Mirco Bundschuh Dec 2009
Friday 18 December 2009, 10:30 AM
Mirco Bundschuh
Institute for Environmental Sciences, University of Koblenz, Germany
Ozonation as an additional step in wastewater treatment – evidences for beneficial effects on organic matter decomposition and fitness of aquatic invertebrates
Ozone is a potent oxidant due to the formation of free radicals and therefore represents an effective agent to remove pharmaceuticals and other organic micropollutants from wastewater. The project "Strategy MicroPoll" examines the application of this technique at a municipal wastewater treatment plant near Zurich, Switzerland equipped with a full-scale ozonation. The ecotoxicological effects of ozonation were investigated in several experiments in the laboratory, in situ and field microsoms using Gammarus fossarum test organism, which is an important leaf shredding organism in European catchments. A first laboratory experiment investigated the effects of ozonation on the food choice of G. fossarum found a significant preference of the test organism for leaves conditioned in wastewater treated with 5 mg ozone/L when offered together with leaves conditioned in non-treated wastewater. In addition, the feeding activity G. fossarum was significantly higher when exposed against ozone treated wastewater compared to non-treated wastewater and was linearly related as Gammarus was exposed to different mixtures of ozone treated and non-treated wastewater. In situ experiments were conducted in the receiving stream the Futbach before and during the operation of the ozonation. Those experiments confirmed feeding activity inhibition in Gammarus exposed at downstream sites compared to upstream sites and a disappearance of the effect with the beginning of the ozonation. Finally, population sizes of G. fossarum in outdoor microcosms were also significantly reduced by approximately 60% in non-ozone treated compared to ozone treated wastewater. Potential mechanisms of ozonation that lead to an increase of food quality for invertebrates are discussed.
BIO - Mirco Bundschuh is an Environmental Scientist and in his final phase of his PhD studies at the Institute for Environmental Sciences. During the past years he was working in the field of aquatic ecotoxicology with special interest in the implications of anthropogenic stress in organic matter decomposition. He is original member of the Student Advisory Council of the Society of Environmental Toxicology & Chemistry Europe and chaired this committee for 3 years.
