Hand-disinfecting solutions: how to make them home

During this tough time, I have been thinking if keeping posting in the same fashion, if stopping writing or using the blog to address all your questions about disinfecting solutions, facial masks and so on…

Eventually, I decided to stick to the usual line of the blog, also to give a sense of “normality” to the times we are currently living. Once in a while, I will alternate special posts to address all your questions.

One of the most common queries I received concerns the alcohol-based disinfecting solutions. I was asked if they actually work and how to make them home.

As health authorities have indicated, washing your hands well remains an efficient method to eliminate viruses and bacteria. Below the WHO’s recommendations on how to wash your hands:

Wash your hands frequently

Regularly and thoroughly clean your hands with an alcohol-based hand rub or wash them with soap and water.

Why? Washing your hands with soap and water or using alcohol-based hand rub kills viruses that may be on your hands.
— https://www.who.int/emergencies/diseases/novel-coronavirus-2019/advice-for-public
 
 

Are alcohol-based solutions effective?

The alcohol-based gels sold in the pharmacies have a variable alcohol concentration, usually around 70%. They are usually prepared with ethyl alcohol, although isopropyl alcohol can be used sometimes. Alcohol-based gels have been deemed effective in the removal of bateria and viruses. Ideally, they should be use when water and soap are not available. Diluted alcohol is more effective than the pure one. In order to be effective, the alcohol concentration should not be below 60%.

How to make a hand-disinfecting solution at home?

WHO has published the recipe to make the disinfecting solution by yourself. The WHO’s recipe calls for hydrogen peroxide, which helps with eliminating the bacterial spores. Glycerin is not mandatory, it just helps maintaining the skin’s moisture.

If you want a simple-basic alcoholic solution to clean your hands, here’s the recipe:

  • 700 mL of denatured ethyl alcohol (90%)

  • 300 mL of water (boil it and let it cool down prior to use)

 
 

This solution does not neutralize the spores though, like those from clostridium tetani (the bacterium responsible for tetanus). Pay attention to the concentration of denatured alcohol you use (do not go below 90%), or you might have a solution that is too diluted.

Warnings

Even if alcohol-based hand-washing solutions are rather effective, they do not eliminate 100% of viruses and bacteria. Solutions made with just water and alcohol tends to dehydrate the skin, because they lack moisturizers.

Alcohol is flammable, be careful.

Do not start to mix and match! I received messages from people who mixed alcohol and bleach, in the attempt to obtain a “more effective” product. No, no and no! Do not play the “little chemist” at home. You might risk intoxication or to hurt yourself, and it is not to case to overwhelm our health system, in particular now. Be wise :)

Last, but not least, keep out the reach of children!