How effective are alcohol disinfectants?

Alcohol as a beverage is quite popular amongst the masses. It is one of the most preferred beverages, especially during parties. It shares the top ranks along with other popular beverages like tea, coffee, and soft drinks. But are you familiar with alcohol disinfectants? If yes, are alcohol disinfectants really useful? It was the COVID-19 pandemic that showed the world, the other side of alcohol. The need for disinfection during the pandemic became much more important. Here’s where alcohol disinfectants came into the picture.

During the pandemic, alcohol-based disinfectants & sanitizers played a vital role. Why? It was because when the supplies ran dry, the stores were full of alcohol-based disinfectants due to the ease of alcohol procurement & synthesis. This allowed the mass production of alcohol disinfectants, even during the pandemic. Which alcohol is used in disinfectants? What is the concentration of alcohol? Is alcohol the active ingredient in these alcohol disinfectants? More importantly, during the pandemic, the effectiveness of alcohol disinfectants was questioned. 

So, in this article, we are going to briefly discuss such queries about alcohol disinfectants. We will also address the key query of whether alcohol disinfectants are really useful or not? So, let’s continue without any further ado. 

What is Alcohol? A beverage or disinfectant?

Alcohol

Scientifically (or to be precise chemically), alcohol is a type of functional group (also called hydroxyl group or -OH) attached to a saturated carbon atom (C). It is an organic compound with carbon, oxygen & hydrogen atoms. Generally, in our daily life, we consider ethanol (C2H6O) as alcohol. Ethanol is the primary constituent of alcoholic beverages. It is noteworthy that not all types of alcohol can be consumed. Many are toxic & hazardous to human consumption.

Check out for more information on alcohol. You must be wondering can someone use beer or vodka for disinfection purposes? Is it really useful? Keep reading to find it out.

Alcohol as a Disinfectant

Let’s talk more about alcohol as a disinfectant. Alcohol-based disinfectants contain alcohol as an active ingredient. This means that the disinfection is due to alcohol. Traditionally, different types of alcohols with varying concentrations were used. Currently, we use mostly only two types of alcohol. The first one is called rubbing alcohol, also called isopropyl alcohol or isopropanol. The second one is the famous & more familiar alcohol called ethanol. 

Now, you must be wondering, can we use vodka, beer, or any other alcoholic beverage as a disinfectant? The answer would be a NO! CDC recommends that any alcohol-based disinfectant should have at least 60% ethanol or 70% isopropanol concentration as the active ingredient. There isn’t any relaxation in alcohol content for hand sanitizers. At least 60% ethanol or 70% isopropanol concentration is necessary for hand sanitizers & their use is recommended only when a person is not able to access soap & water. Any alcoholic beverage seldom contains 70% concentration. So, using consumable alcohol for disinfection is not recommended.

Check out our blog to find detailed information on hand sanitizers.

Can ethanol or isopropanol kill pathogens? Are they really effective?

Yes. The reason behind using these alcohol types for disinfection & sanitization is their ability to neutralize pathogens. Firstly, alcohol is antimicrobial in nature. Secondly, if used in the right concentrations (around 60 to 90%) they act as an ideal disinfectant (when used properly). It is important to note that concentrations less than 60% alcohol isn’t effective disinfectant.

Pathogens consist of a wide range of bacteria, viruses, fungi, and other microbes. Alcohol is effective against most of these pathogens. It has been observed that a few microbes can resist alcohol. These pathogens develop resistance against alcohol and bypass its disinfecting purpose. During the COVID-19 pandemic, many studies found out that the coronavirus can be neutralized using alcohol disinfectants. On the contrary, alcohol disinfectants have been found infective against the virus that causes Hepatitis A but is capable of neutralizing the virus that causes Hepatitis B.

How does ethanol & isopropanol neutralize pathogens?

The reason behind the effectiveness of alcohol as disinfection is a chemical reaction. The reaction is called denaturation (of proteins). The reaction requires a minimum of 60% ethanol or 70% isopropanol concentration. This is the reason for alcohol concentration being above 60 or 70% (depending upon the type of alcohol) for disinfection purposes. But, it does not mean that the higher the alcohol concentration, the better the disinfection. This may or may not be true, and depends upon the pathogen. A study has proven if the alcohol concentration goes beyond 70% the disinfection capability reduces.

Pathogens contain proteins in their structure. Alcohol initiates the denaturation reaction of these protein molecules. In denaturation, the protein molecule crumbles & breaks down. This results in the collapse of the pathogen structure. The cells of pathogens start to malfunction, and this results in dehydration. Eventually, the pathogen dies. The factors which influence the disinfection procedure are the type of surface, type of pathogen, type of alcohol, and alcohol concentration. The combination of all these factors influences the effectiveness of alcohol for disinfection purposes.

FAQs

Can one consume ethanol-based alcohol disinfectant?

No. Alcohol disinfectants are not fit for human consumption. While it is true that ethanol is present in alcoholic beverages, the concentration & source of ethanol production makes the disinfectant unfit for human consumption.  

What precautions should one take while using alcohol disinfectants?

1. Alcohol is inflammable. Keep it away from heat & flames. Store it under shade & avoid direct exposure to sunlight.
2. Keep alcohol disinfectants away from pets & children. Children should use alcohol disinfectants under adult supervision.
3. Avoid ingestion of alcohol disinfectants. They are toxic & harmful to human health.
4. Always store alcohol disinfectants properly sealed. This prevents the evaporation of alcohol which effectively reduces its concentration.

How to disinfect using alcohol disinfectants?

Follow all the guidelines mentioned by the manufacturer. Here is a general routine that one can follow while using alcohol disinfectants.

1. Wear proper hand protection PPE such as nitrile gloves to protect your hands.
2. Ensure that the place is properly illuminated.
3. Preferably use soap and water to eliminate any dirt before disinfection of the surface.
4. The surface needs to be clean & dust-free. So, make the necessary changes on the surface.
5. Apply the alcohol disinfectant on the surface & leave it alone for at least 30 seconds.

Find out more information about hand protection PPE.

How frequently should one disinfect using alcohol disinfectants?

It depends upon the situation & the pathogen dealt with. If someone is ill, disinfection may range up to 2 to 6 times a day. While in the normal conditions, once while disinfection is also fine. Please note that the period of survival for the pathogen can cause an increase in the frequency of disinfection.

Is 70% isopropyl alcohol-based disinfectant more effective than 99% isopropyl alcohol-based disinfectant? 

Many studies have proven that the best possible disinfection by isopropyl alcohol is at 70% concentration. Higher concentrations of alcohol cause the coagulation of proteins (in the cell wall) and obstruct the entry of alcohol into the cell. This causes hindrance to the denaturation process. Higher concentrations of isopropyl alcohol can even increase the resistance of pathogens against disinfection. 70% isopropyl alcohol contains a higher amount of water when compared to 99% isopropanol. Water plays an important role in the denaturation process.

Check out the guidelines for disinfection by CDC.

Tip

Use alcohol disinfectants only for smaller surfaces. Using alcohol disinfectant for larger spaces can trigger evaporation of alcohol which does not provide enough time for the neutralization of pathogens. Reapplication of alcohol disinfectants is highly recommended.