Teflon: Health and Safety

[R Washburn]

Good Teflon pans can be very good for certain things, but by and large, I've never had the overwhelming need for them. Perhaps I've never learned to use them correctly because I've bought cheap ones that loose their magic all too quickly. They're certainly not needed for eggs. A cast iron skillet does quite well for fried eggs and omelets don't stick to my aluminum pan. Naturally both are very well seasoned. Then again we might all consider the risk of aluminum pans. Come to think of it, if you're not in fear of everything you eat, you probably haven't read enough on the subject.

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With Teflon we do have a real risk, unlike the "imagined" risks of rBGH or irradiated beef. Even if I was not a parrot owner I would refrain from heating any teflon in my home, because of the very real health risks associated with it. "Teflon Flu" is enough to put me off the pans.

I handle enough toxins, carcinogens and radioactive isotopes in my day job.

Edited January 28, 2006 by R Washburn (log)

[Patrick S]

. . . . The bad news is that it's present in ALL non-stick cookware currently in use.

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I'm pretty sure this is not true. According to the EPA release, PFOA "is an essential processing aid in the manufacture of fluoropolymers, which are used in the manufacture of a wide range of non-stick and stain-resistant surfaces and products . . ." and "may also be produced by the breakdown of fluorotelomers, which are used to impart water, stain, and grease resistance to carpets, paper and textile." It's not generally present in cookware as purchased. According to the Dupont web site: "A published, peer-reviewed study (April 2005) in Environmental Science & Technology found no PFOA in Teflon cookware. No PFOA was detected even when the cookware was scratched with a knife."

Dupont does qualify: ". . . according to a recently published study conducted by researchers at the U.S. Food & Drug Administration (FDA), PFOA was detected in minute quantities in cookware using extreme and abusive test methods--methods that do not reflect what happens when consumers use cookware."

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I want to underline that last point: the article they are referring to, recently published in Food Additives and Contaminants, did not state that PFOA migrates from PTFE during normal use. In fact, they clearly pointed out that in previous studies designed to simulate real-world conditions, the migration of PFOA into food simulant was either nonexistent, or so low that it was below the detection limit of currently available analytic tools. What the most recent study did was use a grinder to grind off all the PTFE coating into a powder, and then heat the powder in solvents like hexane for an extended period of time. They proved that under those conditions, you can extract an extremely small amount of PFOA, and therefore there is an extremely small amount of PFOA in PTFE cookware, on the order of a few ng per kg of PTFE. Begley et al specifically point out that "PTFE coated cookware does not appear to be a significant source of PFOA."

Begley et al, 2005. Perfluorochemicals: Potential sources of and migration from food packaging. Food Additives and Contaminants 22, pp. 1023-1031.

[Patrick S]

Regarding the migration of PFOA from PTFE-coated cookware under more realistic conditions (i.e., conditions similar to cooking, that don't involve grinding the coating to powder and using powerful solvents), here's the abstract from a recent paper:

Salts of pentadecafluorooctanoic acid (PFOA) are polymerization aids used in the manufacture of fluoropolymers; one of the applications of fluoropolymers is the coating of metal cookware products. A method was developed to determine if PFOA might be present in and extracted from the surface of commercial frying pans coated with a DuPont fluoropolymer under simulated cooking conditions. Commercial grade cookware was obtained, then extracted with water and ethanol/water mixtures at 100 and 125 degrees C, and the resulting extracts were analyzed by liquid chromatography tandem mass spectrometry (LC/MS/MS). Detection and quantification limits as low as 100 pg cm(-2) were demonstrated. None of the fluoropolymer treated cookware samples analyzed showed detectable levels of PFOA when extracted under simulated cooking conditions.

Powley et al, 2005. Determination of perfluorooctanoic acid (PFOA) extractable from the surface of commercial cookware under simulated cooking conditions by LC/MS/MS. The Analyst 130, 1299-302.

[Patrick S]

Admin: threads merged.

The EPA has reviewed testing results and found that a chemical used in Teflon non-stick cookware has a strong link to both cancer and birth defects. Called PFOA, the chemical is a key element in giving Teflon it's non-stick qualities.

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I missed this yesterday.

The first sentence in the above is, at best, highly misleading. The following is cut-and-pasted from what I wrote on another thread, summarizing the EPA's very own draft risk assessment of PFOA:

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I just got done reading the EPA's draft PFOA risk assessment, and it includes some very interesting information. Regarding studies that have examined the effects of PFOA exposure in humans (as opposed to high-dose rodent experiments), the draft assessment states:

"Two mortality studies, a morbidity study, and studies examining effects on the liver, pancreas, endocrine system, and lipid metabolism, have been conducted to date.  Studies have not shown any effects directly associated with PFOA exposure."

It is true that PFOA, like approximately half of all chemicals tested in high-dose feeding studies, is a rodent carcinogen. In particular, high-dose rodent experiments show an increase in liver and pancreatic tumors. However, the draft assessment points out that the mode-of-action [MOA] for these tumors is such that humans are much less susceptible to such effects.

"The overall weight of evidence suggests that the rodent MOA for liver tumors is unlikely to occur in humans, taking kinetics and dynamic factors into account."

For instance, the draft assessment points out that PFOA causes liver tumors in rodents by acting on what are called peroxisome proliferator-activated receptors (PPARs). These are receptors on hepatocytes (liver cells) which, when over-activated, cause the proliferation of certain cellular organelles called peroxisomes. The details are not really important, but what is important is that compounds that cause rodent tumors by a PPAR mode of action do not cause tumors in other species, such as guinea pigs, dogs and primates. One of the reasons may be that human hepatocytes have only 5-10% the PPARs that rodents have. Confirming this, the draft assessment reports that there was

"[n]o evidence of peroxisome proliferation in 6-month Cynomolgus monkey study."

It is also interesting to note that, according to this article, the rats that developed the liver tumors were being dosed with PFOA at a concentration 25,000 times higher than what is currently being found in human blood (125ppm versus 5ppb). In sum, not only is it doubtful that PFOA can cause human liver cancers at all, it is clear that humans are ingesting doses many thousand times lower than that which causes liver tumors in the most-susceptible species.

The mode of action for rodent pancreatic cancers also casts doubt on the relevance of PFOA to humans. It is thought that the pancrease tumors in the rats is caused by an increase in cholecystokinin (CCK). As with the PPARs, CCK receptors are much lower in humans than rodents, and the "cynomolgus monkey study with PFOA did not demonstrate any compound-related effects on CCK levels."

SNIP

4. PFOA is a rodent carcinogen, but the mechanism by which it causes rodent cancers is species-specific and probably not relevant to humans, according to the EPA draft risk assessment.

5. PFOA has not been shown to cause cancer in any non-rodent species.

6. PFOA has only been shown to cause cancer in rodents at doses that are many thousands of times higher than that found in human blood.

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[Patrick S]

There HAVE been human deaths attributed to teflon poisoning (ie: leaving a pan on the stove and falling asleep; perhaps in a drunken stupor, but whatever...the guy died) I'm a critical care nurse and I've SEEN people with teflon poisoning on ventilators. It's not just an "urban myth".

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Ok, I realize this statement was made over two years ago, but NVNVGirl, if you are still around, would you mind substantiating the claims you make above? I have been unable to find a single documented case of death or respiratory failure resulting from inhalation of emissions from overheated Teflon cookware. So, I find remarkable your claim to have seen "people", plural, on ventilators, plural, as a result "teflon posoning."

Edited January 31, 2006 by Patrick S (log)

[Jim Dixon]

When I was a kid it was taken as gospel (by the other kids, anyway) that you could kill a person by getting some 'teflon paint' (I've never seen any), applying it to waxed paper, peeling some off after it dried, and inserting a sliver into a cigarette (everybody smoked back then). When the target lit up, they'd inhale the teflon and die.

Jim

[inventolux]

Geez next were gonna find out that what we put in the pan shortens our lifespans? Then were really screwed. Im sorry but I just cant live without my late night infomercial set of non stick pans - these guys got it all wrong.

[ned]

Admin: threads merged.

I've often been accused of being a little slow on the uptake. I only heard rumblings about the risks of teflon in the last few months although I've been wary of worn teflon pans for some time. Now I hear something about how if a teflon pan is left on high heat for an indeterminate amount of time--a long time is what I've read--it can be dangerous. That happens in my kitchen pretty often if I'm making an omelette and turn my back on it do something else or if I sear some fish or any other protien that benefits from cooking in non-stick. We can be certain that teflon pans get overheated in restaurant kitchens all the time. This is not to mention all of the unsuspecting or uncaring teflon users at home and in commercial kitchens who use metal forks or spatulas and scrape up the coating and mix it in with food.

Is the risk currently considered so small that the government isn't recalling all teflon? Is this about lobbyists? Am I an alarmist? I haven't thrown my teflon pans away yet. They're too damn useful. I'm curious to hear what others have come up with on this topic. If there's a previous thread on the subject (that I didn't find) please merge this post in.

Here's a Washington Post article:

http://www.washingtonpost.com/wp-dyn/conte...5062801458.html

[west2100]

I most definitely misread the article. Paranoid character aside, I have been a bit leery of teflon pans as of late, due to increasing news stories about them and whatnot.

On the good side, it brought me to finally invest in a couple of stainless steel frypans. At least my conscience will feel healthier, even if body is no better for it.

[Alex]

Some statistical and scientific common sense from George Mason University

[halloweencat]

Admin: Threads merged.

http://seattletimes.nwsource.com/html/nati...2_teflon16.html

Chemical in Teflon a likely carcinogen

By Randall Chase

The Associated Press

DOVER, Del. — A group of scientific advisers to the Environmental Protection Agency voted unanimously Wednesday to approve a recommendation that a chemical used in the manufacture of Teflon and other nonstick and stain-resistant products should be considered a likely carcinogen.

The approval of the EPA's Science Advisory Board is conditioned on minor clarifications being made to a draft report submitted by a review panel, but no major changes will be made to the panel's findings on perfluorooctanoic acid, also known as C-8.

[Patrick S]

This subject has been done to death on this thread and this thread. Bullet points:

This chemical is apparently only a carcinogen in rodents, and causes cancer via mechanisms that appear to be species-specific and not applicable to other mammals.

The doses that cause cancer in rodents are many thousands of times higher than the dose humans are exposed to.

Several studies have been done to see if a measurable quantity of PFOA migrates from Teflon to food during cooking, and all have been negative.

[JohnL]

I think the key here is: the government is on the case. The scientists are investigating things.

The industry is on notice and looking at things as well.

All in all, seems there is cause for some awareness and maybe some concern but no cause for alarm or panic.

(I still like the way my teflon pan works and will continue to use it)

[halloweencat]

it was a news item, thus i thought it had merit.

cheers --

[eje]

Last month, the EPA asked the eight U.S. companies that use PFOA to virtually eliminate public exposure to the chemical. The companies were expected to comply with the voluntary measure, cutting releases from their plants and products by 95 percent over the next four years and completely soon after that.

I have no evidence to back this up; but, to me this just means these companies will move manufacture of items using PFOA overseas, where they can pollute with near impunity.

Unless I'm mistaken, most teflon coated cookware is already made in Asia, a lot of it by this man, Stanley Cheng.