What is PTFE?
Updated: Aug 8, 2022
Teflon and all other non-stick cookware have had some really bad press in the past few years and it's difficult to understand what you should do with your existing non-stick pan and what to look out for when replacing it. With so many new non-stick products being sold as "toxic-free", "healthy" and "PFOA-free" how do you gain trust in these new products when we've all been using what is now regarded as "toxic" cookware for over 50 years?
Why do we need non-stick cookware?
When we cook protein- and carbohydrate-rich food, the bonds break down and want to create new bonds, and lucky enough for us, they really like to bond with metallic surfaces. To reduce the chance of these bonds occurring, we can add oil. When you add food to a hot pan with hot oil, the food will release and vaporise water while cooking. This process literally levitates the food on top of the oil. WHAT!? Crazy right? Now, this only reduces the chance of the proteins and carbs bonding with the pan and if you don't maintain the correct cooking temperature, you'll end up with a big sticky mess. I’m sure you’ve at least once had the joy of trying to scrub eggs off your pan after they've fused with the surface. So to make the cooking of protein- and carbohydrate-rich foods easier, engineers developed Teflon (PTFE), a material that proteins and carbohydrates don't want to bond to.
What is it?
Polytetrafluoroethylene (chemists are great with names) shortens to PTFE, otherwise known as Teflon. This is a plastic material and a VERY slippery plastic at that. It is on the podium in 3rd place as the slipperiest (lowest coefficient of friction) of any known solid on earth! Combining this with the hydrophobic (water repellent) property of PTFE results in it being the perfect material to cook on without any food bonding to the surface. The joys of Teflon and other non-stick coatings are that food is easier to prepare and cleaning is a piece of cake.
Where is it used?
PTFE (Teflon) is used on all sorts of cooking equipment and also used extensively in outdoor equipment such as tents and jackets for its ability to repel water. Gore-Tex is a well-known example of this which is fundamentally a piece of PTFE that has been stretched so far that it allows water vapour through but repels water droplets, pretty cool huh?
Why is it bad?
Per- and polyfluoroalkyl (PFAS) substances are a group of man-made chemicals that include PFOA, PFBS, GenXTM and over 4000 others. A chemical from this group is required as a processing aid in the production of PTFE (PFOA was used for over 50 years) and this is where the joy of PTFE ends. All chemicals in the PFAS group are bio-accumulating (which means an organism is accumulating a substance faster than it can remove it) and as a result, these 'forever chemicals' have contaminated the majority of us humans, wildlife and ecosystems. It really is everywhere, which is not great when the list of potential health effects are as follows:
Low birth weight
Liver tissue damage
Disrupts immune system
So if PFAS chemicals are so bad why do we still use them?
The demand for non-stick cookware is massive and in trying to fulfil this demand the manufacturing and science of trying to create safe PTFE is moving faster than consequential health studies can be conducted. Only a few chemicals from the PFAS group have been studied for their long-term health implications. You might have heard companies marketing their cookware as "PFOA-free". The use of PFOA in the production of Teflon is what caused the massive lawsuit against Du Pont in America (The Devil We Know is a multi-award-winning documentary about this and, although dramatised, it's pretty scary. Since then, engineers have been trialling many other chemicals from the PFAS group in the hope to find a safe alternative to PFOA. Every new chemical that has been studied (For example, GenXTM and PFBS) have shown to cause similar health effects and environmental damage to PFOA and has subsequently been banned. There might be a safe alternative out there, but when the European Chemicals Agency (ECHA) is fighting for a “Restriction of per- and polyfluoroalkyl substances (PFAS) under REACH”, the future for PFAS is not looking too bright.
Is it safe to cook in a Teflon (non-stick) pan?
YES! PTFE - which is the surface you are cooking on - is very stable and inert when used below 260°C (500°F). You could, in theory, eat chunks off your pan if you wish and it shouldn't do you any harm (please don't try this at home). PTFE begins to break down at temperatures above 260°C (500°F) and the fumes this gives off are fatal to birds and cause some nasty flu-like symptoms in humans. If you're reading this and getting freaked out about the non-stick pan you have in your kitchen, don't ditch it! Just make sure you're careful with how you cook with it. As the majority of the environmental damage is done in creating the pan, you might as well use it while the non-stick surface is intact. Things which require low heat (e.g. scrambled eggs) are perfect for cooking in your non-stick pan, but if you're into high-temperature cooking (e.g. searing) then you are best looking for an alternative.
Longevity and recyclability of PTFE
As we all know, you can't use metal utensils in a non-stick pan as you will scratch the surface and before you know it, that super slick surface isn't the slippery dream it once was. It's inevitable that your coating will degrade with use and even if you're super careful you're looking at about 3-5 years tops. Although most non-stick pans are considered "recyclable", recycling is not straightforward. For easy (low energy and economically viable) recycling, an item has to be a mono-material, or made up of multiple materials that can easily be disassembled into singular recyclable materials. To recycle a typical non-stick pan, the parts have to be separated, then the PTFE coating has to be removed, with the latter not being an easy task and the reason why most recycling centres do not actually accept non-stick cookware for recycling.
We believe a PTFE non-stick pan shouldn't go near open flame
Campfires, BBQ's and all open flames can get screaming hot. We've seen and heard of people melting aluminium cookware on a campfire! Aluminium melts at around 660°C (1220°F) which is way higher than the temperature required to break down the PTFE coating. Even if you've got mad heat management skills with open flame, we believe the risk is too great. If you need your cookware to sustain a life in flames, you can read our article on materials safe for open-flame cooking.
What are the alternatives?
There are heaps of new PTFE-free non-stick coatings that all claim to be safe and non-hazardous. Thermalon is a popular new one and used by Greenpan. Thermalon might be the safe answer to the demand for a new Teflon (non-stick), but it's too new for any health or environmental study to be conclusive. In our view, the only tried and tested cookware materials that cause minimal impact to the environment and our health are uncoated cookware materials. We've been using uncoated cookware since the Iron Age and look where we've got to since then! Furthermore, uncoated cast iron and carbon steel can be seasoned to create your own DIY non-stick layer without all the nasties. Cast iron, carbon steel and stainless steel are what we believe in as they are safe to cook in, cause minimal environmental impact and can last for centuries.
If you want to cause minimal environmental impact opt for uncoated cookware
Non-stick (PTFE) cookware is safe to cook on if used below 260°C (500°F)
We strongly advise against the use of all non-stick cookware over open flame
You don't need a non-stick pan if you learn how to prevent food sticking in the first place
If you are looking for new cookware then check out our article on selecting the right cookware material.