Dr John’s research is operated in a cross-disciplinary environment that spans the width of chemical engineering, electrochemistry, environmental chemistry and environmental engineering, specializing in solid waste management, circular economy and optimization methods for recycling and recovery of valuable resources from waste, especially from the Municipal Solid Waste Stream (plastics, metals, etc.). He, also, specializes in the remediation of soils, sediments and wastewaters contaminated with toxic metals and PAHs by the use of advanced electrokinetic/electrochemical techniques. Substantial research and specific focus has also been given in the qualitative and quantitative toxicity characterization of WEEE, recovery of valuable materials from it (e.g. metals/metalloids), plastic waste and additives in them, as well as studies of environmental risk assessment in aquatic and marine Ecosystems contaminated with both organic and inorganic pollutants.