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ivthreadp110 t1_j2dg3re wrote

Tetanus is not caused by rust, it just makes a nice environment for the bacteria to live. It usually comes from agricultural runoff. So the rust on a rusty nail is more likely outside whereas the rust on your shaving razor is less likely to have been exposed to animal dung.


wiskey_straight86 t1_j2diorx wrote

I guess I've been shaving wrong


throwaway8u3sH0 t1_j2dk437 wrote

I thought this was the other way to use a poop knife.


Touchtom t1_j2e129z wrote

How to say you e been on Reddit forever without saying you have been on Reddit forever.


ChaoticEvilBobRoss t1_j2enf3v wrote

If you haven't upgraded to the Pooptana yet, then you need more fiber in your diet. Nothing beats taking a poop, then using unsheathe and a heavy attack to cleave that log in two.


Excellent-Practice t1_j2dtq42 wrote

Hijacking the top comment to ask why OP is shaving with a rusty razor. Your face deserves better. Get a new blade


jeffa_jaffa t1_j2e2r5j wrote

How else are we to deal right OP being a drunken sailor?


Any_Werewolf_3691 t1_j2e29br wrote

Stop pushing big razor's agenda. Beards are beautiful. Let's normalize not shaving or only shaving with non disposable blades.


ChaoticEvilBobRoss t1_j2en7ic wrote

I like to shave my face with a sharp piece of shale, or a good shell. Works great and is incredibly reusable.


morosis1982 t1_j2ex049 wrote

Disposable is fine, but it should be the old school type. Have been shaving with a safety razor for a while now and it's superior in every way to a modern one, and a pack of 50 blades is like $10.


DeadFyre t1_j2dqe3w wrote

Specifically, the bacteria Clostridium tetani. It's a benign bacteria which lives in the soil, or in the gut of animals. It's just that inside the bloodstream, in hypoxic conditions, they can produce a toxin.


patrik3031 t1_j2dsc8j wrote

Additionaly the cut depth matters, nicks are less likely to give you tetanus than stepping on a nail.


ohfuckohno t1_j2dvnzu wrote

Also, hijack- if you cut yourself deep enough with a “old/rusty” razor they will still give you a tetanus shot


Pocok5 t1_j2dgde8 wrote

Tetanus is not related to rust. Tetanus lives in the soil outside and only infects you if the object you get stabbed by was outside, exposed to contamination by rain splatter and such. Exposure and rain also happens to make metal rusty. Getting tetanus from a rusty nail outside is correlation not causation. You can also get tetanus from a completely rust free garden tool if you stab yourself with it.


PofanWasTaken t1_j2dngam wrote

Then is it false that rusty weapons were used in war to poison enemies? Is it the same correlation?


Pocok5 t1_j2dplxg wrote

You can stick caltrops in dung so they are more dangerous than "3cm nail in the foot" would ordinarily be. For actual handheld weapons, keeping them in good, sharp condition is kind of a priority, since it's small comfort to know the dude you scratched had a bad time a week after he partitioned your ass like it's Poland. Of course peasant armies often went to war with whatever pokey tool they had, and you can absolutely get tetanus from getting stabbed by a hay fork or a straightened scythe. Against armored opponents, sharp weapons are of little use, so knight vs knight combat would have been maces and hammers mostly, and those don't do deep stab wounds anyway (except war picks and morning stars


PofanWasTaken t1_j2dqm1j wrote

No cure for blunt force trauma eh?

Thanks for the insight


Pocok5 t1_j2ds4ts wrote

Turns out there's only so much padding you can fit in a helmet, so competitive in-situ blacksmithing sessions were the go-to method of settling disputes for a good while.


The_Casual_Scribbler t1_j2dpjzx wrote

The way I understand it is that rust is a good environment for the bacteria so it is more likely to maintain active bacteria better. But I could be wrong lol.


catscausetornadoes t1_j2dgv3h wrote

Tetanus is an anaerobic bacteria. It thrives in deep puncture wounds where there is no air circulation. That’s why they are related to rusty nails in peoples heads, but the rust has nothing to do with it. It’s the deep wound with a small entry point.


snash222 t1_j2fhmi9 wrote

So non-rusty nails in people’s heads is ok?


[deleted] t1_j2dw2ma wrote



Harbinger2001 t1_j2e18uv wrote

That’s my question. Who the hell has a rusty razor?!?


explainlikeimfive-ModTeam t1_j2e7t5r wrote

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fleur_essence t1_j2dgj1c wrote

The difference is how deep the dirty part gets pushed into your tissue. The Clostridium tetani bacterium hates oxygen (air), but is happy like a bug in a rug when introduced to the anaerobic Petri dish that is your tissues under the skin. Doesn’t have to be a nail; getting stabbed with anything that was exposed to dirt could be a problem


[deleted] t1_j2dg0bj wrote



Berek2501 t1_j2dhuh8 wrote

That was my immediate takeaway, too! Everyone else is giving real answers and I'm like r/holup


DrySyllabub2563 OP t1_j2dg7gi wrote

My understanding was that razors go dull due to micro rusting that happens from the wet/dry cycle since your can’t get them ever fully dry.

Could be wrong on that though and my whole understanding of razors is 🤯


Berek2501 t1_j2dhqf1 wrote

No, razors go dull because the hairs will wear down the sharp edge, making it more blunt. Most razors use stainless steel, so if they're rusting on you (rust will be visible), then you're doing something wrong (e.g. using the same disposable blade for too long, not properly drying, etc.)

You should never, ever shave with a rusty blade.


constantino675 t1_j2dusma wrote

You're half right. The biggest contributor to dulling is mineral deposits from drying cycles.

If you dry the blade after every use (including a blast of compressed air) the blades can last 150+ shaves with minimal wear.


Antman013 t1_j2dx9kv wrote

This is EXTREMELY difficult to accomplish, however, and usually only done by folks wanting "bragging rights". So called "century shavers" . . . in a practical sense, there is simply no need to be this fanatical about edge wear on disposable blades.


I have seen what both a safety blade and a straight razor edge look like under an electron scope, and u/Berek2501 is correct. The "edge" is actually a line of "peaks and valleys" which, after contact with your hair, have the tips rounded off or over. Honing is done to "straighten" or realign those peaks and valleys and restore that keen edge. It's quite fascinating to see how "uneven" a truly "straight edge" is under extreme magnification.


explainlikeimfive-ModTeam t1_j2dins6 wrote

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USCanuck t1_j2e0zd6 wrote

Who the hell shaves with a rusty razor?


Inevitable-Jump124 t1_j2e0ils wrote

Friendly reminder that while outside rust is more likely to pose a risk because it’s more likely to have been exposed to the bacteria shaving with a rusty razor still isn’t safe. It can still carry bad bacteria and give you a bad time.


sharrrper t1_j2e1lna wrote

Nothing. The idea that rust itself causes tetanus is a misconception.

Tetanus doesn't come from rust, it comes from things being dirty. It lives in soil. The idea of a "rusty nail" is more indicative that it's been out there in the environment a long time and may have picked up contamination. The rust itself is incidental.

If you get a puncture wound from a non-rusty nail or anything similar out in a field you should also probably get a tetanus shot for that as well.


PckMan t1_j2e285d wrote

Tetanus is caused by bacteria. It's a common misconception that this bacteria is inherently found on rusted metal but that's not true, it's found in soil. We've been taught that getting injured on a rusted piece of metal can cause tetanus because for starters, it's more likely to find rusted metal outside than inside, and secondly, it's more likely that rusted metal will injure you than non rusted metal since generally speaking people don't just leave out sharp or dangerous pieces of metal around, but rusted metal can still cut someone because of how the metal turns from smooth to jagged.

If you get cut on rusted metal at a playground for example it could very well contain tetanus, or a fence, or a sign post, or something like that, because it's outside and driven into soil. Rusted metal that's not come in contact with any possible sources of tetanus bacetria can't just have them because it's rusted.


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CameoAmalthea t1_j2ecs0i wrote

Don’t shave with a rusty razor. As others have said rusty things make have bacteria on them and while things outside like nails will have the bacteria that causes tetanus razors can have other bacteria.

In 2007 at The Excalibur, in Las Vegas, NV. A Las Vegas a woman shaved her legs with a rusty razor blade and got a Group A streptococcal infection, which develops into necrotizing fasciitis ("flesh-eating" bacteria), when she cut herself. The bacteria in her blood stream broke through a wart in her face and started eating away at her face, eventually killing her from sepsis.

Throw out rusty razors.


vegivampTheElder t1_j2dg0gu wrote

Nothing, in the sense that if you get hurt from a rusty nail, you should also get checked for tetanus...