title: Occurrence and in-stream attenuation of wastewater-derived pharmaceuticals in Iberian rivers.
abstract: A multitude of pharmaceuticals enter surface waters via discharges of wastewater treatment plants (WWTPs), and many raise environmental and health concerns. Chemical fate models predict their concentrations using estimates of mass loading, dilution and in-stream attenuation. However, current comprehension of the attenuation rates remains a limiting factor for predictive models. We assessed in-stream attenuation of 75 pharmaceuticals in 4 river segments, aiming to characterize in-stream attenuation variability among different pharmaceutical compounds, as well as among river segments differing in environmental conditions. Our study revealed that in-stream attenuation was highly variable among pharmaceuticals and river segments and that none of the considered pharmaceutical physicochemical and molecular properties proved to be relevant in determining the mean attenuation rates. Instead, the octanol-water partition coefficient (Kow) influenced the variability of rates among river segments, likely due to its effect on sorption to sediments and suspended particles, and therefore influencing the balance between the different attenuation mechanisms (biotransformation, photolysis, sorption, and volatilization). The magnitude of the measured attenuation rates urges scientists to consider them as important as dilution when aiming to predict concentrations in freshwater ecosystems.
authors.affiliation: Catalan Institute for Water Research (ICRA), Carrer Emili Grahit 101, 17003 Girona, Spain. Electronic address: vicenc.acuna@icra.cat.
authors.forename: Vicenç
authors.initials: V
authors.lastname: Acuña
authors.affiliation: Catalan Institute for Water Research (ICRA), Carrer Emili Grahit 101, 17003 Girona, Spain. Electronic address: dvonschiller@icra.cat.
authors.forename: Daniel
authors.initials: D
authors.lastname: von Schiller
authors.affiliation: Catalan Institute for Water Research (ICRA), Carrer Emili Grahit 101, 17003 Girona, Spain. Electronic address: mjgarcia@icra.cat.
authors.forename: Maria Jesús
authors.initials: MJ
authors.lastname: García-Galán
authors.affiliation: Catalan Institute for Water Research (ICRA), Carrer Emili Grahit 101, 17003 Girona, Spain. Electronic address: srodriguez@icra.cat.
authors.forename: Sara
authors.initials: S
authors.lastname: Rodríguez-Mozaz
authors.affiliation: Catalan Institute for Water Research (ICRA), Carrer Emili Grahit 101, 17003 Girona, Spain. Electronic address: lcorominas@icra.cat.
authors.forename: Lluís
authors.initials: L
authors.lastname: Corominas
authors.affiliation: Catalan Institute for Water Research (ICRA), Carrer Emili Grahit 101, 17003 Girona, Spain; ICREA, Passeig Lluís Companys 23, 08010 Barcelona, Spain. Electronic address: mpetrovic@icra.cat.
authors.forename: Mira
authors.initials: M
authors.lastname: Petrovic
authors.affiliation: Catalan Institute for Water Research (ICRA), Carrer Emili Grahit 101, 17003 Girona, Spain; Laboratory of Chemical and Environmental Engineering, University of Girona, Campus Montilivi, 17071 Girona, Spain. Electronic address: manuel.poch@udg.edu.
authors.forename: Manel
authors.initials: M
authors.lastname: Poch
authors.affiliation: Catalan Institute for Water Research (ICRA), Carrer Emili Grahit 101, 17003 Girona, Spain; Water and Soil Quality Research Group, Department of Environmental Chemistry (IDAEA-CSIC), Carrer Jordi Girona 18-26, 08034 Barcelona, Spain. Electronic address: dbarcelo@icra.cat.
authors.forename: Damià
authors.initials: D
authors.lastname: Barceló
authors.affiliation: Catalan Institute for Water Research (ICRA), Carrer Emili Grahit 101, 17003 Girona, Spain; Institute of Aquatic Ecology, University of Girona, Campus Montilivi, 17071 Girona, Spain. Electronic address: ssabater@icra.cat.
authors.forename: Sergi
authors.initials: S
authors.lastname: Sabater
mesh_terms: D001711:Biotransformation; D004784:Environmental Monitoring; D008956:Models, Chemical; D004364:Pharmaceutical Preparations / Q000032:analysis*; D010782:Photolysis; D045483:Rivers / Q000737:chemistry*; D013030:Spain; D062065:Wastewater / Q000032:analysis / Q000737:chemistry* / Q000706:statistics & numerical data; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D004364:Pharmaceutical Preparations; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Ecosystem services; Natural contaminant attenuation; Pharmaceuticals; Stream ecology; Water purification; Water quality