Researchers are looking for 150 private well owners on Cape Cod to volunteer for a study about PFAS chemicals in drinking water.
Exposure to the toxic “forever chemicals” has been associated with decreased vaccine response, testicular and kidney cancer, and more health problems. The study is expected to help establish whether PFAS are reaching private wells by traveling through septic systems.
“Whatever goes into the septic system, there is the possibility that that can be then discharged into a leach field that then trickles down through the sands and gravels in the backyard and recharge the groundwater, which is what a well is also intercepting to bring to your home,” said Alyson McCann, a water quality program coordinator with the University of Rhode Island (URI). McCann spoke during a recent outreach event distributing and collecting water samples outside the Mashpee Public Library.
The study, run by URI’s STEEP (Sources, Transport, Exposure & Effects of PFAS) program, with contributions from the Silent Spring Institute, Harvard T.H. Chan School of Public Health, should also help researchers discover where concentrations of PFAS are the highest in drinking water on the Cape.
“Your public water supplies are regularly tested. They follow a schedule based on regulations. Private wells are not regulated in that way and do not need to be regularly tested,” McCann said. “So what it helps us to do is understand … if there are concerns in any particular area, what might the source of that be? Whether it's septic systems, whether it's the use of firefighting foam in a nearby neighborhood that perhaps contaminated groundwater, or what have you.“
About 15 percent of residents on Cape Cod rely on private wells for drinking water, according to the Cape Cod Commission. Already, STEEP researchers found that in 101 private wells across 12 towns on the Cape, about half had detectable levels of at least one PFAS chemical.
The highest percentage of wells with detectable levels of PFAS were in the Mid Cape, and the lowest percentage were in the Lower Cape. None of the wells exceeded current federal health guidelines for PFAS, but many health experts have called for significantly stricter standards. In the study, 3 percent of the wells had PFAS levels that exceeded a new, stricter state standard that limits PFAS in groundwater to 20 parts per trillion for six chemicals.
The researchers also found that wells with higher levels of nitrate had higher PFAS concentrations; because nitrate is an indicator of septic system impact, this suggests that septic systems could be a source of PFAS in private wells.
To better understand the link between nitrate, PFAS, and septic systems, the researchers are now searching for 150 more volunteers with private wells in towns all over the Cape to fill up bottles from the kitchen sink that will then be tested for nitrate, boron, and 26 kinds of PFAS. Volunteers will get results back for their own homes.
“They will see how they compare to other people in the study to see if their levels are higher than we're seeing in other wells, or to see if it's lower than we're seeing in other wells. It will talk about what kinds of treatment technologies would be useful … and who to contact for more information,” McCann said.
One study volunteer, Sandra Jeffries, has owned a home in Mashpee since 1985, and said she wouldn’t be surprised if her private well had high concentrations of PFAS.
“Honestly, we haven't drank the water in forever. We've always used bottled water,” she said while dropping off three bottles of water from her tap. “And I've always said, ‘Oh, I should have it tested,’ you know, forever ago and a day.”
McCann said STEEP will provide information about how to be protected to well owners with high levels of PFAS in their drinking water.
“There are home treatment systems that can be installed depending on what's in the water,” she said. “Reverse osmosis, for example, is one kind of treatment system that can help to reduce the amount of nitrate in the water and some PFAS’s.”
McCann’s team will be looking for volunteers across the Cape and distributing and collecting water sampling kits in West Barnstable, and either Brewster or Harwich this fall.
Information about how to join the study and limit PFAS exposure in homes can be found at https://web.uri.edu/steep/.
