Soap is one of the main weapons (using a war metaphor) against SARS-CoV-2. From the World Health Organization down, everyone reminds us to often and properly wash our hands, to eliminate viruses and, in general, microorganisms that might harm us.
We take this simple product for granted, because of a daily use, but it has an ancient and prestigious origin. The first soaps date back to Babylonia, three thousand years before Christ. In 2800 b.C. Mesopotamia they weren’t used for personal hygiene, though, but as a tool to polish fabrics and hair, in order to increase the social status, or to cure wounds. From cuneiform inscriptions, historians were able to understand their preparation method, basically a mixture of water, cassia oil and other alkaline essences.
It seems, from the Ebers Papyrus, that the Egyptians knew that animal and vegetable fats had many properties but, even along the river Nile, soaps were used just for fabrics. Same way as China, where they had a soap “ancestor” obtained from animal fats and vegetable ashes.
Ancient Romans, for their bodies, used what today we would call a “scrub”: pumice stones and strigili, metal instruments that scratched off the layers of skin on which fat accumulated. Then they applied fragrances and essential oils – only those who could afford it, of course.
The word “soap” comes from Latin “sapo”, but it was used to describe, with a bit of contempt, the hair dye so popular among Gauls. It’s only during the II century a.D. that the Greek physician and philosopher Galen of Pergamon intuited a different utilization.
Progress toward the current soap came from the Arabs, that combined vegetable oils with soda or ashes, to obtain both solid and liquid compounds. Alep, in particular, has a flourishing production, thanks to the thriving cultivation of olive and bay trees.
Marseille soap comes from the Alep one. Soaps started to circulate in southern Europe through the Arab expansions in the Mediterranean sea in IX century and the Crusades, but it still was a luxury good. It will take more or less a thousand years before a large-scale deployment.
The first English experiments in the 1600s failed, for the cold process and a wrong baking soda dosage. In France, the studies conducted by the surgeon and chemist Nicolas Leblanc and by the chemist Michel Eugène Chevreul on fat acids lead to important steps towards industrialization.
The young Belgian inventor Ernest Solvay obtains significant improvements in 1861. At the age of 23, Solvay files a patent for a more widespread production. He even perfects the problem concerning pollution, connected to Leblanc’s method, in which too many hydrochloric acid and calcium sulphide were released.
Contemporary chemical studies on food sophistication brought results in another direction as well, contributing to the discover of the right amount of baking soda to use, to avoid damaging the epidermis.
Soaps lost their characterization of artisan luxury goods but helped to improve personal hygiene – together with modern sewer systems, bathrooms inside the houses and medical progress. This growing industry fund the newborn radio plays, destined to an audience of housewives, the main users of soaps and detergents in the 1930’s. That’s why the term “soap opera” was used until the 1990’s.
Although soaps, nowadays, are very cheap, there are exceptions. Cor is the name of the most expensive soap in the world, its price is of a dollar for a gram – against the few cents of a common Marseille – as it contains silver nanoparticles.
Costly, sure. But after all, as the German baron and chemist Justus von Liebig said in the 1800s, “the soap consumed by a nation is an accurate measure of its wealth and civilization”.