If you’re wondering whether alcohol — like ethanol or isopropanol — has the ability to kill germs on your skin and on surfaces in your home, the short answer is yes, it potentially can.
Alcohol has antimicrobial properties. This means that, at the right concentration (strength), it can destroy germs such as bacteria and viruses. But, as with most things, its effectiveness depends on various factors.
Let’s get into how well alcohol works at killing various germs, including the coronavirus that causes COVID-19 (SARS-CoV-2).
Can alcohol kill germs?
Alcohol kills germs through a simple chemical process known as denaturation.
Denaturation occurs when alcohol molecules break down the proteins present in the structure of germs. When the proteins break down and lose their structure, the cells can’t function properly. They lose their membrane protection, dehydrate, and quickly die.
This process is similar to what happens when you wash your hands with soap and water. However, soap is even more effective than alcohol.
The most widely used alcohol-based sanitizers contain either ethanol (ethyl alcohol) or isopropanol (isopropyl alcohol). Ethanol is chemically the same as drinking alcohol. You might have heard isopropanol referred to as rubbing alcohol.
Both are fairly effective at eliminating bacteria and viruses on your skin and on different types of surfaces. In general, ethanol is more powerful Trusted Source than isopropanol, although it depends on the type of microbe you want to kill.
The Centers for Disease Control and Prevention (CDC)Trusted Source recommends an alcohol concentration of between 60 and 90 percent for disinfection purposes.
When looking for products like household cleaners or hand sanitizers that can kill germs, opt for ones that indicate at least 60 percent ethanol or 70 percent isopropanol as an ingredient.
Keep in mind that these products aren’t meant to be consumed. They won’t help kill germs that are already inside your body. Plus, ingesting these products poses life threatening health risks.
Can alcohol kill all types of germs or only some types?
At the required concentrations — between 60 and 90 percent — alcohol can kill a broad range of germs, including bacteria, viruses, and fungi.
For example, alcohol can eliminate common bacteria, such as E. coli, salmonella, and Staphylococcus aureus. Other bacteria, such as Enterococcus faecalis, are becoming more resistant to the effects of alcohol-based disinfectants.
Alcohol has also been shown to kill viruses such as herpes, hepatitis B, HIV, influenza, rhinoviruses, and coronaviruses, among others.
A 2020 study indicates that alcohol effectively destroys SARS-CoV-2, the virus that causes COVID-19.
However, alcohol isn’t effective against destroying the viruses that cause hepatitis A or polio.
Finally, alcohol is also effective at destroying fungi, such as Blastomyces dermatitidis and Coccinidiodes immitis, which can cause fungal diseases.
How to use alcohol effectively for disinfection
When choosing an alcohol-based disinfectant, remember to look for a product with an alcohol content of at least 60 percent.
Keep alcohol-based products out of reach of children and pets. Also remember that alcohol-based products are flammable and should be kept away from flames. Keep these products sealed to prevent evaporation, which can weaken the concentration of the alcohol.
Follow the guidelines below when using an alcohol-based product to disinfect your hands or household surfaces.
For your hands
Before using a new hand sanitizer, check to make sure the product doesn’t appear on the list of hand sanitizers to avoidTrusted Source provided by the Food and Drug Administration (FDA).
Follow these steps to use an alcohol-based rub to sanitize your hands:
- Remove any dirt or debris from your hands. Alcohol-based sanitizers are less effective when hands are visibly dirty.
- Apply the sanitizer to one palm. A dime-sized amount of liquid should be enough (or if you’re using wipes, one wipe). If the product label indicates how much to use, follow that.
- Rub your hands together, making sure to cover all the skin on both hands, including the backs of your hands, your palms, your fingertips, and in between your fingers.
- Keep rubbing until the sanitizer has been absorbed and your hands feel dry.
- Reapply sanitizer whenever you would normally wash your hands but don’t have access to soap and water.
For household surfaces
Follow these guidelines to use an alcohol-based product to disinfect your home:
- Wear gloves to protect your hands, and ensure that you’re working in a well-ventilated area.
- Use soap and water to remove any visible dirt or debris before disinfecting.
- Read and follow all instructions on the product label.
- Wipe down the surface. Ensure it remains visibly wet for at least 30 seconds. Some products may offer additional directions.
- Remember that viruses such as the new coronavirus can live on surfaces for up to a week, depending on the surface. Clean frequently touched surfaces at least once per day — more often if someone in your home is sick.
What else can kill germs on your hands or surfaces?
Using soap and water is the best way to kill germs on your hands. To wash your hands, wet them thoroughly with water, lather them with soap, and scrub for at least 20 seconds. Then rinse and dry them.
If you don’t have alcohol on hand to disinfect surfaces in your home, you can use a wide range of other products, including bleach.
The Environmental Protection Agency (EPA) has a list of disinfectants known to be effective against SARS-CoV-2. When using a new product, check to make sure it’s on the list.
Can drinking alcohol kill viruses and bacteria?
Drinking alcoholic beverages such as beer, wine, whiskey, or vodka won’t help your body fight off an infection.
When you drink, the concentration of alcohol that actually enters your bloodstream isn’t enough to effectively kill germs. This is true even at blood alcohol levels associated with potentially fatal alcohol poisoning.
Drinking alcohol-based hand sanitizers or cleaning products also poses serious risks, including:
If you’re wondering whether, in a pinch, you can use an alcoholic beverage to disinfect your hands or household surfaces, you should know that it’s not an effective option.
Alcoholic drinks generally contain between 5 and 30 percent alcohol, so they aren’t effective as disinfectants. In addition, they aren’t formulated to remain on your skin or surfaces long enough to kill germs. This means they’ll likely evaporate too quickly to be effective.
The bottom line
At concentrations greater than 60 percent, alcohol effectively kills germs on your hands and household surfaces.
Microbes including bacteria, viruses, and fungi are susceptible to alcohol’s germicidal effects. This includes the new coronavirus that causes the respiratory disease COVID-19.
But alcohol-based sanitizers and disinfectants are not meant to be consumed. They won’t destroy pathogens inside your body.
It’s important to always follow the instructions on the product label for best results.