There’s something comforting – and a little surprising – that simple soap is one of our most effective weapons against the coronavirus.
Mankind has been using soap for thousands of years. The ancient Babylonians were making it as early as 2800 B.C. Soap got its name from a Roman legend about Mount Sapo. It was said that rain would wash down the mountain, mixing with fat and ashes from animal sacrifices, resulting in a soap-like material. The recipe hasn’t changed much; soap is still made from fats and oils that react with lye (sodium hydroxide).
But why is something so simple effective against everything from dirt to viruses? The answer is that soap, on the molecular level, is rather violent. This New York Times article details why.
Essentially, soap is made of pin-shaped molecules. Each molecule has a hydrophilic head (meaning it bonds with water) and a hydrophobic tail, which avoids water in favor of hooking up with fats and oils.
When you wash your hands with soap and water, the soap molecules surround microorganisms on the skin, like viruses and bacteria. In trying to avoid water, the hydrophobic tails wedge themselves into the lipid envelopes of the microbes and viruses, breaking them apart and destroying them. Soap also disrupts the chemical bonds that allow bacteria and viruses to stick to surfaces, making it easier to wash them away.
Lather up and stay safe.