18 February 2009

Antibacterial soap is like bottled water.

Antibacterial soaps are bad for the environment, tend to create superbugs, and are ineffective! Cool! We've been sucked in by the marketing campaigns (again).

From the abstract by Aiello, Larson & Levy, "Soaps containing triclosan within the range of concentrations commonly used in the community setting (0.1%–0.45% wt/vol) were no more effective than plain soap at preventing infectious illness symptoms and reducing bacterial levels on the hands. Several laboratory studies demonstrated evidence of triclosan-adapted crossresistance to antibiotics among different species of bacteria."

But even apart from the antibacterial gimmick, soap has always been a bit of an enigma to me. Isn't this something we put on our skin? It's going to get absorbed into our bodies. Why do we use stuff that contains so many chemicals, perfumes, and colorants?

I've always had bad skin. My family used Dial soap, which probably made it worse. When I was in college, a friend suggested that I used Neutragena, and I switched completely to that, even for shampoo. For years, Neutragena was the best thing I'd found for my skin. Neutragena is expensive, though, so I'd occasionally try other soaps, but they freaked out my skin.

The cost of Neutragena really started to bother me, though. Here in NZ, it costs NZ$5/bar, way too much, and the stuff melts so easily that it was going down the drain too fast.

I found a cheaper New Zealand made "eco-soap" that had even won some kind of prize from the Ministry for the Environment. This did seem okay for my skin. On inspecting the ingredients, I noted that the supposedly "natural" soap contains EDTA, which is toxic. So why are we putting this on our skin? What does it mean to be "sustainable"? What is a "sustainable" soap? Certainly not something with antibacterial chemicals that persist in waterways.

As a somewhat desperate experiment, I tried making my own soap. I spent a lot of time researching soap making. Eventually, I found that making soap is easy, and the result is wonderful, at least as good as Neutragena if not better. Here's the recipe:

1. Go outside for this. Put 3/4 cup cool distilled water into a stainless steel pot. I don't use distilled water, just Christchurch's perfect tap water.

2. Pour in 1/4 cup sodium hydroxide (also called caustic soda or lye). Now you'll smell why you're outside - the fumes are nasty. Plus it will get hot. With a steel spoon, stir the lye until it dissolves.

3. Get a second pot. Put in 2 & 1/2 cups rice bran oil (which naturally contains lots of vitamin E). Now pour in the dissolved lye. Stir aggressively for 15 minutes. It really does take about this long. If you have an egg beater or electric stirrer, it will go faster. You'll see the mixture change in character and appearance, from translucent to opaque. Sometimes I heat it on a very low heat for a few minutes.

If the soap is crumbly, you need to add more oil, maybe a quarter cup at a time.  If the soap is oily, add more lye, maybe a half-teaspoon at a time.

4. Tip the goo out into a mold. I use a plastic ice cream container. Score the soap with a knife, so it's easy to cut later. Wait two weeks, and use. It needs some aging, to ensure that the lye is fully used up.

Cost per bar: mainly the oil, about NZ$1, or US$0.50. No EDTA. No ineffective super-bug causing marketing-driven antibacterials. Just oil and caustic soda. No perfumes or colours. Even counting my own labour at an appropriately exhorbitant rate, I come out ahead.

Disclaimer: make and use at your own risk, etc. The recipe is mostly pinched from here.

3 comments:

Jo said...

pharmacy 101 - they used to required the making of standard potions!

Will try. BTW I found than Mike Hamel at Ginger Meg made mild shampoos - but at a price. Someone from the faculty obligingly picked a year's supply for me, boxed it and put it in my shipment at the airport. Still have some actually!

Maria Kirby said...

My soap experiment with KOH from leached ashes failed. Dave Kanis gave me some NaOH, but I've not tried it yet. Reading your blog is encouraging. I've got a whole recipe book for different soaps using NaOH.

dogsrule7 said...
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