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!
Teflon tape for gas connections is yellow.
edit: Or maybe it's for stainless steel pipes?
Is it possible that your co-worker was annoyed mostly because nobody really wants a picture of poop?
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.
Secondly, another comment gives examples of similar tape that isn't white. https://news.ycombinator.com/item?id=34554613
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.
So, I'd file this under "one persons experience is not necessarily a guarantee of universal experience."
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’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.
[https://en.m.wikipedia.org/wiki/Hall–Héroult_process]
And as other people have mentioned, the manufacturing process involves some really nasty chemicals, which often end up leaking out into the environment.
It's PFAS, so he likely got a high load of forever chemicals that are still in him today.
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.
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.
Or breathing pressurized oxygen for that matter? Have a look for oxygen toxicity on Wikipedia.
"This atom is toxic, this one isn't" isn't how chemistry works.
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.
You've refuted nothing.
> I would rather breathe pressurized oxygen, than pressurized fluorine.
Dead either way. Why would you have a preference?
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.
Of course. I also deliberately do not eat apple seeds for the same reason. Do you actively seek to eat toxins?
> Dead either way. Why would you have a preference?
Because one is more likely to kill you than the other. I don't know why you're making this out to be so complicated.
I can't live my life avoiding oxygen. I can live my life avoiding fluorine. Simple as that.
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.
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.
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.
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.
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
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.
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.