Read the full article by Gabrielle Emanuel (WBUR)

“Stacks of boxes line the front hall of Wendy Thomas’ house in Merrimack, New Hampshire, not far from the Massachusetts border. Inside each box are jugs of water that she relies on daily.

Thomas, age 64, uses the bottled water for cooking and drinking because her well water is contaminated with high levels of PFAS…

…After attending a community meeting about PFAS contamination, Thomas learned that unsafe levels of the chemicals had been found in local drinking water. New Hampshire environmental officials largely attributed the pollution to emissions from a factory owned by the company Saint-Gobain. Thomas got her well tested. Then, she got her blood tested…

…’It’s pretty remarkable, in my opinion, that PFAS chemicals can affect so many parts of the body in adverse ways,’ said Patrick Breysse, the former director of the Agency for Toxic Substances and Disease Registry at the CDC, during a presentation to a Massachusetts task force on PFAS. ‘Not many chemicals have such a breadth of effect.’

While some PFAS chemicals are thought to be more harmful than others, researchers are looking into a broad spectrum of potential concerns.

‘I’m not sure I know a tissue or an organ system where effects haven’t been reported,’ said Linda Birnbaum, former director of the National Institute of Environmental Health Sciences and the National Toxicology Program.

What about PFAS give them this remarkable reach inside the body?

Imagine Thomas takes a gulp of her PFAS-laden well water. Or a person catches bass from a contaminated river and fries it up for dinner. Or, perhaps, someone eats a sandwich that’s been wrapped in paper lined with PFAS.

Scientists understand the first thing that happens. The chemicals in the food or water work their way from your mouth to your stomach and into your intestines.

‘And in the small intestine, they’ll basically be completely absorbed into the body,’ said Angela Slitt, a professor at the University of Rhode Island College of Pharmacy. Studies in rodents have shown that PFAS are ‘within a couple of days, 100% absorbed,’ Slitt said, ‘which is not the case for every chemical or drug.’

Once absorbed, scientists compare PFAS to obnoxious house guests: They overstay their welcome, they spread out inside the body, and they impersonate friendlier substances…

…Once PFAS pass through the digestive system, those chemicals find their way to the liver and from there, some get into the bloodstream.

‘They bind to small proteins in our blood,’ said Megan Romano, an epidemiologist at Dartmouth’s Geisel School of Medicine. ‘And what that means is it’s a really excellent delivery system to get all sorts of places in our body.’

PFAS ride along in our blood, reaching all over the body. Researchers believe this is part of the reason why such a wide variety of ailments are associated with PFAS.

Once PFAS are circulating around our bodies, they have the ability to infiltrate a number of organs and body systems.

‘We’re seeing a lot of changes in how things function,’ said Birnbaum.

One of the best understood mechanisms for how PFAS — especially PFOA — interrupt body functions is by impersonating another substance the body has grown to expect and welcome. On a molecular level, PFOA resembles fatty acids, and this allows it to click into certain receptors — called nuclear receptors — in the cell.

Essentially, the molecule fools the cell ‘into thinking it knows the secret handshake, and that’s how it gets in the door,’ Romano said.

This is problematic because fatty acids are essential to the body’s functioning, playing a key role in energy storage, and influencing cell metabolism and how the body responds to hormones.

By impersonating fatty acids, scientists believe PFOA has the potential to alter how our bodies store and use fat. Studies also suggest it can affect hormones like those involved in breastfeeding.

Birnbuam said this is just one of the mechanisms that seems to be at play with PFAS chemicals.

‘There’s evidence that at least 14 different nuclear receptors can be targeted by PFAS,’ she said. ‘It’s complicated, but it explains why you can have different things going on in different tissues.’”…