Read the full article by Erin Rhoda (Bangor Daily News)
“Homeowners, water district operators and plumbers frequently wrap water pipes with Teflon plumber’s tape, which fills the spaces between interlocking pipe threads to seal the pipes and prevent leaks.
But the tape is made with a likely carcinogen called perfluorooctanoic acid, more commonly called PFOA, which is a type of “forever chemical” that has contaminated community water supplies and private wells across Maine and the country.
It’s not known whether the tape is contributing in a major way to the contamination, but some water district operators in Maine are beginning to grow suspicious of it, given their many miles of pipes to maintain and the common use of the tape.
‘All the systems have it. They were put together with it. Most of your shutoffs have Teflon in them. There are possibilities everywhere,’ said Kevin Noyes, the public works director for Patten, which found 6.66 parts per trillion of PFAS, including PFOA, in one of its wells serving the town.
PFAS, or per- and polyfluoroalkyl substances, are a group of thousands of human-made chemicals commonly used in household and industrial products that have been linked to serious illnesses, including kidney cancer.
Maine limits the amount of PFAS in drinking water to 20 parts per trillion. But the federal government issued a far lower, temporary recommendation for some specific chemicals in June. The U.S. Environmental Protection Agency says people’s exposure to PFOA, in particular through drinking water, should not exceed 0.004 parts per trillion over the course of their lifetime to avoid potential health problems.
The Teflon tape has not been tested to determine if it might leach into drinking water at either of these levels, however.
Maine requires materials that contact drinking water to be certified by NSF, an organization that determines if products comply with specific safety standards. NSF requires that certified Teflon tape, which is also called PTFE tape, be tested annually, and it inspects facilities that manufacture the tape each year.
‘Because PTFE materials are manufactured using perfluorooctanoic acid (PFOA) as a process aid … testing of PTFE materials requires analysis for PFOA,’ said Kathryn Foster, senior operations manager for commercial water at NSF.
But when the tape is tested — to determine the quantity of contaminants that seep out when it’s exposed to water — NSF certification requires that the results not exceed an older and less stringent contamination threshold set in 2016 by the EPA: 70 parts PFAS per trillion parts water.
That’s 17,500 times the current, interim recommended level set this summer.
NSF does not require that the results meet the far lower benchmark because the EPA’s latest advisory level is temporary, Foster said. The EPA is expected to soon announce more permanent regulations that the NSF would adopt into its review of product safety, she said.
While the tape is applied to pipe fittings, rather than on the inside of the pipe where water flows, it is possible for the tape to tear and enter the system.
‘It should never be in any direct contact. That’s up to proper installation,’ said Tyler Robinson of Mainely Plumbing and Heating in Gorham.
However, ‘I’m sure there are places where it’s in direct contact. My question is at what level it’s considered an issue,’ said Robinson, who is also president of the Maine Plumbing-Heating-Cooling Contractors Association.
It appears there is no settled answer to his question.
But Jean MacRae, an associate professor of civil and environmental engineering at the University of Maine, has a hunch that it’s unlikely a major source of contamination, especially given all the other potential sources of PFAS now in the environment. The toxic chemicals have been found in rainwater across the world, in addition to household dust.
‘It’s possible’ the tape is contributing to contamination in drinking water, MacRae said, ‘but I would think it’s surely not going to be just that.'” …