What is Teflon? Anybody who’s spent time at the stove knows that Teflon pans were the coolest culinary invention of the time. Teflon is the trademark name for polytetrafluoroethylene (PTFE), used to create non-stick surfaces. It’s really good at what it does. Like most things in life, it has its fans and its detractors. Whichever side hollers louder gets the greater attention at a particular time, but there is science that can’t be ignored, and common sense that, apparently more often than not, is. For a product that was accidentally discovered while looking for a new refrigerant, Teflon has done pretty well since the late 1940’s. The first frying pan debuted in 1961.
Considerable controversy surrounds the base chemical from which Teflon is made—perfluorooctanoic acid (PFOA). The problem is that offgasing of fluoride derivatives is toxic to the respiratory system, as evidenced by necropsy of dead chicks that were exposed to Teflon-coated heat lamp bulbs in their hatching pens. Accounting for all possible confounders and variables, it was discovered that PFOA could be the only cause of pulmonary lesions and edema in those animals (Boucher, 2000). For the chicks to have expired from Teflon offgasing, the temperature of the heat lamps would have had to have been above 325°F and the base material of low molecular weight (Seidel, 1991). Birds have been used as indicator species in coal mines for years, where the presence of toxic gases, notably carbon monoxide and methane, or the shortage of air would cause their asphyxiation long before it affected humans. Birds are a captive audience, whether in a coop or a cage. Even if their physiology reacted adversely to an airborne toxin, they could not have vacated the space. A human could, unless lacking common sense. Even so, humans are not living under heat lamps, much less lamps with Teflon coating.
Why Teflon Has a Bad "Rap" Some research says Teflon coated frying pans do not present serious concerns until heated to a temperature at which Teflon can break down to emit PFOA—about 600°F. Normal sauté temperatures hover around 320°F. Hmm, let’s see…the caramelization phenomenon called Maillard happens around 250°F (although it can happen at lower temperatures because Maillard is a reaction between amino acids and sugars, not just a response to heat). The most common cooking oils smoke far below 600°F, and that would force you out of the kitchen. One more thing…the pan should be empty to present a hazard. Considering the amount of PTFE resin on the pan, the usual frying temperatures, and the size and ventilation of a home or commercial kitchen, it’s unlikely that even abuse temperatures would cause polymer fume fever. Experiments conducted in the mid 1970’s found birds to be more sensitive to Teflon offgases than rats, but both to be more sensitive to naturally occurring frying media than to PTFE fumes. In fact, cooking oils kept at temperatures that offgas Teflon would cause flashing that would kill a bird and later cause a fire (Waritz, 1975). If you believe that the danger is in the dose, you’d probably have lots of company. But the prediction that all Teflon pans will be pulled from the stores by 2015 makes you wonder if somebody knows something the rest of us don’t.
Are there alternatives? Cast Iron: Almost nothing is slicker than Teflon. However, there’s a low-tech solution that’s been around for centuries…cast iron. It’s cheaper than a coated pan, it browns food better, and is almost as non-stick, once properly seasoned and cared for. In the presence of slightly acidic ingredients it adds iron to the food. That’s a good thing. Enameled cast iron may not contribute to daily mineral intake, but it does make cleanup easy and more thorough. On the other hand, it fares poorly at sticking resistance and tolerating searing heat. Chipping of the enamel and cost are issues to consider.
Aluminum: Some brands of pots and pans are now made from anodized aluminum. The process involves the formation of a hard oxide layer of the base metal on the surface of the cookware. Its name comes from the manner of electrolysis in which the aluminum becomes the anode of an electrical circuit. Such a process makes the surface harder than the base, making it non-stick, scratch-resistant and easy to clean. Because the metal is sealed, aluminum cannot leach into food. If you’re worried that aluminum could taint your food and contribute to cognitive decline, boil the pot or pan prior to cooking in order to increase the protective oxide layer (Karbouj, 2009).
Stainless Steel: Stainless steel is an option for replacing coated pans. This material contains a little more than ten percent chromium, and may also contain other metals, such as nickel and molybdenum, all of which may trickle into foods in barely detectable amounts. Because it resists corrosion and staining, stainless steel is a favorite, but few cooks realize there are different grades. Heat conductivity is not a strong point in stainless cookware, so cladding or layering with aluminum or copper is often done to improve energy absorption and distribution. Otherwise, the part of the pan directly over the heat gets super hot, while the circumference remains cooler.
Copper: Copper cookware is favored by professionals for sauces and sautés because it excels at heat-ups and even energy distribution. Copper can leach into foods in large amounts when heated, so the pans are usually lined with tin or stainless steel. If the lining is damaged, copper toxicity may ensue and present with a host of symptoms, including tarry stools, hypotension, and GI distress, followed by liver and kidney damage over the long term. It’s expensive and pretty to look at, but copper needs special care.
The bottom line in choosing cookware concerns not only the thermal properties of diffusion and heat capacity, but also the safety and gustatory properties, the latter defining the influence of the material on the taste of the food. Aluminum and copper react with foods. Stainless steel doesn’t, but has poor thermal diffusivity. To overcome these vices, manufacturers have found ways to relieve us of heavy wallets. Combine the non-reactivity of stainless with the thermal properties of aluminum or copper.
We didn’t mention thickness of pan material. Since heat capacity is a function of mass, density is a factor. Cast iron is usually thicker than other pans. Nothing beats cast iron for consistent heat. Seasoning makes it relatively non-stick and, if done correctly, almost non-reactive except for the most acidic ingredients. A fault is its weight. If you prefer a clad stainless, the thicker, the better, but that equals more money, and if you have nickel sensitivity, forget it. Titanium might be the latest rage, but we’ll have to see how that pans out. Smile.
Barrow CS, Lucia H, Stock MF, Alarie Y. Development of methodologies to assess the relative hazards from thermal decomposition products of polymeric materials. Am Ind Hyg Assoc J. 1979 May;40(5):408-23.
Boucher M, Ehmler TJ, Bermudez AJ. Polytetrafluoroethylene gas intoxication in broiler chickens. Avian Dis. 2000 Apr-Jun;44(2):449-53.
Bradley EL, Read WA, Castle L. Investigation into the migration potential of coating materials from cookware products. Food Addit Contam. 2007 Mar;24(3):326-35.
S.J. Genuis, D. Birkholz, M. Ralitsch, N. Thibault Human detoxification of perfluorinated compounds Public Health. Volume 124, Issue 7 , Pages 367-375, July 2010
Johnston CJ, Finkelstein JN, Gelein R, Baggs R, Oberdörster G. Characterization of the early pulmonary inflammatory response associated with PTFE fume exposure. Toxicol Appl Pharmacol. 1996 Sep;140(1):154-63.
Johnston CJ, Finkelstein JN, Mercer P, Corson N, Gelein R, Oberdörster G. Pulmonary effects induced by ultrafine PTFE particles. Toxicol Appl Pharmacol. 2000 Nov 1;168(3):208-15.
Karbouj R, Desloges I, Nortier P. A simple pre-treatment of aluminium cookware to minimize aluminium transfer to food. Food Chem Toxicol. 2009 Mar;47(3):571-7. Epub 2008 Dec 27.
Kontou N, Psaltopoulou T, Soupos N, Polychronopoulos E, Linos A, Xinopoulos D, Panagiotakos DB.
The role of number of meals, coffee intake, salt and type of cookware on colorectal cancer development in the context of the Mediterranean diet.
Public Health Nutr. 2012 Aug 8:1-8.
Kuligowski J, Halperin KM. Stainless steel cookware as a significant source of nickel, chromium, and iron. Arch Environ Contam Toxicol. 1992 Aug;23(2):211-5.
Kumar R, Srivastava PK, Srivastava SP. Leaching of heavy metals (Cr, Fe, and Ni) from stainless steel utensils in food simulants and food materials. Bull Environ Contam Toxicol. 1994 Aug;53(2):259-66.
Oberdörster G. Pulmonary effects of inhaled ultrafine particles. Int Arch Occup Environ Health. 2001 Jan;74(1):1-8.
Quintaes KD, Amaya-Farfan J, Morgano MA, Mantovani DM. Soapstone (steatite) cookware as a source of minerals. Food Addit Contam. 2002 Feb;19(2):134-43.
Seidel WC, Scherer KV Jr, Cline D Jr, Olson AH, Bonesteel JK, Church DF, Nuggehalli S, Pryor WA. Chemical, physical, and toxicological characterization of fumes produced by heating tetrafluoroethene homopolymer and its copolymers with hexafluoropropene and perfluoro(propyl vinyl ether). Chem Res Toxicol. 1991 Mar-Apr;4(2):229-36.
Shuster KA, Brock KL, Dysko RC, DiRita VJ, Bergin IL. Polytetrafluoroethylene toxicosis in recently hatched chickens (Gallus domesticus). Comp Med. 2012 Feb;62(1):49-52.
Waritz RS. An industrial approach to evaluation of pyrolysis and combustion hazards. Environ Health Perspect. 1975 Jun;11:197-202.
Wells RE, Slocombe RF, Trapp AL. Acute toxicosis of budgerigars (Melopsittacus undulatus) caused by pyrolysis products from heated polytetrafluoroethylene: clinical study. Am J Vet Res. 1982 Jul;43(7):1238-42.
*These statements have not been evaluated by the FDA. These products are not intended to treat, diagnose, cure, or prevent any disease.
August 01, 2012