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> People cook with teflon-coated pans for the tiny convenience over a nitrided, ceramic, or seasoned cast iron pan. ...which has absolutely nothing to do with

by timr 6mo ago

> People cook with teflon-coated pans for the tiny convenience over a nitrided, ceramic, or seasoned cast iron pan. ...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. Any test that "detects" teflon in the generic category of "PFAS" is a hopelessly flawed test [1]. Unfortunately, a great many of these papers don't make the distinction, whether intentionally or due to incompetence, or simply because it's far easier to do that, and it gets better headlines. [1] Important aside: historically, several of the major manufacturers of teflon had problems with PFOA contamination around the factories due to manufacturing processes. This is unrelated to your personal use of a Teflon pan, and also, the process has been changed. If you want to argue that the new process is also polluting, fine, make that argument -- but don't assert that the use of the final product is itself unsafe.

convolvatron 6mo ago
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.
hvb2 6mo ago
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.
- timr 6mo ago
  > 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.
tristor 6mo ago
> ...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.
- timr 6mo ago
  > 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.
  - tristor 6mo ago
    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.
    - timr 6mo ago
      > 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 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.)
rdn 6mo ago
Teflon is not inert at very high temperatures. Nobody ever overheats a pan?
- timr 6mo ago
  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.

by timr 6mo ago

convolvatron 6mo ago

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.

hvb2 6mo ago

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.

timr 6mo ago
> 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.

tristor 6mo ago

> ...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.

timr 6mo ago
> 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.
- tristor 6mo ago
  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.
  - timr 6mo ago
    > 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 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.)

rdn 6mo ago

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

timr 6mo ago
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.