With the return to normalcy that the crisis of the new coronavirus is going to leave us, the businesses that little by little are opening their doors to the public, want to do it with the maximum guarantees for their clients and workers. Masks, gloves, systems to keep distance and avoid contact … and, of course, to disinfect thoroughly. To this end, the purchase of domestic ozone machines is proliferating, both to sanitize commercial premises and homes. However, in addition to the fact that ozone can become toxic if not handled properly, it is still uncertain whether or not this type of low-powered domestic appliance is effective against the virus that causes COVID-19.
Ozone (O3) is a powerful oxidant that has been used for more than 100 years to disinfect. This disinfection occurs because, when it comes into contact with impurities such as viruses, fungi or bacteria, the ozone is transformed into oxygen (O2), leaving a free radical with great antioxidant power. This radical reacts immediately with the nearest organic molecule and degrades it. If the concentration of the ozone is sufficient and during the necessary time, many of these particles will die or remain inactive. That is why ozone is used as a disinfectant, but mainly in the treatment of drinking water and in the food industry for disinfecting tools or closed rooms and even for disinfecting fruit and vegetables in the form of ozonated water.
However, the fact that it has great disinfecting and oxidising power does not mean that it is capable of killing off any dangerous micro-organisms. In fact, it has not been proven that ozone, even in large concentrations and with professional machines, is effective against the coronavirus, as recognized by the International Ozone Association, whose website states that “while ozone is highly effective for the inactivation of many viruses, the IOA is not aware of any research and testing that has been done specifically on the coronavirus SARS-CoV-2.
To our knowledge, the peer-reviewed research has not yet been completed and therefore no definitive conclusions can be drawn regarding the inactivation of SARS-CoV-2 ozone”, i.e. there are not enough studies to state that ozone is an effective viricide against coronavirus and therefore no organism recommends it for that purpose.
The domestic ozone machines that have become so fashionable in recent weeks are authorized, but not to be marketed as a disinfectant against the coronavirus, but to kill certain bacteria that generate bad odor or even to eliminate mites or fungi .
Furthermore, we cannot forget that ozone is a biocide, that is, it can also be harmful to humans at certain concentrations. That is why, in the event that ozone-producing articles are purchased, they must be used under strict safety measures such as
- Not to be used in the presence of people
- Applicators must have the appropriate protective equipment.
- As a hazardous chemical, it can produce adverse effects. The classification inventory of ECHA (European Chemicals Agency) reports the classification of this substance as hazardous by inhalation, skin irritation and eye damage.
- The disinfected site must be adequately ventilated before use.
- May react with flammable substances and may produce dangerous chemical reactions on contact with other chemicals.
This means that, although their use is not prohibited, the use of ozone producing machines to terminate the coronavirus is not recommended. Therefore, although it costs more work, the most effective way is still to disinfect objects and surfaces by hand with virucides whose effectiveness has been proven, such as bleach and soap. And to avoid contagion, maintain social distance, wash your hands frequently and use masks whenever recommended.