Thomas Knepper

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The aerobic biodegradation of nonylphenol ethoxylates (A9PEO) was kinetically investigated in a laboratory-scale bioreactor filled with riverwater, spiked at a concentration of 10 mg L(-1) nonionic surfactants. Analyses of the samples applying liquid chromatography-electrospray mass spectrometry (LC-ES-MS) after solid-phase enrichment revealed a relatively(More)
Parvibaculum lavamentivorans DS-1(T) utilized the commercial surfactant linear alkylbenzenesulfonate (LAS) (20 congeners with C(10) to C(13) side chains) as a carbon and energy source by shortening the side chain, and sulfophenylcarboxylates (SPCs) and similar compounds (e.g., alpha,beta-unsaturated SPCs [SPC-2Hs]) were excreted with quantitative recovery(More)
AIMS The aims were to test whether Parvibaculum lavamentivoransT degraded commercial linear alkylbenzenesulphonate (LAS) surfactant via omega-oxygenation and beta-oxidation to sulphophenylcarboxylates (SPCs), whether the organism was widespread and reisolable, and whether the degradative community used the 4-sulphocatechol 1,2-dioxygenase to cleave the(More)
The effluents of eight municipal wastewater treatment plants (WWTP) in Western Europe were analyzed by liquid-chromatography-mass spectrometry for the occurrence of 36 polar pollutants, comprising household and industrial chemicals, pharmaceuticals, and personal care products. In a long-term study of the effluents of three WWTP over 10 months, sulfophenyl(More)
The biodegradation of selected non-adsorbing persistent polar pollutants (P(3)) during wastewater (WW) treatment was studied by comparing a lab-scale membrane bioreactor (MBR) running in parallel to activated sludge treatment (AST). The investigated P(3) are relevant representatives or metabolites from the compound classes: pesticides, pharmaceuticals,(More)
Perfluorinated compounds (PFCs) can be detected worldwide in both, soil and water. In order to study the leaching behavior of this heterogeneous group of compounds in soil, flow-through column experiments have been conducted. Ten perfluoro carboxylates and four perfluoro sulfonates ranging from C4 to C14 in chain length, and contaminated sewage sludge, have(More)
Plastic debris is one of the most significant organic pollutants in the aquatic environment. Because of properties such as buoyancy and extreme durability, synthetic polymers are present in rivers, lakes, and oceans and accumulate in sediments all over the world. However, freshwater sediments have attracted less attention than the investigation of sediments(More)
This paper reports on a comprehensive reconnaissance of over seventy individual wastewater contaminants in the region of Western Balkan (WB; Bosnia and Herzegovina, Croatia and Serbia), including some prominent classes of emerging contaminants such as pharmaceuticals and personal care products, surfactants and their degradation products, plasticizers,(More)
The contamination of wastewater and sewage sludge has been examined for three phosphodiesterase type V inhibitors sildenafil, vardenafil and tadalafil, active agents of Viagra, Levitra and Cialis, respectively. Sensitive quantification methods based on solid-phase extraction (SPE) and pressurized liquid extraction (PLE) followed by high performance liquid(More)
The analysis and presence of clotrimazole, an antifungal agent with logK(OW) > 4, was thoroughly studied in the aquatic environment. For that reason analytical methods based on gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry were developed and validated to quantify clotrimazole with limits of quantification down to 5(More)