Simple mix of soap and solvent could help destroy ‘forever chemicals’ • Hacker News Board

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

#161

Post by kragen » Fri, Aug 19, 2022, 4:51 AM UTC

fy20 wrote: post #148

kragen wrote: post #91

Earlier quoted context omitted.

Do you have recommendations for seasoning them without a thermostat or a suitable thermometer? I successfully burned my new cast-iron skillet clean, but even after four thin coats of poppyseed and flaxseed oil, each heated up for an hour or so to a temperature that chars garlic skin after a few minutes, eggs still stick if I try to cook them on it without oil. (I'm a fan of teflon but I like cast iron even more.)

I tried many different methods and nothing really worked, then I finally came across this: - heat it up so it's warm in the oven - coat it generously with vegetable oil (it's what I had, but basically any oil will do) - wipe the excess with a paper towel so it's still shiny but not runny - put it in the oven for an hour just above the smoke point of the oil (I'm not really a fan of cast iron, as they are too heavy fo…

How do you get it to be just above the smoke point of the oil without a thermostat or a suitable thermometer? The knob on my oven just varies the amount of gas going to the burner.

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

#162

Post by kragen » Fri, Aug 19, 2022, 4:55 AM UTC

chaxor wrote: post #152

kragen wrote: 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.

NaOH is only unsafe because it's highly alkaline, but it doesn't stay highly alkaline after it encounters buffers like bicarbonate or hydrogenphosphate, which are abundant in the natural environment. After it's been neutralized in this way, it's just sodium ions, and while enough of those will indeed cause environmental damage (witness salinization-induced desertification in much of the Middle East) it takes truly massive quantities.

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

#163

Post by giardini » Fri, Aug 19, 2022, 4:56 AM UTC

1_over_n wrote: post #138

bergenty wrote: post #83

Earlier quoted context omitted.

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

During my masters i used DMSO as a carrier for various lab experiments. The general consensus was to avoid skin contact with it.

This.

I once had a long-running (weeks) experiment that used DMSO as a solvent. Early on it was realized that the DMSO was degrading all non-glass rubbers and plastics in the chemical "circuit", which began to sag like an old TinkerToy structure. Had to rebuild/rerun with parts that were resistant to DMSO.

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

#164

Post by 10u152 » Fri, Aug 19, 2022, 4:57 AM UTC

Infernal wrote: post #150

ngold wrote: post #38

Earlier quoted context omitted.

We just need to boil the world's oceans now

I think it’d be more efficient to simply pump the ocean out of the environment.

"We towed the ship outside the environment"

https://www.youtube.com/watch?v=3m5qxZm_JqM

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

#165

Post by blix » Fri, Aug 19, 2022, 4:58 AM UTC

kragen wrote: post #109

ars wrote: 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.

If asking for scientific research to support claims is witch-burning, truly science literacy is in a sad state.

And I'm not sure I would really consider a "Go Ask Alice" column as peer-reviewed research.

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

#166

Post by rayiner » Fri, Aug 19, 2022, 5:04 AM UTC

kragen wrote: post #146

rayiner wrote: post #121

Earlier quoted context omitted.

Do people cook eggs without oil? Do you use butter or something?

You can definitely fry eggs on teflon without butter or oil or anything. I have this vague memory that I used to be able to do this on cast iron when I lived in the US, with maybe the occasional bit sticking.

But why.

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

#167

Post by kragen » Fri, Aug 19, 2022, 5:08 AM UTC

blix wrote: post #158

ars wrote: post #130

Earlier quoted context omitted.

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…

You're confusing TiO2 with SiO2. There is some interesting evidence suggesting that TiO2 nanoparticles may accumulate in the body, in particular in the pancreas, but there is definitely not a significant body of evidence suggesting that inhaled TiO2 is a carcinogen.

It would be pretty interesting if it turned out that TiO2 added to food as a white colorant were responsible for the obesity pandemic --- the epidemiological correlations are about right --- but so far the evidence that it has any kind of harmful effect at all is fairly weak.

Shards of glass are commonly used as a mild abrasive in toothpaste, an inert excipient in pill formulations, and a gas reducing agent in simethicone; they go by the name "amorphous silica" or "silica gel". They're also added to grains as an insecticide in the form of diatomaceous earth. It's commonly accepted by people who study this stuff that they are absolutely harmless to humans at that size.

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

#168

Post by blix » Fri, Aug 19, 2022, 5:13 AM UTC

kragen wrote: post #167

blix wrote: post #158

Earlier quoted context omitted.

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…

You're confusing TiO2 with SiO2. There is some interesting evidence suggesting that TiO2 nanoparticles may accumulate in the body, in particular in the pancreas, but there is definitely not a significant body of evidence suggesting that inhaled TiO2 is a carcinogen. It would be pretty interesting if it turned out that TiO2 added to food as a white colorant were responsible for the obesity pandemic --- the epidemiolog…

What about larger sizes :) Physical effects can matter as much as chemical. Diatomacious earth has conflicting evidence anyway. Silica gel and glass aren't really the same thing.

I did mean TiO2. There is a reason the EU considers it a carcinogen and is banning it from several classes of products.

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

#169

Post by kragen » Fri, Aug 19, 2022, 5:14 AM UTC

blix wrote: post #165

kragen wrote: post #109

Earlier quoted context omitted.

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.

If asking for scientific research to support claims is witch-burning, truly science literacy is in a sad state. And I'm not sure I would really consider a "Go Ask Alice" column as peer-reviewed research.

But the claim in question is one of the best-known and most thoroughly established claims in all of toxicology. Asking for scientific research supporting the biocompatibility of PTFE is akin to asking for scientific research supporting biological evolution or the claim that people have landed on the moon: it's a sure sign that the person making the demand has a pre-existing flimsy pretext for rejecting literally all the research in the relevant field, which did indeed turn out to be the case; see https://news.ycombinator.com/item?id=32517203.

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

#170

Post by kragen » Fri, Aug 19, 2022, 5:18 AM UTC

blix wrote: post #168

kragen wrote: post #167

Earlier quoted context omitted.

You're confusing TiO2 with SiO2. There is some interesting evidence suggesting that TiO2 nanoparticles may accumulate in the body, in particular in the pancreas, but there is definitely not a significant body of evidence suggesting that inhaled TiO2 is a carcinogen. It would be pretty interesting if it turned out that TiO2 added to food as a white colorant were responsible for the obesity pandemic --- the epidemiolog…

What about larger sizes :) Physical effects can matter as much as chemical. Diatomacious earth has conflicting evidence anyway. Silica gel and glass aren't really the same thing. I did mean TiO2. There is a reason the EU considers it a carcinogen and is banning it from several classes of products.

Silica gel is glass with nanometer-sized pores in it. Bottle glass has additional additives that lower its melting point and increase its solubility (oxides of sodium and calcium).

The EU has irrationally banned all sorts of things since the witch-burners have seized control of the government apparatus. Borate fire retardants and fertilizers is one of my favorite examples.