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Apparently Teflon (PTFE) will release toxic fumes when overheated. See this article for a lot of claims without references. You can also kill birds with it.

The claim is that heating Teflon over its melting point of 500 Fahrenheit (260 °C) will release the fumes.

  • Is 500F/260C an achievable temperature on a stove while cooking?
  • Will those fumes stay in the food you're preparing, and are they toxic when ingested?
  • Are there other chemicals being released?

Is using non-stick cookware really dangerous?

w00t
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2 Answers2

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260 degrees is almost unreachable. Water of course boils at 100 degrees, keeping the temperature down. When cooking with fats and oils, you always keep the temperature below the smoke point. Those are generally below 260 degrees, except for some rare oils.

Even then, you rarely heat oil just for the sake of it: there's usually something in the oil, and that will burn. This will produce acrylamide (a cancer-causing chemical) at temperatures well below 260 degrees.

The real risk is an empty pan. Heating that will cause a quick rise in temperature, as there's nothing to keep the inside cool.

For toxicity, I'll assume human toxicity. I don't think the danger to birds is disputed. As is usual with toxicity, the important part is the dose. Here we see a bit of a problem with the EWG site linked in the quqestion: they're using scare tactics. Their standard for doses is "have been detected". Not medical risk. The FDA continues to list Teflon as "safe for cooking"

As for "other chemicals being released", it's hard to measure this. Cooking releases hundreds, if not thousands of different chemicals. Many of them you can smell; you'd call them "flavors" or "aroma's". Non-stick pans are hardly unique in this respect.

MSalters
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  • +1. Small caveat: Pizza needs to be prepared at higher temperatures for crispness. But most household ovens don’t even reach those temperatures so this is only relevant when working with a stone oven. – Konrad Rudolph Sep 20 '11 at 12:15
  • Hmmm... thinking about this, when you prepare e.g. a steak in a non-stick pan the cooking fat won't coat the entire pan, it will coalesce, leaving areas of the pan uncovered. A methane flame burns at >900C so following your reasoning that would mean areas of the pan could overheat and release the gases. So then Teflon would only be safe for your parrot if you use enough fat to cover the entire pan surface. – w00t Sep 20 '11 at 20:16
  • @Konrad: although you don't generally cook pizza in a teflon pan... do you? – nico Sep 20 '11 at 20:29
  • @nico the only pizza pan I have is a really thin teflon coated plate with holes in it... something like [this](http://www.amazon.com/gp/product/B0000D8CAO) – w00t Sep 20 '11 at 21:14
  • @w00t: ok... never saw one of those. Anyway problem does not exist as your house oven won't go normally go at more then 250°C. And if you're using a wood-fired oven, which goes above said temperature, you're just cooking the pizza on the stone I would hope! – nico Sep 20 '11 at 21:19
  • not just is it almost impossible to reach the temperatures required in a home environment, the amounts released were they reached are miniscule unless maybe there was prior damage to the coating. – jwenting Sep 21 '11 at 14:06
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    It is quite common for Ovens in the US to reach 500-600 for broiling. Not to mention even some electric burners can reach 1000f well above 260C. – Chad Sep 21 '11 at 15:32
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    @w00t - Re: Cooking Steaks: Most teflon pans I have seen are aluminium. The thermal conductivity of aluminium is quite high. Therefore, the ability for the pan to form "hot spots" on areas without food cooling them low. The uncovered areas will be cooled by nearby cooled areas. As an example, heat a aluminium pan, and then dunk one edge in water. The whole pan will cool quite rapidly. – Fake Name Sep 21 '11 at 21:43
  • Slightly worried here, as I dry cook steak sometimes, with no oil and there is a curious smell from the non stick pans. Is this dangerous? – Hairy Sep 22 '11 at 07:23
  • @Hairy: Don't hold your parrot over it. If it smells like burning plastic, it is probably polymer fumes, which are generally documented to induce fever-like symptoms in high enough doses. So far, no evidence shown here points to it being dangerous for humans at cooking-released doses. – w00t Sep 23 '11 at 09:36
  • I'm accepting this as the answer. It's not completely conclusive but it seems that when taking just a little care about overheating, covering as much surface as possible with food and using thicker pans (for better heat distribution), there is really nothing to worry about. – w00t Sep 23 '11 at 09:39
  • What about the teflon flakes that peels off with time? Couldn't it be any health issues if it ends up in the cooked food? – Stefan Rådström Jul 19 '12 at 20:37
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    @StefanRådström: Since it's non-stick, it doesn't tend to stick to your intestines either. It's also inert, meaning that it doesn't break down into chemicals which could enter your blood. Hence, there's only one way out of your body for them. – MSalters Jul 20 '12 at 08:28
  • @KonradRudolph: Most for preparing pizza at home recipes say 190-225°C, depending on pizza type. As for stone oven, there you just put pizza directly on the stone. – vartec Jul 23 '12 at 15:45
  • @vartec I wasn’t talking about frozen pizza. For fresh dough, the hotter, the better. – Konrad Rudolph Jul 23 '12 at 16:08
  • @KonradRudolph: I wasn't either. For frozen ones it's 180°C. But you're right. In stone oven it's more like 400°C. – vartec Jul 23 '12 at 16:14
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Natural gas burns at ~2770 C so if you are heating a skillet coated in teflon over a natural gas burner you have the potential to achieve spot temps over 260 C. So It would appear the the answer to your first question is yes 260C is achievable on a common household stove. Even DuPont the maker of teflon agrees that it is possible and should be avoided.

There has been a link to reproductive problems with gases released by Teflon pans

As for birds DuPont recognizes that the gases pose a danger to them.

There are nonstick pans that are non-PTFE that would not have these problems.

Chad
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  • You're seriously linking to anti-fluoridation stuff? That guy is a surgeon, btw, not a dentist or statistician. – dtanders Sep 21 '11 at 15:57
  • @dtanders - [Ad-Hominim](http://www.nizkor.org/features/fallacies/ad-hominem.html) attack on the author aside... The op wants information on the gases released and if they are a health risk and that document contained valid information reguardless of its stance on the subject. – Chad Sep 21 '11 at 16:12
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    Fluorine gas and fluoride ions are two very different compounds, despite being the same chemical element, and very likely irrelevant as you haven't shown that those are degradation products of PTFE. The chemicals released from overheated PTFE are likely a very complicated mixture of organofluorines. Your link about reproductive problems is about PFOA which is used in PTFE production, but you haven't shown that it is released from overheated PTFE. And as always, the dose makes the poison and you don't have any data on the actual amounts of released chemicals. – Mad Scientist Sep 21 '11 at 16:51
  • @Chad - pointing out that the author of the quackery you linked to seems to have no relevant experience in the field he's claiming to be an authority in is not an Ad-Hom because not everyone with an MD after their name is an equally reliable or believable source of information on every aspect of health. [Anyway, here are some more reliable links regarding water fluoridation](http://www.google.com/cse?cx=013733630485239034658%3A5df9dg8f9gc&q=fluoridation&sa=Search&cof=FORID%3A0&siteurl=www.quackwatch.org%2F00AboutQuackwatch%2Fgsearch.html) – dtanders Sep 21 '11 at 17:26
  • @dtanders did you read any of it or just come to the conclusion that the entire thing was quackery. And just because he is a surgeon does not mean he has no experience in the field, nor does being a statistician or dentist infer that they would. A dentist who never does any research and just has a family practice would be less qualified than a researcher who has actually done the research. So your attack is Ad-Hominim. – Chad Sep 21 '11 at 17:46
  • @fabian Are you saying they are not? Florine Gas binds with other molecules in foods and becomes floride solids. Personally I have teflon pans and I have birds. I keep my birds away from my kitchen and turn on the exhaust fan. I am not afraid of them but I am aware of the dangers. I do not think that florides are dangerous in the quantities we consume but the OP asked for research to show it was. I provided that with out any personal stake. You can melt teflon on your stove. The gases can be dangerous. They can bind with food into a form that may or maynot be safe. – Chad Sep 21 '11 at 17:52
  • @Chad - Yep, I read it and it's scaremongering garbage from a guy who probably hopes you'll believe anything he says because it validates your preexisting worldview and he has an MD after his name – dtanders Sep 21 '11 at 17:57
  • There is no evidence that fluorine gas is produced by overheating PTFE, and even if it was produced, fluorine gas reacts violently with nearly everything, so nothing of it would reach you anyway, only its reaction products. Mentioning the dangers of fluorine is extremely misleading therefore. There are probably dozens of different substances created by overheating PTFE, the exact nature of those and especially the concentrations are very important, just writing about fluorine and fluorides is very misleading. – Mad Scientist Sep 21 '11 at 18:12
  • The climate change stuff is off-topic here, I deleted the comments. – Mad Scientist Sep 21 '11 at 18:20
  • @fabian but not the attack on my world view ... way to be consistant. – Chad Sep 22 '11 at 16:32
  • I did not realize there was a question about the flourine gas. It is cited in the refrerences of the wiki from the OP if anyone had bothered to read. And yes the florine most commonly is in florides which are also given off. – Chad Sep 22 '11 at 16:35
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    @Chad It's spelled fluoride, and you're still mixing up very different chemicals, nobody is talking about fluorine or fluorides, the compounds that are created by overheating PTFE are mostly organofluorines or fluorocarbon compounds. You're jumping to conclusions based on a fundamental misunderstanding of chemistry, pretty much everything you state in the post is either not directly relevant to teflon cookware or based on extremely dubious science (the anti-fluoridation stuff). – Mad Scientist Sep 22 '11 at 17:04