympic-size swimming pool.
Officials in Massachusetts are considering adopting a standard similar to one recently enacted in Vermont, advising residents to avoid drinking water if the concentration of six of the chemicals cumulatively reaches 20 parts per trillion.
Beyond Stow, the chemicals have been found in the drinking water of seven municipalities. In four — Ayer, Barnstable, Mashpee, and Westfield — the concentrations exceed the EPA’s current standards. The chemicals were found in lower amounts in Danvers, Hudson, and one section of Harvard.
The Department of Environmental Protection recently tested in Carver and Blackstone and announced plans recently to ask the Legislature for $8.4 million to expand PFAS testing of public water systems and $50 million to back low- or no-interest loans to help municipalities install new filtration systems.
“As part of MassDEP’s continual review of emerging scientific data for environmental and water quality standards, the department has issued draft rules for future site cleanups with ground water impacted by PFAS and continues to work closely with public water suppliers to address and resolve known or suspected PFAS contamination,” said Ed Coletta, a DEP spokesman
The state decided to test the water in Stow because of the schools’ proximity to the former Fort Devens-Sudbury Training Annex, he said. Testing of nearly 2,700 ground water wells on or around military installations in recent years has found that 60 percent contained high levels of the chemicals, according to the Department of Defense. Many were probably contaminated by a firefighting foam used for years by the military.
It was not clear that the training facility in Sudbury is responsible for the contaminated water at the schools, which together have more than 800 students. An average of the two tests showed the wells at the Hale School had a cumulative total of more than 38 parts per trillion of five of the chemicals; the Center School had more than 24 parts per trillion.
Because of the testing methods used, the actual concentrations are likely to be higher, specialists said. The tests didn’t measure many other PFAS chemicals, and the methods used couldn’t detect lower amounts of those that were tested for, in some cases below 4 parts per trillion.
“This is just the tip of the iceberg,” Bennett said. “There are probably many, many more PFAS chemicals in that water, particularly the more ubiquitous short-chain PFAS, that they did not test for.”
She and other environmental advocates have accused federal and state officials of acting too slowly to address the risks.
“I would suggest, based on these results, that parents be proactive in requesting testing in other schools,” said Elsie M. Sunderland, a professor of environmental chemistry at Harvard University.
As she picked up her second-grader at the Center School one recent afternoon, Amy Flynn said she worried that her children — she also has a fifth-grader at the school — had too much exposure to the water.
“It’s definitely concerning,” she said.
District officials said they’re seeking a permanent fix that would filter the chemicals from the schools’ water. But they couldn’t say how long that would take, or how much it would cost.
With three children in district schools, Ilana Gordon-Brown said the results were unsettling.
She’s now worried about her water at home, which is closer to the training facility in Sudbury.
“We need to know what we’re drinking,” she said.