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How Soap Works: The Science Behind Handwashing

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Re: How Soap Works: The Science Behind Handwashing

#41

Post by itishappy »

downWidOutaFite wrote: post #34
Kranar wrote: post #14

Earlier quoted context omitted.

I mean yes, technically soap will destroy viruses that are already in your body absolutely. It will also destroy many other cells and proteins in your body as well since soap is an indiscriminate killer. The end result is that both viruses and normal tissue will end up dying which will damage you or possibly kill you.

This doesn't sound right. Soap is considered nontoxic. We all ingest soap residue from dishes and other hygiene and I've never heard anyone concerned about it.

That's not quite right either. Soaps and detergents are not intended for internal use. The residue won't kill you (because it's incredibly diluted) but ingesting the raw product would cause problems such as nausea and vomiting.

That's why there's an entirely separate class of soap products formulated specifically for those among us who own and operate a vagina.

Re: How Soap Works: The Science Behind Handwashing

#42

Post by mrguyorama »

downWidOutaFite wrote: post #34
Kranar wrote: post #14

Earlier quoted context omitted.

I mean yes, technically soap will destroy viruses that are already in your body absolutely. It will also destroy many other cells and proteins in your body as well since soap is an indiscriminate killer. The end result is that both viruses and normal tissue will end up dying which will damage you or possibly kill you.

This doesn't sound right. Soap is considered nontoxic. We all ingest soap residue from dishes and other hygiene and I've never heard anyone concerned about it.

>I've never heard anyone concerned about it.

I think people should abandon this heuristic.

Re: How Soap Works: The Science Behind Handwashing

#43

Post by amluto »

g-b-r wrote: post #12
mholt wrote: post #5

I'm a huge advocate for washing with soap and water, but this gave me pause: > washing your hands with soap and water is one of the most effective ways people can keep from getting sick, and from passing the [COVID-19] virus to others So not to doubt handwashing, but I thought we overwhelmingly determined that COVID-19 doesn't thrive on surfaces (very long) and its primary transmission vector is through the air, from…

Is it really something that needs to be advocated? Is there really someone for which washing hands is less obvious then breathing?

Then advocate for it with a valid reason?

There seem to be plenty of diseases that are commonly spread by inadequately washed hands. COVID does not appear to be one of them.

Re: How Soap Works: The Science Behind Handwashing

#44

Post by NoImmatureAdHom »

Isthatablackgsd wrote: post #32
ProjectArcturis wrote: post #4

I understand soap molecules having polar and nonpolar ends, so that it can help nonpolar things dissolve in water. What I've never understood is, why doesn't soap clean off pine sap?

Pine sap are not water soluble, even with soap. Pine sap is resin based, resins need a different solvent that can dissolve it such as alcohol or mineral spirits. It the same for wax (THC/CBD) resins, they need alcohol to clean it off. It the same for blood stains on clothing. They are not generally water soluble, you could get them out if you put it under cold water if the stain is still fresh. Hydrogen Peroxide can…

I'm pretty sure with H2O2 (hydrogen peroxide) it's actually destroying the chromophores in blood (among other things), not dissolving stuff.

Put differently, it breaks up the stain molecules into smaller molecules and causes other reactions that change them, it doesn't just dissolve them. You can dissolve resinous stuff with various solvents, you're right about that. Stays mostly the same, just goes into solution.

Re: How Soap Works: The Science Behind Handwashing

#45

Post by nextos »

downWidOutaFite wrote: post #34
Kranar wrote: post #14

Earlier quoted context omitted.

I mean yes, technically soap will destroy viruses that are already in your body absolutely. It will also destroy many other cells and proteins in your body as well since soap is an indiscriminate killer. The end result is that both viruses and normal tissue will end up dying which will damage you or possibly kill you.

This doesn't sound right. Soap is considered nontoxic. We all ingest soap residue from dishes and other hygiene and I've never heard anyone concerned about it.

Actually residue from fancy dish soaps is known to be a gut irritant, see https://www.sciencedirect.com/science/article/pii/S009167492...

For this reason, I stick to either first-generation soap (made by saponification) or simple surfactants.

In general, as a precautionary principle, it is always good to stick to simple products that have been around for a long time.

Re: How Soap Works: The Science Behind Handwashing

#46

Post by amluto »

downWidOutaFite wrote: post #34
Kranar wrote: post #14

Earlier quoted context omitted.

I mean yes, technically soap will destroy viruses that are already in your body absolutely. It will also destroy many other cells and proteins in your body as well since soap is an indiscriminate killer. The end result is that both viruses and normal tissue will end up dying which will damage you or possibly kill you.

This doesn't sound right. Soap is considered nontoxic. We all ingest soap residue from dishes and other hygiene and I've never heard anyone concerned about it.

People are, in fact, concerned about it, although some studies suggest that the types of surfactants used in rinse aid are worse than the kinds used to wash dishes:

https://www.sciencedirect.com/science/article/pii/S009167492...

And overuse of soap is definitely irritating to skin — this is not a particularly subtle effect.

Re: How Soap Works: The Science Behind Handwashing

#47

Post by IKantRead »

jawns wrote: post #10

This is probably the stupidest question many of you will encounter today, but: If soap has an extraordinary ability to destroy viruses on our skin ... can eating soap give us some of those benefits for viruses that are already in our bodies? I'm not seriously envisioning chowing down on bar soap or using liquid hand soap as a salad dressing. But are there ways to use the _properties_ of soap that make it good for kil…

> can eating soap give us some of those benefits for viruses that are already in our bodies?

I think the thing people are missing in a lot of these comments is that viruses are typically traveling from the skin to a mucus membrane in your body (which can be in the stomach but also in your lungs and nose), then infecting your cells. Eating soap might impact pathogens in your still in your stomach, but it's not going to dissolve in your blood and circulate through your body at high enough concentrations to impact viruses...

...and if it was high enough concentration: imagine snorting, inhaling or injecting dish soap.

Re: How Soap Works: The Science Behind Handwashing

#48

Post by amluto »

nextos wrote: post #45
downWidOutaFite wrote: post #34

Earlier quoted context omitted.

This doesn't sound right. Soap is considered nontoxic. We all ingest soap residue from dishes and other hygiene and I've never heard anyone concerned about it.

Actually residue from fancy dish soaps is known to be a gut irritant, see https://www.sciencedirect.com/science/article/pii/S009167492... For this reason, I stick to either first-generation soap (made by saponification) or simple surfactants. In general, as a precautionary principle, it is always good to stick to simple products that have been around for a long time.

I generally try to avoid traditional soaps (saponified oils). They’re only soapy at in basic solution, and skin is naturally a bit acidic. Even for washing dishes, there are mildly unfortunate interactions — try mixing Dr. Bronner’s soap with any acidic food. You get a gooey mess that isn’t soapy. On the other hand, I suppose that traditional soap residue that anyone with normal stomach acid manages to eat will turn back into free fatty acids.

(Skin is, in general, rather more sensitive to bases than acids. Even a fairly mild base will make skin feel unpleasant and a bit slimy, whereas holding an orange slice (quite acidic) is not particularly irritating to intact skin.)

Re: How Soap Works: The Science Behind Handwashing

#50

Post by nextos »

amluto wrote: post #48
nextos wrote: post #45

Earlier quoted context omitted.

Actually residue from fancy dish soaps is known to be a gut irritant, see https://www.sciencedirect.com/science/article/pii/S009167492... For this reason, I stick to either first-generation soap (made by saponification) or simple surfactants. In general, as a precautionary principle, it is always good to stick to simple products that have been around for a long time.

I generally try to avoid traditional soaps (saponified oils). They’re only soapy at in basic solution, and skin is naturally a bit acidic. Even for washing dishes, there are mildly unfortunate interactions — try mixing Dr. Bronner’s soap with any acidic food. You get a gooey mess that isn’t soapy. On the other hand, I suppose that traditional soap residue that anyone with normal stomach acid manages to eat will turn…

That is true. Traditional soaps are quite messy. One trick with Dr Bronner's is to rinse with vinegar afterwards to balance pH.
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