PMID- 35988331 OWN - NLM STAT- MEDLINE DCOM- 20220919 LR - 20220919 IS - 1879-2448 (Electronic) IS - 0043-1354 (Linking) VI - 223 DP - 2022 Sep 1 TI - A decade of monitoring micropollutants in urban wet-weather flows: What did we learn? PG - 118968 LID - S0043-1354(22)00915-0 [pii] LID - 10.1016/j.watres.2022.118968 [doi] AB - Urban wet-weather discharges from combined sewer overflows (CSO) and stormwater outlets (SWO) are a potential pathway for micropollutants (trace contaminants) to surface waters, posing a threat to the environment and possible water reuse applications. Despite large efforts to monitor micropollutants in the last decade, the gained information is still limited and scattered. In a metastudy we performed a data-driven analysis of measurements collected at 77 sites (683 events, 297 detected micropollutants) over the last decade to investigate which micropollutants are most relevant in terms of 1) occurrence and 2) potential risk for the aquatic environment, 3) estimate the minimum number of data to be collected in monitoring studies to reliably obtain concentration estimates, and 4) provide recommendations for future monitoring campaigns. We highlight micropollutants to be prioritized due to their high occurrence and critical concentration levels compared to environmental quality standards. These top-listed micropollutants include contaminants from all chemical classes (pesticides, heavy metals, polycyclic aromatic hydrocarbons, personal care products, pharmaceuticals, and industrial and household chemicals). Analysis of over 30,000 event mean concentrations shows a large fraction of measurements (> 50%) were below the limit of quantification, stressing the need for reliable, standard monitoring procedures. High variability was observed among events and sites, with differences between micropollutant classes. The number of events required for a reliable estimate of site mean concentrations (error bandwidth of 1 around the "true" value) depends on the individual micropollutant. The median minimum number of events is 7 for CSO (2 to 31, 80%-interquantile) and 6 for SWO (1 to 25 events, 80%-interquantile). Our analysis indicates the minimum number of sites needed to assess global pollution levels and our data collection and analysis can be used to estimate the required number of sites for an urban catchment. Our data-driven analysis demonstrates how future wet-weather monitoring programs will be more effective if the consequences of high variability inherent in urban wet-weather discharges are considered. CI - Copyright (c) 2022. Published by Elsevier Ltd. FAU - Mutzner, Lena AU - Mutzner L AD - Department of Environmental and Resource Engineering (DTU Sustain), Technical University of Denmark, Bygningstorvet, Building 115, 2800 Kgs., Lyngby, Denmark. Electronic address: lezomu@dtu.dk. FAU - Furrer, Viviane AU - Furrer V AD - Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dubendorf 8600, Switzerland; Institute of Civil, Environmental and Geomatic Engineering, ETH Zurich, Zurich 8093, Switzerland. Electronic address: Viviane.Furrer@eawag.ch. FAU - Castebrunet, Helene AU - Castebrunet H AD - University of Lyon, INSA Lyon, DEEP, EA 7429, 11 rue de la Physique, Villeurbanne Cedex F-69621, France. Electronic address: hcastebrunet@gmail.com. FAU - Dittmer, Ulrich AU - Dittmer U AD - Department of Civil Engineering, Institute for Urban Water Management, Technical University Kaiserslautern, Kaiserslautern 67663, Germany. Electronic address: ulrich.dittmer@bauing.uni-kl.de. FAU - Fuchs, Stephan AU - Fuchs S AD - Department of Aquatic Environmental Engineering, Institute for Water and River Basin Management, Karlsruhe Institute of Technology (KIT), Gotthard-Franz-Str. 3, Karlsruhe 76131, Germany. Electronic address: stephan.fuchs@kit.edu. FAU - Gernjak, Wolfgang AU - Gernjak W AD - ICRA, Catalan Institute for Water Research, Scientific and Technological Park of the University of Girona, H2O Building, Emili Grahit 101, Girona 17003, Spain; ICREA, Catalan Institute for Research and Advanced Studies, Barcelona 08010, Spain. Electronic address: wgernjak@icra.cat. FAU - Gromaire, Marie-Christine AU - Gromaire MC AD - Leesu, Ecole des Ponts ParisTech, Universite Paris-Est Creteil. 6-8 avenue Blaise Pascal, Cite Descartes, Marne-la-Vallee cedex 2, 77455, France. Electronic address: marie-christine.gromaire@enpc.fr. FAU - Matzinger, Andreas AU - Matzinger A AD - Kompetenzzentrum Wasser Berlin (KWB), Berlin 10961, Germany. Electronic address: Andreas.Matzinger@kompetenz-wasser.de. FAU - Mikkelsen, Peter Steen AU - Mikkelsen PS AD - Department of Environmental and Resource Engineering (DTU Sustain), Technical University of Denmark, Bygningstorvet, Building 115, 2800 Kgs., Lyngby, Denmark. Electronic address: psmi@dtu.dk. FAU - Selbig, William R AU - Selbig WR AD - U.S. Geological Survey, Upper Midwest Water Science Center, Madison 53726, WI, United States. Electronic address: wrselbig@usgs.gov. FAU - Vezzaro, Luca AU - Vezzaro L AD - Department of Environmental and Resource Engineering (DTU Sustain), Technical University of Denmark, Bygningstorvet, Building 115, 2800 Kgs., Lyngby, Denmark. Electronic address: luve@dtu.dk. LA - eng PT - Journal Article DEP - 20220809 PL - England TA - Water Res JT - Water research JID - 0105072 RN - 0 (Metals, Heavy) RN - 0 (Pesticides) RN - 0 (Pharmaceutical Preparations) RN - 0 (Polycyclic Aromatic Hydrocarbons) RN - 0 (Water Pollutants, Chemical) RN - 059QF0KO0R (Water) SB - IM MH - Environmental Monitoring MH - *Metals, Heavy/analysis MH - *Pesticides/analysis MH - Pharmaceutical Preparations MH - *Polycyclic Aromatic Hydrocarbons/analysis MH - Rain MH - Water/analysis MH - *Water Pollutants, Chemical/analysis MH - Weather OTO - NOTNLM OT - Combined sewer overflow OT - Data-driven analysis OT - Heavy metals OT - Metastudy OT - Sampling OT - Stormwater outlets OT - Trace contaminants COIS- Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. EDAT- 2022/08/22 06:00 MHDA- 2022/09/20 06:00 CRDT- 2022/08/21 18:18 PHST- 2022/04/18 00:00 [received] PHST- 2022/07/27 00:00 [revised] PHST- 2022/08/07 00:00 [accepted] PHST- 2022/08/22 06:00 [pubmed] PHST- 2022/09/20 06:00 [medline] PHST- 2022/08/21 18:18 [entrez] AID - S0043-1354(22)00915-0 [pii] AID - 10.1016/j.watres.2022.118968 [doi] PST - ppublish SO - Water Res. 2022 Sep 1;223:118968. doi: 10.1016/j.watres.2022.118968. Epub 2022 Aug 9.