Characterization and monitoring of persistent toxic organics in the aquatic environment

The effluent of a biological waste water treatment plant containing mainly non-eliminable polar compounds was treated using different types of elimination techniques. Precipitation/flocculation with ferric salts, adsorption onto lignite coke or powdered activated carbon (PAC) were used besides oxidative treatment steps like ozone (O₃) with or without ultraviolet (UV) radiation and hydrogen peroxide (H₂O₂) in combination with UV for elimination or degradation. Sum parameter analysis and substance-specific flow injection mass spectrometry (FIA/MS) were used for monitoring the elimination efficiency. Tandem mass spectrometry (FIA/MS/MS) was applied for identification. No elimination could be observed under all treatment steps applied, but degradation by oxidative processes led to improved biodegradability. The results of microtoxicity and daphnia magna toxicity testing after O₃/UV und H₂O₂/UV treatment differed widely.