Das Projekt "The fate of 14C-radiolabelled diclofenac and its main human metabolite 4'-hydroxydiclofenac in membrane bioreactor treatment of wastewater" wird/wurde gefördert durch: Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung. Es wird/wurde ausgeführt durch: Fachhochschule Nordwestschweiz, Hochschule für Life Sciences, Institut für Ecopreneurship.Project aim This project aims at elucidating the fate of diclofenac, a widely consumed non-steroidal anti-inflammatory compound, during wastewater treatment. The research will identify metabolic pathways as well as degradation products and the impact of operational parameters and common treatment steps thereon. Context and impact Residues of pharmaceutically active substances in the aquatic environment pose an emerging challenge to water and wastewater treatment today. To date, more than 100 different substances could be detected in surface and ground water at various concentrations. Some of them, including diclofenac (DF), have also been detected in tap water. This is an evidence for their poor removal or incomplete degradation during wastewater treatment or drinking water production. DF has been detected in wastewater at concentrations of up to 1.9 myg/L in Switzerland with concentrations reaching up to 150 ng/L in Swiss rivers. Hydroxylated metabolites from human origin are also detected in sewage and surface water. Advanced wastewater treatment options such as membrane bioreactors (MBRs), combining activated sludge treatment with solids removal by membrane filtration, are currently considered to upgrade the removal performance of municipal and industrial plants with respect to bulk organics and nutrients removal. Their potential for trace organics elimination is related to the degradation capacities of the microbial community which may vary with different operation conditions. The project findings improve knowledge on how MBR technology can be adopted and operated to better perform with respect to the removal of diclofenac. Methodolgy and approach To increase the understanding of the fate of DF and the main human DF metabolite 4'-hydroxydiclofenac (4'-OH-DF) a lab-scale membrane bioreactors (MBRs) will be operated. The system runs with an acclimated biomass which has been exposed to diclofenac over a long period of at least six months. C-labelled 4'-OH-DF will be implemented to detect and analyze the residues of DF and 4'-OH-DF in the various fractions (e.g. sludge, permeate, exhaust gas) of laboratory scale MBRs. Elimination rates, (bio)transformation products, and radioactivity balances will be determined in MBRs. This project will also study the impact of operation conditions on the fate of both substances, as well as possible interconversion phenomena.14C-labelled DF and 14The identification of (bio)transformation products will be performed to tentatively characterize the underlying microbial processes. A radiotracer approach utilising