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A hundred years ago, we didn't have nonstick pans. We didn't have Teflon. We didn't have

Goretex to make clothes waterproof. Until scientists discovered a special family of chemicals,

PFS, chemicals that repelled stains and dirt and water and oil, that at first

seemed like a miracle. So PFAS stands for per and polyphloral alcohol substances. There are, at last

count, over 10,000 different individual types of PFS. They started to become widespread in industrial use

sometime, I think, in the 1940s. That's Melissa Furlong. She's an assistant professor of

environmental health sciences at the University of Arizona. She's also an environmental epidemiologist.

And because PFAS chemicals have all of these useful properties,

she says we put them in a lot of different things.

Applications that basically need to repel both oil and water. So like if you've got some

stain-resistant furniture or stain-resistant carpet, there's a good chance it was treated with P-FAS.

You might find them on your cooking pans,

raincoats, some pesticides, maybe in your makeup and in you. If you are cooking with a non-stick

teflon pan, right, it's not like all of it is sticking to the pan. Some of the PFS is coming off

onto the food, and then you're exposed that way Some of the PFS is coming off onto the food,

and then you're exposed that way. If the PFS has been applied to your carpet or if it's been

applied to your furniture, then all of that sort of sheds into your environment. And once they get

into our bodies, they're hard to get rid of. Instead of being excreted like normal environmental

toxicants would be they just get recirculated by the body.

Because these chemicals don't break down easily in the environment or in the human body, PFS are known as forever chemicals.

Almost everybody has detectable levels of at least one or two of the different common PFAS species.

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