Teflon - Is It Safe?

From The Frying Pan Into the Fire

The controversy about "is Teflon safe?" blazes on, with people asking me if they should ditch their Teflon cookware and purchase a set of something else. (One well-known holistic doctor --- who happens to be selling ceramic-lined cast iron cookware --- is particularly vocal about the grave dangers of Teflon pots and pans).

Like all controversies, there are two sides to this story. Here's my medical insider's "take" on Teflon.

What the Heck is Teflon Anyway?

Teflon, a slick, non-stick substance used in cookware and a wide variety of other products, was patented by the DuPont Company in the 1930's. It's non-stick nature makes for low or no-fat cooking and easy clean-up in pots and pans. "Teflon" is a brand name, but there are many other manufacturers of the same non-stick product.

The controversy about Teflon is whether or not the substance is safe.

The problem isn't with Teflon itself, but with one of the chemicals used in it's manufacture. Perfluorooctanoic acid, or PFOA, is used in the manufacture of compounds called fluoropolymers which are in turn used to make Teflon and other products such as oil and water-repellent coatings on carpet, textiles, leather and paper and "breathable" materials such as Gore-Tex.

The PFOA, found to be elevated in the bloodstream of the general American population (1) has been shown to cause cancer, liver damage, growth defects, immune-system damage and death in lab animals. Although it's effect hasn't been well-studied in humans, lab animal evidence gives ample cause for concern.(2,3)

But here's where PFOA and Teflon part ways. The PFOA is used in the manufacture of Teflon. When this chemical is disposed of near factories, or off-gases during the manufacturing process, it is dangerous. DuPont has already settled several lawsuits for contaminating water supplies with PFOA.(4) There is substantiative evidence that PFOA may pose health risks. However, PFOA is an "intermediate" chemical that is not present in the final Teflon product.

So what's the problem? DuPont and other non-stick manufacturers don't know how to make Teflon without PFOA, and PFOA is a "likely carcinogen." But as for your Teflon pots and pans, the PFOA is driven out during the manufacturing process. There is no appreciable PFOA remaining in the finished Teflon product.

Other Health Concerns with Teflon

PFOA isn't the real problem with Teflon cookware in your kitchen.
The other consideration is that non-stick fry pans can release toxins at high temperatures. Teflon is known to give off a mix of toxic particles and gases at high temperatures. These chemicals are known to be poisonous to birds in small doses and in humans they can cause headaches, chills, backache, and fever - a condition known as "Teflon flu". (5-7)

So if Teflon gives off a dangerous cocktail of chemicals when heated, we should get rid of our Teflon cookware, right? Not so fast.

These toxic chemicals are only given off at high temperatures. How high? The Environmental Working Group (EWG), a "watchdog" organization that often puts out spurious science in the name of "consumer protection," says that Teflon begins to deteriorate at 500 degrees Fahrenheit and will "significantly decompose" at 660 degrees Fahrenheit. At temperatures of 660 and above, Teflon off-gases it's toxic chemicals. Fast summary on this paragraph: Teflon cookware can become dangerous at temperatures above 660 degrees.

At temperatures between 225-525 F, most normal cooking oils are at their "smoke point" and close to their "flash point" (the point at which they will ignite). Flash point poses a serious risk of grease fire, but even at the lower "smoke point," fats and oils are "denatured," thus emitting smoke and vapors that are hazardous to human and pet health, regardless of the type of pan used.(8) Oils heated to their smoke points contain carcinogenic free- radicals. The smoke points of various cooking oils can be found on this nifty website, Cooking for Engineers. [ http://www.cookingforengineers.com/article/50/Smoke-Points-of-Various-Fats ]

My Personal "Temperature Test"

How hot is 660 degrees? Darned hot! Lead melts at 621 degrees Fahrenheit. According to some of the anti-Teflon sites," These temperatures can be reached if a pan is left sitting on a normal kitchen stove burner set on 'high' for as little as five minutes."

Excuse me? "As little as five minutes"? Who puts a dry pan on the stove on high for "as little as" five minutes? Cooks like this should be banned from the kitchen.

Being the ever-curious scientist that I am, I decided to test the temperatures that my teflon coated pans reach during normal cooking.
I used a laser thermometer, which registers accurately up to 482 F, to perform the tests.

I like to have my pan HOT when cooking a one-egg omelet. (It's the secret to getting a single egg to make such a big, beautiful meal).
I start with just a minute coating of coconut oil on the pan, probably less than 1/8 tsp. If the first drop of egg doesn't sizzle, the pan isn't hot enough.

Here are my test results:

My pan was "egg sizzling hot" at 256 degrees. After adding the egg, the temperature dropped to 135 degrees, the approximate cooking temperature for the rest of the omelet.

Next, I put the pan back on the stove (nearly dry by this time) for two minutes. The dry pan got up to 423 degrees. I added 1 tsp. of coconut oil and the temperature immediately dropped to 304 degrees. Adding some vegetables to sauté dropped the temperature down to 234 degrees and lower.

I have measured the pan temperature in a variety of my everyday cooking scenarios, including bacon. The 423 degrees mentioned above is the hottest I've ever seen the pan get, and this was a "test" condition. I really don't leave a dry pan on the stove EVER.

As much as I love all of you and as dedicated as I am to research, I wasn't about to leave a pan on "high" for five minutes to verify that it reached 660 degrees. But then, I would never leave a pan on the stove at that temperature unless I had had a heart attack, in which case my hot pan probably wouldn't be my biggest problem.

If It's Dangerous at High Temperatures, Why Not Get Rid of It?

Teflon has advantages. I can cook meals with very little fat, or even no fat at all if I use a bit of broth in the pan. This saves both calories and clean-up time. Old fashioned cast iron cookware requires quite a bit more oil and clean-up. Even enameled cookware requires more oil and clean-up.

Keep in mind that MANY things become dangerous at high temperatures. Your house is probably safe right now, but I guarantee if it were on fire, home-sweet-home would become toxic brew of chemical off-gassing. There are just some substances (many, in fact, in today's synthetic world) that are safe at low temperatures and dangerous at high temperatures. Teflon is no exception.

There is also concern about Teflon chips breaking loose and entering food once the surface has been scratched or damaged. (A good reason to always use plastic or wooden utensils with your Teflon pans).

As far as anyone knows, Teflon in this form will pass through the body unchanged. It is inert. That is why Teflon and similar non-stick surfaces are used in artificial arteries, hip joint replacement parts, and other surgical implants. The material is extremely durable, and so inert that it does not appear to migrate.(11,12.)

Is the "Alternative" Really Safer?

One holistic physician with a major online presence is selling enameled cast iron as an alternative to Teflon. A big part of his argument is the toxic PFOA, although as discussed above, this is a known carcinogen in the manufacture of Teflon, not in the final product.

Yes, there are substances which may off-gas at high temperatures. If you routinely put a a totally empty pan on the stove and leave it on high heat for a few minutes (not recommended), this can certainly be a concern. Hint: NEVER have an unattended pan on the stove and always have oil, water or something in the pan as it heats. Problem solved.

Finally, I am not fully convinced that enameled cookware from China is a good trade off for my Teflon. Here's why:

"Enamel," the supposedly safe coating in the popularized alternative to Teflon, is made with a variety of metals. Lead and cadmium have been found in enameled cookware, including both domestic and imported enamel ware. (9,10).The use of these toxic metals in enameled cookware has been "banned" by the FDA, but actual verification is often lacking. And leaching of toxic metals from contaminated enameled cookware does not decrease over time or with repeated use. (10)

The latest "healthy offering" for enameled cookware comes from China. Yes, China, the land that has brought us contaminated toothpaste, baby toys and even drugs. And now I'm supposed to be confident that trading in my Teflon (which I do not overheat) for enameled cookware of dubious origin is a good trade-off? Color me skeptical.

Dr. Myatt's Bottom Line on Teflon (as of May 2008)

I'm not defending Teflon. The PFOA's that manufacturers have released into the environment are "probable carcinogens," and that's reason enough to halt their release into the environment until more is known about their safety.  But the Teflon in your kitchen, if used judiciously (without high heat on a dry pan) is probably one of your lesser environmental exposure risks. Most alternatives, with the exception of plain ol' cast-iron, raises just as many questions as Teflon.

My research (both in the scientific literature AND in my own kitchen), have not convinced me to throw out my Teflon pots and pans.
I believe Teflon coated pans are safe at regular cooking temperatures and safe even if small pieces of the coating flake off, since this stuff seems to be quite inert. (Remember, this coating is used extensively in medical devices because it is so inert).

I question the safety of enamel-coated cast iron, especially that imported from China, since the enamel is made with metals and has been found to be cadmium and lead contaminated in the past. So who's checking the present-day imports?

If you want to be super-safe, cook with cast iron. Of course, it's heavy, tends to stick if not well-seasoned and well-oiled, but there are no known contaminants in the cookware. AND, you can put a dry pan on the stove and walk away (not recommended). You might burn the house down, but you won't have to worry about toxic off-gassing from your cookware!

That's the View from My Kitchen Today,
Dr. Myatt

P.S. Of course, I reserve the right to change my mind on this opinion if new information becomes available to me. But as of May 2008, I'm hanging on to my Teflon pots and pans.

References

1.) Antonia M. Calafata, et al. Perfluorinated chemicals in selected residents of the American continent. Chemosphere Volume 63, Issue 3, April 2006, Pages 490-496.

2.) Rosen MB, Abbott BD, et al. Gene Profiling in the Livers of Wild-Type and PPAR{alpha}-Null Mice Exposed to Perfluorooctanoic Acid (PFOA). Toxicol Pathol. 2008 May 8 [Epub ahead of print].

3.) Fei C, McLaughlin JK, Tarone RE, Olsen J. Fetal Growth Indicators and Perfluorinated Chemicals: A Study in the Danish National Birth Cohort. Am J Epidemiol. 2008 May 5 [Epub ahead of print].

4.) http://injury.findlaw.com/teflon/teflon-news.html

5.) William Byrne Cogar et al. CBRNE - Lung-Damaging Agents, Toxic Smokes: NOx, HC, RP, FS, FM, SGF2, Teflon. eMedicine Specialties > Emergency Medicine > WARFARE - CHEMICAL, BIOLOGICAL, RADIOLOGICAL, NUCLEAR AND EXPLOSIVES.

6.) Patel MM, Miller MA, Chomchai S. Polymer fume fever after use of a household product. Am J Emerg Med. Nov 2006;24(7):880-1.

7.) Shusterman DJ.Polymer fume fever and other fluorocarbon pyrolysis-related syndromes.Occup Med. 1993 Jul-Sep;8(3):519-31.

8.) AMERICAN COUNCIL ON SCIENCE AND HEALTH. The Top Ten Unfounded Health Scares of 2006 #6 Teflon Contains a Cancer-Causing Chemical (PFOA)

9.) Baczynskyj WM, Yess NJ.U.S. Food and Drug Administration monitoring of lead in domestic and imported ceramic dinnerware. J AOAC Int. 1995 May-Jun;78(3):610-4.

10.) Sheets RW. Extraction of lead, cadmium and zinc from overglaze decorations on ceramic dinnerware by acidic and basic food substances.Sci Total Environ. 1997 Apr 30;197(1-3):167-75.

11.) Brandão CM, Guedes MA, da Silva MF, Vieira ML, Pomerantzeff PM, Stolf NA. Mitral valve repair with "Double Teflon" technique: 10-year results.Rev Bras Cir Cardiovasc. 2007 Dec;22(4):448-53.

12.) Queen TA, Palmer FR 3rd.Gore-Tex for nasal augmentation: a recent series and a review of the literature. Ann Otol Rhinol Laryngol. 1995 Nov;104(11):850-2.