REPOSITORY > RESULTS

Abstract

Access to clean water is a key requirement for a good quality of life. However, due to climate change, population growth and lack of proper water treatment, the availability of clean water is in constant decline. Among the many waterborne contaminants, viruses present an increasing concern. Human waterborne viruses infect millions of people each year, thus posing a high health risk, while plant waterborne viruses can inflict severe damage to crops, leading to food shortages and financial losses. Therefore, due to the hazardous nature of these viruses, it is crucial to inactivate them.
Cold atmospheric plasma (CAP) is emerging as a novel environmentally friendly method that can surpass the limitations of other water treatment methods to ensure sufficient virus inactivation. CAP is generally used for decontamination due to its antimicrobial properties, such as reactive oxygen and nitrogen species and ultraviolet radiation.
Virus inactivation with CAP is a relatively new field, with many promising results. However, water decontamination with CAP for the purpose of virus inactivation has yet to be explored. Therefore, the main aim of this thesis was to evaluate CAP as a water treatment method, with a focus on virus inactivation. We used three viruses as model microorganisms: two important plant pathogens, potato virus Y and pepper mild mottle virus (PMMoV), and the bacteriophage MS2. Both PMMoV and MS2 are very stable and resistant viruses that can be used as surrogates of enteric viruses for water decontamination processes. We treated water samples that contained each of these viruses and accomplished their inactivation within minutes, regardless of the virus used. The mechanisms of virus inactivation were also examined, which showed that CAP can affect both viral proteins and their nucleic acids by oxidation with reactive oxygen species. As CAP is a complex mixture rich in reactive species, the potential cytotoxic or genotoxic properties of CAP-treated water were also investigated. No toxic products were formed under the experimental conditions used.
CAP has potent antiviral properties that can successfully inactivate even the most persistent waterborne viruses without producing toxic by-products. Therefore, it represents an alternative tool for water decontamination that can help reduce the occurrence of infections in humans and plants, and consequently prevent the development of food shortages, high financial losses, hospitalization and death. The need for such a tool for virus inactivation has been further confirmed by the COVID-19 pandemic, which has highlighted the lack of methods that can effectively stop virus transmission.