Coronavirus and starsan

[Robert65]

Let's revisit the "no rinse" bleach formula promoted by Charlie Talley (inventor of Star San) and others.


The no rinse formula gets away with just 80 ppm sodium hypochlorite by acidification to a pH of 5.0. At this pH, virtually all of the free chlorine is in the form of hypochlorous acid, which is the form which actually does the job.

Normally, one needs a concentration of at least 200 ppm sodium hypochlorite in order to have an effective sanitizer, assuming higher pH in plain tap water, to ensure a sufficient concentration of hypochlorous acid.

It is below pH 5.0 that chlorine gas begins to evolve, so this acidification must be carried out carefully.

Now, regarding the 1/3 cup per gallon recommendation. This is far above 200 ppm sodium hypochlorite. And since acidification to pH 6.5 is not sufficient either to significantly increase the concentration of hypochlorous acid (which is already quite sufficient,) nor to produce chlorine gas, it would seem to me that such acidification is not necessarily dangerous, but rather superfluous. So why chance it?

 

[Bilsch]

Let's revisit the "no rinse" bleach formula promoted by Charlie Talley (inventor of Star San) and others.


The no rinse formula gets away with just 80 ppm sodium hypochlorite by acidification to a pH of 5.0. At this pH, virtually all of the free chlorine is in the form of hypochlorous acid, which is the form which actually does the job.

Normally, one needs a concentration of at least 200 ppm sodium hypochlorite in order to have an effective sanitizer, assuming higher pH in plain tap water, to ensure a sufficient concentration of hypochlorous acid.

It is below pH 5.0 that chlorine gas begins to evolve, so this acidification must be carried out carefully.

Now, regarding the 1/3 cup per gallon recommendation. This is far above 200 ppm sodium hypochlorite. And since acidification to pH 6.5 is not sufficient either to significantly increase the concentration of hypochlorous acid (which is already quite sufficient,) nor to produce chlorine gas, it would seem to me that such acidification is not necessarily dangerous, but rather superfluous. So why chance it?

It’s as easy as 1oz bleach and 1oz vinegar in one gallon of water. These levels are too low to form chlorine gas. The major advantage of this mix is it won’t bleach out surfaces it contacts like the higher concentration bleach only solution. Another big advantage is the smell. I personally hate the smell of hypochlorite and if you start slinging strong bleach solution around your house every day, you will not be happy.

If you are really worried about it and have a pH meter then make the minimum concentration solution: Use 1oz bleach in 5 gallons of water and enough vinegar to get a pH of ~6.5

 

[Robert65]

Of course this is all just hypothetical right now while there is no more bleach to be had than there is toilet paper. [emoji6]

 

[Bilsch]

Of course this is all just hypothetical right now while there is no more bleach to be had than there is toilet paper. [emoji6]

Another great reason to only need 1oz per gallon of water.

Or for our friends in metric countries:
1.7ml of bleach, 1.7ml vinegar in 1 litre of water. That will stretch your hypochlorite a good long way.

 

[Brett_Bellmore]

Related question: What's the life of this virus in, say, a 5-8% alcohol solution with a little bit of sugar and other non-toxic ingredients?

IOW, if I happened to be sick when I bottled, would those bottles potentially be infectious when drank?

Naturally, I'm not going to bottle when I know I'm sick, but there does seem to be a period where you're infectious but largely asymptomatic.

 

[augiedoggy]

Related question: What's the life of this virus in, say, a 5-8% alcohol solution with a little bit of sugar and other non-toxic ingredients?

IOW, if I happened to be sick when I bottled, would those bottles potentially be infectious when drank?

Naturally, I'm not going to bottle when I know I'm sick, but there does seem to be a period where you're infectious but largely asymptomatic.

If you happen to have it while bottling your body would have the antibodies to not get it again from what Ive been told.. Of course this doesnt address giving it to others who may drink your beer but after 2 weeks of carbonating in the bottle it should be dead with no host as far as I understand but I could be wrong here.

 

[BartJY]

I contacted the company that makes Star San and asked them if their product kills the Covid-19 virus. The answer was NO. So there you have it.

 

[Northern_Brewer]

That's a regulatory thing - the rules are very specific on what they can and can't claim to kill. If you have rat poison and it's not been tested on mice, then you can't say it kills mice.

(and there's a biological technicality in that arguably nothing "kills" viruses as they aren't alive in the first place)

 

[Terpene]

Disclaimer upfront: Use only EPA approved disinfectants against SARS CoV-2.

That said, it's an interesting academic question as to whether Starsan would be an effective disinfectant against viruses like like influenza and SARS CoV-2. We don't know the definitive answer, but knowledge of some of the basic science could help lead us toward a reasonable hypothesis.

Many of the approved SARS CoV-2 disinfectants use ionic surfactants, like benzalkonium chloride. Starsan is also based on an ionic surfactant called dodecylbenzenesulfonic acid, belonging to a class called alkylbenzene sulfonates (https://en.m.wikipedia.org/wiki/Alkylbenzene_sulfonates). These surfactants are believed to exert biocidal activity through similar mechanisms -- compromising bacterial/vrial structure by interfering with the lipid bilayer.

We know a fair bit about the structure of SARS CoV-2 and also about its mechanism of infection. We know it's an enveloped virus with its viral envelope composed mostly of a lipid bilayer stolen from the host cell as the virion buds off from host (epithelial) cells.

This lipid bilayer is not fundamentally different from those that make up the cell wall of bacterial cells. (Yes, there are differences, but the fundamental structural phospholipid bilayer is conserved.) In fact, we know some species of bacteria have complex defense mechanisms that go well beyond the scant protection provided by a lipid bilayer (e.g., biofilms).

So it's reasonable, in my view, to suspect that coronaviruses like SARS CoV-2 would be equally or more susceptible to ionic surfactants than many bacteria, not less. So if starsan effectively kills the bacteria, it's reasonable to suspect it can effectively destroy SARS CoV-2 particles too.

So yeah, I think properly mixed starsan would probably be effective on hard surfaces. But I'd only use it in a pinch or as an adjunct to approved disinfectants.

You could cover way more surface area with Starsan than, say, Lysol, just based on cost and availability considerations. And of course, as mentioned, bleach solutions are known to be highly effective disinfectants. Being diligent in cleaning and wiping down surfaces is probably more important than disinfectant choice, anyway.

Stay safe, friends. Take care of each other. We're all in this together.

 

[passedpawn]

Disclaimer upfront: Use only EPA approved disinfectants against SARS CoV-2.

That said, it's an interesting academic question as to whether Starsan would be an effective disinfectant against viruses like like influenza and SARS CoV-2. We don't know the definitive answer, but knowledge of some of the basic science could help lead us toward a reasonable hypothesis.

Many of the approved SARS CoV-2 disinfectants use ionic surfactants, like benzalkonium chloride. Starsan is also based on an ionic surfactant called dodecylbenzenesulfonic acid, belonging to a class called alkylbenzene sulfonates (https://en.m.wikipedia.org/wiki/Alkylbenzene_sulfonates). These surfactants are believed to exert biocidal activity through similar mechanisms -- compromising bacterial/vrial structure by interfering with the lipid bilayer.

We know a fair bit about the structure of SARS CoV-2 and also about its mechanism of infection. We know it's an enveloped virus with its viral envelope composed mostly of a lipid bilayer stolen from the host cell as the virion buds off from host (epithelial) cells.

This lipid bilayer is not fundamentally different from those that make up the cell wall of bacterial cells. (Yes, there are differences, but the fundamental structural phospholipid bilayer is conserved.) In fact, we know some species of bacteria have complex defense mechanisms that go well beyond the scant protection provided by a lipid bilayer (e.g., biofilms).

So it's reasonable, in my view, to suspect that coronaviruses like SARS CoV-2 would be equally or more susceptible to ionic surfactants than many bacteria, not less. So if starsan effectively kills the bacteria, it's reasonable to suspect it can effectively destroy SARS CoV-2 particles too.

So yeah, I think properly mixed starsan would probably be effective on hard surfaces. But I'd only use it in a pinch or as an adjunct to approved disinfectants.

You could cover way more surface area with Starsan than, say, Lysol, just based on cost and availability considerations. And of course, as mentioned, bleach solutions are known to be highly effective disinfectants. Being diligent in cleaning and wiping down surfaces is probably more important than disinfectant choice, anyway.

Stay safe, friends. Take care of each other. We're all in this together.

I don't think acid sanitizers are very effective against the fatty lipid envelope of virii. (also, as someone above might have already said, virii are not "alive" as bacteria are - different things altogether). E.g., vinegar would not be effective. Vinegar is about the same as stomach (gastric) acid, 2-3 pH. I think I read that the virus has been detected in fecal samples of infected butts, so it survived the GI tract. Starsan, when diluted per instructions, is somewhere below 3 pH, similar to the other acids.

I suppose if the pH was low enough, it might do something, but who knows. I know this is an academic exercise, because anyone interested in avoiding the virus would just use bleach.

 

[HB_ATL73]

to my untrained foramen magnum

to your hole in your head? Haha! you got me laughing that was a great post

 

[Jayjay1976]

to your hole in your head? Haha! you got me laughing that was a great post

I minored in anthropology for a couple of semesters. This was the first time I've ever busted out any of that knowledge, thanks for picking up on it!

 

[Gnomebrewer]

I don't think acid sanitizers are very effective against the fatty lipid envelope of virii. (also, as someone above might have already said, virii are not "alive" as bacteria are - different things altogether). E.g., vinegar would not be effective. Vinegar is about the same as stomach (gastric) acid, 2-3 pH. I think I read that the virus has been detected in fecal samples of infected butts, so it survived the GI tract. Starsan, when diluted per instructions, is somewhere below 3 pH, similar to the other acids.

I suppose if the pH was low enough, it might do something, but who knows. I know this is an academic exercise, because anyone interested in avoiding the virus would just use bleach.

It's not the acidity alone that works to kill microbes, it's partly the action of the surficant breaking apart the cell wall. Check out this video
From that perspective, it's as Terpene said - starsan probably works on viruses, given similarities to bacteria in cell wall structures, but might not - there are differneces (paraphrasing). But yeah, just use bleach if you can.

 

[Northern_Brewer]

I don't think acid sanitizers are very effective against the fatty lipid envelope of virii. (also, as someone above might have already said, virii are not "alive" as bacteria are - different things altogether). E.g., vinegar would not be effective. Vinegar is about the same as stomach (gastric) acid, 2-3 pH. I think I read that the virus has been detected in fecal samples of infected butts, so it survived the GI tract. Starsan, when diluted per instructions, is somewhere below 3 pH, similar to the other acids.

I suppose if the pH was low enough, it might do something, but who knows. I know this is an academic exercise, because anyone interested in avoiding the virus would just use bleach.

That's the point, it's not academic and when people actually do experiments rather than just a thought experiment they find that bleach doesn't work as well as soap, and vinegar, even diluted in hot water, works fairly well against coronaviruses in general - see the paper I linked earlier. If it is genuinely passing through the gut (as opposed to being picked up in bathrooms or elsewhere in the sewage system) then it is probably only doing so when encapsulated in snot, protecting it from the acid. They're not terribly robust things in general, not like anthrax/botulism spores.

 

[passedpawn]

That's the point, it's not academic and when people actually do experiments rather than just a thought experiment they find that bleach doesn't work as well as soap, and vinegar, even diluted in hot water, works fairly well against coronaviruses in general - see the paper I linked earlier. If it is genuinely passing through the gut (as opposed to being picked up in bathrooms or elsewhere in the sewage system) then it is probably only doing so when encapsulated in snot, protecting it from the acid. They're not terribly robust things in general, not like anthrax/botulism spores.

Ah, I see. 10% vinegar is as good as 1% bleach. Good to know, thanks.

 

[Northern_Brewer]

Ah, I see. 10% vinegar is as good as 1% bleach. Good to know, thanks.

In the experimental conditions tested in that paper, against those particular viruses, then yes. Obviously bleach has a wider spectrum of action, but right now we're particularly interested in what works against coronaviruses, and as far as that goes, bleach in hot water seems to work quite well. Worth emphasising that just normal cleaning gets rid of 99% of the nasties, any chemical treatment is about wiping out 99+% of what's left.

Just on the GI thing, I knew I'd seen something yesterday but couldn't find it. Woelfel et al : "Pharyngeal virus shedding was very high during the first week of symptoms (peak at 7.11 × 108 RNA copies per throat swab, day 4). Infectious virus was readily isolated from throat- and lung-derived samples, but not from stool samples, in spite of high virus RNA concentration. Blood and urine never yielded virus."

Thing is, it's very easy to test for viral genetic material and so people find it everywhere, but that's very different to finding live virus which is much slower/expensive to test for. This paper is consistent with the idea that passing through the stomach acid smashes up the virus, so you can detect fragments by genetic tests but there's nothing viable left that could cause infection. It similar to how people are finding genetic material 3-4 weeks after infection, but the actual period where transmission is possible is much shorter, maybe 5 days in mild cases, 8 days in more severe cases.

 

[Terpene]

I don't think acid sanitizers are very effective against the fatty lipid envelope of virii. (also, as someone above might have already said, virii are not "alive" as bacteria are - different things altogether). E.g., vinegar would not be effective. Vinegar is about the same as stomach (gastric) acid, 2-3 pH. I think I read that the virus has been detected in fecal samples of infected butts, so it survived the GI tract. Starsan, when diluted per instructions, is somewhere below 3 pH, similar to the other acids.

I suppose if the pH was low enough, it might do something, but who knows. I know this is an academic exercise, because anyone interested in avoiding the virus would just use bleach.

As a fellow chess player, I appreciate your name, passedpawn!

As others have mentioned and I mentioned in my post, starsan works not by pH alone. The low pH provides the environment for the *ionic surfactant* to do the job. So understanding that mechanism is the key. The Sui Generis guys explain it perfectly in the video Gnomebrewer was nice enough to link above.

You are absolutely correct in pointing out viruses are not alive. But as I mentioned, viruses share one important feature (among others) with living cells: the lipid bilayer. Destroy the integrity of the lipid bilayer and you destroy the virus particle. Same mechanism as in the Sui Generis video vs bacteria and yeast.

Regarding bleach, yes I agree people should use it. It works. But bleach works through an oxidative mechanism. And not everyone wants to go around spraying an oxidizer everywhere. Its reactivity is its advantage and its disadvantage.

 

[Terpene]

Also, if anyone is looking for another disinfectant that you may already have in your brew kit, it's lactic acid.

There are already lactic acid based commercial products on the EPA approved list for SARS-CoV-2 disinfectants.

Note, concentration vs contact time:
1.77% 5 minutes
0.19% 10 minutes

Cites and related links:
https://www.epa.gov/pesticide-registration/list-n-disinfectants-use-against-sars-cov-2

https://www3.epa.gov/pesticides/chem_search/ppls/004822-00606-20150226.pdf

https://www3.epa.gov/pesticides/chem_search/ppls/004822-00606-20150226.pdf

https://www.corbion.com/media/434618/corbion_a_safe_antimicrobial_for_hpc_applications_eng.pdf