PFAS chemicals, what exactly are they?

Adam: The weight of scientific opinion states

That today's non-stick cookware is really quite safe to use, assuming you don't get it way too hot, and so i use non-stick pans a little bit.

But unfortunately, the conversation can't really end there.

Even if the pans are basically safe, the factories that make them are not, nor do they remain safe when we eventually throw them in the trash one day. And that doesn't just go for non-stick pans, it goes for greaseproof fast food wrappers, and a billion other consumer and industrial goods on which modern life is arguably dependent. This topic is a drag, but it is time to talk about PFAS chemicals in our homes and in our environment. Whether or not you avoid certain products, your very existence as a human consumer is contributing to the accumulation of PFAS in our world to the point where exposure is literally unavoidable. And scientists have linked PFAS exposure with elevated risk of cancer, diabetes, high cholesterol, high blood pressure, and therefore cardiovascular disease, liver disease, thyroid disease, asthma, infertility. The good news is increased awareness is leading to increased public pressure on government and industry. For example, McDonald's recently said they're going to change their packaging.

But there's a long way to go, and even if we can motivate change, nobody's even totally sure what the right change is. PFAS stands for, wait for it, per- and poly-fluoroalkyl substances. It's a big category of synthetic chemical compounds that includes Teflon and other non-stick coatings, but it also includes chemicals used in the manufacturer of those coatings and in a million other things. If you've never heard of these compounds, do not feel dumb. At the University of Michigan, you've got one of the global experts on PFAS exposure, Dr. Sung Kyun Park, and Dr. Park: I didn't know PFAS until the 2015. Adam: The guy's an environmental epidemiologist, he did his doctorate at Harvard, and even he didn't really know about PFAS until recently.

That's how new our understanding of this problem really is. But yeah, in 2015, Dr. Park was working on what they call a cohort study. This is where scientists identify some giant group of people, and they follow their health closely, usually for many years. This particular cohort Dr. Park is working on is called SWAN, Study of Women's Health. Across the Nation. Dr.

Park: It was coincidence. Because I wanted to measure many different chemicals, and one of them was just PFAS, even though I didn't know much about PFAS at that time. And then in Michigan, near Grand Rapid, there was a big contamination issue in the Grand. Rapids area. Adam: Yeah, this was a case of groundwater contamination caused by Wolverine, a shoe company. PFAS-based waterproof coatings are used on shoes and all kinds of outerwear. Michigan, with its long and proud industrial history, is just full of PFAS contamination sites that state environmental officials make very easy to see on their website. This one here is not a particularly bad one — it's just one that I could film legally from nearby public parks and streets — the BASF Northworks plant just south of Detroit.

It's a chemical manufacturing plant with known PFAS contamination in the groundwater. For decades now, they've had a deal with the government where they pump up the groundwater, they filter out the bad chemicals, and then they discharge the water back into the Detroit. River.

This is the discharge point, conveniently located

At the end of a public street where.

I'm entitled to stand with a camera. Despite BASF's treatment procedures, they found unacceptably high levels of PFAS coming out of here into the river in 2020. The city of Wyandotte's drinking water intake is literally right downstream from here. The company and the regulators involved all say that they're working on it, subsequent water tests have been okay.

Again, that's just one easily photographed example, but PFAS contamination is all over. Michigan, unfortunately. And there have been a lot of legal cases lately that have been in the news, and so at the. University of Michigan, Dr. Park read about one of those cases, and then he realized something. Dr. Park: I realized that, oh, I measure PFAS in my study. I was able to use blood samples collected back to 1999.

Adam: Here was already sitting on the data. So here we are, 2022, Park et al find a link between elevated PFAS levels in the blood and diabetes — probably type two diabetes, though their methods couldn't distinguish for sure. They had to adjust for demographics and smoking and alcohol and stuff, of course. People usually don't want to live near a chemical plant, so the real estate there is cheaper so poorer people end up living there, and therefore they bear the brunt of the environmental exposure. Poor people are already more likely to have diabetes because they're more likely to smoke and drink a lot and eat a lot of junk, for all kinds of reasons. But you can use math to account for all of that. And when he did, Dr. Park found that elevated PFAS exposure, by itself, that increases risk of developing diabetes about as much as smoking and being overweight increases your risk of getting diabetes, at least in this large cohort of middle aged women.

Why do these chemicals do this? And how can we keep ourselves safe?

Anyway, PFAS chemicals, what exactly are they?

Well, chemists make them in all kinds of forms, but they tend to resemble lipids, fats, like the ones we cook with and eat.

Dr.

Park: Fatty acids have hydrogen in their carbon chain. PFAS, instead of hydrogen, it has fluorine. Adam: Fluorine, the chemical element fluorine. Fluorine forms an incredibly strong bond with carbon, and so you get a compound that is very, very durable across very wide temperature ranges; good for kitchens, good for industry. And because this compound doesn't really react with water or with oil, it just makes an incredibly good protective coating for all kinds of things, not just pans. Dr. Park actually pointed down to his feet at an example. Most carpets installed in public places these days are just covered in PFAS-based anti-stain coatings.

PFAS chemicals are also very effective surfactant, meaning that they lower the surface tension of liquids. And that's very useful when you want to spread a very thin, even layer across something such as when you are chroming metal. Dr. Park: Like in Michigan, in Detroit, there are a lot of these auto supply companies. And then they are using this electro plating, the chrome plating to make the material shiny and then look good. And because this chrome, hexavalent chrome, this is a carcinogen, and so there's workers who are using this material, and they could be exposed to this. And so that's why, to protect workers, companies need to block this vaporization of chromium to the worker, and that's why the surfactants should be used. And then PFAS is the best surfactant.

Adam: That's not a particularly important example in and of itself — I just offer it as an example of how this is bigger than pans. These PFAS chemicals are everywhere and in everything. And that carbon flooring bond is so strong that these chemicals do not biodegrade. That's why people call these forever chemicals. Even when we're not dumping that many of them into our rivers or whatever, they accumulate, most worryingly in drinking water. But research has shown that they bioaccumulate in the foods we eat because PFAS is in the groundwater and in the rainwater. PFAS has also been shown to accumulate in the solid waste they collect out of your sewer system. They recycle that waste as fertilizer, which is good, but then you're putting PFAS into the soil, which is bad.

PFAS chemicals can also hop right into our mouths on our fast food; remember those greaseproof wrappers. They can also get in there from the lipstick that you put on that uses PFAS chemicals as a surfactant. They can also get into your mouth on the dental floss, the kind that glides right between your teeth really nice. That's because it has a non-stick coating on it. And when it gets into your body, it accumulates in your body. Dr. Park: Typically, PFAS stay in the body for several years. It's half life is several years, which means that if you have, let's say, about a 100 exposure level, so then it require about decade to reduce this into 50 and then another decade need for reducing to 25.

That's why if you really want to remove all PFAS out of your body, it takes forever.

Adam: That's happening to all of us

All the time.

But imagine if you live near some point source of environmental contamination, like a factory or a garbage dump or an airport or a military base or a water treatment plant; those aren't very nice places to live usually, so mostly poor people live there. And if you do live there, you're at risk of really high exposure. And why is that so bad? Well, because PFAS chemicals resemble fatty acids on the structural level, and so your cells can actually confuse them for fatty acids and take them in. Dr. Park: These PFAS can interfere with this fatty acid metabolism pathway, and that's why PFAS can impact our metabolism and the immune system and your brain function. And a recent study also suggests that people with high PFAS in their blood, their vaccine efficacy is lower, which means that even though you get vaccinated, you are not able to produce enough antibodies because PFAS interfere, though this vaccine generates this antibody.

That's another big problem. Adam: Why are any of these chemicals legal? Well, some of them aren't anymore. But industry, as we know, it really depends on PFAS chemicals, so if a government says, "Hey, you're not allowed to use PFOA anymore," well, chemical engineers say, "Okay, we'll just use this other PFAS chemical instead.". And then it takes scientists another decade to prove that this new chemical is just as bad as the old one, and then the government has to get it together to ban the new one, and you get a situation they call chemical whack-a-mole. Here in the US, the Environmental Protection Agency, the federal level, they recently put out some stricter guidance on PFOA and PFOS, which are some particularly bad ones that have been around for a while. And then you have individual states like Michigan, also Maine that have been doing some particularly strong state level regulation. But Dr. Park and other experts say it's just really not enough.

This is a situation that really requires strong top down regulation of PFAS chemicals as a class. Not just the individual ones, but as a class. We've got to regulate them all at the same time. In the meantime, sure, you can flex your muscle as a consumer. Dr. Park will tell you not to buy microwave popcorn, for example; the bags are lined in. PFAS chemicals. Then we come back to the pans.

Teflon is a polymer of a particular PFAS chemical, meaning it's that one compound duplicated a bajillion times and all linked together in one big web of the same chemical compound. And so scientists think that if a chunk of Teflon were to come off and you were to swallow it, it probably wouldn't hurt you just because it's too big, it couldn't get into your cells. But through wear, maybe temperature abuse, perhaps individual, little PFAS molecules could break off from here, and if that happened, then you ingested them, then yeah, they could potentially affect you. I don't worry about it too much in terms of my own individual health, but I am worried about the environmental effects of the factories that made my pan and of the dump where my pan will slowly decay for all eternity when I'm done using it. Dr. Park does not use any non-stick cookware. I have one pan that I use as a specialist, pretty much only for eggs and fish. And I'm going to try to make it last.

No dishwasher, no super aggressive cooking. I've treated non-stick pans as nearly disposable in the past, and that's bad. I'm not going to do that anymore. But at the end of the day, this strikes me as a problem that's is just way too big and diffuse to be addressed meaningfully with individual action, so I say call your elected representatives. And maybe all of us just need to start getting ready for the possibility that certain products we have in our life that we consider indispensable, maybe they're not...