How Soap Works

Happy New Year for 2021! Kung Hei Fat Choi! Happy New Year of the Ox! In these weary days of COVID-19, ye olde bars of soap have stood the test of time! Medical experts have recognised such soap to be the gold standard for washing away the virus from our hands. Why so?

History First

Archaeological evidence proves that soap in bar form was first invented by the Babylonians in Mesopotamia. A formula for soap consisting of water, alkali, and cassia oil was written on a Babylonian clay tablet, in cuneiform script, like the one below, in around 2200 BCE.

The Ancient Egyptians were the first known civilization to use soap for healing and hygiene. They harvested alkali salts from the Valley of Natron, which is the namesake for sodium’s elemental symbol “Na,” then mixed them with animal and vegetable oils, as well as ash. The Ebers papyrus dated to 1550 BCE outlines using this mixture to treat skin diseases as well as for general washing. (Credit)

In the first century CE, the Romans preferred to anoint themselves with oil and scrape it from the skin after bathing rather than washing with a soapy lather. Galen (129–199/216 CE), a prominent Greek physician and philosopher in the Roman empire said, ‘All types of soap can severely loosen and remove all filth from the body’. This appears to be the beginnings of a doctor advocating skin hygiene by using soap. (Credit)

The Recipe

The basic recipe for making soap hasn’t changed for thousands of years. It is a mixture of animal or plant fat, or oil (which are mildly acidic/base substances), an alkaline (such as sodium hydroxide/lye – originally from wood ash) and water. When these three ingredients are combined in the right proportions, they undergo a chemical process, called saponification, and soap (a type of salt) is formed. (‘Sapo’ is from the Latin word for soap.)

The Nitty Gritty

Viruses are microscopic parasites, generally much smaller than bacteria. They lack the capacity to thrive and reproduce outside a host body. Humans can easily breathe them in since they are readily spread in air droplets, as we well know, and they like to stick to our hands when we touch contaminated surfaces, hoping to hitch a ride into our mouth, or up our nose.

Here is what a soap molecule looks like:

When you wash your hands with soap, the pin-shaped soap molecules in the soapy lather bond to oils, fats and the fatty lipid membrane of viruses via their hydrophobic tail ). Simultaneously, the hydrophilic head at the other end bonds to water molecules. When the, the push and pull, or friction, created by vigorously washing our hands (for 20 minutes as recommended by the World Health Organisation, WHO, and Centres for Disease Control, CDCs) dirt, oil, and germs are lifted from the skin and virus membranes are broken apart. By rinsing with clean water, they are all washed away. Handwashing is advised any time our hands come in contact with germs and viruses, such as after visiting the bathroom and after touching any surfaces outside your safe home environment.

The following illustration demonstrates how soap effectively breaks apart coronavirus molecules.

To see a demo on handwashing, and learn more about how soap kills the coronavirus click here.

Some people think that antibacterial soap is more effective in preventing the spread of viruses. Yet, there is no scientific evidence that it is better than plain soap. In fact, many studies have found that it will do us more harm than good in the long term, due to the questionable added chemicals.

GENERAL DISCLAIMER

The contents of this sharing are for informational purposes only. It is not intended to be a substitute for professional medical advice, diagnosis, or treatment . . . Read More →