Description
Non-thermal plasma represents a promising physicochemical tool for environmentally friendly and effective inactivation of biological organisms in aquatic environments. Its biological effects are primarily mediated by the generation of reactive oxygen and nitrogen species, acting either through direct plasma contact or indirectly via plasma-activated water (PAW). Among the most important stable reactive components of PAW is hydrogen peroxide (H2O2), considered a key carrier of the long-term biological effects of non-thermal plasma.
The present project focuses on the systematic investigation of the effect of hydrogen peroxide generated by non-thermal plasma on the viability of Schistosoma mansoni cercariae, the infectious larval stage of a major causative agent of schistosomiasis. Cercariae are released into aquatic environments, and their presence in surface and drinking water represents a serious public health risk, particularly in developing regions of the world.
The main objective of the project was to determine the concentration-dependent relationship between the amount of hydrogen peroxide applied to the aquatic environment and the survival rate of S. mansoni cercariae. In the experimental part, a defined concentration series of H2O2 solutions from 25 mg/l to 200 mg/l mimicking the concentrations of real PAW, was prepared. A standardized number of cercariae was introduced into these solutions under controlled laboratory conditions. During exposure, changes in motility and viability were monitored at defined time intervals, and the proportion of live and dead individuals was quantitatively evaluated.
Based on the obtained data, threshold and sublethal concentrations of hydrogen peroxide were determined and a dose–response model of its effect was established. The results of the project contributed to a deeper understanding of the mechanisms of plasma-mediated inactivation of parasitic larvae and helped to elucidating the relationship between non-thermal plasma parameters, H2O2 production, and the biological effects of PAW. The acquired knowledge may serve as a scientific basis for the development of effective and environmentally friendly methods for controlling the transmission of schistosomiasis, particularly in the context of drinking water treatment and quality control with strong potential for translation into practical applications in developing regions, including parts of Africa and Asia, where access to safe drinking water remains limited.