I once got into an argument with a coworker about the non-reactivity and biocompatibility of PTFE (Teflon). What a fool: I had worked with the stuff on medical devices at a previous startup.
In any case out of annoyance I swallowed some teflon plumbing tape. A few days later I had to take an international flight and, ta-da, excreted it in the aircraft toilet. That was lucky as I had a convenient metal shelf and not a bowl of water. As I had predicted it was intact and perfectly white.
I sent my colleague a photo from my phone. He was annoyed when I got home.
PS: I had been carrying around a cheap disposable pen for this purpose. I stole it from his desk.
> I sent my colleague a photo from my phone. He was annoyed when I got home.
Did you...clean it off? Or just take a picture of it in the bowl along with the rest of the contents? I'd like to think I could the former, but if one of my coworkers sent me a picture of their faeces, annoyed wouldn't even begin to describe how I'd feel. Being completely incorrect on a technical matter, even foolishly so, isn't anywhere close to warranting being treated that shitty (pun fully intended but unfortunately not enough to mitigate my disgust at the idea of being sent a picture like this from a collegeaue).
A few *days* later? I guess I don't know the expected intestinal transit time for teflon tape.
So it emerged white. Firstly, that seems odd. Secondly, how do you know no particulates were shed inside you? Surely just eyeballing it isn't going to tell you much?
I think it would be odd had it not emerged white. It was white thread tape (I've never seen any other color). And it's not like it should react with the contents of my bowel.
> Secondly, how do you know no particulates were shed inside you? Surely just eyeballing it isn't going to tell you much?
You're right, except that I already knew the answer: as I mentioned in my comment I'd already used PTFE in a previous job; I've dissected and otherwise processed innumerable tissue samples from animals injected with various biocompatible polymers in the process of preclinical studies. Teflon is quite common in implanted medical devices for the very reason that it is safe and doesn't tend to break down.
Some polymers are considered safe but clear from the body through mechanisms nobody has worked out. For example the polymer fillers some people have injected to push out wrinkles are, as far as I remember, a safe mw of PEG that just seems to...go away.
I've used PEG as a drug carrier but have used the drug to determine how it was breaking down (or microscopy), rather than trying to assay the carrier itself. FDA is super concerned about the API (i.e. drug) and most excipients, but for a neutral GRAS carrier like PEG. meh. Though they do care a lot that you make sure the mw is in one of the GRAS ranges!
So.. does that mean there isn't actually anything to worry about with teflon pans? I've certainly heard claims that you can end up with particles in your food, which is bad somehow. Seems unlikely there's evidence behind that given that the pans are still sold, but then, plenty of dangerous things are. Sounds like even if it does flake off in your food, no big deal? Or can cooking it make it into something more reactive?
If you overheat it (which might happen if you leave the pan on heat with no contents, or you’re trying to cook something like steak at high heat) then it breaks down into a fairly nasty gas which is fatal to birds and gives humans flu like symptoms (exact health effects of this aren’t known).
And as other people have mentioned, the manufacturing process involves some really nasty chemicals, which often end up leaking out into the environment.
Have a look at this Ted-ed video [0]. What they basically say is that Teflon is not dangerous in itself, what is dangerous is the product they use to glue it to the pan.
If manufacturer has convinced regulators that Teflon isn't dangerous just because the danger is in something that always has to be used with Teflon and not Teflon itself, surely that's criminal?
It’s not uncommon in chemistry for two very reactive elements/compounds to combine into a molecule that is very stable and relatively benign.
Sodium and Chlorine == table salt, for instance.
Another example - Aluminum is pretty safe to be around, especially if it’s anodized.
Anodized aluminum is even perfectly safe for use as a pan for cooking pretty much any food.
Non-anodized is decently safe, just don’t use it with acidic foods. It’s common in large commercial cookware, though stainless is steadily replacing it.
You really don’t want to be exposed to the chemicals used to refine aluminum or anodize aluminum though, as they include fluorine gas, chromic acid, etc.
Same with titanium, stainless steel (albeit stainless generally doesn’t need a secondary coating), etc.
I have some that's pale pearly gray. Not sure if they just cheaped out on a colorant or something, but it's definitely bargain-basement stuff so that wouldn't surprise me.
> I think it would be odd had it not emerged white. It was white thread tape
You seem to be implying that it also was white when it went in? This wasn't stated in the parent post. But in that case, emerging white, same as when it went in, is a good outcome.
Firstly, "it's always white" is domain-specific knowledge that most of us don't have. I've seen the white plumbing tape for sure, but I didn't make universal assumptions based on that.
> Firstly, "it's always white" is domain-specific knowledge that most of us don't have.
How is common home repair supplies count as "domain-specific"? You don't have some teflon tape in a storage drawer somewhere in your house? Have you never replaced a faucet aerator or shower head?
As to the other tape, that's apparently for gas connections (I've never of it personally) when the original poster specifically specified plumbing tape.
> You don't have some teflon tape in a storage drawer somewhere in your house?
Probably, I'd have to look. But like I said "the last one that I saw was white" is one thing, "it's always white" is another very different thing. Is this a standard that it _has to be white_? If you can't answer that, then you have no case at all that it's not "domain specific knowledge".
It seems likely to be true based on a lot of compelling evidence. What am I missing?
Even if the tape appeared unchanged during transit of the GI tract, fragments of it could have detached from where it was damaged from being cut or torn from the roll. These fragments appear to make their homes in our bodies.
What harms might result from the ingestion of tiny bits of Teflon is something I suspect will be much more closely looked at now that we're learning more about the effects of microplastics and PFAS on the body. While we wait for science to do its thing, the more immediate concern is Polymer Fume Fever (https://www.fireengineering.com/firefighting/engine-company-...). Breathing PFIB sure seems like something best avoided. You can always keep a bird around like they did in mines. If your canary dies in your kitchen maybe open a window.
Folks should absolutely go ahead and snack on teflon if they want to, but where it's possible I see very little harm in taking a precautionary approach with PFAS, including teflon, especially considering DuPont's track record on deliberately and aggressively hiding known harms from the public and the environmental and safety concerns surrounding its production.
Teflon is not a dangerous PFAS. That's why it's downvoted.
Also no, Teflon cannot stay in your body. It's not available for biouptake. The non-reactivity of Teflon is it's entire point.
This is why Teflon coated pans are safe. You can break off pieces of it and consume it and it will be guaranteed to pass through your body.
Also further, "PFAS" has been turned into a buzzword when in fact it groups a huge number of chemicals, some of which are quite dangerous (and largely already banned) and some of which are completely safe. If you just say "PFAS" it's clear you don't actually know what you're talking about.
"If you just say "PFAS" it's clear you don't actually know what you're talking about."
That's funny, because clearly you don't know what you're talking about, or how PTFE is made.
I never said the PTFE was the problem. PTFE was manufactured using PFOA. DuPont replaced PFOA with GenX. We know PFOA is linked to various health concerns. We don't have much info on GenX, but the EPA has issued cautionary guidelines on potential health impact.
Also it's ironic how the person who successfully proved how Teflon goes unprocessed by body's food processing has internal organs and blood full of PFAS that is pumped into the environment as a byproduct of Teflon manufacturing.
Overheating a Teflon pan is pretty difficult to do, and even then it's not like it suddenly exposes your body to dangerous chemicals if you continue to use the pan after it's been overheated once.
It's not that difficult to heat the pan to 280 degrees by accident, which is all that's required, no? At that point you feel sick and your pet birds start to drop dead.
Note I said "after". And you'd have to leave it at 280 degrees for quite some time to get the temporary effects. Some good ventilation and taking the pan off the fire will end the effects.
If I'm remembering the statistics correctly, despite the millions of Teflon pans in the US, there is less than 1 case of people getting Teflon flu from cookware per year. It's just not something that happens. Lightning strikes humans more often.
The probability of me leaving pan on high heat by accident: high, done this multiple times. The probability of me reporting any sickness as teflon flu: zero because I had no idea that Teflon could cause anything like this until yesterday when I looked this up.
And we don't know anything about long-term effects.
Anyway it's pointless because no matter how safe teflon is the side products of its manufacturing should already be enough of concern to render it illegal but somehow no one cares
Fluorine is toxic. I don't care if you bind it to carbon and think it'll probably never break bonds in the vicinity of humans. Get that shit away from me, and especially don't coat my cookware with it!
If you think fluorine is toxic in any compound, let me tell you about dihydrogen monoxide. It’s found in over 90% of human tumor cells, and of course serves as a solvent to bring ionized fluorine into the body.
You are not responding to the best possible interpretation of my comment. It is obvious that literally everything in sufficient quantity will kill you.
I would rather drink a quantity of hydrogen peroxide, than an equal quantity of fluorine. Also, hydrogen peroxide is a compound, fluorine is an element.
I would rather breathe pressurized oxygen, than pressurized fluorine.
The lethal dose for hydrogen peroxide is 40 times that of fluoride. Think about a glass of hydrogen peroxide. Now imagine 1/40 of that, a tiny bit at the bottom of the glass. That's an equivalent amount.
> Also, hydrogen peroxide is a compound, fluorine is an element
That's my point: compounds can be poisonous, but the toxicity of an element depends on the compound it's in. PTFE is a compound that's non-toxic. It just doesn't react with anything in the body.
Carbon and fluorine form a really strong bond. This is both why F2 reacts with so much, and why PTFE reacts with so little.
This poster got perfect scores in all chemistry exams in high school. Since you've vapidly ad hominem'd me on authority, now let's hear what makes you the chemistry expert.
It’s kinda hilariously obvious. Compounds have different properties than their elements. Fluoride ion are safe enough to use in toothpaste, and protect teeth in fact. CFCs replaced ammonia as a refrigerant, because it is much much safer and inert in the absence of high energy photons. We still use HCFCs, and the F in there is for fluorine-carbon bonds.
The health effects of Teflon decay (only by overheating, really) are not caused by fluorine. They are caused by the decay products, tetrafluoroethylene and difluorocarbene. This has nothing to do with the fluorine part: you get symptoms of poisoning 4-8 hours later from those vapors, not like the immediate chemical burns of fluorine gas.
Compounds are just plain different than their elements. Mercury is pretty bad for you, but you could swallow a pure sample of mercury sulfide and nothing would happen to you. You have a little knowledge of chemistry but haven’t internalized the theories.
Also: good test scores in high school means you’re a perfect candidate for Dunning-Kruger. Anyway your internal model of chemicals is as a collection of atoms which are kinda like Legos, instead of thinking of bonds and electrical fields.
Hydrogen doesn’t cause toxicity in our bodies but I’m fairly sure oxygen does quite readily.
Water does as well. Many people experience mild forms of water toxicity, and although it’s rare, it can be fatal too. Oxygen is pretty dangerous stuff, you really do need to moderate intake and allow buffers in your body from having too much of it.
I never said the PTFE was the problem. PTFE was manufactured using PFOA. DuPont replaced PFOA with GenX. We know PFOA is linked to various health concerns. We don't have much info on GenX, but the EPA has issued cautionary guidelines on potential health impact. Both of these substances are PFAS.
I have a question, is PFAS still persist in processed PTFE? From what I read, the concerns are mostly with the manufacturing rather than the safety of the resin itself.
Yes, it is still found after processing. That's the main reason they replaced PFOA with a different PFAS - GenX. They did this so they could continue to coat cookware after PFOA was being banned by the FDA.
I assume the majority of the most important science humans have done was to win an argument or impress a woman (or, more rarely but more notably, a man).
Mostly men, for tenure or boasting purposes. Until quite recently women were excluded from science, as they were excluded from so many other interesting things.
Both criminals and scientists put in the biggest amount of energy into their "career" before they hit 30. Trying to impress a mate makes sense as an explanation. The peaking physical condition and declining Testosterone production after 30 might be another reason.
Depending on how reductionist you want to get (and if you're anything like me, that's quite reductionist), most everything we do is at least tangentially associated with impressing a mate.
It seems like an interesting topic, but this is the academic equivalent of turning a 30 second youtube video into a 15 minute presentation with intro, requets for engagement, outro, journal of feelings and learning, etc.
The result is an average of 1.71 days for an adult patient.
A lithopedion…, or stone baby, is a rare phenomenon which occurs most commonly when a fetus dies during an abdominal pregnancy,[1] is too large to be reabsorbed by the body, and calcifies on the outside as part of a foreign body reaction. . .
I have a vivid memory of myself swallowing pennies when I was probably 4. I think I saw my dad pretend to do it for a magic trick or something. I did it in secret … For all I know it’s still there. :)
I did see a TV segment showing some kind of ascetic in NYC that fed a length of string through his body and could slowly tug it back and forth over a period of days. I can't remember why he thought this was a good idea.
>I'm now a now a professor of pediatric emergency medicine, I have a quite large research portfolio. For what it's worth, I'm probably one of the leading children's emergency medicine researchers in the UK. But the research that has probably had the most impact is this, out all the stuff that I've done. I'm not sure how I feel about that. But if I go to my deathbed, and this is my most important contribution to science, well maybe that's not such a bad thing.
So, you can work hard, graduate medical school, become a professor, get to the top of your competitive field full of smart people, and publish a "quite large" body of research in prestigious journals - but of all of that, swallowing a Lego head ends up your most important contribution to science.
>Henry: We get people to swallow pill cameras all the time in our gastro department, and they're bigger than that. The numbers that we'd learned, although I'd learned as part of my pediatric training around what you will and won't pass and where the danger zones are, is that if something's greater than 110 millimeters, then it won't get around your duodenum.
110 mm is large, it is roughly 4 inches!
I doubt that something 110 mm in any of the three dimensions (apart maybe something like a piece of string) can be actually swallowed.
It cannot be 11 mm (as the lego head is about that size, and doesn't look like being near the "limit").
but they are recorded as exceptional, I was initially thinking of something loosely spherical, in that case it is more probably something less than 20 mm or 4/5 of an inch in size/diameter that can be ingested, bar the exceptional cases.
But all these recorded items seem like having needed to be removed, I couldn't find anything about something (say) 100 mm long that managed to "pass through" naturally.
Early North American settlers used corn cobs. They were abundant, they were soft and they were easy to handle. Sailors used something called a 'tow rag'. A tow rag was a long piece of frayed rope that dangled in the water.
So is this a sort of "There Was an Old Lady Who Swallowed a Fly" [0] idea except you have a fish swallow the Lego head, then you eat the fish. Next up you have a Mahi-Mahi or a Tuna eat your fish that ate the Lego head, then you eat that bigger fish ...
Where does this end, eating a Polar Bear that ate the fish that ate the fish that ate the Lego head? So yeah, you end up with Polar Bear liver poisoning. Yep, definitely want to avoid those micro plastics.
"The tiny batteries can get stuck in and severely burn the esophagus within two hours, which can lead to major injury or death."
So yes small things can get stuck in a child's digestive track. Why are these doctors trying to prove the opposite by demonstrating that an adult can easily digest a (common) child size object?
It's explained the first couple of lines of the article. They wanted to see how long plastic objects would pass through the system. They couldn't ethically ask a child to do, so themselves was the next best thing.
The batteries are dangerous because of their chemistry. Deadly dangerous. There is no danger in swallowing Lego heads. Which was the point. Be aware of what’s actually going to harm your kid.
We had a teen swallow a coin cell and it was allowed to pass. The biggest factors for retrieval seem to be size, a small child may have the object stick, and then if the battery ruptures. The ER doctors seemed satisfied it hadn't done so, and sent us on our way.
“ We get people to swallow pill cameras all the time in our gastro department, and they're bigger than that. The numbers that we'd learned, although I'd learned as part of my pediatric training around what you will and won't pass and where the danger zones are, is that if something's greater than 110 millimeters, then it won't get around your duodenum. And if it's pointy and spiky, then there's a risk of it stabbing into stuff. The Lego heads were neither of those. We've kind of talked about that right at the point of designing the study because we talked about swallowing the classic two-by-four Lego brick, and then decided that that was going to be too pointy. Really, a Lego head is just like a piece of corn, isn't it?”
So no, there’s no danger. Sure, the passing time was the premise but this was done for a) laughs and b) to spread awareness about swallowing batteries.
In any case out of annoyance I swallowed some teflon plumbing tape. A few days later I had to take an international flight and, ta-da, excreted it in the aircraft toilet. That was lucky as I had a convenient metal shelf and not a bowl of water. As I had predicted it was intact and perfectly white.
I sent my colleague a photo from my phone. He was annoyed when I got home.
PS: I had been carrying around a cheap disposable pen for this purpose. I stole it from his desk.