title: Toxication or detoxication? In vivo toxicity assessment of ozonation as advanced wastewater treatment with the rainbow trout.
abstract: Ozonation as advanced wastewater treatment method is an effective technique for micropollutant removal. However, the application of this method carries the inherent danger to produce toxic oxidation byproducts. For an ecotoxicological assessment conventionally treated wastewater, wastewater after ozonation and ozonated wastewater after sand filtration were evaluated in parallel at an operating treatment plant via the fish early life stage toxicity test (FELST) using rainbow trout (Oncorhynchus mykiss). The FELST revealed a considerable developmental retardation of test organisms exposed to ozonated WW. This was accompanied by a significant decrease in body weight and length compared to reference water, to the conventionally treated WW and to the ozonated water after sand filtration. Hence sand filtration obviously prevents from adverse ecotoxicological effects of ozonation. An additional test with yolk-sac larvae resulted in a significant reduction of vitellogenin levels in fish exposed to ozonated wastewater compared to fish reared in conventionally treated wastewater. This demonstrates the effective removal of estrogenic activity by ozonation. Adverse ozonation effects may have been a result of the conversion of chemicals into more toxic metabolites. However, sand filtration reduced toxication effects indicating that these oxidation byproducts are readily degradable or adsorbable. The results indicate that in any case ozonation should not be applied without subsequent post treatment appropriate for oxidation byproducts removal (e.g. sand filtration).
authors: Goethe University Frankfurt am Main, Biological Sciences Division, Department of Aquatic Ecotoxicology, Siesmayerstrasse 70, 60054 Frankfurt, Hessen, Germany. stalter@bio.uni-frankfurt.de
authors: Daniel
authors: D
authors: Stalter
authors: Axel
authors: A
authors: Magdeburg
authors: Mirco
authors: M
authors: Weil
authors: Thomas
authors: T
authors: Knacker
authors: Jörg
authors: J
authors: Oehlmann
mesh_terms: D000818:Animals; D017686:Oncorhynchus mykiss / Q000378:metabolism*; D010126:Ozone / Q000737:chemistry*; D018675:Toxicity Tests / Q000379:methods*; D014818:Vitellogenesis / Q000187:drug effects; D014819:Vitellogenins / Q000378:metabolism; D014865:Waste Disposal, Fluid / Q000379:methods*; D014873:Water Pollutants / Q000633:toxicity*
chemical_list: D014819:Vitellogenins; D014873:Water Pollutants; D010126:Ozone