. However, even if they do not have an antibacterial action, the soaps are able to break down the microbial load on the surface layer of the skin, rubbing and rinsing thoroughly.
Dirt remains trapped in the surfactant molecules. The surfactant molecules present in the soap are amphiphilic: composed of a hydrophilic part and a lipophilic part, with polar and apolar chemical properties, which make the soap effective.
How long should hand washing take?
How long does hand washing have to take to be effective? The total recommended time is at least 20 seconds: 15 seconds of rubbing with soap, and 5 seconds of rinsing. According to detrmatologists, this seems to be the right time for the soap to perform its cleaning function, and for the surfactant molecules to intercept bacteria and viruses.
Recently, the WHO, in order to prevent Covid-19 infections, recommended increasing the time dedicated to each hand cleansing with soap and water to no less than 40 seconds.
How hand sanitizing gel works
Alcohol-based disinfectant gels feature ethanol (ethyl alcohol), and 2-propanol capable of dissolving viral lipid membranes such as those of the coronavirus. In addition to them, they contain humectants such as glycerol, propylene glycol and sorbitol, which help to avoid dehydration and dryness of the skin after skin contact with solutions with a high alcohol content.
There are three types of alcohol-based hand sanitizers on the market:
- liquid solutions
- semisolid gels
- wet wipes
However, disinfection is not always preferable to cleansing: even if hand disinfectant gels perform a "bactericidal action that the soap is unable to activate, they are not as efficient in removing grease or other dirt."
substances contained in soaps or disinfectant solutions.
Contact dermatitis with cleaning solution can be of two types:
- Irritative contact dermatitis (DIC), due to the removal of skin lipids by soap and alcohol gel. The normal skin barrier is weakened by frequent washing or use of alcohol gel and the altered skin tends to become inflamed.
- Allergic contact dermatitis (ACD) affects only those who develop an "allergy to an allergen, or more of the substances contained in soaps or alcoholic solutions, recognized as an enemy by lymphocytes, which then trigger the inflammation process of the part that comes into contact with allergens.
How to prevent disinfectant gel dermatitis
- Use alcoholic soaps or solutions that also contain an emollient.
- Dry your hands thoroughly before putting on gloves to prevent moisture from promoting dermatitis.
- Apply emollient creams to replenish the lipids lost from the skin during frequent cleansing and use of alcoholic solutions. Experts recommend applying the nourishing hand cream at least 3 times a day.
