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Anti-Bacterial Soap No Better Than Plain Soap
eldavojohn writes to advise us to stop buying antibacterial soap, as it's no more effective than the regular stuff. And, using it introduces a risk of mutation of bacteria. From the article: "The team looked at 27 studies conducted between 1980 and 2006, and found that soaps containing triclosan within the range of concentrations commonly used in the community setting (0.1 to 0.45 percent wt./vol.) were no more effective than plain soaps. Triclosan is used in higher concentrations in hospitals and other clinical settings, and may be more effective at reducing illness and bacteria. Triclosan works by targeting a biochemical pathway in the bacteria that allows the bacteria to keep its cell wall intact. Because of the way triclosan kills the bacteria, mutations can happen at the targeted site... a mutation could mean that the triclosan can no longer get to the target site to kill the bacteria because the bacteria and the pathway have changed form."
what is a soap?
Anti-Bacterial Soap Sells Better than Plain Soap
Hurray for marketing!!!
Over the last few years it's become harder to find hand soap (at least the liquid type) that isn't antibacterial. The fad has pushed the added chemicals into all the major brands.
You can't talk about Wikipedia's flaws on Wikipedia
I've been saying for years that plain soap is good enough, and that it's bad for us as a species to use anti-bacterial soap. I have "body wash" in my soap dispenser in the bathroom, because all the "hand soap" is anti-bacterial these days.
Just goes to show that even an uninformed, loud-mouthed, opinionated jerk is right sometimes.
-Peter
From: Mayo Clinic Article 05 Dec 2005
It has been known for quite some time that it's the mechanical action that does an important part of the work for disinfecting your hands. The water and soap just help the process by carrying dirt and bacteria away. This is part of the reason that you don't see hand sanitizers allowed as a replacement for proper hand washing at restaurants and other commercial food prep areas.
Soap, a surfactant, kills using physics. It turns lipid membranes inside out. Also by reducing surface tension it creates other havoc (e.g. it suffocates garden insects who drown when their air-pores are blocked ). It's essentially impossible to evolve away from this without immense changes to the very design of the but. Sure it can be done but it's an enormous burden on the germ.
Chlorine kills with chemistry. It tends to react with a lot of things and even create radicals. It's a little easier to deal with for bugs since they encounter oxidizing environments naturally and have learned to adapt, but it's still so generic an attack that in high concentration it's very lethal and almost impossible to mutate away from.
Bacteria-cide works by biology, targeting some very specific feature of the bug that is mutable. The difference between antibiotics and "bacteria-cide" is largely the degree to which the target is mutable. Target the ribosome machinery and it's unlikely the bug can mutate in time--antibiotic. Target something less unique and primitive and the bug mutates eventually.
Some drink at the fountain of knowledge. Others just gargle.
You're right. If it's alcohol based, it will just dessicate the bacteria and there's no chance of developing resistance. That's why you see little purell containers around the hospitals now. Alcohol based cleaners are also (surprisingly) easier on your hands than the old water-and-soap method.
(I've got a degree in cell biology, and I'm a med student, so that's where my info is coming from)
I work in computational biology
So, you're studying the germs on your keyboard? They say your toilet seat is cleaner, but I don't think I would eat off of either one of them.
What?
My wife and I buy "soap base" in bulk and use it. It's intended to be mixed with fragrances and coloring (and I suppose resold) but we use it straight. It's very inexpensive, though you have to buy empty dispenser bottles to use it.
Here's the site we order from. There's no "anti-bacteria" chemicals in it, and for people like me who hate fragrances, it's hypo-allergenic without the boutique price. For a gallon, it's 25 cents an ounce. And it should last about two years per person. If you want something with an interesting label, go with Dr. Bronner's.
For those chemists (cooks) out there, soap is easy to make yourself.