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Title: The Dirt on Soap
Article Summary: Soap is soap except when it's not soap. A discussion on the different types of soap we use on our skin.
Word Count: 856
First Published: 2001

Contact Info:
Paula Polman
paula@TheLearningCenterForEntrepreneurs.com
780-270-8146 MST
Edmonton AB Canada


So what's the big deal? Soap is soap, right? Mom always said to wash with it or sometimes she'd wash my mouth out with it. Bars, liquid, powder colours, scents, biodegradable, pH balanced, phosphates, antibacterial, moisturizing, drying, the list can go on and on. So many choices but what does it all mean?

Water by itself is a poor cleaner as it is restricted to removing only dirt that can dissolve or be suspended in it. Soap, broken down into its basic function, is a cleanser that emulsifies grease and grime, making it soluble in water and so washes it down the drain.

It is speculated that our ancestors of centuries back likely discovered soap when rainwater hit their refuse pits full of grease and ash, among other things. Pompeii had a soap factory near the resort and spa section of town, even the bible refers to "the lye of laundrymen" in Malachi 3:2. Pliny the Elder makes reference to soaps for hair as used by women in 77 AD. Our grandmothers made soap by mixing lye and animal fat in ratios attained by trial and error. Our great-grandmothers made lye by soaking fire ash in rainwater.

Fortunately these days we understand the chemistry a little better and can easily calculate the lye/fat ratios by something called a saponification (SAP) value. Chemically speaking, soap is simply an organic salt; the result of the reaction (hydrolysis) of a base (lye) with an acid (fatty acids). The two forms of lye most commonly used are sodium hydroxide (NaOH) and potassium hydroxide (KOH). Fatty acids are the building blocks of fat, be it vegetable or animal.

Fatty acids (triglycerides) have a molecular structure of a head with three tails. When mixed together with lye, the hydroxide (-OH) end of the lye chops off the head of the fatty acid and you end up with three molecules of soap (salt) from the separated tails and one molecule of glycerin. These chains of molecules now have the advantage where one end loves oils and the other end loves water. This allows the same molecule to attach to grease and to water, suspending the dirt in the water and allowing you to wash it away.

Natural soap retains all its glycerin, a humectant for skin. Commercial soap strips it out to make other products with it, including glycerin soap. Natural soaps often contain excess oils - more oil than the lye can turn into soap. This is often called superfatted soap and is extremely moisturizing to skin, however, it tends to be a softer soap than commercial soap as a result.

Most commercial soaps are not soaps at all, but chemical detergents made from petroleum by-products. Here is where you get into trouble with excess phosphates and biodegradeability. Natural soaps are biodegradeable and contain no phosphates. Phosphates are a by-product of detergents and are not biodegradeable. If it doesn't say soap on the label, then it isn't. Beauty bar, deoderant soap, skin/body wash, bath gels, liquid soaps, laundry detergents, etc are all made synthetically and often add in extra moisturizers, synthetic fragrances, dyes and chemical enhancers to improve both its mechanical ability and saleability.

Recently a well known brand of soap had a marketing campaign featuring the pH of their soap. 7.0 pH balanced was their claim and even sent out strips of litmus paper so consumers could compare their regular soap to the company's claim. Of course the litmus paper was the type that only reflected anything that had a pH higher than it's own product. The need for pH balancing is not as big a need as marketers would claim. Actually, bacteria on your skin thrive at a pH between 6 and 8. Cleansers that have a pH outside that range will actually be more effective cleansers than a pH balanced cleanser. The idea is to promote a hostile environment and the bad bugs either move on or are destroyed. Having said that, you certainly don't want to be dipping into a bath with a pH higher than 10 or lower than 4. However, we regularly consume soft drinks with a pH of 3-4 and the pH of natural soap tends to range in the 8-9 region. Definitely within the skin's tolerance range.

Antibacterial? Well if it's pH balanced to neutral (7.0) then it will need other bacterial killers added to the soap to be effective. Remember too that you don't want to kill off all your skin bacteria, as some of it is not only beneficial but necessary for healthy skin. Overuse of antibacterial products is not only a waste but a hazard as you encourage the development of resistance strains.

Scents and colours are added strictly for commercial appeal. The exception to this is when the scents are from essential oils and the colours are from the addition of herbs. The use of essential oils and herbs in skin care products not only smell nice, but if formulated properly, are highly beneficial to skin as well. The other choice is synthetic fragrances (fragrance oils and perfumes) and artificial dyes.

So what's the real dirt on soap? It's real soap.

Paula Polman, B.Sc. ran a natural cosmetics and toiletries company for 6 years and has been an entrepreneur for over 20 years. She is now involved in offering online instructional courses for small business at The Learning Center for Entrepreneurs, supporting the growth of small business thorugh extended learning. Email her at paula [at] TheLearningCenterForEntrepreneurs [dot] com or visit http://www.TheLearningCenterForEntrepreneurs.com

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