DISINFACTS | Issue 3/2020

14 Ethanol vs propanol Alcohol-based disinfectants The active ingredients in hand disinfection products are usually alcohol-based. The most commonly used active ingredients include ethanol, 1-Propanol and 2-Propanol (isopropanol). Depending on personal preference and intended use, a propanol-based hand disinfectant may be the product of choice or perhaps an ethanol-based product. Continue reading to learn about the differences between these active ingredients and how they are effective against viruses and bacteria! • What is ethanol? Ethanol is a water-soluble alcohol with two carbon atoms. Its molecular formula is C 2 H 5 OH. Ethanol (also called ethyl alcohol or "spirit") is commonly known as "drinking alcohol" and is thus an active ingredient in alcoholic drinks. At room temperature ethanol is a colourless liquid with a slight characteristic odour and a burning flavour [1]. • Advantage: effective against all non-enveloped viruses Unlike the two forms of propanol, which are effective against some non enveloped viruses (such as adenoviruses and noroviruses), ethanol is the only active substance effective against all non-enveloped viruses [2]. Care must be taken to ensure that the necessary exposure times are observed. • Things to know about efficacy When it comes to general statements about efficacy, the following should always be borne in mind: In addition to alcoholic active substances, hand disinfectants, such as the various Sterillium products, contain other ingredients (e.g. to improve skin tolerance). These also have an influence on efficacy. Without testing (using a specified method on prescribed test organisms) it is therefore impossible to predict the exact efficacy of a disinfectant formula against viruses, fungi and bacteria! • Advantage: recommended for sensitive skin The Commission for Hospital Hygiene and Infection Prevention (KRINKO) at the Robert Koch Institute in Germany recommends the use of ethanol-based products when treating particularly sensitive patients (e.g. newborns, small children, patients with respiratory diseases) [2]. One reason: Studies show that ethanol (80%) is better tolerated on the skin than 2-propanol (60%) [3]. This has led to the conclusion that applying ethanol to irritated or hypersensitive skin could be beneficial. Aggressive against proteins: How do alcohols work? The antimicrobial effect of alcohols is based on their ability to generally alter the structure of proteins [4]. The alcohol molecules damage the outer cell membrane, penetrate the cytoplasm and destroy the interior structure of the cell molecules and cytoplasm proteins. This process, called denaturation, and the coagulation of enzymes result in a loss of cellular activity and ultimately lead to cell death. Ethanol COMPETENCE H H H H CH H C O