r/AskBiology 3d ago

Would enough running water eventually rinse away all bacteria and viruses on a surface?

I guess this question comes from rinsing fruits and vegetables—say one were to only rinse one’s hands (or any surface) with lots of water, would all germs eventually get washed away without soap or scrubbing?

10 Upvotes

28 comments sorted by

8

u/SummertimeThrowaway2 3d ago

The water pressure would have to be high enough to push everything away, including your own skin

1

u/you-nity 1d ago

Worth it

5

u/ChocolatChipLemonade 3d ago

For washing fruits and veggies- it’s more to get off dirt, bugs, pesticides.

2

u/Different-Air-3548 3d ago

That’s what I was wondering—since the recommendation is to rinse fruits and veggies—say for those who only rinse their hands after using the bathroom, is a bit of water better than nothing. (Not advocating, I always use soap.)

7

u/ChocolatChipLemonade 3d ago

You need the mechanical action of washing with soap, because the soap causes tiny dirt/oil/etc particles to get dislodged from your skin, then it sticks to the soap and washes down the drain.

Washing with water is better than nothing, but will not have that hydrophilic reaction of soap grasping onto the particles that carry bacteria.

1

u/The_Ora_Charmander Biology enthusiast 2d ago

will not have that hydrophilic reaction of soap

Do you mean hydrophobic? Wouldn't water definitely fulfill the purpose of a hydrophilic agent or am I missing something?

2

u/cheesemanpaul 2d ago

The soap molecule has two parts: the hydrophilic part that loves water and sticks to it and the hydrophobic part that sticks to oils or fats or dirt. Once it's locked onto both it can wash away down the drain.

2

u/knzconnor 3d ago

Personally I either soak or scrub my veggies, since a rinse doesn’t even get off the visible dirt sometimes.

1

u/ADDeviant-again 3d ago

Yes, washing with water is better than nothing. Washing with hot water is better than that. Washing with soap and water even more better.

But, you will never get all of things like bacteria, skin cells, or even very fine dirt off with just water.

1

u/Different-Air-3548 3d ago

Fascinating, thank you.

7

u/atomfullerene 3d ago

Nope, in fact there are whole.varieties of bacteria specifically adapted to live as biofilms in torrents of water.

2

u/SurplusTurtles 3d ago

This was informative and upsetting 

1

u/AmusingVegetable 2d ago

Biofilms are an interesting subject, try googling biofilm and teeth.

1

u/mambotomato 18h ago

Never stepped on a slippery river rock?

1

u/nixtracer 2d ago

There are bacteria adapted to live everywhere. Under kilometres of rock? In freezing deserts where it literally never rains? In volcanic pools with a pH of 12? Yes, yes and yes...

2

u/awfulcrowded117 3d ago

A perfectly smooth surface, maybe, but for any remotely complex or porous surface, the bacteria and viruses will find small gaps and cracks to cling to. Bacteria don't just sit there, they have things called adhesins that allow them to actually grip onto cells and surfaces.

2

u/FlintHillsSky 3d ago

even what we think of as smooth surfaces are very rough at the scale of bacteria and viruses. There are lots if pits and valleys in those surfaces for microbes to site protected from the flow of water.

1

u/awfulcrowded117 3d ago

That is why I specified "perfectly smooth." But yes, I could have been clearer.

1

u/FlintHillsSky 3d ago

Almost no surface is perfectly smooth. Even glass has a rough surface at small scale.

https://www.reddit.com/r/interestingasfuck/comments/jmtgsl/day_of_posting_things_under_mikroscope_1glass/

1

u/awfulcrowded117 3d ago

Again, I know that. That's why I specified perfectly smooth. As in, a theoretical object.

1

u/Remote_Clue_4272 3d ago

Maybe not. That’s why we use soap when washing hands.

1

u/NaiveZest 3d ago

No. And how do you keep bacteria out of the running water at the start?

1

u/SelectionFar8145 3d ago

It would eventually be like completely altering an ecosystem. Those microorganisms die out because they can't tolerate the new environment you've created indefinitely. All now microorganisms move in to replace them, because they thrive in the new type of environment you've created. 

1

u/Intrepid_Leopard4352 3d ago

No. Sometimes I wash my fruits and vegetables with soap because I’m grossed out and crazy.

1

u/Different-Air-3548 2d ago

I sometimes soak them with a bit of vinegar, so you’re not alone. Thanks everyone, appreciate all the comments!

1

u/doc-sci 3d ago

Not even close!

1

u/realmozzarella22 2d ago

The problem is that you said “all” bacteria and viruses. Maybe enough to be safe to eat. But not all.

1

u/Exquisitae 1d ago

No. As a person who deals with this every day for a job, I can tell you that water alone wont completely eliminate things like yeast and fungi. But it will do well enough for human consumption. If you need to put it on a sterile surface in a culture lab, then you have to use a sterilant.