Does Hand Sanitizer Create Superbugs?

Alcohol-based hand sanitizers are an effective way to kill a myriad of potentially harmful microbes. But is there a risk of germs becoming resistant to this ubiquitous liquid?
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[@Robert-bo9kw]

Antibiotics are like going to a car and cutting the ignition cables, If it happens enough the car manufacturer mightl eventually put those cables in a different location or make getting access to the engine harder for those without the keys. Alcohol based hand sanitizer is like dropping a brick of C4 on the hood and pushing the detonator. Nothing can really prevent that from breaking the car.

[@djoakeydoakey1076]

That's when you mutate into a tank,

[@theist873]

There are explosive-proof cars.

[@kewakl8891]

@@theist873 but what about 16-ton brick-proof cars kzbin.info/www/bejne/pWKWmJ-Iireaiqc

[@lemongavine]

Great analogy

[@rickseiden1]

Your analogy only works to a point. If the antibiotics kill 100% of the "bugs", there are none left to evolve any kind of resistance to it. If you stop taking antibiotics when only 75% of the "bugs" are killed, you've left behind 25% that is more resistant to it. That 25% goes on to breed, and with the genes of the weaker 75% out of the gene pool, future generations are stronger. That's why you have to take the full round of antibiotics. The reason that antibiotics are losing the battle right now is two fold. First, they were over used. Using them when the person wasn't sick helps everything and anything get stronger against them. Second, people stop taking them when they feel better, leaving behind that stronger 25%. (Note that my numbers of 75% and 25% are meaningless numbers thrown out for an example. It could be 99% and 1% or 1% and 99% for all I know. But the fact that some are left behind to breed a stronger generation is the key.)

[@tsalapbeew]

Antibiotics: NO! YOU CAN'T JUST WREAK HAVOK AND DESTROY EVERYTHING! YOU NEED TO LOCATE SPECIFIC PROTEINS AND... 70% Alcohol: HAHA CELL WALL GOES BLORT!

[@prism2451]

Which cell wall?

[@AmazingtristanMagic]

@@prism2451 Or, you know... cell membrane. Either/or.

[@aintnobodylikeu]

LMFAAAAOOAOAOA

[@CellRus]

The key word is "alcohol-based" and not the stuff with added triclosan or similar antibiotics

[@Darxide23]

That stuff is not in sanitizer, it's what's in "antibacterial" hand soap. And the research shows that stuff _never_ worked and is actually more harmful than anything. It gets in the water and kills fish and other stuff.

[@metamorphicorder]

@@Darxide23 thank you. We found the chemophobe and we found someone who actually reaearched stuff. Was comming here to say this.

[@ShirokiMaki]

Bacteria growing immunity to alcohol is like human growing immunity to bomb explosions

[@matttube9369]

Good analogy thanks

[@sidharthravva2561]

Wouldn't lava be more correct word?

[@sebastianelytron8450]

I used to be addicted to hand sanitizer. But I'm clean now.

[@hurhurhurhurhruhrurh]

Sebastian Elytron stolen from reddit. Non-original boi!

[@WG55]

I used to get high off of brake fluid, but I had to stop.

[@Darxcalibur777]

Tyler you’re not paying him to be original, yeah that’s what I thought

[@therobot1080]

This is cring

[@Hobbes4ever]

now you boil your hands in hot water

[@6900xx]

Coronavirus: I'm inevitable!! Alcoholics : *you dare oppose me mortal*

[@qwertyuiopgarth]

Soap and water whenever possible. Alcohol when soap and water are not available.

[@CarloCopier]

Exactly! I really don't understand why they didn't put that in this episode; it's crucial information. If used incorrectly, hand sanitizer can actually help spread the virus, because alcohol does damage to your skin, potentially making you vulnerable.

[@sirBrouwer]

and with both if not a problem use some hand lotion after every wash. your hands will thank you with less creaking.

[@Ikajo]

@@sirBrouwer Most hand sanitizers contain agents to re-moisturize the skin... the real problem can be upsetting your natural balance of your skin. Making otherwise harmless bacteria harmful but even that is not such a big deal.

[@sirBrouwer]

@@Ikajo well the most I encounter are just water with alcohol and some thickening agent. they work good but they dry out the skin way to fast. especially if you have to use it multiple times with in a hour.

[@lemongavine]

Don’t use soap with Triclosan antibiotic.....bugs will become resistant to it. Just use regular soap.

[@FuturologyChannel]

Incredible how such simple products can destroy the most deadly microbes.

[@matteofabbris7877]

try CO

[@voguedictatinglove2455]

Because it can also kill us lol

[@FuturologyChannel]

​@@voguedictatinglove2455 Haha yeah, alcohol is some ironic stuff.

[@tylerpeterson4726]

Definitely an area where KISS holds true. Why try and irreversibly bind to an enzyme when you can just mess with intermolecular bonding. Also the reason why you can't cure pneumonia by going on a week long bender, because it'll destroy you too.

[@jeremyolson6419]

Hi disinfection chemist here! I live in Canada, so the regulations might be a little bit different in the US. But up here anyway there are no straight alcohol hand sanitizers, it doesn't kill a broad enough spectrum of microorganisms to qualify as a "disinfectant". So typically they are spiked with another chemical that does have the ability to murder things like fungal spores, the most common of which are "quats" or quaternary ammonium compounds. These are added at a similar rate to "classic" antibiotics (on the order of 100s of mg/L). They are pretty sturdy molecules that have a broad spectrum of action, but I personally am a little worried about bacteria evolving a response to them.

[@corwinweber693]

That's why it's a sanitizer, not a disinfectant. Under US law, (if I remember right) a sanitizer kills 99.9 percent of microbes. A disinfectant kills 99.99 percent. Sterilization kills everything, and so far as I know there are no chemical products that can do it. You usually need heat, ionizing radiation, or both. (So, an autoclave is the easiest, and you usually don't see actual sterilization outside of a lab or clinical environment.) That having been said a fair number of our sanitizers and disinfectants are also mixtures. Quats are a little hard to find in this country sometimes, but there are products like Listerine that have a mixture of alcohol and phenols. (Thymol specifically.)

[@lordgarion514]

@@corwinweber693 I've worked at several restaurants that used a quat disinfectant spray for surfaces. Some commercial food delivery companies sell to individuals.

[@aerialinterimmanager]

What about hibiclens?

[@corwinweber693]

@@aerialinterimmanager I don't actually remember what's in that, it's not the easiest stuff to find in the US but it's not unknown. I just googled it, it's got chlorhexidine glutomate in it, so that's not a quat and I'm pretty sure it's not one of the phenols. Just a general broad spectrum germ killer.

[@goodman854]

I only see one medical ingredient on my Hand Sanitizer bottle (ethyl alcohol). I'm in Canada. Not sure how you'd say it doesn't kill enough microorganisms as it kills most all common ones.

[@ezachleewright2309]

1:02 Wait, wait, wait... are you telling me... that booze is bad for my cells? SAY IT AIN'T SO, DOC!!

[@sanitysquota937]

THANK YOU!!!!!!!!!!!!!!!! I was one of the people worrying about this! I will sleep more soundly knowing my concerns were unfounded. This is one of the many reasons I love scishow!

[@fastfiddler1625]

I've heard this one so many times. I am surprised though that you didn't address the correct side of this story. The idea of "super bugs" isn't a fallacy, but it's also not alcohol based sanitizers doing this; it's antibacterials in antibacterial soaps. First off, it's kind of a redundant process and if you are washing your hands correctly, most viruses and bacteria are either destroyed or washed away. In fact, in 2016, the FDA banned the use of many common antibacterials like triclosan that were used in soaps, for example.

[@curties]

soap with antibiotics... cant imagine why we find so much of that stuff in water xD

[@matteofabbris7877]

make a microcosmos episode where you use alcohol on bacteria

[@motherteresa8418]

What if bactira build a wall what if evolution isn't random mutations like Darwin says and more of gene Expression like Jean Bathist lamark said

[@Awkward_Fox]

With how KZbin is going, I wouldn't be surprised if a video like that got demonetized for "the ruthless killing of a defenseless being" or something along those lines...

[@358itachi]

Do you want to see a massacre so badly?

[@williamlowry6492]

@@motherteresa8418 Thank you for your widsom Mother Theresa

[@Exdorme]

@@motherteresa8418 than cat would rule the world already

[@Seadalgo]

One of my undergrad students' favourite lesson blocks was the broad overview of antibiotics. The mechanism of action of B-Lactam, Transpeptidase inhibitors, macrolides, aminoglycosides, Glycopeptides, RNA translation blockers, DNA action/Quinolones, PABA analog antifolates/Sulfa Drugs, etc.. I've had students that just took the class as an elective tell me the lesson block always stuck with them because they were amazed at how many different ways a problem could be approached from.

[@claudiakinuthia6261]

Amazing! Keep up the extremely extravagant work, SciShow!

[@zeryphex]

This answered so many questions! Thanks, Mr. Green!

[@jeremyfisher1833]

God how amazing is it that such knowledge is just given to the public for FREE and with such credibility that schools use their videos in all classes from philosophy, to biology to physics' to history

[@Digitalhunny]

Thank you _so_ much for all your fantastic educational videos!! This particular video completely answered a family chat we all had last week. Your time & hard work is doing great things. Love you all. 🤗💖🥂

[@AuntBibby]

2:50 “well, as long as The Scientists *don’t think that’s very likely* to happen, then we’ll be ok.” -person whose survival depends on darwinian evolution being *bad* at adaptation

[@jimmyjames7720]

Thank you guys so much for the steady flow of science-based information. With this day of misinformation everywhere it is great to have you guys.

[@ronik24]

Thanks for the video! :-) There is one thing to consider, as studies have shown, how desinfectants may lead to more danger: for example hospital rooms that have been too radically desinfected may be host to more dangerous bacteria as a healthy microbial environment also keeps all kinds of bacteria at bay. So, destroying these helpful microbes might be counterproductive.

[@lennysmileyface]

I think that the solution is to instead seed hospitals with harmless bacteria. I don't know if that would work though.

[@lennysmileyface]

Or perhaps we need to put money into research for bacteriophage cleaning products, that would be cool.

[@peperonitoni441]

That sounds about right. IIRC, many of the currently known antibiotic resistant, disease causing microbes that we know of are found mostly, if not exclusively, in hospitals. It would make sense if the lack of more normal microbiomes is at least a large part of why they live in hospitals more often than not. The caveat there is that we don't really have a way of selectively targeting the more dangerous bacteria. A sterile environment is much better than a non-sterile one, as basically the past century of medical history has shown. Until science can find a way to more selectively target unwanted and dangerous microbes while allowing the benign and beneficial ones to live on, the best we can do is to disinfect frequently enough to minimize the risk.

[@RWMAirgunsmithing]

That is not how viral loads function on non living surfaces. You are confusing your microbiome with a counter surface, there is no way to control what "good bacteria" will be on the walls in a hospital, there is no way to feasibly manage a proper community of viruses, bacteria and other microorganisms to ensure safety. Hospitals are supposed to rotate their cleaning products in critical areas to ensure continued effectiveness in their protocols and those products that get rotated are usually for spores, not viruses or bacteria.

[@Beryllahawk]

What does bleach do to cells then? Also, re: denaturation - this is also why marinades that involve wine, beer, or liquor work really well; the alcohol "opens up" the muscle cells in the meat, allowing in more salt and other molecules (in other words, flavor)!

[@rusdanibudiwicaksono1879]

Bleach did what bleach do, _oxidizing everything._ Or, if you put it into song, _Do you believe in magic in a young girl's heart_ 🎶 _How the music can free her, whenever it starts_ 🎶 _And it's magic, if the music is groovy_ 🎶 _It makes you feel happy like an old-time movie_ 🎶

[@NikhoPrasetyoPratama]

They make some tiktok user to hospital..

[@TheTJDONALDSON]

Karens of the world: The solution is essential oils.

[@djoakeydoakey1076]

That's not funny, I want to speak to your manager!

[@Hawkenshmire]

I think u mean either scammers or ppl who think home remedies work. Karens are just piss offs.

[@Hobbes4ever]

who the f is Karen

[@fredericapanon207]

@@Hobbes4ever a name for overly entitled people that was first popularised on Reddit. Also mentioned frequently on Not Always Right, a site about customer service horror stories. Karens get validation from treating service people atrociously.

[@Eclyptical]

I'm so glad you mentioned the 2018 study! I read it a while ago and, as you mentioned, made the false assumption that it meant that bacteria could build tolerance to alcohol-based handrubs. Glad to know now that it's extremely unlikely.

[@mnoxman]

Should make an update to include Peroxide (3, 7, 12%)

[@TheDavidlloydjones]

"Does Hand Sanitizer Create Superbugs?" No. The superbugs created the hand sanitizer. They want to keep the regular bugs off their hands.

[@motherteresa8418]

What I bacteria build wall to block it. . What. If Evolution doesn't work by random mutations

[@Nw-zh1uq]

@@motherteresa8418 The only walls that can protect it are walls that are not made of lipids,proteins or even carbohydrates alcohol burns and splices almost everything.

[@Y2Kvids]

Wi

[@LaiPt]

lol

[@Sriharshabhogi]

Thanks for the informative video. This cleared some of my assumptions.

[@vopall]

Very helpful. Keep up the good work guys

[@surendrandevaraj9016]

Very happy to see u green.Looks same as like the green in CC, even after years....

[@l96ai]

"And scientists don't think that's very likely to happen" Murphy's law: let me introduce myself

[@theist873]

Also murphy's law: When it happens, it will happen at the worst time possible, with the worst microbe possible, and in the worst place possible.

[@shanam.7342]

But have you ever heard of Cole’s Law? It’s thinly sliced cabbage

[@StrohZwerg]

@@theist873 that's not really what murphy's law says.. it's just if it's possible to happen, it will happen eventually, given enough (or nearing infinite) time.

[@BrianHutzellMusic]

Don't forget: Murphy was an optimist!

[@lasse1106]

0:27 sounds like a strong argument against drinking if you ask me

[@Duncan_Idaho_Potato]

Sodium hypochlorite, AKA bleach, has the same "shotgun blast to the head"-like effect on microbes. You shouldn't use it on your skin (duh) but it's definitely an effective sanitizer on doorknobs and countertops and such.

[@corwinweber693]

I think you actually can in low concentrations, but alcohol is a lot less toxic and doesn't damage textiles that you're probably wearing. But a weak bleach solution would probably work in a pinch. (Assuming you have the bleach and don't have alcohol.)

[@animefreak5757]

@@corwinweber693 it's actually the recommended option in some cases. My sister in law used to run a small daycare in the house, and a half teaspoon of bleach in a spray bottle full of water was what the regulations called for. It works, it's cheap, and there's no bleach shortage. Imo the people paying 30 bucks for a bottle of 70% iso are suckers. People are also way overusing hand sanitizer, it'd be a lot cheaper right now if people used soap and water (just as effective) where it is practical to do so.

[@shellyrae777]

It does age your skin though. I’ve consistently been using aloe purell since I was diagnosed with immune issues a few years ago. Now my skin looks 20 years older! I wish I used more lotion along the way.

[@timperry6948]

How long have you been using it? Twenty years?

[@saucyyikers3877]

@@timperry6948 good point there

[@fredericapanon207]

Lots of vitamin E in aloe vera

[@santiagobenites]

@@timperry6948 She said that she started using Purell sanitizer 'a few years ago', but don't let that stop you from attempting to be funny.

[@RWMAirgunsmithing]

@@santiagobenites Still anecdotal at best xD

[@AbooRasta]

germs adapting to resist alcohol is like fish evolving to swim in lava...

[@rusdanibudiwicaksono1879]

Lava Eel! 🤣🤣🤣

[@Kanpuriye]

I feel like I need to use one right now (the bottle is standing peacefully on the table next to me)

[@candycemonroe7345]

Yep, just came in from outside and need some, too.

[@ballpython3310]

@Marco Polo look up bacteria in soap.

[@DJRAJEE]

Lol idiot

[@lordgarion514]

@@ballpython3310 Irrelevant TBH. Soap only kills some things, but it removes things it doesn't kill as good or better than all those other hand sanitizers the FDA finally got rid of because of the side affects, while being no better than plain soap at reducing the number of living things on your skin.

[@akumaking1]

TL;DW answer: No. There, that's the two-second answer everyone needs.

[@TravisRichey]

Ahhh, thank you!! I was wondering this exact thing, and assumed it was an issue. Thank you for challenging my preconceptions with data and information! I will adjust my practices accordingly. Also, I love that you were talking about bacteria and I was like, "what about--" and then you said "Also some viruses like COVID-19". Brilliant as always. ~Trav

[@marksimmonds6364]

Hank, I would love to see this on the Microcosmos channel. Maybe seeing James try out different concentrations of alcohol on some organisms under the microscope and see how they fare.

[@UnTipoSinNombre]

Thanks for clarifying this to me.

[@frikativos]

I thought you were coming with more "good news, everyone". I am glad they are actually good news.

[@sirBrouwer]

he is no Hubert J Farnsworth

[@inkfree8297]

I've noticed that a lot of places I've had to go to get groceries would have sanitizers but they're watered down (likely because shop owners decided to cut cost and they don't know how alcohol-based sanitizers work). Then I remembered this video and decided to bring my own small bottle of sanitizers should the need to go to a store rises. I wish this was more common knowledge.

[@dragon3085]

It would be great to see a similar video on how bleach works as a sanitizer and the chemistry behind why dilution of the bleach is actually an important step in the process vs just using pure bleach.

[@antiisocial]

Good to know. Thank you

[@speedyjay6255]

Washing hands is always a priority! Use hand sanitizer when there is little to no access to a sink and soap!

[@sirBrouwer]

for my work i have to use both. first wash my hands with water and soap. after drying with a paper towel i have to use hand gel. But then i work at a wild life animal shelter. (reptiles, amphibians and arthropods)

[@speedyjay6255]

@@sirBrouwer i do the same when I'm out in public

[@sirBrouwer]

@@speedyjay6255 if you are out and about please be kind to your hands and add some lotion in the mix. i can't do to the animals (especially the amphibians)

[@speedyjay6255]

@@sirBrouwer i make sure to do that too, my hands are really dry on their own

[@killuminatepeacefulness3948]

When I think of super bugs, I think of a ant with a Cape and a mask

[@katumispencer]

Atom Ant!

[@wenjizeng89]

that's like asking if bacteria will develop resistance to fire

[@motherteresa8418]

Or nuclear radiation Some have.

[@therobot1080]

Some bacteria live in nuclear reactors

[@BasicScienceSeries]

A very important topic to discuss since sanitizers are being used left and right! Good Job Fellows...

[@crazyprayingmantis5596]

Add Raspberry cordial to hand sanitizer, it tastes delicious. Hey, don't knock it till you try it.

[@corwinweber693]

So what DID you do to end up in a Russian prison?

[@crazyprayingmantis5596]

@@corwinweber693 J walked

[@miraadi97]

70%con can be used as bactericidal , fungicidal and viricidal

[@MegaAwesomeNick]

Also we have been fermenting alcohol for millennia with yeast and even they haven't grown resistant to alcohol and they make the stuff.

[@PsychoSocialCreation]

So gooood! Love the explanation super bugsb

[@apgibbs9]

I haven’t heard much about the potential of alcohol sanitizers to contribute to bacterial transformations. I would love to know if that is of concern. I was under the impression that is why hand washing with soap is preferable whenever possible and why peroxides are a better choice for surface disinfectant. ???

[@Shadow1Yaz]

I called it! Though I knew how alcohol based sanitizers work before hand.

[@Allthingsmarinelife]

Super bugs ? Like the murder hornets?

[@calebcrawford3389]

Not quite

[@HenchHerbivore]

How about a video regarding factory farming being breeding grounds for antibiotic-resistant superbugs and how we could be back in the dark ages infections-wise if we don’t stop

[@cantsay]

Can you talk more about Norovirus and cruise ships? When cruise ships stopped using so much hand sanitizer the virus was greatly reduced, they determined it was causrd by using too much hand sanitizer. Can you tell us more and why?

[@Nonunusmultorum]

What about antibacterial hand soap being pushed at the supermarkets?

[@Tmanw8898]

10 years ago when I was 12, I was always scared of that happening from hand sanitizer because I’d see new about anti bacterial soaps, and then I’d shame my sister every time she’d use hand sanitizer, I better go apologize too her now.

[@fredericapanon207]

Hand Sanitizers are different from antibacterial soaps which have antibiotics such as triclosan.

[@yvrelna]

Note that there are hand sanitizers that contains antibacterials. Those should be avoided to use regularly. Regular hand sanitizers that only contains alcohol and water are good enough for most purposes without running the risks of creating superbugs.

[@dutchik5107]

@@yvrelna well. Also some like gel. Like glycerol or something But that's more a comfort and skin not falling off long term thing

[@Hobbes4ever]

most of us were stupid when we were 12 :D

[@petersmythe6462]

Also the very extensive adaptations for an organism to survive in ethanol, and there are certainly some that can, do not help these extremophiles live in you. They require severe compromises. Like making a tank that can fly or an airplane that cannon shells just bounce off of sort of compromises. From the point of view of infecting a living animal, this is not a design compromise you can afford as a bacterium.

[@EmilyParagraph]

As a restaurant worker, yes your hands will crack and peel and be gross using alcohol sanitizers, but if it's good enough for a "front line essential" worker, it's more than good enough for you "civilians" Also don't call restaurant workers "front line essential" we're only there bc yall insist on not cooking for yourselves

[@jay-5061]

Ef Pendergraft what about doctors? They can’t cook for themselves after 72 hours of work

[@JamesWest_III]

Calm yourself. Us “civilians” are the ones keeping your dumb ass employed...

[@kiroropupper3914]

Actually y'all are working because we can't completely shut down the economy. There has to be cash flow somewhere. Sorry you got the short end of the stick but be glad you haven't lost your job.

[@animefreak5757]

@@kiroropupper3914 yea, i'm super glad i didn't get laid off. I get to deal with 3x the customers with less staff (since people occasionally get sick..and now need to take 2 weeks off), and while i'm busting my ass i get 0 protection from the virus at work (the only thing we get are stickers\signs and told to wash our hands often) and no extra pay. Meanwhile my customers are chilling at home, coming into the store to buy some car wash, or some paint to fix a scratch (very essential things apparently). At least one guy came in while under quarantine (he was the only one arrogant enough to admit it openly). These are the people getting more money in EI and support payments then i make busting my ass. Yup, working is just fine and dandy these days. When i get home exhausted and have no energy to fix my own car people are living it up on paid vacation (that's how they treat it) I'm so glad i wasn't laid off, collecting fat cheques and doing stuff for fun.

[@niveusnimbus]

@@animefreak5757 so quit your job. If you're that miserable, do something about it, rather than moan to the Internet.

[@adamstevens5518]

If alcohol based hand sanitizers indiscriminately kill bacteria, does it also kill the good and neutral bacteria? Does this leave the hand exposed for easier recontamination?

[@HappyGick]

It can even kill your own cells, that's why you shouldn't go nuts with handwashing, you can actually make it worse. You need to wash your hands, but washing them too much can even peel off your skin, and thus allowing worse infections to come in. So yeah, they can kill good and neutral bacteria, but shouldn't kill them all if you don't go overboard on sanitizing and handwashing. That's why TV ads about soap tend to say 99.9% of all bacteria, because killing all of them is more dangerous than killing _almost_ all of them.

[@Thumbsupurbum]

@@HappyGick True, but that would be A LOT of hand washing. Your skin cells are already dead, so you're not really damaging anything. Excessive washing can shed the dead layers faster yes expose the more tender skin underneath. But that's not going to be an issue unless we're talking about hundreds of hand washings per day. Even surgeons don't wash their hands that much. I just wanted to make it clear that washing your hands tens of times per day for the duration of this pandemic is not going to cause anyone any harm. If it did, doctors and nurses would have noticed themselves long before now.

[@wongwanchap]

Yes, I always sanitize my query before pass to my database.

[@apeller3629]

Wondering if the situation would have an effect on general public common immune system? As in, common cold kind of things we are regularly building tolerance to I guess. I'm, of course, fuzzy on almost the entire subject but my little understanding is that day to to exposure of bacteria and humans gives the basics of immunity? Maybe I'm completely off but was curious how the isolation time might interact with that, if at all. Thanks for all your videos!

[@IRex-wm9pd]

Follow up question: how long do they stay potent? I have old bottles of hand sanitizer from work related events that I took home because they were just going to get thrown out otherwise. When this pandemic hit I remember thinking wow I have like 15 bottles of hand sanitizer stashed away! Im set! Then I realized most of them were older then a year old. Does the alcohol dissipate over time and if so how quickly?

[@corwinweber693]

It does, but I think if you keep the bottle closed you should be ok. Conventional wisdom says use it within 2-3 years. Most will have a use by date on the bottle. After that it shouldn't be dangerous or toxic or anything, but yes, it might have had enough alcohol evaporate to not be as effective anymore.

[@zappyapp]

Ah thank you, I was gonna stop drinking these sand sanitizers

[@Bruno-cb5gk]

Antibiotics are like bullets. Superbugs have bulletproof vests. Alcohol is like a nuke.

[@gabriel300010]

and some bacterias hunker down in bunkers. which is good, since they cant harm us from there

[@happymevids]

I thought that alcohol was ineffective against clostridium difficile (c diff) spores? Surely this would create an environment in which c diff could proliferate due to decreased competition.

[@darthhodges]

Remember, all the things alcohol does to microbes it also does to your cells when you drink it. If you want to keep those cells alive keep your concentration down, or just don't drink.

[@terrendously]

Hi SciShow, I'm curious about reports of 5x more strokes in the under 50 population in NYC lately due to coronavirus. How serious is the risk to the young?

[@gardenhead92]

Also to be clear alcohol doesn’t just kill bacteria, but eukaryotic cells as well, eg humans. That’s why it can only be used on the surface of the skin and not as a medication to cure infections.

[@sephicloczo6294]

lol, thank you.

[@sanyo_neezy]

You should have added a quick tutorial on how to properly use hand sanitizer, because most people use way too little for it to be effective!

[@IceMetalPunk]

One question is why it doesn't kill our own cells when we use it, since our cells have a phospholipid bilayer as well? Or does it kill our cells, it's just that there are far fewer bacterial cells than our own, so the harm to us is smaller?

[@Thumbsupurbum]

You can't kill what is already dead. The outer layer of your skin is already dead. So no you're not going to damage them. Excessive hand washing can lead to shedding those layers faster than normal, but there isn't really any risk to you so long as the product is used properly.

[@TheSwarm666X]

how about Benzalkonium Chloride?

[@RichardRagan]

Should have mentioned that endospores can be killed by hydrogen peroxide that's why the World Health Organization recommends 70% alcohol and 3% hydrogen peroxide

[@rusdanibudiwicaksono1879]

"Sir, they holed up and we can't get them!" "...Get me the flamethrower."

[@monalisasingh2331]

Can you please do a video on how good hygiene practices have saved millions over the centuries and can potentially save millions more with the right awareness and reach? I have seen some people keep bad hygiene in name of building immunity.

[@cfromnowhere]

I already know the answer is no, but I still come to watch Hank.😁

[@cipherxen2]

Be kind, sanitize

[@nikkiwilliamson4665]

Does that breaking down of cell membranes and proteins also happen to our skin cells? Is that why it makes skin so dry?

[@RWMAirgunsmithing]

Yes, and probably doesnt help.

[@ryaeon9793]

and.. too much hygiene is bad too.. your body didn know bad stuff because you always kill them. so no 5 second law for food to you.

[@MrKen59]

Imagine what alcohol does in our body when we pour vodka or whiskey in our mouth. 🤓

[@IXONE]

me: **spray hand sanitizer** my mind: 3:58

[@thelaughinghyenas8465]

It's not a bad mix with Cherry Coke either. You can even clump up and extract the soapy stuff with salt and a cloth filter.

I'm telling you something I see with my own eyes on a larger, insect size, but similar problem: fipronil and flea. In the last decade, the usual fipronil based treatment, which used to kill all flea on my cats and provide quite a few months of flea free life. Now it provides a couple of days until reinfestation occurs. When it used to kill the flea in an hour or so and I could not see any moving insect anymore, now some are dead and some are still joyfully jumping around. I cannot increase the dosage anymore as it would become dangerous to the treated animal. (For whom does not know exactly what's fipronil, it is a neurotoxic compound that binds to all kinds of nerve cells. Insect, fish or mammal cells are targeted the same.)

[@garylee8132]

Alcohol mixed with vinegar works great, the vinagar reduces the harshness of the alcohol and also helps to kill bacteria.

[@uss_04]

Its the equivalent of trying to become immune to Flamethrowers.

[@motherteresa8418]

Some microbes are. It'd probably becoming immune to nuclear radiation

[@mo.6ix]

Well there are some extremophiles who enjoy extreme heat...

[@TaiChiKnees]

Surely the follow up question should be: why doesn't drinking Everclear destroy your insides?

[@Amghannam]

It does..

[@Toshikills]

Amghannam Yes, but I would like to hear about the science behind it.

[@keenanvandermerwe9655]

Anyone know how long you should "wash" with alcohol. Or rather how long it takes for the alcohol to effectively destroy the microbes on your hands?

[@gothicangel160]

God i thought all my microbiology knowledge had gone out the door when i saw this title.

[@yvrelna]

If a headline/video title ends with a question mark, nine out of ten the article body/video will say that the answer is no.

[@jakeullman8651]

How do the cells of our hands withstand the alcohol if it kills the bacteria. Aren't our hands made out of the same cell walls?

[@christelheadington1136]

People seem to confuse sanitizer with sterilizer, disinfectant, antibacterials, germicides....................

[@BardedWyrm]

Many alcohol-based hand sanitizers DO facilitate the transdermal absorption of BPA, however. Which is...not great.

[@JohnnyWalkerKat]

So lets make antibiotics with alcohol!!! Mind blown!!! :P

[@rickseiden1]

Does the alcohol in hand sanitizers destroy the cells on our skin like it does the bacterial cells? I wouldn't think so, because we'd all be waking around with nothing but bones for hands, but the way you described what the alcohol does makes me wonder.

[@a2e5]

Your skin has a layer of pretty tough stuff on the outside called the epidermis, and a lot of that are keratinocytes made mostly of keratin. The outermost part of the epidermis is the stratum corneum you can peel off, and the cells in there are pretty much dead without DNA. They have stuff that bridge them together to become waterproof. When the protein is intended to be tough and insoluble to start with, alcohol doesn't have much to do except getting blocked by it. And when something is already dead you can't really kill it either.

[@rickseiden1]

@@a2e5 That's not exactly what I figured, because I don't know enough to figure something like what you said! That's a great explanation. Thanks!

[@HudaefCares]

I'm liking Hank's hairdo rn.

[@dmac1465]

Give the poor guy a break pplz, everything Hank said was correct, he just maybe forgot to mention that other thing you are thinking of. THANK YOU HANK & SCISCHOW! also who disliked this, and what for?

[@lamdawave]

What about the common disinfectant Dettol?

[@corwinweber693]

I'm not sure if it kills this kind of virus or not. Dettol is a phenol I think, roughly analogous to old school Lysol in the US. (Dettol is almost unknown here, I think you can get it when you get way north, some towns that are close enough to Canada that you can easily cross the border and get it. It just never has been a thing in the US, it's pretty much always been a UK thing, although to be fair, the old school Lysol in the brown bottle is getting hard to come by these days as well. Lysol has been making quats these days instead.) Honestly, phenols are a little caustic, they stain, and they stink. Probably best off going with ethanol.

[@lamdawave]

@@corwinweber693 its chemical name is chloroxylenol C8H9OCl.

[@richardpowell4281]

Serious Question, my skin is also cells... So am I damaging my skin when I use lots of hand sanitizer?

[@rusdanibudiwicaksono1879]

Oh, definitely. Luckily you usually notices it before it became permanent. Like, 'my skin became unnaturally dry and sensitive' stuff, 'there's crazy blister develop in my skin' stuff. Perks of being multicellular organism, I guess.

[@darkninja___]

Richard Powell The outer layer of your skin is made of dead cells full of a tough protein called keratin. If it damages those cells, they are already dead and can be replaced. Real damage only happens if you overdo it.

[@Epicmonk117]

Hey how effective would high-pH hand sanitizers be? A week or two ago, you mentioned that caterpillars lack a gut microbiome because their digestive juices were so basic. Could that same principle be applied to disinfectants? EDIT: did I just invent soap?

[@fairydustcryptid]

You just invented bleach

[@rusdanibudiwicaksono1879]

Yes, yes you are. 😉

[@Epicmonk117]

Morgan Fairydust ok

[@SameLif3]

Me no use sanitizer me use shpiiit on hand 🖐

[@prfm_setya95]

AAAH finally somebody make video about this topic 😇🤘