All about hand sanitizer
In the current corona virus pandemic that is sweeping the world, washing hands is still better than using hand sanitizer, but both help prevent the spread of disease.
Here’s some handy information on hand sanitizer.
- 1. What is ‘hand sanitizer’?
Hand sanitizer, also called hand antiseptic, or hand rub, is an agent applied to the hands for the purpose of removing common pathogens (disease-causing organisms). Hand sanitizers typically come in foam, gel, or liquid form. Their use is recommended when soap and water are not available for hand washing or when repeated hand washing compromises the natural skin barrier.
- Types of hand sanitizers
Depending on the active ingredient used, hand sanitizers can be classified as one of two types: alcohol-based or alcohol-free. Alcohol-based products typically contain between 60 and 95 percent alcohol, usually in the form of ethanol, isopropanol, or n-propanol. Alcohol-free products are generally based on disinfectants, such as benzalkonium chloride (BAC), or on antimicrobial agents, such as triclosan. Many hand sanitizers also contain emollients (e.g., glycerin) that soothe the skin, thickening agents, and fragrance.
Agencies such as the World Health Organization (WHO) and the U.S. Center for Disease Control and Prevention (CDC) promote the use of alcohol-based hand sanitizers over alcohol-free products. Indeed, the use of alcohol-free products has remained limited, in part because of WHO’s and CDC’s focus on alcohol-based products but also because of concerns about the safety of chemicals used in alcohol-free products.
- 3. Why is alcohol the main ingredient in most hand sanitizers?
Alcohol is effective at killing different types of microbes, includingboth viruses and bacteria, because it unfolds and inactivates their proteins.
- 4. How does alcohol-based hand sanitizer work?
Alcohols have long been known to kill germs by denaturing the protective outer proteins of microbes and dissolving their membranes.
CDC recommends using a hand sanitizer with at least 60% alcohol, as sanitizers with lower concentrations of alcohol aren’t as effective at killing germs. Even up to 90% alcohol is preferable to ensure that hand sanitizer completely kills germs rather than just reducing their growth on your hands.
- 5. If 60% alcohol is good, is 100% better?
Surprisingly, no. Protein denaturation actually works faster when a small amount of water is mixed with the alcohol. And pure alcohol would evaporate too quickly to effectively kill bacteria or viruses on your skin.
Using 100% alcohol also would dry your skin out very quickly. That might cause you to not sanitize your hands as frequently as needed. This is why most hand sanitizers contain emollients, which are mixtures that help soften and moisturize your skin.
- 6. Alcohol doesn’t kill some microbes very well — why not?
There are different types of bacteria and viruses, and some types are more easily killed by alcohol. For example, E. coli bacteria.
Differences in the outside surface of various bacteria make alcohol sanitization more effective against some of them than others. Similarly, some viruses have an outer wrapping, which is called an envelope, while others are non-enveloped. Alcohol is effective at killing enveloped viruses, including the coronavirus, but is less effective at killing non-enveloped viruses.
- 7. Hand sanitizer vs. washing your hands
According to the CDC, hand sanitizer is not as effective at killing germs as washing your hands with soap and water. The CDC says that washing your hands is a better way of removing certain viruses and bacteria, such as Cryptosporidium (causes diarrhoea) and norovirus (stomach bugs).
Part of the reason that hand sanitizer isn’t as effective as washing your hands is that people often wipe their hands before the hand sanitizer dries completely. Also, if your hands are dirty or greasy, hand sanitizers may not work because they can’t penetrate dirt and grease like soap can.
- 8. Can hand sanitizer protect you from viruses?
Hand sanitizerscan help protect you from infections — both viral and bacterial — when used correctly and in the right scenario. This means applying a hand sanitizer that is at least 60% alcohol, using the directed amount (read the label), rubbing it in completely and waiting for it to dry before doing anything else with your hands.