Personal care products disrupt the human oxidation field | Hacker News Reader

Personal care products disrupt the human oxidation field

science.org

205 pointsXzetaU8154 comments

This article has a headline engineered with shock value connotations, but when you read it carefully, it takes pains to rein the suggestions of the title in as much as possible while still stirring the pot. It’s a kind of artistry you need to get papers published these days.

All that aside, it’s an interesting thing to think about but it’s not a basis for any kind of personal health recommendation and the authors state that. I have relevant expertise and this is a very complicated area that people routinely want to be boiled down into black and white simple advice. What this article seems to say is that lotion can affect the oxidation chemistry nearby it, but it’s not yet known if that is an effect with consequences that are on the whole negative or positive.

I would criticize the authors for their use of the word disrupt, because of the negative connotation carried by that word when talking about human biological systems. They use a softer, more neutral word, perturb, to express the same idea later in the article, which I think better expresses the idea without an emotional tinge to it.

Just posting to not just upvote, but also say that you have a very calm thought process and write with clarity

"A commercial lotion composed of aqua, glycerin, Brassica campestris seed oil, Butyrospermum parkii butter, ceteareth-12, ceteareth-20, cetearyl alcohol, ethylhexyl stearate, Simmondsia chinensis seed oil, tocopherol, caprylyl glycol, citric acid, sodium hydroxide, acrylates/C10-30 alkyl acrylate crosspolymer, sodium gluconate, and phenoxyethanol was chosen for this experiment."

Personal health recommendation: You'd be better off rubbing down with olive oil or sunflower oil than with that concoction, most likely. The ancient Greeks got some things right.

> Personal health recommendation: You'd be better off rubbing down with olive oil or sunflower oil than with that concoction, most likely

What evidence can you point to that supports this "most likely" assertion that isn't purely naturalistic fallacy?

> The ancient Greeks got some things right.

The pantheon of capricious gods living on mount olympus? Harvesting the sweat of wrestlers to use as treatment for genital warts?

> What evidence can you point to that supports this "most likely" assertion that isn't purely naturalistic fallacy?

Reducing this to the naturalistic fallacy is inappropriate.

Notice the commenter said "most likely". He's using a heuristic. When we are working with incomplete knowledge (e.g. lack of studies on phenoxyethanol), naturalism is a useful probabilistic heuristic because we are /generally/ adapted to what was in our ancestral environment. It's also a useful heuristic to defer to things we have a significant amount of understanding of (olive oil) than things we have little understanding of (a concoction invented in the 2010s).

When we say "natural", by the way, we are approximately referring to what humans adapted to by natural selection. Eating large amounts of cyanide isn't "natural" just because it's in nature; that's semantic confusion.

No one objects to saying a zoo animal should be eating its "natural" diet, and that its enclosure should represent its "natural" habitat, because this is a generally true useful heuristic. Maybe the apes are going to be healthier if you put them in a VR headset with Half-Life: Alyx and feed them protein shakes -- where's the research? -- but I'm not going to put that on equal footing until the research is out. Until then, I'll go with naturalism.

There are artificial things that are very good for us, such as vaccines. But we know this because we have sufficient research. When we don't have sufficient research, heuristics like naturalism are going to give you better results on average.

>The pantheon of capricious gods living on mount olympus? Harvesting the sweat of wrestlers to use as treatment for genital warts?

He said they got "some" things right. It's implied that they got a lot of other things wrong.

> Reducing this to the naturalistic fallacy is inappropriate.

> Notice the commenter said "most likely". He's using a heuristic.

They are using a purely appeal-to-nature-and-antiquity-without-any-other-justification heuristic. If your objection is that I should have said "appeal to nature and antiquity without any other justification" because you think "naturalistic fallacy" means something else (which it might), then ok let's go with that, but otherwise it's very appropriate.

"Most" likely is a decision about the balance of merit.

Show something beyond "people did it without chemical analysis" that doing one is actually better than doing the other, especially in the way being discussed by the article. Show that rubbing olive oil on your body won't likewise disrupt your oxidation field. Show that the polycyclic aromatic hydrocarbons in olive oil aren't individually disruptive to skin chemistry despite suspected or known links to cancers, cardiovascular disease, and poor fetal development.

> He said they got "some" things right. It's implied that they got a lot of other things wrong.

Picking which things were right and which ones were wrong requires analysis of the merits. They did none of that.

ps. Do we have a reason to call them "he"? I didn't see anything in their profile or comment history.

At this point y’all are just arguing about who’s better at arguing xD

Massage with vegetable oil, usually mixed with some fragrances, had been a widespread practice for many millennia, not only in Ancient Greece, but in most lands around the Mediterranean, which was about as frequent as it would be today to take a shower.

In fact, in the ancient world the main use for vegetable oils was for massage and for perfumes, and not as food.

In the ancient literary sources, there are very few, if any, mentions of vegetable oil used as food, but countless mentions of massage with oil.

Already in the first version of the Gilgamesh Epic, almost 4 millennia ago (the Old Babylonian version), there were 4 pleasures listed as the benefits of being a civilized man as opposed to a savage: making love with a professional woman, eating bread, drinking beer and being massaged with oil (these were used to lure Enkidu into going to a city).

While in later times olive oil was the main oil used for massage, in the Gilgamesh Epic it seems that the oil that was used was sesame oil.

2000 years after Gilgamesh, e.g. in Pliny the Elder, similar accounts were given, i.e. that the main benefit from grapes is drinking wine while the main benefit from olives is being massaged with olive oil, both for pleasure and for a healthy skin.

While massage with olive oil or other vegetable oils was ubiquitous and daily for those who could afford it, for me it is a bit of a mystery how they cleaned themselves after that, in the absence of soap, because I have never seen any mention about this.

> how they cleaned themselves after that

Water (bath), wash cloth or https://en.wikipedia.org/wiki/Strigil

None of those looks effective by itself for not leaving greasy the hands and the rest of the skin.

For thorough washing of clothes and other objects they were using lye, but lye would be too harsh for skin.

Perhaps they were first using earth to absorb most of the oil, which was then removed with the strigil, followed by washing with water.

They could have been using some sort of soap too, we don't really know.

> Massage with vegetable oil, usually mixed with some fragrances, had been a widespread practice for many millennia, not only in Ancient Greece

Fragrances made of what if not volatile chemicals? Did they disrupt the human oxidation field? Did the oil?

Anyway, drinking and bathing in mercury was also widespread practice for millenia from ancient greece to the 20th century. And now we know why so many people died prematurely from mercury poisoning.

Trepanation, bloodletting, smearing animal feces on the skin, all common practices of the ancient world practiced for thousands of years that we now know are generally bad ideas.

If one appeals to age-old widespread practice, that's fallacy. There needs to be more than "people did this for a long time" before we make claims about whether that thing is actually better than modern alternatives. People have a long history of doing stupid things for very long times until something new comes along.

According to TFA, the main culprit for disrupting "the human oxidation field" from the skin care products are the alcohols contained therein.

The massage oils and the perfumes used by the ancients were not alcohol-based, but they contained only vegetable oil and oily extracts from aromatic plants.

From what is described in TFA, the oils and perfumes used in the ancient world would have had a much weaker disruption effect than modern products, if any, because they would have captured less of the hydroxyl radicals, while also generating some radicals themselves, possibly offseting the effects due to the captured radicals.

The various undesirable ancient practices listed by you have existed, but they cannot be considered as widespread or recommended by medical authorities, when compared with massage with oil.

Massage with oil was something as frequent as washing for anyone who would not be considered as poor. Massage with oil was praised as important for a healthy skin by the ancient physicians, e.g. from the Hippocratic tradition, for whom the majority of their advices about hygiene, healthy nutrition and exercises remains as valid today as they were 2500 years ago.

> According to TFA, the main culprit for disrupting "the human oxidation field" from the skin care products are the alcohols contained therein.

Phenoxyethanol is a phenol ether, not an alcohol. Olive oil contains a collection of phenolic acids, which are considered to be more toxic than phenol ethers, not less. We intentionally replace the acid hydrogen with an alkyl group specifically to lower toxicity. We do this because we actually study things like toxicity now, which the ancient Greeks did not.

> but they contained only ... oily extracts from aromatic plants.

Phenoxyethanol is an oily substance also sometimes found in aromatic plants! Green tea and chicory both contain it! People across the planet have been consuming chicory and green tea for thousands of years! (Oh no!)

We use coconut oil for kids’ diapers and as skin moisturizer. The melting point (above room temperature in winter) and skin absorption makes it less greasy to me. And it seems ok and maybe preferable to get the refined organic expeller pressed stuff because it has lower aromatic smell and scratchy particles as the virgin cold pressed stuff at a 3-4$ jar discount.

That exact formula matches “Neutral 0% Body Lotion” from Scandinavia.

The opening paragraph is precisely why so many people have moved to natural ingredient products and fragrance free. Some fragrance makers have new for formulas with “clean” ingredients, but they are still proprietary and come with a “trust us” promise. It’s interesting to see the specifics of what these products can do other than what’s advertised on the tin.

[flagged]

My skin care routine is "I showered in some not-so-distant past" and sunscreen. You hit diminishing returns very quickly. Showering more than once a week has no health benefits, it's just so that other citizens of your overcrowded city wouldn't complain about your natural smell.

Not showering for a week means I have a headache all day. So evidently not everyone is doing it for someone else.

That doesn't sound normal? Why would you get headaches from not showering? Never heard of such a thing.

Could be muscle tension or something helped by the warm water

It's not terribly uncommon. My wife also has it. It's also related to the length of my hair, where longer hair is significantly worse. Presumably it's the oil build up as my hair is extremely oily and fine.

edit: I am fully aware that not washing leads to less oil build up over time, but I have tried and doctors have tried and that boat has sailed.

I'd imagine a hair wash in the sink also does the job when in a hurry then? Do dry shampoos work too, or does it need a wet wash?

Yes, washing the hair in any capacity works. Unsure about dry shampoo.

I see, that's interesting. Initially sounded like a hair weight issue, so by wet washing it you remove enough sebum to not drag on your scalp too hard. But I'm not sure it adds enough weight for it to do that.

I wonder that over time your scalp produces enough of some chemical to give you a headache, and so you need to rinse it away before that happens? Especially since you mention that any wet wash helps, so the chemicals in the shampoo aren't actually relevant for it. Interesting issue though, don't envy you.

Somebody needs to touch grass

But what about dating? The nether regions should be washed in anticipation for certain activities. There are no diminishing returns for that.

Just date people who’ve had a bad case of COVID. Problem solved!

All you need is a modest trauma to the nose in right direction. Bones shifting a bit will cut forever hair-like nerves going from your nose sensors back to brain, effectively making you lose the sense of smell. When asked some doctor friends they confirmed harm is permanent.

Ok, so dont shower, and punch my date in the nose. Got it!

COVID would be better because the sense of taste is also affected.

Sir this is HN. Nobody is dating.

Also sex is a different thing from dating.

When you realize that through most of human history people married because of teenage sex drive or economic necessity rather than emotionally mature relationships, then the whole dating thing loses its appeal really fast.

Also, the smell of sweat of someone attractive turns me on really hard.

> Babe I love it how you naturally smell

> That's great but I just bought a new generic cherry shampoo

some of us exercise, and have oily skin, and break out with acne if we don’t shower right away.

some of us live in hot climates where a cold shower genuinely feels amazing and cools the body down.

some of us enjoy showering daily, because the bed sheets get less dirty that way, which means less laundry to do, and reduces my stress.

some of us are married to a lady and want a happy home life (lol).

a sample size of 1 (you) does not mean it’s true for everyone. Just saying. :)

I worked with someone with your mindset and he smelled horrible in the office to the point where HR had to step in and talk to him about hygiene.

Your returns are nowhere close to diminishing, even for people with close to no physical activity or sweating, people can tell if you haven't showered for a week.

I only use naturally-ocurring radium and free-range poison ivy.

But is the poison ivy ethically sourced?

I'm wondering if you have its informed consent.

I see you are a man of culture.

You're not using mixture of amygdalin from organic apricot kernels, coca leaves mixed with unripe seed pods of opium poppy? Does wonders.

You jest, but there's a ton of people convinced they can use rock alum which is natural and so is better than industrial deodorants which contain aluminium.

My inner chemistry geek weeps.

I'm similarly puzzled by "uncured bacon" which afaik still uses naturally occurring nitrites. How they're allowed to call it uncured when it's clearly still cured is beyond me.

I can't use those aluminum containing antiperspirants at all -- they violently irritate my eyes if I put them on my skin.

The rock alum works better, and I don't think you can get it into a different form. The stuff in deodorant is a different aluminium compound.

"the human health impacts of many such chemicals remain poorly understood"

The effects of ritual bathing (soap, scrubbing with washcloths, etc.) on the skin may also be "poorly understood". Many people also wear regularly-washed clothing.

When I look at the laundry-list of chemicals in personal-care products (soaps, shampoos) (and in foods ... sometimes, wow!) I often wonder how much effort goes into testing all of this gunk.

>When I look at the laundry-list of chemicals in personal-care products I often wonder how much effort goes into testing all of this gunk.

A lot of effort

Good news (sarcasm), they laid off all the people responsible for that.

>> how much effort goes into testing all of this gunk.

> A lot of effort

Into testing the long-term biochemical and environmental consequences? lol no absolutely not. Source: I work in this field.

At least in eu, regulation is present to at least try to ensure that products are quite safe for the customers and for the environment

I think there are no long terms and that’s the case for food as well

Occasionally when I shower I get this vivid vision: a man comes home from hard days work and takes a shower. Grabs his shampoo but only squirts out half of his usual amount because shampoo bottle is empty, he thinks it will be enough but after applying it instantly feels it's not enough, so he grabs his wife's shampoo, squirts the second half and rubs it onto his hair. Few seconds later his hair bursts into fire because different chemicals in two completely different shampoos reacted together. How plausible is this scenario?

I love this website

I am not bald because of hereditary reason but this! :)

This happened to me and the water itself caught on fire somehow

I don't think it's very plausible for shampoo but it's relevant for toothpaste for sensitive teeth. There's are two mechanisms for sensitive teeth, one is to flood the nerve with potassium ions using potassium nitrate, i.e. saltpetre. The other method is to block access to the nerve endings with other chemicals. You could potentially mix toothpaste and get your mouth to warm up slightly.

IIRC ShyNM for Indian market for sealing holes in the enamel, warms up, unmixed of course.

No worries, the stuff in the wife's bottle is the same, just more expensive.

Didn't the Joker contaminate personal care products so they did in a Batman movie?

Could very well happen if his wife's into Monat.

As plausible as a leaf catching fire if it lands on a mouse.

I agree. We should go back to the Roman days when clothes were washed in urine.

Some scin medicines contain Urea. It's not that we're much better.

To add: urine is rich of phosphorus salts. Contained in...washing agents.

Maybe we should. Maybe that's better than global warming.

Heh, is this bad ... who knows? Chemistry, environmental chemistry, and biochemistry are absurdly complex and full of interlocking Chesterton's Fences. But the profit motive means we don't really spend much time looking into them before tearing them down.

Actually it sounds kinda good.

Not sure why you got downvoted. The researchers state:

“If we buy a sofa from major furniture company, it’s tested for harmful emissions before being put on sale. However, when we sit on the sofa, we naturally transform some of these emissions because of the oxidation field we generate,” said lead author Jonathan Williams, who heads the study of organic reactive species at the Max Planck Institute for Chemistry. “This can create many additional compounds in our breathing zone whose properties are not well known or studied. Interestingly, body lotion and perfume both seem to dampen down this effect.”

Which, if you're worried about the effects of unstudied compounds, lotion will help protect you against.

That’s like saying diarrhea will protect you against ingesting unknown poisons. Disrupting natural processes rarely comes without unintended side effects.

Sure, but it depends on what you consider to be "natural processes," and what you don't. The oxidation of sitting on a plastic^W vegan leather couch is not a "natural" process, but sitting on wood probably is. It's also not "natural" to be closed up with the results of that oxidation for most of the day, as most of our evolution happened with plenty of access to fresh air. We definitely have evidence that people were using oils and lotions for much longer than we've had modern synthetic materials or "air-tight" building methods.

The science is definitely still out, but I don't think it's unreasonable to think that inhibiting this reaction might be beneficial.

Unrelated: This is why reading comments is becoming useless. People react to the news without opening the article. Its so annoying.

Related: This article shows an interesting study but it’s hard for me to interpret what does this translate to? I think we should minimize very complex and synthetic products to our bodies. Although sometimes it’s necessary when we harm our body (e.g. long sun bathing sessions)

Cloudflare products disrupt the human ability to read science.org articles. The article text available to me:

>Enable JavaScript and cookies to continue

Turning on JS and doing the captchas just results in more captchas, forever, with no end. I have emailed science.org about this in the past but they only fixed it on the blogs, not the main site.

I have this problem when using the JShelter addon if I enable the privacy switches. Your browser is probably resisting fingerprinting.

That is very curious, because I have both JS and all manners of clientside storage disabled, yet can access the site fine.

I guess maybe my CGNAT IP is reasonably well trusted and that's the difference?

Hint: TLS fingerprinting.

(No problems with accessing this site without JS. You just need to make your client look like one of the officially-sanctioned browsers.)

the internet is being ruined everywhere.

This week I wanted to download some old HN front pages on the command lines and only got "403 sorry"

although I do not get that now

> Although sometimes it’s necessary when we harm our body (e.g. long sun bathing sessions)

Zinc oxide and titanium dioxide are basically crushed rocks that absorb UV and are used in sunscreens.

You get what you pay for

This won’t lead to people using less lotion, but it will lead to fancy lotions adding “OH precursors” as the new science buzzmarketing term

Which is funny since the exact opposite, anti-oxidants, have been a fad to add for the past 20years.

You eat anti-oxidants. So unless you're eating your lotions this isn't related and can't be the opposite.

Skin absorbs. So it's at least partially related.

If an actual nutritionist says you can eat it every monkey in a lab coat knows they can sell it as a lotion with substantially less work than testing something else.

> unless you're eating your lotions

Buddy of mine did research in Milan on common sunscreen ingredients. In a lab, those chemicals didn't tend to cross the dermis.

But put that person in the sun and you find detectable quantities of those chemicals in serum within minutes. Turns out the flushing (i.e. rushing of blood to the skin, in particular, to the surface of the dermis) increases permeability. Nobody really tested those chemicals for intravenous use.

So in a very real sense, you ingest in all but digestion the ingredients in your lotions.

Antioxidant supplements provide no benefit, may even be harmful. See 2007 meta-analysis by Goran Bjelakovic, Dimitrinka Nikolova, Lars Gluud, Rosa G. Simonetti, and Christian Gluud, published in JAMA: “Mortality in Randomized Trials of Antioxidant Supplements for Primary and Secondary Prevention: Systematic Review and Meta-analysis”.

https://jamanetwork.com/journals/jama/article-abstract/20579...

A meta-analysis is just a dilution of facts, in the exact proportion to have homeopathic efficacy.

For a slightly more digestible take, see https://news.uci.edu/2025/05/21/lotions-perfumes-curb-potent...

But really, I wouldn't worry about the result of this study _at all_ in daily life. It's quite surprising to me that this would be the top HN article at the time of this comment.

This sounds like a good thing, in contrast to the doom-and-gloom "scary chemicals!!!11" articles that seem to have flooded journals and news in the recent years. I believe it's basically saying there is an antioxidant effect from lotions and perfumes.

Globally, PCP usage is widespread

Skimmed the article at first, and this made me chuckle. I wonder if that was deliberate.

"I believe it's basically saying there is an antioxidant effect from lotions and perfumes."

Which would be of no value.

There is no mechanism - no pathway - for ingested or applied "antioxidant" delivery into the cell where we believe we see oxidation or damage due to free radicals, etc.

... and even if there were it would probably have a terrible impact because it appears that the oxidation and free-radicals are an essential cell signaling mechanism which triggers apoptosis.

Which is a fancy way of saying: cells use these tools to kill themselves when they are performing badly. You would not want to interrupt this process.[1]

[1] https://en.wikipedia.org/wiki/Power,_Sex,_Suicide

With how bad for us the common fragrances are in regards to things like cancer risk, endocrine disruption, etc, its surprising that nothing has changed. Most products have fragrance free alternatives.

In fact, it was specifically one of those alternatives which was under test here:

“a fragrance-free body lotion containing linoleic acid (Neutral, Unilever body lotion for sensitive skin; 0% colorants and 0% perfume)”

Sounds like they blame the phenoxyethanol? Which serves a preservative kind of role?

Yeah, my comment was just to add that scents have so many other issues than just what's in the article.

This is the first time I'm hearing they are bad. Could you share some research about this?

At least in the eu there are quite strict rules regulating cosmetics. Hell, lilial in perfumes was banned just to stay safe because they couldn't determine an "average exposure" and went on by banning it in perfumes to reduce what would have been the real exposure, even if it wouldn't have caused issues by being used in perfumes standalone (so not how it's used in cleaning products)

They might not be perfect, of course, and they're always improving

Yes of course, there are a ton of bad substances. But I as not aware of something that is. Ubiquitously used, known bad and not banned in the EU.

EU is much better than the US for ingredient safety. I'm not sure of the EU stuff specifically, but it looks like there's still some concerns over some perfume ingredients, if not the fragrance itself. You'll probably have to do more research yourself.

https://taenk.dk/system/files/2022-01/Whats-that-smell-repor...

There's tons more than this, but here's some high level stuff. The most concerning part is that some of the 4000+ fragrances in use are known and suspected carcinogens.

https://health.osu.edu/health/general-health/how-fragrances-...

I once worked for a large consumer goods company. We had a conference about scents.

We saw a clear correlation between richer consumers and a preference for subtler scents or even no scent.

This even applied across countries: third-world consumers liked aggressive floral scents, but in Northern Europe and North America, the scents are way less concentrated and tend to be more toward subtle alpine or linen.

All this was 15-20 years ago; today I notice that no soap in my house smells like anything at all.

I'm a perfume fan (hobbyist? I don't know how to name it), and I wonder if this still holds. Nowadays, the "luxury" brands such as the Arab ones, and even the "western" European niche catering to the biggest spenders are making a lot of oud fragrances, gourmands, incense perfumes... Basically anything thick, dense, almost syrupy. They don't limit to this, of course, but ouds became much more common in the last years

Can you recommend some fragrances or a brand that does some contemporary subtle forresty mossy but also is not crazy expensive posh branding endeavour?

I'm not entirely sure I understood your request, something foresty? Not a lot into those, anyway

Helan vetiver and rum, don't know if it's available in usa. Has a rum note as well as moss, I've definitely heard people around me saying it smells like forest, to me it's more of a mossy scent

Erbolario Periplo, but it's more Mediterranean bushes

Dsquared original wood

Maybe lalique encre Noire or encre Noire sport

I'd suggest to try them before buying them

In Sydney. It has destroyed the olfactory field imo. I cant stand the ambroxan(?)...it smells like IPA on PCP :/

Sauvage is a big ambroxan offender, a cold sharp metallic note that pierces the brains around the person wearing it, who clearly has no brain for damage to be suffered (/s)

80s au saucage? I dont remember that one being like that. Funny.

There's a particular Middle Eastern market I visit where the cash reeks to high hell of cologne.

It turns out a few of the customers douse their dollars with their personal scents to remind everyone who's spending money with them, and I suppose to see where it might be circulating.

Personally, I prefer neutral lotions and detergents because I wear my own cologne. It could be because

It could also be because we’re using more products. If my face moisturizer and sunscreen had different scents, that would be unfortunate. It would limit my options to those that went together.

I don’t normally want my face to smell like anything (again, cologne) but if I did I would choose only one product that’s scented. Probably beard oil.

> today I notice that no soap in my house smells like anything at all.

Same here, and all ja e store branded products certified allergy friendly.

I've noticed it is really, really hard to purchase unscented laundry detergent in certain regions.

Two different Krogers in the same Houston metroplex, one will have only scented slop while the other has no fewer than 3 unscented options front and center.

You can tell just by walking through the neighborhoods what kind of inventory the grocery stores are pushing. The Febreeze infused Tide is like a chemical weapon when put through a clothes dryer. You can smell that stuff for miles.

> Most products have fragrance free alternatives.

That itself is a big change that took a while.

They've been around for a while, but they were harder to find. Even as a kid there was stuff like arm and hammer washing detergent that was scent free. Although now there are at least 5 free and clear choices at the Walmart.

This is why I get outside and sweat every day.

Not well versed in the field, what are the basic implications of this for health?

The article does not come to any health conclusions, just studies the impact on indoor air chemistry.

In the 1970s there was a lot of talk about ‘healthful negative ions’ and a fad for negative ion generators even though many of those also generated hazardous ozone.

Hydroxyl ions are a significant kind of negative ion in the atmosphere and they’re known to be good because they react with and clean out pollutants like methane

https://en.wikipedia.org/wiki/Hydroxyl_radical

https://earthobservatory.nasa.gov/images/144358/detergent-li...

How can something be a negative ion generator without simultaneously being a positive ion generator?

That isn't how chemistry works.

Isosaccharinic acid has the same chemical formula (C6H12O6) as glucose, which isn't acidic. However, they both have the same net charge.

When something is an acid, it dissociates into both a positive ion H+ and negative ion (rest of the molecule)

HA ⇌ H+ + A-

You're right but a lot of times the positive ion is far less reactive and/or more massive than the negative ion. Not so much for OH-. Charge is not the only thing that matters.

Well, in a similar way to how you can't generate a negative ion without simultaneously generating a positive ion... how do you use the negative ion in a reaction without simultaneously using the associated positive ion in the same reaction?

Here's one way

https://en.wikipedia.org/wiki/Ion-exchange_membrane

Another, that you might be interested in, but it's more confusing

https://en.wikipedia.org/wiki/Proton-exchange_membrane

See the figure

https://www.fuelcellstore.com/introduction-ion-exchange-memb...

Each ion of salt participates in a different reaction

FWIU hydrogen plasma in water for hydrolysis would produce OH Hydroxl radicals. (and H2O2, O3 (Ozone), and NO_x).

TIL that Hydroxyl ions bind to methane and thereby clean the air?

Air ioniser: https://en.wikipedia.org/wiki/Air_ioniser :

> A 2018 review found that negative air ions are highly effective in removing particulate matter from air. [6]

But the Ozone. Ozone sanitizes and freshens, but is bad for the lungs at high concentrations.

Here's some more research, since I have a tiny ozone generator in my fridge and I got worried:

Ozone concentrations as low as 70ppb are hazardous when you're exposed to it for several hours [1]. Estimates for Ozone's olfactory threshold aren't trustworthy, since you go nose-blind to it pretty quickly [2], but it seems like it's probably around 20-40ppb before olfactory fatigue sets in [3,4].

My takeaway is that Ozone generators for rooms/basements/etc are definitely a bad idea. The best-cited olfactory thresholds are all in the same order of magnitude as that 8-hour hazard threshold, and with nose-blindness being a significant factor, you just don't want to mess around with that.

Inside a fridge, though? As long as you don't actually smell any ozone when you open the fridge, and you don't just shove your head in the fridge for hours on end, I'd think you're probably fine.

[1]: https://ozonewatch.gsfc.nasa.gov/facts/SH.html [2]: https://www.ecfr.gov/current/title-21/chapter-I/subchapter-H... [3]: https://www.cabidigitallibrary.org/doi/full/10.5555/19602703... [4]: https://spartanwatertreatment.com/ozone-safety/

if only there was a 'Discussion' section in the article, that goes over the basic implication of the study results... if only.

Yeesh, who taught you to debase others.

wow!, we are emiting a potent biocidal gas strait through our skin!.....it explains so much! and ya, O³ is going to chemicaly break almost anything it touches, which will definitly yield some bad to have on you stuff if the precursor is just wrong. also , most definitly there is a wide diference in peoples indidual chemistry, so this phenominon will join many others in waiting for a more nuanced understanding of how human biochemistry works.

This is impossible to read.

limonene, linalool, "parfum" are the scourge of this age

But are great as part of a cannabis strain profile!

Is soap included? I seldom use body soap during a shower. Probably once a quarter, when my SO threatens me with consequences.

I am not a researcher, but I have a simple evolutionary theory that soap was invented in the last few thousand years and became a mass-market product after the beginning of industrialization.

If we survived and evolved without the use of something in the last few million years, then why is that thing needed?

Lots of plants can be used as soap with minimal processing (crush the plant in your hand while rubbing it on something). It’s likely that most of our ancestors used soap and we evolved to expect it. Just like we evolved to eat cooked or ground up food.

jesus

Is your name Richard, by any chance?

> If we survived and evolved without the use of something in the last few million years, then why is that thing needed?

Because we didn't. A lot of people died, actually. From germs. Before we knew about Germ Theory.

I see this same type of stuff when people talk about inductions or cesarean sections. "Well humans didn't need that before, so why do we need it now?" No actually... humans did need that before. Half of all infants died. Humans are unbelievably shit at giving birth.

Turns out, humans are bad at a lot of things. We die A LOT less now. Like... so much less that we can't even conceptualize how much less we're dying so then we start questioning if we need soap.

And, as a fun aside, the reason humans are so shit at giving birth is because of evolution. You ever wonder why seemingly ever other mammal is able to give birth and it's super chill but we just roll over and die in shocking numbers? Yeah, turns out evolving to be one two legs has disastrous consequences.

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