Quaternary ammonium compounds, also known as Quats, are widely used in cleaning and disinfection product formulations, but many of these products present health and environmental challenges. As the manufacturer of Nemesis eH2O, we believe it is difficult to imagine many disinfection applications in which Quats represent a better option than stabilised hypochlorous acid. Given the hazardous nature of these chemicals, and the potential risks to people and the environment, Nemesis eH2O offers a far superior alternative, delivering rapid disinfection of bacteria, spores, viruses (including non-enveloped) and fungi, without posing any risks to operators or the environment.
Quats are positively-charged (cationic) surfactants that can be effective against bacteria, fungi and enveloped viruses. Quats also provide detergent activity, so they are suitable for cleaning purposes, and are frequently included in the formulations of household and industrial products. They are also used in antiseptics – chlorhexidine and cetrimide, for example, are active ingredients in antiseptic cream.
The bactericidal action of Quats has been attributed to the inactivation of energy-producing enzymes, denaturation of essential cell proteins, and disruption of the cell membrane. The primary mechanism is the disruption of membranes, and Quats are generally active against enveloped viruses such as coronavirus but not against non-enveloped viruses. As lipophilic sanitisers, Quats are not very effective against single-stranded, non-enveloped RNA viruses, such as norovirus, because such viruses lack a lipid envelope to attack.
There are a number of factors that limit the application of Quats for disinfection purposes. Their activity, for example, can be adversely affected by (1) water hardness (during dilution), (2) fat-containing substances, and (3) anionic surfactants. In addition, (4) cotton and gauze may absorb the active ingredients of Quat based products and significantly reduce their effectiveness. There are also health and environmental concerns with the use of Quats. Many cleaning and disinfection products containing Quats are potentially hazardous to health, and product labels contain warnings against ingestion, or exposure to skin, eyes and the respiratory system. These products are frequently supplied in concentrated form, which presents a greater hazard and provides opportunities for mixing errors which may affect efficacy.
The health effects of Quats include a range of problems from mild skin and respiratory irritation up to severe caustic burns on skin and the gastrointestinal wall (depending on concentration). Quats have also been associated with allergies and occupational asthma, and with fertility and birth defects in laboratory mice.
The Quat disinfectants that contain hazardous substances also represent a threat to the environment and used containers should be incinerated or disposed of in an acceptable permitted waste disposal facility.
In summary, Quats provide an opportunity to formulate disinfectants to target specific pathogens in specific applications, especially where detergent action is also required – in the treatment of hard, non-porous surfaces, such as floors or walls for example. However, given the potential risks to people and the environment, Nemesis eH2O offers a far superior alternative; delivering rapid disinfection without posing any risks to people or the environment.