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Scientists Discover That Antimicrobial Wipes and Soaps May Be Making You (and Society) Sick

The views expressed are those of the author and are not necessarily those of Scientific American.

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A few weeks ago as I was walking out of a Harris Teeter grocery store in Raleigh, North Carolina, I saw a man face a moment of crisis. You could see it in the acrobatic contortions of his face. He had pulled a cart out of the area where carts congregate, only to find that its handle was sticky with an unidentifiable substance. He paused and looked at the handle, as if to imagine the nature of the offense. Gum? Meat juice? Chewed marshmallows? So many vulgar possibilities. Forlorn, he reached for an antibiotic wipe conveniently placed by the door. He scrubbed his hands VERY diligently and then pushed the cart back for someone else to rediscover [1].

Scenarios like this one are playing out all over America. There is an epidemic of sticky, dirty and otherwise gross handles on shopping carts. But it isn’t just carts. Disgusting doorknobs have also been found, as have cryptically damp table-tops in restaurants and even, sad as it is, slimy back rests on the weight machines in gyms! Increasingly, the world seems to be rife with contamination. Fortunately, all of the main companies producing hygiene products have offered a solution–sanitary, antibacterial, antimicrobial, antibiotic, wipes, and soaps to kill anything that dares to creep into our wholesome lives. These salves will cure us of the demons that dare to grow near us.

The really intriguing news–a kind of breakthrough–is that the main compounds in antibiotic wipes, creams and soaps, triclosan and/or the chemically similar triclocarban, have also been sprinkled around our lives more generally. A recent study notes that triclosan is now used to "impregnate surfaces and has been added to chopping boards, refrigerators, plastic lunchboxes, mattresses as well as being used in industrial settings, such as food processing plants where walls, floors and exposed machinery have all been treated with triclosan in order to reduce microbial load." You can now go home, wipe your world down and live a happier life, surrounded by an antibiotic force field. Be especially sure to wipe your children down. Children are just about the grimiest thing in the world.

Yet, although I hesitate to digress or cause trouble, the devil on my shoulder, that voice of so-called reason, is urging me to avail myself of more than the vague suspicion that everything around me is contaminated. Maybe, the devil says, we should glance, just for a second, at what scientists like to call–in their nasally ivory-tower voices–"the evidence." I do not mean anything too fancy… Let’s just take a moment to look at a study here and there that might be relevant as we go about coating our lives–from underpants to kitchen pans–in antibiotic wonder.

For example, what if we just considered whether people who wipe down the world around them with antibiotic soap or wipes are less likely to be sick. Of course, they must be. The world is gross and they are, God bless them, clean, but let’s just check.

OK, we shouldn’t have checked. There are some problems. One is the actual evidence, or just as often, lack thereof. Case in point: along with her colleagues, Allison Aiello, a professor at the University of Michigan, recently surveyed all of the experimental or quasi-experimental studies published in English between 1980 and 2006 on the effectiveness of different hand washing strategies [2]. Aiello focused on studies that compared different strategies, for example the use of normal soap versus the use of antibiotic soap, in terms of their effect on the probability of developing gastrointestinal or respiratory illness. Our intuition is that antibiotic soaps and wipes should make everyone healthier. Aiello’s results were something else entirely.

Aiello’s first result was fine enough, but it set the stage for the trouble to come. She found "the use of nonantibacterial soap with hand hygiene education interventions is efficacious for preventing both gastrointestinal and respiratory illnesses." In other words, if you wash your hands with soap (and are educated about washing your hands with soap) you are less likely to get sick. Score one for intuition and grandma’s admonitions. But then things went terribly wrong.

Aiello next considered the antibiotic soaps and wipes now used, in one form or another, by 75% of American households. Odds are that you use them. Go check your labels. Sadly, Aiello and colleagues found that antibiotic soaps and wipes with triclosan were no more likely than good old-fashioned soap to prevent gastrointestinal or respiratory illness. In Aiello’s words, "There was little evidence for an additional impact of new products, such as alcohol-based hand sanitizers or antibacterial soaps compared with nonantibacterial soaps, for reducing either gastrointestinal or respiratory infectious illness symptoms."

For example, in a study Aiello reviewed that was conducted in Pakistan, gastrointestinal illnesses were reduced by half when people washed their hands with soap and by a little less than half when they washed their hands with antibiotic soap [3]. What is worse, perhaps the most comprehensive study of the effectiveness of antibiotic and non-antibiotic soaps in the U.S., led by Elaine Larson at Columbia University (with Aiello as a coauthor), found that while for healthy hand washers there was no difference between the effects of the two, for chronically sick patients (those with asthma and diabetes, for example) antibiotic soaps were actually associated with increases in the frequencies of fevers, runny noses and coughs [4]. In other words, antibiotic soaps appeared to have made those patients sicker. Let me say that again: Most people who use antibiotic soap are no healthier than those who use normal soap. AND those individuals who are chronically sick and use antibiotic soap appear to get SICKER.

Here, then, is the evidence we need, evidence very clearly at odds with our intuition to scrub and scrub. Yet hardly anyone has followed up on Larson’s study and no one has reexamined what happens with chronically sick patients and antibiotic soaps. The truth is that few biologists are studying what antibiotic soaps do to us. Still, the evidence indicates that when confronted with a dirty grocery store cart handle, we should just wash with soap and water like our great grandmothers would have done (if they had had grocery carts). At the very least, antibiotic wipes do not appear to help us and, it may be that they are actually hurting us.

The devil on my shoulder suggests we need to take the radical step of actually thinking for a second about what happens when you wash your hands, or whatever other part. This is a step almost never taken in the study of illness. Our skin (just like Lady Gaga’s skin) is covered in bacteria species. More than a hundred species of bacteria (not to mention fungi and other kinds of organisms) can be found on a single hand of any given adult [5] or for that matter belly button, forehead or other part, at any given moment (Image of some of the more abundant bacteria in the author’s belly button: ). It appears that those species include two main groups. There are the "native" species, our own bodily citizens that have evolved to live in peace on our skin and, in doing so, benefit us by acting as a kind of defensive layer. Then there are the tourists. It is these tourists that cause us harm, the tourists who bear chemical knives.

When you wash your hands, the goal is not to kill all the microbes. As Larson and a group of colleagues put it in a 2003 paper "Handwashing with a non-antimicrobial soap does little to modify the natural [citizen] flora. In fact, such an effect would be undesirable." What is desirable is, instead, to kill the tourists who have just turned up but not yet established, or at least the dangerous among those newly arrived species. Kill the tourists is a reasonable hand washing motto (although the truth is we still know surprisingly little about the citizens; they are the neglected serfs of our bodies). Soap is thought to be effective at killing the tourists, not always, but at least often, although this hypothesis has never been directly tested.

But what do antibiotic wipes and soaps do? Amazingly, no one really knows. In the vacuum of a laboratory they can kill both viruses and bacteria, but what about on the jungle of our bodies? It seems possible that they are able, in some cases, to kill both some of the tourists AND some of the citizens. Perhaps (which is to say, I am mostly guessing for the rest of this paragraph) when we are mostly healthy, this doesn’t matter; the bacteria regroup and recover or our body in other ways defends. But when we are already unwell, it may be that this is enough to make us more unwell by killing both natives and tourists and, in some cases, allowing the weediest tourists to recolonize first. Maybe, but this is just my scientific intuition which, let’s be honest, needs to be as carefully doubted and picked at as with our intuitions more generally.

What we do know is that the influence of these wipes and salves does not end with our hands, but instead spreads from them down our drains and out into society. What happens when antibiotic soaps and suds go down drains? To find out, a group of scientists recently made artificial drains clogged with bacteria (oh, the difficulties of science) and then subjected them to low and high doses of triclosan (similar to what happens when your detergent goes down the drain). Even at high concentrations, triclosan appears to have no effect on the number of bacterial cells in our drains. BUT, it does affect which species are found there. Triclosan kills "weak" bacteria but favors the tolerant, among them species of bacteria that eat triclosan [6]. Yes, I said eat triclosan. Triclosan may also favor lineages of bacteria that are also resistant to the oral antibiotics used in hospitals and elsewhere [7], though how often and consistently is, as of yet, unclear. Nonetheless, the hint of the tougher future triclosan might be favoring is, perhaps, a bit troubling.

Nor are drains the end of the story. Triclosan continues its journey, the little chemical that could, on to sewage treatment plants and into water supplies. In many municipal water supplies triclosan can now be found in relatively high concentrations. Those high concentrations affect the microbes that are always present in water, but also appear to act as endocrine disrupters in fish. For example, fish exposed to triclosan have lower sperm counts than those that are not [8]. Even if you don’t care about the sex lives of fish, this might still worry you, given the great similarities, on evolutionary grounds, between the hormones of fish and humans [9].

But I apologize. All of this was a diversion from the original story of the man with the cart, the man wringing his hands. This story digressed from his story, just as the consequences of his choice appear to cascade away from him out into the world.

The man continued on into the store, pausing only briefly to look at me, as if maybe he knew me. Then I saw that he was looking at my son. I looked at my son too, which is when I saw his marshmallow covered hands. I mouthed sorry back to the man, having realized, of course, that it was my cart he had first taken. My son would have mouthed sorry too, if he talked yet, and if his mouth wasn’t so gummed up with marshmallows.

"Sorry…," I was going to mouth again, but then he was gone and we needed to be going too, to get home and eat, after washing our hands, but just with good old fashioned soap. I’ll abandon the antimicrobial soap, detergent, and wipes. And I am pretty sure that I have never purchased the other antimicrobial products, whether the counter tops or underpants. This may seem sad, as though we have lost the war on the bad bacteria and viruses, those tourists with their counterfeit visas. If it does, I extend my apologies to you too. What is worse is that we seem to have lost it at a terrible time, what with all of the gross shopping carts and, more seriously, the reality that last year 2 million people died of respiratory infections. The good news, though, is that scientists have figured out a way to reduce the frequency that people get sick by as much as forty percent.

It turns out that although we know that washing our hands prevents a range of illnesses and are incredibly eager to buy products marketed to kill germs, we don’t actually take the simpler measure of washing hands in the first place. A study of nearly eight thousand individuals in five U.S. cities found almost half of the participants failed to wash their hands after going to the bathroom. In this light, no mystery salve is necessary, no miracle cure, special wipe, or magic. We need to wash our hands, because soap does the body good, at least in all the ways studied so far. It is not fancy. It is not expensive or heavily marketed and yet it works, as it long has, even though as of yet, no one can conclusively, unambiguously, tell you why.


[1] Those who are ignorant of cart history are doomed to repeat it.

[2] Aiello AE, Coulborn RM, Perez V, Larson EL. 2008. Effect of hand hygiene on infectious disease risk in the community setting: a meta-analysis. Am J Public Health 98:1372-1381.

[3] Luby SP, Agboatwalla M, Painter J, Altaf A, Billhimer WL, Hoekstra RM. Effect of intensive handwashing promotion on childhood diarrhea in high-risk communities in Pakistan: a randomized controlled trial. JAMA. 2004;291:2547–2554.

[4] Larson EL, Lin SX, Gomez-Pichardo C, Della-Latta P. Effect of antibacterial home cleaning and handwashing products on infectious disease symptoms: a randomized, double-blind trial. Ann Intern Med. 2004;140:321–329.

[5] Fierer, N. M. Hamady, C.L. Lauber, R. Knight. 2008. The influence of sex, handedness, and washing on the diversity of hand surface bacteria. Proc. Natl. Acad. Sci, USA. 105: 17994-17999.

[6] McBain, A. J.; Bartolo, R. G.; Catrenich, C. E.; Charbonneau, D.; Ledder, R. G.; Price, B. B.; Gilbert, P. Exposure of sink drain microcosms to triclosan: Population dynamics and antimicrobial susceptibility. Appl. Environ. Microbiol. 2003, 69, 5433−5442.

[7] Aiello AE, Larson EL. Antibacterial cleaning and hygiene products as an emerging risk factor for antibiotic resistance in the community. Lancet Infect Dis. 2003;3:501–506.

[8] Raut, S. A., and R. A. Angus 2010. Triclosan has endocrine-disrupting effects in male western mosquitofish, Gambusia affinis. Environ Toxicol Chem 29: 1287–1291.

[9] Rees Clayton, E.M., Todd, M., Dowd, J.B., Aiello, A.E.† (2010) The impact of bisphenol A and triclosan on immune parameters in the US population, NHANES 2003-2006. Environmental Health Perspectives


Image Credits: Bacteria cartoon, colorful shopping carts, Cart wipes, Triclosan ingredient, BioFresh mushrooms.

About the Author: Rob Dunn is a science writer and biologist in the Department of Biology at North Carolina State University. His first book, Every Living Thing, told the stories of the sometimes obsessive, occasionally mad, and always determined, biologists who have sought to discover the limits of the living world. His new book, The Wild Life of Our Bodies, explores how changes in our interactions with other species, be they the bacteria on our skin, forehead mites or tigers, have affected our health and well being. Rob lives in Raleigh, North Carolina with his wife, two children, and lots of microbes.

The views expressed are those of the author and are not necessarily those of Scientific American.

Comments 28 Comments

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  1. 1. biobabbler 11:53 am 07/5/2011

    Ah… thank you SO much for this article. Having taken bacteriology in school, when I first saw the antimicrobial craze starting, I thought "Oh, noooo!"

    I especially appreciate that your writing is SO engaging and fun that I expect far more people will read further into the article than otherwise would be the case. YAY!

    Due to my professor (who said take antibiotics as infrequently as possible, take the same kind every time, & ALWAYS TAKE THE FULL DOSE WHEN YOU DO), my doctor now calls me non-compliant re: antibiotics. =) I only take them when I REALLY have to. But I always take them all.

    And I buy antimicrobial nothing. All natural stuff.

    I remember walking around San Diego once, after a rare rain storm, and seeing the puddles in the pavement and realizing, woah, the kids in these neighborhoods might have NO ACCESS TO MUD! No mud pies, no delightful hours spent with dirt and hose creating all kinds of magical messes, all the while LOADING up on micro-flora and fauna. Not good on so many levels. No wonder city people are frequently afraid of dirt. They haven’t learned that dirt is your friend!

    =) Thanks again. GREAT stuff.

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  2. 2. J'Carlin 12:40 pm 07/5/2011

    Quite a while ago a dermatologist said "No soap." "Anywhere, anytime." "Except if you must in the stinky areas." I followed his direction, with careful feedback from the family on how I smelled, etc. Result: Better health in all areas, no socially unacceptable odors. A relatively long hot shower with lots of water on the stinky areas including hair, and I do fine. A side benefit, I cut easily and carry bandages in my wallet. If water is available I rinse the cut with hot water for a minute or so. No soap. No antibiotic. and cover it with the plain bandage. If no water handy just the bandage. I can’t remember the last infected wound. Except one treated by an MD in a hospital with all the usual antiseptic procedures. It seems my white cells have all the usual suspects ready to shoot first and question later.
    The way I see it the body has had tens of thousands of years to deal with infections and cuts. In general I let it do its thing.

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  3. 3. Pazuzu 3:59 pm 07/5/2011

    Echoing biobabbler, great article! Two questions: We live in the Adirondack wilderness and have a septic system. Any evidence on whether or not triclosan retards the septicity (is there such a word?) of septic systems?

    Second, I assume these comments don’t apply to alcohol based hand sanitizers, at least in terms of societal effects, right? Alcohol evaporates immediately and doesn’t end up down the drain. But I guess it kills both the tourist and the resident critters on our skin. I’d appreciate more info — or at least educated guesses — on this, because I’ve been avoiding triclosan for common-sense reasons, yet I use alcohol based hand sanitizer routinely. As an elderly person with COPD and asthma, I don’t want to make too many mistakes in this area.

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  4. 4. NeuroJoe 5:28 pm 07/5/2011

    "There was little evidence for an additional impact of new products, such as alcohol-based hand sanitizers or antibacterial soaps compared with nonantibacterial soaps, for reducing either gastrointestinal or respiratory infectious illness symptoms."

    The better control for alcohol based sanitizers would be no soap at all, since they are typically used in places where no soap and water is available. Also, do micro-organisms develop the same resistance to alcohols as they do for triclosan? That would be important to know.

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  5. 5. Sigmatize 6:18 pm 07/5/2011

    What about plain “elbow grease” and water? Could using a washcloth, with plenty of water be just as effective as soap and water? It’s been shown that residual bacteria on wooden cutting boards are destroyed by shearing forces produced by adhesion to micro cellulose fibers.

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  6. 6. redfield 9:06 pm 07/5/2011

    And did you use one of those wipes to clean the marshmallow off of the cart handle before you left?

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  7. 7. EyesWideOpen 9:48 pm 07/5/2011

    That tiny little statistical difference between "ordinary" handwashing with soap, and using anti-viral anti-bacterial anti-fungal treatments during or after real handwashing, could mean life or death.

    TB or other transmissible disease, even in tiny quantities (assuming "tiny" is relative because too tiny to be visible could mean millions of reproducing organisms) could be the difference between health and death.

    Now before we go green, consider. If I get TB or other crippling illness, because I didn’t go the "extra mile" in an age of deadly pathogens, maybe I protected fish from laying less eggs or worse, sterility. In the meantime, my hospital disposed of so much of my bio-contaminated waste (and all the hospital produced anti-pathogenic chemicals generated during my illness) that fish problems pale in comparison to landfills receiving waste marked in "Bio Hazard" marked containers.

    But I know, some might consider what I just said, as they say, "neither here nor there." I digressed!

    The bottomline is that health is priceless. "A little more healthier" (even a fraction of one percent healthier) therefore is also priceless, because that little improvement times infinite equals infinite! (For example, five percent improvement of infinite still equals infinite improvement.)

    I know, I’m singing to the choir. Duh?

    Many environmentalists are thinking that is beside the point! Pathogens are nature’s way of controlling the population! It’s a sort of "lottery" where, provided I don’t cheat and use anti-pathagenic chemicals to avoid that tiny but infinite probability of getting a fatal illness (TB or other), that when "my time is up," well, it’s up! How dare I try to cheat mother nature, who may have naturally decided my time on this earth is up, by bypassing her natural selection process in using technology that is guaranteed to kill 99.99% of viruses (including HIV, Ebola, et al), bacteria (TB and others), and fungi (clamidia et al)? My arrogance in buying scientifically proven products like DepHyze, Madacide, and others from lab supply companies or Amazon on the web!

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  8. 8. epostma 11:43 pm 07/5/2011

    @EyesWideOpen: as that the article mentions, the actual studies in hospitals indicate that non-antimicrobial soaps have an ever so slightly *better* health effect than soaps including triclosan. Therefore, by your reasoning, you should use non-antimicrobial soaps, *even* if it’s what those darned environmentalists suggest.

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  9. 9. gnomricon 12:26 am 07/6/2011

    How does the same not hold true for handwashing? Aren’t we just breeding lather-resistant superbugs?

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  10. 10. Pazuzu 9:08 am 07/6/2011

    OK, it appears that the general conclusion is that simple soap, water, and elbow grease is the best procedure for hand washing. And, @gnomricon, I doubt your conjecture, because simple soap acts as a surfactant in conjunction with water, and removes dirt from your skin. It presumably doesn’t kill microbes, just displaces them to where they’re harmless.

    I still want to know if small amounts of anti-microbial products will harm my septic system — it’s hard to avoid these products entirely.

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  11. 11. daedalus2u 10:02 am 07/6/2011

    It isn’t even clear that using soap and water (other than to prevent hand-to-mouth transmission of disease) is helpful either.

    The problem is that there is no data. Because bathing with soap and water is essentially universal, the only microorganisms that can be found on humans are those which are not removed completely by bathing.

    The commensal bacteria that I am working with (autotrophic ammonia oxidizing bacteria (AOB)) are removed essentially completely by bathing and they don’t grow back in a few days. They have a doubling time of ~10 hours. It takes 30x times longer for them to grow back than it does for all the “weeds”, a few months instead of a few days.

    With similar removal kinetics via bathing, only the fastest growing bacteria can repopulate the skin once bathing removes everything. It is like clear-cutting a forest. The first things to grow back are the “weeds”. The climax species take much longer to recover, but it is the climax species that produce the stable ecosystem.

    Our bodies didn’t evolve under conditions of daily, weekly, monthly or even yearly bathing. Our ancestors in Africa never bathed. They couldn’t because of the parasites in the water, and the large predators, crocodiles and lions that hunt around water sources where prey congregate. The skin flora that will produce the best health is the skin flora that our bodies evolved to have. That would be the climax species, not the “weeds” that recover the fastest.

    Gnomricon, yes, washing does foster the evolution of superbugs that are resistant to being removed by soap and water. But that evolution has already happened. Those are the bacteria that are now found on the skin of humans who bathe, the “weeds” that have developed tolerance to being removed and that then grow back the fastest. Most diseases that are transmitted by hand-to-mouth transfer only cause disease because they stick to the inside of the gut. That is a very different environment and requires very different properties than sticking to the hand.

    My hypothesis is that AOB are actually beneficial, in that they produce NO and nitrite in response to physiological release of ammonia, which physiology has evolved to utilize and can’t get any other way.

    They also suppress heterotrophic bacteria which cause skin infections.

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  12. 12. daedalus2u 10:03 am 07/6/2011

    One reason I was very interested in the BBP, is to see what is growing on me, because I am pretty sure I have a climax flora on my skin (I haven’t washed my flora off for several years now). My sample was #966. I suspect it is completely different than all the others.

    Even small amounts of antimicrobial compounds can have adverse effects by fostering antibiotic resistance. Many antimicrobial compounds foster cross-resistance to antibiotics that are used to treat diseases. Even pine oil fosters cross-resistance.

    You don’t want to put pressures on bacteria to evolve resistance to being killed by chemical agents because in most cases that will foster antibiotic resistance. It isn’t necessary to kill bacteria to prevent adverse effects. Bacteria only express virulence factors when they are at a high enough concentration so that they detect quorum sensing. Suppress quorum sensing and bacteria won’t cause disease, even if they are a virulent strain. This is how most eukaryotes prevent biofilms of the pathogenic bacteria they don’t want, they foster the growth of biofilms of non-pathogens (such as AOB), and the AOB suppress the quorum sensing of pathogens so the pathogens never take hold.

    It is like the climax ecosystem of the old growth forest. The big, old, and slow growing trees block the sunlight that the “weeds” need to grow, so the “weeds” can never get a foothold and take over. But if you clear cut the forest, it takes multiple duplication times of the slowest growing climax species to get back to the steady state climax forest, multiple centuries in the case of a forest, months in the case of human skin (and then you need the right inoculation too).

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  13. 13. aidel 10:06 am 07/6/2011

    Yes, yes, you have a point. Much of the cleaning of hands (for example) is accomplished by the mechanical act of rubbing them together and rinsing. Elbow grease is also a good answer for cutting boards and surfaces.

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  14. 14. aidel 10:16 am 07/6/2011

    Excellent and important post. Thank you so much for writing it. What you say is absolutely true — that we are not doing ourselves any favors with the ubiquitous anti-bacterial soaps/foams/wipes, etc. Of course, washing hands with regular soap and water continues to be ESSENTIAL for avoiding illness and basic hygiene. But even when we perform foley care in the hospital (cleaning the area where the catheter in your bladder enters your body), multiple studies were done and using regular washcloth, soap and water proved to be the best method for reducing infections (UTI). Of course, as a rule (and it is a rule!) in hospitals we do (and need to) use anti-microbial soaps/foams because there are huge numbers of bacterial and viral "visitors," especially antibiotic ones — and the number one culprit for nosicomial infections? Poor hand hygiene.

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  15. 15. daedalus2u 11:26 am 07/6/2011

    The problem with your facile analysis is that one of the things that prevents infection by pathogens is a good biofilm of commensal organisms. You can’t render your skin sterile, expose it to the external environment and expect it to stay that way. What ever bacteria get on your skin first will colonize it and proliferate. What do you want on your skin? What ever random weed or pathogen gets there first? Or something that is actually helpful?

    When antibiotics are taken, often there is disruption of the normal flora, which is why yeast infections and C. diff infections are common following antibiotics and rare without antibiotic use. The commensal bacteria that the antibiotics knock-out were keeping the yeast and C. diff suppressed. Without that suppression, the pathogen can proliferate enough until it expresses quorum sensing and causes disease.

    A healthy ecosystem (like an old growth forest) is more resistant to upsets than is a recently clear-cut forest. The same is true of the ecosystem that comprises our skin or gut.

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  16. 16. Anonymous20814 1:58 pm 07/6/2011

    Congratulations, you can make a fragment of a literature review into a complete waste of time. The sensational title is not earned by such weak and diffuse support.

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  17. 17. maduceone 5:18 pm 07/6/2011

    I "tested" this at home! When using anti-bacterial dish soap, sponges started to smell "musty" after only a day or two of use. Using a mild bleach solution to solve this worked for a day or so and then smell got worse. Switched to dish detergent which did NOT say anti-bacterial. Now, musty odor gone and sponge use longer. I assume that anti-bacterial detergent was killing all bacteria, which let mold (fungus) grow causing odor. Chlorine made worse (recent report on "corked" wine confirms something similar). For quick disinfectant of hands, I use "rubbing" alcohol (isopropyl) and distilled water in small sprayer. Also good for cleaning my glasses and is cheap, too. Vinegar/water has replaced using ammonia and chlorine based cleansers for a lot of household cleaning. Chlorine also overkills bacteria and allows certain molds to grow (I’ll have to look up where I saw corked wine article) in day-to-day use at home.

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  18. 18. ssm1959 6:23 pm 07/6/2011

    One of the earliest studies on this issue was carried out by P&G. They distributed bar soap to a group of untouchables in Mumbai and tracked GI problems in young kids. Bar soap alone dropped the incidence by over 50%. P&G repeated the study with Triclosan containing soap, and regular bar soap. Both achieved similar reductions but the tendency in the data showed a slightly higher incidence of acute GI problems in the Triclosan using group. Being industry generated research, the tendency was explained away as variance and the test was not repeated. However we must entertain the possibility that the introduction of a selective agent either pushed the bacterial population to a more virulent status or the Triclosan disrupted protective biofilms which opened the door to infection.

    Until the last 10 years we have been ignorant of the complexities and nuance of protective/pathogenic biofilms. We are sitting at a time where much of our understanding of human disease will be revolutionized by our newfound understandings in this area. However we know enough to consider limiting the use chemicals like triclosan in applications where the potential costs out weigh any meager benefits.

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  19. 19. limonoid 7:18 pm 07/6/2011

    Nice article but…. Don’t just stop at hand washing. Many years ago I ran a sterile products manufacturing suite. Whn I arrived all sorts of harsh disinfectants were used to maintain sterility within the suite. After extensive monitoring and testing the most effective cleaning routine used a high quality detergent, hot water and sterilised mop heads. Bacterial counts were a fraction of that achieved with disinfectants. Moral – clean dry surfaces don’t harbour bacteria (earth shattering that !). By all means clean that sticky cart handle but don’t waste money on antiseptics.

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  20. 20. syellahB 2:53 am 07/7/2011

    really? I thought, soaps can clean us and remove bacterias in out body. I can’t really believe on it!

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  21. 21. syellahB 3:25 am 07/7/2011

    How safe are we when soaps can cause bacteria too? no doubt, <a title="Transformative lessons learned from navel bacteria" href="">New belly button bacteria furthers study of evolution</a> as it is called bacterial nature reserve. Cleaning habits – or lack thereof – have made amazing discoveries possible. As few people wash their belly buttons with soap, the chance for microbial growth increases. It was suggested that there may be links between belly button bacteria and microbes that have previously only been found on the deep ocean floor. This opens entirely new avenues of inquiry within the study of divergent evolution, the accumulation of differences between groups which can lead to the formation of new species.

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  22. 22. StephanieP 4:55 am 07/8/2011

    The researchers have recorded a large number of new microbes. Navels can be hot and ticklish. The facts are that not everybody goes in there with cleansing soap, baby oil and Q-Tips. Experts at the Belly button Biodiversity project are depending upon that lack of care, as the microbes remaining behind are too fascinating to ignore. It’s a true story about divergent evolution, and it’s a page-turner. I read this here: <a title="Brand-new belly button bacteria furthers study of evolution" href="">New belly button bacteria furthers study of evolution</a>.

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  23. 23. SaraComito 2:54 pm 07/22/2011

    How can I dispose of triclosan-containing soap? I receive a lot as a gift from a well meaning relative. I contacted both the EPA and the FDA, and no one could give me an answer. I would appreciate it!

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  24. 24. ermesy 12:00 am 07/26/2011

    I believe bacteria are developing resistance to alcohols. Here in Australia public hospitals are starting to use a combination of alcohol and chlorhexidine based antiseptic handwashes because it was found that alcohol-only washes were simply not as effective as they used to be.
    We, too, are bombarded with ads for these ridiculous supermarket hand wipes and hand washes all trumpeting how they kill 99.9% of bacteria. You don’t need to be an evolutionary biologist to know that it’s the .1% of the surviving bugs that will go on to cause problems.

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  25. 25. daedalus2u 11:31 am 07/26/2011

    Alcohol kills by cell membrane disruption due to the alcohol dissolving in the lipid membrane. Bacteria in non-spore form cannot survive cell membrane disruption. When alcohol evaporates there is no residual toxicity. Bacteria cannot evolve resistance to high concentrations of alcohol without radically changing their cell membrane which would cause all of their membrane bound proteins to not work properly. A surface sterilized by alcohol can be recolonized as soon as the alcohol has evaporated or has been diluted to levels that are non-membrane disrupting. The reason that beer and wine can only be fermented to certain alcohol contents is because the alcohol disrupts the membranes of the yeasts producing the alcohol. No yeast has been able to evolve the ability to produce 50% alcohol and likely never will. That level is just so high. If bacteria could evolve to survive 50% alcohol, they likely would have very poor growth in normal body fluids and so could not be pathogens (which is all that really matters).

    Chlorhexidine also kills by cell membrane disruption but by a different mechanism (chlorhexidine is cationic and disrupts charge distributions and ion channels. Chlorhexidine does not evaporate, so it provides a residual anti-bacterial activity. Chlorhexidine is neutralized by things that are anionic, soap, and many detergents are anionic.

    Triclosan is a bad actor. It can form dioxins on exposure to sunlight in water. It probably can on incineration too. It is also an endocrine disrupter. You need to educate your well-meaning relatives that it is something you don’t want and will not use because it is harmful to you and to the environment. They should stop buying and using it themselves.

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  26. 26. basically 6:15 pm 11/4/2011

    Why do we want to kill a germ that is going to go down the drain when we wash our hands? Does someone think they are going to be healthier by using antibacterial soap? Why don’t we talk about exactly how soap makes us healthier? Soap works by breaking the attractive bond of fatty acid and oil molecules that are on the surface of the skin, thereby reducing the “stickiness” of them. The fatty acids and oils contain germs and dirt. The soap allows the h2o to wash the vast majority of this muck down the drain. I don’t think using a pesticide in the soap is going to increase the ability to wash the muck away. I think soap and water clean us by washing the muck away from our skin, although it may be that nonantibacterial soap kills germs by washing away their protective fatty acid layer anyway.

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  27. 27. ScienceDork=) 4:36 pm 03/27/2012

    so…….. no antimicrobial products???? I have to do a… an essay for language arts and it’s based on science (does that even make sense?) and i need some info. article helped lots:)

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  28. 28. defensesoap 11:27 am 02/16/2014

    If studies suggests that long-term exposure to triclosan could pose health risks, why take a chance? There are options available for natural soaps that are free from triclosan. here is full article on harmful effects of this chemical on health .

    Link to this

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