Chlorine dioxide is a gas with the chemical formula ClO2Chlorine dioxide is a highly effective, indoor climate neutral and safe means of combating microbiological contamination. Chlorine dioxide is used worldwide for the purification of drinking water and drinking water systems (both for humans and animals) and for disinfection of wastewater. It is also effective for mold and odor remediation. In various contexts, chlorine dioxide has been evaluated and approved by a number of authorities, including the US authorities EPA and FDA.
A chemical degradation of microorganisms
Chlorine dioxide is highly effective against bacteria and viruses in concentrations as low as 0.1 ppm. Not only does it effectively kill free-floating microorganisms, but it is also very effective at disinfecting surfaces with attached bacteria in the form of biofilm - a thin film of bacteria on the surface of a material.
With a minimal contact time, chlorine dioxide is used effectively against many pathogenic organisms (and their resting stages). In addition, chlorine dioxide's ability to break down biofilm means that the regrowth of microorganisms is greatly delayed and, with the continuous addition of very low concentrations, completely prevented.
Due to its mechanism of action, which consists of a chemical breakdown of the organisms' cell membrane by oxidation, there is no development of resistance to chlorine dioxide.
Highly effective for disinfection
Infection with microorganisms causes disease outbreaks in both humans and animals. In general, we have a very high degree of control over the microbiological quality of our drinking water in Denmark, so it is rare to see outbreaks of disease caused by water quality. But to maintain this high standard, preventive disinfection of containers and systems is an ongoing need. Drinking water systems in animal houses are more exposed to long standing times and low flow, where waterborne infections can be a real and troublesome problem.
Out in the world, we often see infections of Listeria, Salmonella, Shigella and E. Coli originating from food and a number of cases of infections from water installations in hotels, offices and cruise ships caused by Legionella, Noro virus, Cryptosporium etc.
Common to all of the above challenges is that chlorine dioxide can prevent the growth of microorganisms even at very low concentrations, as a continuous addition of between 0.2 and 0.8 ppm has proven highly effective after initial sterilization at a concentration of around 10 ppm. As chlorine dioxide is a gas dissolved in water, and as it is a stable solution, when disinfecting water systems, it can be transported around with the water and thus come into close contact with both the biofilm on the inside of pipes and tanks and the free-floating microorganisms. When chlorine dioxide comes into contact with microorganisms, it penetrates their cell membranes and destroys basic life processes. This penetration is different from several other oxidative products that just "scorch the surface" of everything they come into contact with.
The same process occurs when chlorine dioxide is used in mold remediation and rising sewage remediation, where a concentration of 1000 ppm and a contact time of 60 seconds is enough to ensure complete sterilization of even heavily mold infested surfaces.
An indoor climate neutral agent
The effectiveness of chlorine dioxide is due to its high reactivity. This high reactivity is also the reason why free chlorine dioxide is broken down very quickly by light. During decomposition, chlorine dioxide is converted into oxygen and sodium chloride (common kitchen salt), making it an indoor climate neutral agent.
Chlorine dioxide in Protox's work
Protox offers chlorine dioxide technology for use in the following areas:
- Mold remediation where the products ProtoxHysan and ProtoxBiox applied
- Remediation after rising sewage using ProtoxHysan and ProtoxBiox products
- Disinfection of drinking water systems for humans and animals using ProtoxBiox and ProtoxCidox products
- Disinfection of irrigation systems In nurseries where ProtoxBiox and ProtoxCidox products are used
- Odor remediation, both delivered in liquid form and as a gas-generating solid, where the products ProtoxHysan and ProtoxAbScent
Note: For odor remediation, it is not recommended to use products with chlorine dioxide on "soft" surfaces such as upholstered furniture, textiles and carpets as it has a bleaching effect. Instead, it is recommended to use Protox Odorlesswhich does not contain chlorine dioxide and is developed from a biological process with bacterial cultures and enzymes.