Do not trust: these are the risks of disinfecting with 'homemade' ozone

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If you are in charge of a pharmacy, a restaurant, a hairdresser, a workshop or a kindergarten, to give examples, it is possible that in the last few weeks a commercial has approached you (by mail or telephone) to tell you -and sing- benefits of the new fashionable gas. "It is 300 times more powerful than bleach!" "The biggest disinfectant according to the WHO" -say some without tousling-. The idea is to install a device with which, little more than pressing a button, the premises are easily disinfected, generating safer spaces. The prices of equipment and facilities are usually between 100 and 1000. The problem is that, when something is too beautiful to be true ... it is not usually true.

Ozone has not yet been proven effective against Sars-CoV-2

It is true that ozone is a very powerful oxidant that is used as a disinfectant. But the allusions made by some commercials to the WHO are extrapolated from a report in which they do not specifically talk about these devices but rather about the ability of ozone to disinfect water. As we know, water is not among the main routes of transmission of the coronavirus and there is no need to disinfect water beyond its usual treatment. It is important to know that, for now, this active substance has not yet been approved at a European level, so the health administration cannot provide any document under biocide legislation that establishes its efficacy or the safety of its use.

It is currently being evaluated as an active substance by Germany and the Netherlands but no draft evaluation report has yet been submitted. This means that no commercial or manufacturer can guarantee at the moment the elimination of coronavirus with ozone. If it is approved later, we will all celebrate. The more weapons we have to fight the virus, the better. But at the moment it should not be used as an advertising claim. Especially when there are other alternatives. This is specifically indicated by the EPA (United States Environmental Protection Agency). For its part, the Ministry of Health has a list of virucides of 49 pages full of products that have demonstrated their ability to eliminate viruses. Does it make sense to disinfect our business with a substance that has not yet been proven effective and that is not among the recommendations of health authorities when there are hundreds that have?

Differences between "homemade" ozone devices and companies authorized to disinfect with ozone

It is important to differentiate between the companies that try to "put" a device in your business (many of them new or reconverted, which have emerged after the Covid-19 mushrooms) and the companies that previously provided this disinfection services to third parties generated on-site ozone in establishments.

The latter must be registered in the Registry of Biocidal Establishments and Services and carry out their activity in a regulated manner (including in hospitals and operating rooms). Professional applicators carry out the process with the premises empty and using protective equipment (PPE). Upon completion, they perform a measurement to verify that ambient ozone levels are safe and take care of ventilation to avoid risks to workers or customers. Safe levels of ozone in the environment are around 0.12 ppm ozone, but disinfection requires levels up to 100 times higher.

Very different are disinfection devices that are happily being sold for business. These devices also existed before the coronavirus for other uses. They were already used in public toilets or in cars because at lower ozone concentrations they are able to eliminate bacteria responsible for bad odors. They create a pleasant atmosphere that gives a "clean" feeling.

The problem is that at low concentrations it cannot be guaranteed that the coronavirus will be eliminated and at higher concentrations its use can be dangerous, since at the "home" level the employer does not have either EPIs or adequate devices for environmental measurements. This is not to mention the "continuous flow" devices that boast of constantly emitting gas in the business. Ozone should never be applied in the presence of people and this is literally stated by the Ministry of Health in this note of April 27. A separate chapter deserves other techniques such as the tunnels or arches that nebulize ozone with which even footballers are fumigating and which, according to this same note from the Ministry of Health, "should not be applied on people in any way." Again, if concentration is safe for people, it would be something like sprinkling them with holy water.

What are the risks of ozone misuse?

The European Agency for Chemical Substances and Mixtures has classified this substance as dangerous for the respiratory route , skin irritation and eye damage. It can also react with flammable substances and produce dangerous chemical reactions when reacting with other chemicals. This is the case of compounds present in common cleaning products or air fresheners, such as D-limonene, with which ozone can associate, generating formaldehyde, a potentially carcinogenic compound if it accumulates in the environment.

Why are these devices successful if no official body recommends their use against the Covid-19?

First, cleaning everything with bleach is exhausting and unpleasant due to its strong smell. It is reasonable to try to find more comfortable solutions. Second, because it sounds more exotic compared to the competition, to say that your establishment has ozone to say that it has Lejía Conejo (which, by the way, is on the official list of virucides). The fear, also reasonable, is that if an establishment believes that ozone is eliminating the virus, thanks to that false sense of security , relax the disinfection and prevention measures that are effective.

It can't do wrong ... what if I keep bleach but buy an ozone machine "just in case"?

Leaving aside the risks of unprofessional handling of ozone, the "just in case" here is not very helpful. The virus, like the procession, goes inside. And even if ozone is shown to be effective against SARS-CoV-2 (I insist, hopefully it is) in the microsecond in which a positive person enters our establishment and leaves their exhalation droplets on the bar or counter, The magic of disinfection is broken and you have to start over. And if customers, each other, or the workers don't keep the safe distance, the ozone you've applied won't neutralize these droplets when they are exhaled. Good hygiene practices, the safety distance and the use of the mask are the most effective prevention measures in business. Hopefully, the competent authorities and organizations will get their hands on this melon because the economy of companies (especially the self-employed) is reduced enough so that fear and disinformation lead them to leave the money that many do not have in devices that they do not need.

In accordance with the criteria of The Trust Project

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