Is it true that using scratched Teflon-coated pans contain carcinogens, and if so, can they be consumed through the food cooked in them?


  • $\begingroup$ I think the moderators didn't like the way you worded your question, but I think its answerable. I tried to edit it, but it was hard to edit and not lose the intent of the question so I will try to answer it... $\endgroup$
    – shigeta
    Commented Aug 30, 2014 at 0:03
  • $\begingroup$ Thank you, eventually you can post your re-phrased question, I'll update. $\endgroup$
    – kenorb
    Commented Aug 30, 2014 at 0:10
  • $\begingroup$ i know what you mean, but the moderators would appreciate it. lmk what you think of my answer :) $\endgroup$
    – shigeta
    Commented Aug 30, 2014 at 0:15
  • 3
    $\begingroup$ You should ask your question on Skeptics.SE. $\endgroup$
    – Remi.b
    Commented Aug 30, 2014 at 4:00
  • 1
    $\begingroup$ Very close to: biology.stackexchange.com/questions/9343/… $\endgroup$ Commented Aug 31, 2014 at 13:04

2 Answers 2


Teflon is a polymer of perfluorooctanoic acid (PFOA) and related compounds. PFOA is thought to be a carcinogen.

I think there's an urban legend that if you really heat teflon up or burn it (it doesn't burn as flouroxides are not stable in air) that you might get some of the constituent chemicals out into the air.

Once the flourocarbons are polymerized into fibers and surface coated a metal pan, they are chemically inert and aren't carcinogenic. Teflon can be made to burn and some noxious fumes produced, but they are not especially carcinogenic.

Even after all this, this paper reviewed PFOA exposure and points out that most people in industrialized countries have some PFOA in their blood and this does not seem to be related to a strong incidence of cancer as the level of exposure is so low.

Flouro-carbon compounds are terribly inert - thats why teflon is so tough. If PFOA is dangerous, then Teflon is > 10 million times less dangerous. If PFOA is dangerous, crossing the street is many more times dangerous.

Even PFOA will be eliminated from Teflon production, supposedly next year (2015).


The question and link imply that if cooking with Teflon generates carcinogens that carcinogens then always lead to cancer. This is not always true. In some cases exposure to carcinogens may signal protective pathways. Oncogenesis and exposure to both genotoxic and non-genotoxic carcinogens are not always positively correlated. Cooking with Teflon influences how you cook, and it's how you cook that has the greatest effect on the levels of carcinogens in food.

Cooked food contains carcinogens in the form of reactive oxygen species. This is related more to the heat its cooked at than the type of cookware used. Carcinogen exposure in the heating of biological material is an interesting subject.

Carcinogens can be classified in 2 categories (1):

  • Genotoxic carcinogens (Reactive Oxygen Species/ROS)
  • Non-genotoxic carcinogens (PFOA is thought to be here)

Genotoxic carcinogens facilitate the formation of cancer through alterations in a cell's DNA.

Non-genotoxic '...carcinogens have no direct interaction with DNA; they are believed to cause tumors by disrupting cellular structures and by changing the rate of either cell proliferation or of processes that increase the risk of genetic error. (1)'

The molecular mechanism most often thought of for cancer formation is genotoxic oncogenesis, damage to DNA. Here, genotoxic oncogenesis often involves a reactive oxygen species (ROS). ROS may generate free radicals which, when reacting with other molecules, generate more free radicals. Another example of a reaction involving free radicals is a fire. Human cells contain genes for antioxidant enzymes, like glutathione and superoxide dismutase, which catalytically converts the free radical superoxide into hydrogen peroxide.

The abundance of ROS in our cells has 2 components:

  • Production of ROS
  • Depletion of ROS by upregulation of antioxidant enzymes

Intracellular levels of ROS positively regulate levels of antioxidant enzymes like glutathione and superoxide dismutase (2). This means that more oxidative stress leades to more protection from ROS by antioxidant enzymes. This is why exercise, while increasing ROS levels, actually protects against them.

ROS are also produced during the cooking of food, especially meat (3). This applies to any type of cookware, any method of heating of any food: protein, carbohydrates, fats.

  • 'For example, it only takes a few hours at 70C to have the same extent of autoxidation which at room temperature requires months (4)'

Intracellular ROS are unavoidable. They are produced by normal metabolism, exercise, cosmic radiation, during the consumption of food. Balancing this are endogenous antioxidant enzymes. The antioxidant power of glutatione exceeds any known nutritional supplement (5).

Exercise is an extremely effective upregulator of antioxidant enzymes, eclipsing any antioxidant supplement or change in cookware. Regular physical activity will most likely be the best prevention one can take against ROS induced genotoxic oncogenesis.

  • 1
    $\begingroup$ This does not answer the question. $\endgroup$
    – MattDMo
    Commented Aug 31, 2014 at 3:28
  • $\begingroup$ Carcinogens in cooked food come mainly from the cooking process not the cookware. $\endgroup$ Commented Aug 31, 2014 at 3:32
  • $\begingroup$ Right. The question is whether the pans themselves contain carcinogens, not whether it's possible to generate carcinogens by cooking foods in the pans. $\endgroup$
    – MattDMo
    Commented Aug 31, 2014 at 3:33
  • $\begingroup$ There is mixed data suggesting PFOA may or may not be genotoxic. If it functions as a ROS, it's important to know that total levels of ROS in the body is not a good indicator of risk for developing cancer. The question implied that carcinogens - > cancer. This is not always true. In some cases a raise in the levels of ROS or other carcinogens may signal protective pathways. Oncogenesis and exposure to both genotoxic and non-genotoxic carcinogens are not always positively correlated. $\endgroup$ Commented Aug 31, 2014 at 3:54

Not the answer you're looking for? Browse other questions tagged .