Kevin Outterson writes of “Hand Sanitizers as Agent Orange”:
Over at CommonHealth, Aayesha rounds up the literature on the limits of hand sanitizers, but fails to mention the collateral damage to the skin microbiome. Alcohol-based hand sanitizers kill many bacteria, viruses and fungi, but they don’t selectively target pathogens. They kill a wide swath of the microbial life on your hands, including little-understood non-pathogenic species. For an ecological analogy, think of using Agent Orange to kill a couple weeds.
A good introduction to the skin microbiome is a recent article in Nature Reviews Microbiology by Elizabeth A. Grice and Julia A. Segre (9, 244-253 (Apr. 2011)). From the abstract:
“The skin is the human body’s largest organ, colonized by a diverse milieu of microorganisms, most of which are harmless or even beneficial to their host. Colonization is driven by the ecology of the skin surface, which is highly variable depending on topographical location, endogenous host factors and exogenous environmental factors. The cutaneous innate and adaptive immune responses can modulate the skin microbiota, but the microbiota also functions in educating the immune system.”
As I’ve said before, our relationship with microbes should also be evaluated as an ecological issue. Completely germ-free environments are not necessarily the goal.
Do you have sympathy for kitty?
Wa – T – F? Kitty who? Kitty litter? Sheesh.
A “germ” is by definition, harmful, so yes, we do want germ free environments. Trying to promote healthy microbes is very popular (probiotics). Minimizing collateral damage to neutral microbes is a good idea, but that’s generally a low priority.
“germ” is the colloquial term for microorganism, and in this sense most do not even consider that beneficial ones even exist. Generalized hypochondria has created a sense that killing all “germs” is okay not considering that there may just be more beneficial and “neutral” microbes than there are negative ones.
+ 1 trillion
A germ is harmful by definition only if you define “germ” to mean harmful microorganisms. But that isn’t what most dictionaries say “germ” means.
Clay: one has to be careful, though. Think of the early vaccination results: for sure, it would be better to be rid of both, but areas without cowpox are more susceptible to smallpox. So being a germ-free zone is a little more complicated, at least in terms of ‘how we get there’ than simply bashing whichever germs are easiest to eradicate.
Kill them all and let God sort them out…
But seriously… getting out of the habit of brushing your nose or eyes with your fingers is probably more helpful in avoiding disease than using hand sanitizers.
Yep.
I am curious about the response from the “OMG, get rid of the germs” crowd when they learn that around 1% of their body weight is bacteria and that bacteria in and on a human out-number the human cells in a human. I guess a lot of them refuse to believe it and stop thinking about it but I don’t really know.
Why don’t we have bacteria-based hand desanitizers?
That’s a great idea! Probiotics for the hands! Whether or not it would really be beneficial, it would be easy to write advertising copy that would make it seem like the best thing in the world. For your kids. You want the best for your kids, right?
I’d think that has the possibility of causing other problems. To remove the bad stuff you would need a significant number of probiotics, but what’s good for your skin is not necessarily good for the digestive system. And significant amounts of anything on your hands often end up in your digestive system.
Use the same bacteria that are in probiotic dietary supplements. Problem solved! In the world of unregulated health quackery, it doesn’t matter if it works or not, as long as the claims are carefully worded to avoid making a drug claim. It’s perfectly okay to say “supports a healthy skin microbial ecology” or something like that. Just don’t say something like “cures athlete’s foot”.
Going from “hand sanitizer” to “Completely germ-free environments” seems like kind of a big leap.
In what way? Hand sanitizer destroys nearly all bacteria on your skin, without any bias for the bad bacteria.
It kills all the bacteria on your hands. Not even all the bacteria on your skin, much less all the bacteria in the environment.
In other words, there is an “optimal level” of germs . . .
There is well-known theory regarding the causal relationship between over-sanitized environments and allergy incidence. My allergist told me about it – also that the evidence wasn’t there yet, but it is a well known and respectable hypothesis.
What explains the allergy epidemic among kids in the US ?
Their parents not having died in childhood.
I don’t think so.
It may be a respecatble hypothesis, but there is scarce evidence from solid large scale studies to support the “hygiene hypothesis”. It is a bit SWPL.
http://www.ncbi.nlm.nih.gov/pubmed/15121716
Sorry – just read the abstract and I don’t understand how you come to that conclusion.
The incidence of allergies is lower in developing (read dirty) countries. Whether this is only an under-reporting issue I can’t say.
When you are hungry, you are less likely to notice (or complain about?) a runny nose. Or that fly on your eye…..
This kind of posts should go under the heading of “Life is Too Complicated to Get Right” or “We’re Experts, Trust Us Until We Change Our Mind (Again)”.
You’re just a pessimist.
So, what does shower soap do? Hand diswashing detergent? If we indeed have a pre-sanitizer biosystem, it would be pretty tweaked for our current lifestyles.
Yeah, how about hot water? How is sanitizer different from running your hands under hot water for 30 seconds as recommended?
Any water hot enough to kill all germs in 30 seconds ought to make you scream in pain.
Rahul, maybe the recommendation is 1 minute, I don’t know. If it doesn’t work, why do we care if people do it after going to the bathroom?
So you do your business in the airport restroom, pull up your pants and buckle your belt, push open the stall door and then, finally, get your hands in the sink. Then you push open the door and leave. If fecal bacteria were visible in blaze orange under some kind of special light source, your hands and crotch area would be a beacon visible from one end of the concourse to the other.
think of using Agent Orange to kill a couple weeds.
2,4,D & 2,4,5,T, the primary components of agent orange, are used in most lawn weed killers…
Not 2,4,5-t it’s practically been banned
Like John said, soap does the same thing. It kills all the microbes on your hand. Guess what, that’s a good thing. Anyone worried about polio coming back? Didn’t think so.
Yeah, but you don’t always have access to running water and hand sanitizer comes in handy then.
Do you mean antibacterial soap (which actually is not left on the hands long enough to kill many bacteria)? Soap is just a surfactant, right? It’s the water that kills them/washes them off?
The secret is that all soap is antibacterial. It tears apart their little lipids. Now, “antibacterial soap” is probably “extra” in some way.
Bingo! Soap is just as effective as anti-microbials.
http://www.ewg.org/node/26859
antimicrobial soap does not work any better than plain soap and water at preventing the spread of infections or reducing bacteria on the skin, according to our survey of the scientific literature and published agency positions
Thanks!
Tyler, you surprise me sometimes. I would take a libertarian perspective on this issue. Do you now expect us to regulate (more) hand sanitizers?
Tyler is flexible..
I certainly didn’t get that from the post.
I actually worked on germ control [bacteria] in my last job.
I’m not sure if the alcohol wipes are for bacteria or viruses.
In regard to bacteria
I think it is safe to say that of the thousands of bacteria that are found on the human body, we know that a small number cause a lot of the bacterial disease – eg S Aureus, K pneumonia, Acinetobacter baumanii, P fluorescens (a particular problem in teh lungs of CF patients).
Rather then worrying about all the small stuff, lets worry about S aureus (aka MRSA) which we know is killing alot of people, and causing a lot of non fatal illness.
One clear example of how removing bacteria is bad: Vancomycin is a powerful antibiotic often given to treat serious infections. Vanco tends to wipe out the normal flora in the gut (you take vanco as a pill or IV). When this happens, a bug known as Clostridium difficle takes over your gut, and can cause serious life theatening gut ulcers.
I don’t know if we have a similar example from hand wipes
No. We’ll just chase chimeras like global warming and how we’re all at risk from AIDS and vaccines to put selection pressure on viruses that are non-fatal to 90+% of the population.
In laboratory work you need to kill everything.
For $30 I just had a woman tell me “rub the head of your penis.” But wait! She was a nurse describing how to prep for urinalysis with an alcohol pad and that was the co-pay.
Everywhere except government and healthcare there would be a sticker on the cup so some poor woman doesn’t have to tell a dude to rub the head of his penis.
Why are hand sanitizers singled out for having unintended consequences here? The bar soap your grandfather used is plenty antibiotic.Why shouldn’t we be thinking twice every time we reach for the mouthwash or the toothpaste?
Not sure, but I’m guessing the good bacteria are well established. Soap is pretty mild and mainly sloughs off poorly attached bacteria that would presumably be the new guys. If you are healthy you don’t want new guys and don’t want to kill the old guys occupying the niche.
What struck me visiting the U.S. was the number of people wearing rubber gloves (especially those handling money and all the people manning the various freedom gates which help keep America safe from its fears), and the omnipresence of ‘sanitizer’ stations.
Since I missed the last five years of how this developed in daily life on the Eastern Seaboard, it was easy to realize just how essentially superstitious Americans have become, surrounded in a bubble of media created information.
And how isolated many Americans prefer to be, either preferring some version of purity of essence, or simply deciding the world is too dangerous to live in without constantly performing acts of purification.
For those interested in a more than 50 year old look at this not exactly unexamined American trait, this link is likely interesting –
‘Professor Linton [3] first brought the ritual of the Nacirema to the attention of anthropologists twenty years ago (1936: 326), but the culture of this people is still very poorly understood. They are a North American group living in the territory between the Canadian Cree, the Yaqui and Tarahumare of Mexico, and the Carib and Arawak of the Antilles. Little is known of their origin, although tradition states that they came from the east….
Nacirema culture is characterized by a highly developed market economy which has evolved in a rich natural habitat. While much of the people’s time is devoted to economic pursuits, a large part of the fruits of these labors and a considerable portion of the day are spent in ritual activity. The focus of this activity is the human body, the appearance and health of which loom as a dominant concern in the ethos of the people. While such a concern is certainly not unusual, its ceremonial aspects and associated philosophy are unique.
The fundamental belief underlying the whole system appears to be that the human body is ugly and that its natural tendency is to debility and disease. Incarcerated in such a body, man’s only hope is to avert these characteristics through the use of ritual and ceremony. Every household has one or more shrines devoted to this purpose. The more powerful individuals in the society have several shrines in their houses and, in fact, the opulence of a house is often referred to in terms of the number of such ritual centers it possesses. Most houses are of wattle and daub construction, but the shrine rooms of the more wealthy are walled with stone. Poorer families imitate the rich by applying pottery plaques to their shrine walls.’
https://www.msu.edu/~jdowell/miner.html?pagewanted=al
I don’t know. After 10 years of almost never getting sick I’m now sick 2+ weeks a month on average and the only change is having a kid in daycare. A fully vaccinated kid by the way. If the exogenous immune system is that fragile gloves seem fine to me.
Forget ageing?
I did have the same experience. I was 28, it seems unlikely my immune system degraded that fast due to age.
Please don’t tell me you plan to wear rubber gloves when your child is around.
Or worse, make your child wear gloves all the time at daycare.
Once again I have no idea what you’re talking about. The only people I ever see wearing rubber gloves are involved in (a) food preparation or (b) the medical field.
Bank tellers, food store cashiers (in several states, and several chains), security personnel manning the various ‘freedom gates’ that are so common in both DC government buildings and NYC museums, the UN, and places like the ferry terminal to Liberty/Ellis island, the people manning tool boothes, even one person selling tickets at a movie theater – these are ones that stick in memory. Maybe a better term is rubber or plastic hand protection, as compared to surgical equipment. And public hand sanitzing stations, both in private and public institutions, was also something new to me.
Obviously, people serving food with is not really a surprise in American terms (though generally, such hand protection is a lot less common in Germany). That police or fire department personnel often seemed to be wearing such was more than I remember, but also at least understandable, particularly in NYC.
Possibly, since it likely happened over a span of years in which I was not living in the U.S., or because you live somewhere other than Virginia (from Northern VA to Richmond to VA Beach to the Eastern Shore), Baltimore, or NYC, you haven’t noticed. It really struck me, though.
Bacteria are resident in most places of the human body, some places much more than others (armpits, groin, face, mouth, are densely populated, the back relatively bacteria-free).
Hands are a special case for a number of reasons, but mainly because of what people tend to do with them (such as, put them in their mouth, eyes, ears, and in other peoples teeth, contaminated public objects, and so on): Linked article explains a bit in non-technical terms and might be useful if you are a Saturday Night hero type:
global-training-report.com/jab.htm
So, use hand sanitizer, wash hands, and then scratch your…armpits?
Also important: there is an optimal rate of minor sickness, and it is probably not “never.” Occcassional minor illnesses keep the immune system in good order.
No Andrew, I didn’t say that.
Recall also, please, that most of the time your hands have not just been sanitized within the previous 20 minutes. Even if you use hand sanitizer, your microbial flora will be right back real fast. If you are like most people, your fingers are going to touch things (door handles, money, for examples) that harbor transient micro-organisms, and you are then sooner or later going to touch your own mouth, ears, eyes.
Skin over knuckles is another issue: http://www.global-training-report.com/jab.htm
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