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Simple mix of soap and solvent could help destroy ‘forever chemicals’

science.org

151–160 of 239 posts

Re: Simple mix of soap and solvent could help destroy ‘forever chemicals’

#151

Slightly off topic, I’m keen to dispose of our Teflon frying pan. Does anyone have a good recommendation for an alternative, ideally one that doesn’t take too much “maintenance”? We also have a Teflon milk pan but that is never used at a high tempriture so I’m less concerned about that.

I've found Green Pan's pans to be wonderful replacements for Teflon pans: https://smile.amazon.com/gp/product/B074CVZ7MM

Re: Simple mix of soap and solvent could help destroy ‘forever chemicals’

#152
post #86

Headline is a lie: as we finally find out halfway through the article, it's not soap but lye, sodium hydroxide. The solvent is the fairly nontoxic dimethyl sulfoxide, so both of these are safe to release into the environment. In https://news.ycombinator.com/item?id=32515659 sbierwagen reports that the reaction requires 120-degree temperatures so this isn't suitable for in-situ remediation.

Ummm... What? 120C NaOH does *not* sound safe "to release". I've worked with similar solutions. That stuff eats through so much and it's a pretty scary solution, if at high concentration.

As with everything, It very much depends on the concentration.

Re: Simple mix of soap and solvent could help destroy ‘forever chemicals’

#153

Slightly off topic, I’m keen to dispose of our Teflon frying pan. Does anyone have a good recommendation for an alternative, ideally one that doesn’t take too much “maintenance”? We also have a Teflon milk pan but that is never used at a high tempriture so I’m less concerned about that.

Depends on what worries you. Stainless steel is the least reactive, but higher maintenance. Cast iron, carbon steel and aluminum are all reactive with acidic foods and will leech metals -- plus the acidic food will strip all the seasoning off. I cook with lots of tomatoes, so that rules out all of these for me. Cast iron and carbon steel (to a lesser extent) need to be seasoned to not stick like crazy and to not rust, which involves polymerizing cooking oil onto the surface. The health effects of this polymerized oil is unknown and the oil smoke is not great for indoor air quality. Digesting regular amounts of rust is also another unknown health effect, though iron can accumulate in people with certain genetic disorders.

I think the safest option is stainless steel, and funny enough, Teflon. They are both inert and Teflon is only toxic if you cook on high heat. I keep a Teflon around solely for scrambled eggs and fish on low heat, but they are very doable in a well oiled stainless fry pan as well.

Re: Simple mix of soap and solvent could help destroy ‘forever chemicals’

#154
post #22

Earlier quoted context omitted.

DMSO is not well-behaved. It easily penetrates human skin, and carries solutes with it. Don't touch! "DMSO can cause contaminants, toxins, and medicines to be absorbed through the skin, which may cause unexpected effects. "Because DMSO easily penetrates the skin, substances dissolved in DMSO may be quickly absorbed. Glove selection is important when working with DMSO. Butyl rubber, fluoroelastomer, neoprene, or thick…

To be fair to the op - in chemistry well behaved means - it is more stable than nitroglycerin, less reactive than fluorine and less toxic than dimethylmercury. Aka - won't kill you outright if you are just properly careful.

Sounds like how Australians supposedly call a box jellyfish sting “uncomfortable”

Re: Simple mix of soap and solvent could help destroy ‘forever chemicals’

#155
post #87

Surely the label "forever chemicals" was a bit alarmist if household cleaning goods could break them down...

The same household chemicals (especially at 120 degrees C) would kill all life. They are effectively forever in the environment.

Well, on human timescales, yes. They will eventually subduct into the mantle and be vaporized.

Re: Simple mix of soap and solvent could help destroy ‘forever chemicals’

#157

Earlier quoted context omitted.

That's true, but in and of itself, it's less toxic to humans than ethanol is. It degrades in the environment quite readily, as well. If we were looking for a chemical to deploy at scale to clean up PFAS in existing environments, we could do much worse.

It’s a carrier. It introduces whatever is in it to your bloodstream.

Have heard that many times, but in grad school it was determined orthogonally to any funded/published project, with n>3 subjects of various skin phenotypes, that many super-potent small molecule compounds were not active topically in DMSO even at 100-10000x doses regardless of polarity... Read between the lines of course. Would not trust safety to that observation with any non-fun chemicals but still.

Unrelatedly, microwave assisted reactions in DMSO solvent wete found to have some totally gross failure modes that were a pain to clean up and got banned in the lab

Re: Simple mix of soap and solvent could help destroy ‘forever chemicals’

#158
post #130

Earlier quoted context omitted.

Just one. Not one of those links is a long term study on ingested PTFE coatings.

And you think that ingesting PTFE is somehow worse than an actual PTFE implant? Why you insisting it must be a digestion study? Do you make such requirements for everything you interact with? Has someone done a study on using paper straws? Or plastic plates? Or metal spoons? Do you understand that when you eat PTFE it comes out exactly the same way it went in? Even powerful acids can't do anything to PTFE, what makes…

Titanium is a common biocompatible implant material, widely considered safe in this context. One of the primary benefits of titanium implants is that that they readily form a TiO2 passivation layer. TiO2 is also common in many topical lotions and sunscreen, where it is considered safe.

TiO2 also has a signficant body of evidence demonstrating that it is a carcinogen when inhaled in particulate form. Just because some compound is safe in one context does NOT mean it is safe in all contexts.

> Do you understand that when you eat PTFE it comes out exactly the same way it went in?

I bet if I asked you to eat shards of glass, they would leave your body pretty close to how they went in :) Whether your body would remain unchanged is another question. While this is an extreme example, there are more subtle ways a compound could interact with the body. For instance, glyphosate has long been considered a safe compound because it "leaves the body the way it comes in." However, recent research has revealed substantial evidence that glyphosate may adversely interact with the human microbiome, which is linked to many various health conditions. This is an active thrust of a lot of new medical research that wasn't strongly considered 20 years ago. It is simply not enough to say the compound remains unchanged, the real question is whether the body is unchanged, and the body is pretty complex and our understanding is very incomplete.

It's not clear which version of the scientific method you subscribe to from your posts, but in general proving a negative is ~really, really~ hard. This list of all possible interactions in the human body with arbitrary chemicals is quite long. The list of things that have been 'proven safe' only to be considered unsafe when studied more carefully is quite long. To suggest that our knowlegde of the safety of ~any~ compound is complete is impossible.

Re: Simple mix of soap and solvent could help destroy ‘forever chemicals’

#159
post #109
post #92

Earlier quoted context omitted.

Here you go: https://goaskalice.columbia.edu/answered-questions/fear-tefl... PTFE goes out unchanged from how it was when it went in. It's completely inert. It's even used in implants, so has plenty of long term studies: https://dermnetnz.org/topics/polytetrafluoroethylene-implant https://www.facialplasticsurgerycharlotte.com/content/upload... https://pubmed.ncbi.nlm.nih.gov/26110468/ How many studies are you looking…

I really appreciate you making the effort to debunk the witch-burners; have you thought about doing it in a less ephemeral medium? Your comment will probably be here for a decade or more but nobody will read it after this month.

That said people here are engaged and interested in the topic and will remember. Whereas a blogpost may not get that traction. A Netflix movie maybe.

Re: Simple mix of soap and solvent could help destroy ‘forever chemicals’

#160

The paper: https://www.science.org/doi/10.1126/science.abm8868 The "soap and solvent" is sodium hydroxide (lye) and DMSO at 120 degC. Those are... fairly... well behaved chemicals, but lye is stout stuff and DMSO attacks nitrile gloves. You could imagine a remediation process that uses this process but the combo ain't exactly Dawn dish soap. I'd almost prefer pyroprocessing over it.

About 40 years ago I boarded my horse with an old cowboy who used DMSO as a horse liniment. He had been using it for years any time one of his mounts was worked pretty hard or when someone brought a lame horse to him. He would rub the joints, calves, and thighs of the horse down good with DMSO for a few days and then they were good to go again.

He also used it on his wife. He told me that she had type I diabetes and neuropathy as a result. Her feet were always cold from poor circulation. That was true until he happened to rub her feet one day after treating a horse. Her feet warmed up in minutes and became normal pink again. After that, he used it on her feet and legs since it improved circulation.

You can say what you will about it being reactive and possibly not good for you but she was able to dance again and get back on her horse so it definitely does have some benefit. They did this for at least 30 years and both of them were past 75 years old when they passed away.

Like another poster said, it is used as a carrier for some medications since it pulls them straight into the bloodstream. I don't think it's magic but I also don't think you'll suffer much using it even with bare hands.

As far as lye is concerned, the sodium hydroxide in this paper, you can easily make that yourself with wood ash and water. It is pretty handy if you are tanning hides since the treatment of a raw hide with lye causes the hair to slip right off leaving a smooth skin ready for the next step.

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