Disinfectants, antiseptics and sanitizers are all chemical substances that kill microorganisms. These are microscopic organisms, like bacteria and viruses. The difference between disinfectants and antiseptics is important in medicine, as they are used on different types of surfaces.

Disinfectants

Disinfectants are chemical substances that kill (bactericidal, fungicidal) or inactivate (bacteriostatic) micro-organisms. Some examples of microorganisms include bacteria, viruses, germs or fungi. 

Disinfectants work in around 10 minutes after application. The important distinction is that they are used on non-living objects, such as countertops or clothes.

Antiseptics

Antiseptics have the same action but they are used on living things. They might sometimes be referred to as skin disinfectants. A doctor might rub his hands with an antiseptic before surgery. Certain throat lozenges and mouthwashes contain antiseptics to kill harmful bacteria from your mouth.

Disinfectants and antiseptics are effective against all micro-organisms, except for bacterial spores. These are copies of the bacteria’s genes in an inactive state. The genes enter this state when they are exposed to dangerous conditions. When the bacteria get out of these dangerous conditions, their genes may activate again. When their genes are active, the bacteria are infectious. 

In order to kill these spores, sterilization can be used. Sterilization kills all microorganisms, so it is often used in hospitals. It can be done by different methods, such as heat.

Sanitizers work more quickly than disinfectants.  It usually takes around 30 seconds for them to kill bacteria. They are not as effective against all micro-organisms. However, they are a quick and efficient way to protect yourself, especially when you don’t have access to soap or water. The word sanitizer is used for substances that work on objects and on living tissue.

How do hand sanitizers work?

Most hand sanitizers contain an alcohol solution. They might also contain fragrances and glycerin to protect your hands from becoming dry from using them.

On the label, you might commonly see names of different alcohols, such as ‘ethyl alcohol’, ‘ethanol’, ‘isopropyl alcohol’ or ‘n-propanol’. These are thought to work by damaging the structure of the bacteria and its proteins. The alcohol might also inhibit the production of molecules essential for bacteria to reproduce. In this way, the number of bacteria is stopped from growing.

In order to be able to kill the microorganism, the alcohol must be diluted with water. The most efficient sanitizers contain 60%-90% alcohol. You can check the percentage on the label. It is also important to use the right amount and wait for it to properly absorb before you start doing anything else.

Are sanitizers or antiseptics toxic?

Although it is not recommended to use certain antiseptics for long periods of time (as they can irritate skin) there is no need to worry about using a hand sanitizer. It might actually be less irritating than repeatedly washing your hands with soap!