title: Influence of Different Sewer Biofilms on Transformation Rates of Drugs.
abstract: To estimate drug consumption more reliably, wastewater-based epidemiology would benefit from a better understanding of drug residue stability during in-sewer transport. We conducted batch experiments with real, fresh wastewater and sewer biofilms. Experimental conditions mimic small to medium-sized gravity sewers with a relevant ratio of biofilm surface area to wastewater volume (33 m2m-3). The influences of biological, chemical, and physical processes on the transformation of 30 illicit drug and pharmaceutical residues were quantified. Rates varied among locations and over time. Three substances were not stable-that is, >20% transformation, mainly due to biological processes-at least for one type of tested biofilm for a residence time ≤2 h: amphetamine, 6-acetylcodeine, and 6-monoacetylmorphine. Cocaine, ecgonine methyl ester, norcocaine, cocaethylene, and mephedrone were mainly transformed by chemical hydrolysis and, hence, also unstable in sewers. In contrast, ketamine, norketamine, O-desmethyltramadol, diclofenac, carbamazepine, and methoxetamine were not substantially affected by in-sewer processes under all tested conditions and residence times up to 12 h. Our transformation rates include careful quantification of uncertainty and can be used to identify situations in which specific compounds are not stable. This will improve accuracy and uncertainty estimates of drug consumption when applied to the back-calculation.
authors.affiliation: Swiss Federal Institute of Aquatic Science and Technology (Eawag) , 8600 Dübendorf, Switzerland.
authors.forename: Ann-Kathrin
authors.identifier: 0000-0002-2503-064X
authors.initials: AK
authors.lastname: McCall
authors.affiliation: Swiss Federal Institute of Aquatic Science and Technology (Eawag) , 8600 Dübendorf, Switzerland.
authors.forename: Andreas
authors.initials: A
authors.lastname: Scheidegger
authors.affiliation: Department of Forensic Pharmacology & Toxicology, Zurich Institute of Forensic Medicine, University of Zurich , 8057 Zurich, Switzerland.
authors.forename: Milena M
authors.initials: MM
authors.lastname: Madry
authors.affiliation: Department of Forensic Pharmacology & Toxicology, Zurich Institute of Forensic Medicine, University of Zurich , 8057 Zurich, Switzerland.
authors.forename: Andrea E
authors.initials: AE
authors.lastname: Steuer
authors.affiliation: Swiss Federal Institute of Aquatic Science and Technology (Eawag) , 8600 Dübendorf, Switzerland.|Institute of Environmental Engineering, ETH Zürich , 8093 Zürich, Switzerland.|Department of Biotechnology, Delft University of Technology , 2628 BC Delft, The Netherlands.|Department of Chemistry and Bioscience, Aalborg University , 9220 Aalborg, Denmark.
authors.forename: David G
authors.initials: DG
authors.lastname: Weissbrodt
authors.affiliation: ModelEAU, Département de Génie Civil et de Génie des Eaux, Université Laval , Pavillon Pouliot, 1065 av. de la Médecine, Québec City, Québec G1 V 0A6, Canada.
authors.forename: Peter A
authors.initials: PA
authors.lastname: Vanrolleghem
authors.affiliation: Department of Forensic Pharmacology & Toxicology, Zurich Institute of Forensic Medicine, University of Zurich , 8057 Zurich, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Kraemer
authors.affiliation: Swiss Federal Institute of Aquatic Science and Technology (Eawag) , 8600 Dübendorf, Switzerland.|Institute of Environmental Engineering, ETH Zürich , 8093 Zürich, Switzerland.
authors.forename: Eberhard
authors.initials: E
authors.lastname: Morgenroth
authors.affiliation: Swiss Federal Institute of Aquatic Science and Technology (Eawag) , 8600 Dübendorf, Switzerland.
authors.forename: Christoph
authors.initials: C
authors.lastname: Ort
mesh_terms: D018441:Biofilms; D004350:Drug Residues; D013287:Illicit Drugs; D012722:Sewage / Q000737:chemistry; D062065:Wastewater / Q000737:chemistry*
chemical_list: D013287:Illicit Drugs; D012722:Sewage; D062065:Wastewater