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RE: A Show of Hands....?

This is a very interesting article, it’s nice to see the topic of antimicrobials and resistances discussed more often. I 100% agree with a lot of the points you made, especially about the single use plastic waste in the purse pack hand sanitizers. There were a few things I wanted to point out however.

The article you linked to is excellent, although I noticed that it’s focusing primarily on the food industry and one of the first comments they make is about how a lot of evidence gathered on the effectiveness of alcohol as a disinfectant is tailored to the health industry, and so they wanted better evidence on their industry. For the food industry they’re right - hand washing is more effective than alcohol rubs. I’m guessing partly because of residues left on the hands from the food, but of course you don’t want to be then touching food with the residue from alcohol rubs.

Another thing to consider is what is actually used in hospitals. I realise this may vary a lot, so I can only speak for Australia and even then it could vary between hospitals. They generally use a 90% alcohol rub, which is capable of killing almost all bacteria and viruses other than rabies and possibly TB. 70% alcohol however can’t kill enveloped viruses (if I recall correctly, that includes influenza, HIV and the common cold virus).

Something I disagreed on was the statement about triclosan. I definitely don’t think it’s good, but it isn’t used in hand sanitizers with alcohol in (at least not here) because the whole purpose of triclosan is to be an alternative that’s used in alcohol free hand sanitizers. So while it is definitely not a good compound, as far as I know it is definitely not a primary ingredient in most sanitizers, just the alcohol free kind. Glycerin is used to offset the dryness from the alcohol and can indeed dry out the skin, but only in low humidity environments. This is because it is forming a protective barrier against the skin, so if your hands are already dry then it can end up drawing further moisture from the dermis. It’s kind of like how you can become “dependent” on cheap/bad lip balms. The environmental impact of glycerin is definitely another downside to it though.

Just recently in our labs we did an experiment on just this - the efficacy of hand washing vs. alcohol rubs. Our experiment showed very different results to the article linked, and I have a few theories why. The experiment was done with agar plates how samples of unwashed hands, and then several different combinations (1: hand washed, 2: alcohol rub, 3: handwashed then alcohol rub, 4: handwashed then handwashed, 5: alcohol rub then handwash, 6: alcohol rub then alcohol rub). Our obvious winner was 6, followed by 3, 2, 4 and then 1. One of the main things we had to consider was that hand washing almost always removes the outer layer of oil/protection on your skin, and potentially exposes more bacteria to others (your own skin flora) than to begin with. In the samples for number 1, all but one agar plate showed higher bacteria levels after handwashing than before. If you’re after a very thorough wash I’d be inclined to recommend treatment 3, as it would remove residues, and possibly compounds that the alcohol rub couldn’t kill. We also found that bacteria could be picked up from the hand drying source, and the soap bar (I see that you have mentioned liquid soap though, so this problem would be resolved).

I guess my point here though is that alcohol rubs (80% and above) are an amazing way to quickly disinfect already (mostly) clean hands. So no, not effective in the food industry and no, not effective for doctors and people working in hospitals. But for speed and cleanliness for visitors, I feel they’re very effective. Aside from the environmental downsides of glycerin, alcohol rubs are cheap to produce, extremely effective when around the 90% mark, and don’t promote antimicrobial resistance in any way (they are bactericidal, and kill bacteria which means the bacteria don’t have a chance to develop resistance. Ethyl alcohol uses a process known as “denaturation” wherein the cell membrane is effectively dissolved, along with the insides. Resistance occurs [generally] when the antimicrobial compound is only bacteriostatic, and just disables the bacteria). The problem arises with alcohol-free rubs and the triclosan in them, and thankfully they aren’t used in hospitals, at least over here :)

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Thanks for such a detailed response. 😍

I guess the observation needs to be made that in Australia (where I grew up & lived for many years) the standard of labeling & ingredients in the sanitizers is (hopefully) more tightly controlled than Thailand. I say "hopefully" because of the illusion of control & standards. I export natural products into Oz now & it's one of the easiest countries and requires almost zero manufacturing or ingredient disclosure. Truly.

So much to consider. My biggest response is that while your particular alcohol rub might be effective, it's the repeated use of an environmentally damaging product that denatures & harms the skin which sets that particular individual repeat user up for future bacterial issues, as rough dry skin harbours more bacteria than healthy functioning skin.

In my natural products biz where hand sanitation issues are a daily thing, we (like the food industry) would never allow hand sanitizer due to contamination - same as we dont allow latex gloves due to powder contamination. If I wouldnt contaminate a product with that icky chemical residue, why would I contaminate my immune compromised grandma or a newborn baby by touching them?

I think you win Epic Comment of the Week. 💚