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Plenty of people will use those pans and

Overheat them, which means the stuff gets into the air. Many many pet birds have died of this only because they're more susceptible

Use the wrong material in them meaning the start to scratch the Teflon layer.

I'm not saying you cannot use them right, but too many people don't and the product isn't safe when improperly used. This is true for many products but in this case plenty of people aren't aware they're holding it wrong.

> Overheat them, which means the stuff gets into the air. Many many pet birds have died of this only because they're more susceptible

And again, this has nothing to do with PFAS or PFOA. The principle cause is a complete breakdown of teflon into fluorinated small-molecule gases, such as hydrogen fluoride and tetrafluoroethylene. You're literally burning the coating off. It has as much relationship to PFOA as wood smoke has to wood.

> ...which has absolutely nothing to do with the PFOA that you might reasonably be concerned about. Teflon is chemically inert. It's literally used for human body implants. Teflon-coated pans are not your enemy. Fire-fighting foam, on the other hand -- you probably shouldn't bathe in it.

Unfortunately, that is not the case. Yes, Teflon is inert but only when it's not exposed to high temperatures (>350F). When heated, such as in a non-stick pan, Teflon gives off fumes which contain byproducts including breakdowns back into PFAS compounds. So /YES/ the use of the final product (as cookware) /is/ unsafe. NOBODY SHOULD BE USING TEFLON NONSTICK COOKWARE.

> Teflon gives off fumes which contain byproducts including breakdowns back into PFAS compounds.

Completely incorrect. Overheating (aka "burning") completely destroys the molecule, and releases small molecule gases, like hydrogen fluoride. These have no relation to PFAS, they can't turn back into PFAS, and they look nothing like PFAS.

It's like saying that the smoke from burning wood is, in fact, wood.

Teflon does not burn at 350F, it melts between 620F and 662F. At 350F and above, however, it starts off-gassing carbonyl fluoride, carbonyl difluoride, hydrogen fluoride, and various fluorinated alkanes and alkenes. PFAS is a broad term for Per- and polyfluoroalkyl substances which includes several of the compounds that off-gas from overheating Teflon. Off-gassing accelerates into partial decomposition as you cross 500F until it begins melting between 620F and 662F, after 662F you can begin burning Teflon.

As a general rule, if something gives off toxic fumes that kill birds, probably don't use it to cook your food, regardless of what specific compounds its emitting, "canaries in coal mines" and all that.

> At 350F and above, however, it starts off-gassing carbonyl fluoride, carbonyl difluoride, hydrogen fluoride, and various fluorinated alkanes and alkenes

Wrong units. Starts happening at around ~250 C (~480F), not 350F. Completely depolymerizes at around 500C.

https://www.tandfonline.com/doi/abs/10.1080/0002889738506828

> PFAS is a broad term for Per- and polyfluoroalkyl substances which includes several of the compounds that off-gas from overheating Teflon.

Yes, I'm telling you that "PFAS" is a meaningless term that is so broad as to include everything from harmless chemicals (i.e. Teflon) to things that are genuinely toxic (tri-fluoro acetic acid). So using this term as "evidence" of toxicity is just circular logic.

> As a general rule, if something gives off toxic fumes that kill birds, probably don't use it to cook your food, regardless of what specific compounds its emitting, "canaries in coal mines" and all that.

a) It doesn't, unless you specifically overheat it. Don't do that.

b) if that's your standard, you'll definitely want to look at that paper I just linked, because overheating butter in a cast iron pan also kills birds.

I look forward to your campaign against butter. It's certainly more harmful to public health than Teflon!

(To be clear, I am pro-butter and I vote.)

> Wrong units. Starts happening at around ~250 C (~480F), not 350F. Completely depolymerizes at around 500C.

Many places claim 500F is the temperature limit for normal usage of Teflon in a pan, however that's based on the temperature at which it starts degrading, off-gassing begins at lower temperatures. Also, every oil except refined avocado oil will surpass its smoke point at 500F and begin degrading as well, so really you should just be careful with temperature when cooking, regardless of material, but should definitely NOT be using Teflon coated pans.

> Yes, I'm telling you that "PFAS" is a meaningless term that is so broad as to include everything from harmless chemicals (i.e. Teflon) to things that are genuinely toxic (tri-fluoro acetic acid). So using this term as "evidence" of toxicity is just circular logic.

There are no PFAS that are non-toxic. Are you a paid industry shill?

> a) It doesn't, unless you specifically overheat it. Don't do that.

Overheating Teflon pans happens under normal usage simply by exposing it to heat without having food in it, preheating pans is normal behavior when cooking, and is /required/ to reach the Leidenfrost point in other materials (e.g. stainless steel). A material that you have to baby to avoid accidentally releasing toxic fumes /should NOT/ be used for cooking.

> b) if that's your standard, you'll definitely want to look at that paper I just linked, because overheating butter in a cast iron pan also kills birds.

They heated the butter to 500F to produce toxic fumes, which makes sense as you're basically straight up burning it at that point. Butter begins smoking between 310F and 350F depending on milk-fat content, and you should not burn butter. Besides all the other reasons, it tastes and smells horrible. Intentionally burning butter and incidental toxic off-gassing from normal pan preheating are not the same thing.

Teflon is not inert at very high temperatures. Nobody ever overheats a pan?

This has nothing to do with PFAS. When you heat teflon to 500C+, the molecules break down into small molecule fluorinated gases. These molecules are not PFAS, in any way.

the concern is not about immediate effects of using products, but the fact that they are now everywhere in the environment, including water supplies and our own blood streams.