Why Does The Alcohol Content Of Hand Sanitizer Need To Be 70 Percent?

It may come as news to some, but for hand sanitizer to be effective, it needs to contain a certain level of alcohol. Alcohol-based hand sanitizers are just one way you can mitigate your risk and prevent the spread of the coronavirus and other types of viruses and bacteria.

DIY Hand Sanitizer
Some experts warn against making your own hand sanitizer at home because there is simply no guarantee that hand made hand sanitizer will prove effective against pathogens that can harm you. However, with hand sanitizer shortages online and in physical stores, many have turned to make their own.
In addition to not knowing if enough alcohol was used in the hand made hand sanitizer, you may also not know if all the ingredients used in its creation are safe to use on human skin. If the concentration is not right, it can be too harsh, not effective at all, and also be a waste of ingredients.

Store-Bought Hand Sanitizers
Store-bought hand sanitizers typically contain the 70 percent alcohol content that is needed to ward off germs. These hand sanitizers typically contain denatured alcohol or isopropyl alcohol, glycerol or glycerin, hydrogen peroxide, and sterile water. An alcoholmeter is needed to measure the concentration of the alcohol to ensure it is the right concentration for killing germs and to make sure it is safe for use.

The Science Behind It
When a hand sanitizer has a lower concentration of alcohol or is not alcohol-based, it is simply not as effective. It will also not work as equally well on other types of germs. Some germs may even begin to develop a resistance against the hand sanitizer.
When pure alcohol comes into contact with protein, it coagulates. When it comes in contact with a single-celled organism, the alcohol goes through the cell wall of that organism and coagulates the protein inside the cell wall. The protein that has coagulated, however, stops the pure alcohol from going any further into the cell. So instead of killing the organism, it just becomes inactive.
If you have a strong alcohol solution of 70 percent or more, the diluted alcohol in the hand sanitizer can also coagulate the protein but at a much slower rate. This allows the alcohol to penetrate all the way through the cell before any of the coagulation can block it as it does with pure alcohol. Since the process is slower with a 70 percent alcohol-based hand sanitizer, the entire cell becomes coagulated and ultimately kills the organism.
Before you reach for that bottle of hand sanitizer, see to it that it contains at least 70 percent alcohol to ensure that you are killing organisms rather than just subduing them.

Meta: For a hand sanitizer to be effective at killing germs, it needs to contain at least 70 percent alcohol. If not, it can prove to be ineffective.