title: European environmental scenarios of chemical bioavailability in freshwater systems.
abstract: In exposure prediction for environmental risk assessment, the transition to more dynamic and realistic modelling approaches and scenarios has been recently identified as a major challenge, since it would allow a more accurate prediction of bioavailable concentrations and their variations in space and time. In this work, an improved version of the multimedia model ChimERA fate, including a phytoplankton compartment and equations to calculate phytoplankton, detritus and dissolved organic matter variations in time, was developed. The model was parameterized to simulate five dynamic scenarios for shallow meso-eutrophic water bodies based on a latitudinal gradient (in Europe); such scenarios include seasonal profiles of water temperature, phytoplankton biomass, detritus, and dissolved organic matter. Model runs were performed for each scenario for 8 hydrophobic chemicals (PCB congeners), with the aim of investigating the influence of scenario characteristics and compound properties on bioavailable concentrations. The key processes were adsorption/uptake by phytoplankton and deposition to sediment of detritus-bound chemicals. The northern scenarios ("Scandinavia" and "UK") showed the highest bioavailable concentrations, with annual maximum/minimum concentration up to 25; in contrast, for example, maximum concentrations in the "Mediterranean" scenario were lower by a factor of 2 to 9 with respect to the northern ones (depending on chemical hydrophobicity), due to the generally higher biomass and carbon levels, and showed only limited seasonal variability (up to a factor of 4). These results highlight the importance of including biomass and organic carbon dynamics in both modelling approaches and scenarios for the evaluation of exposure concentrations in aquatic environments.
authors.affiliation: Department of Science and High Technology, University of Insubria, Via Valleggio 11, 22100 Como, CO, Italy. Electronic address: antonio.diguardo@uninsubria.it.
authors.forename: Antonio
authors.initials: A
authors.lastname: Di Guardo
authors.affiliation: Department of Science and High Technology, University of Insubria, Via Valleggio 11, 22100 Como, CO, Italy.
authors.forename: Melissa
authors.initials: M
authors.lastname: Morselli
authors.affiliation: National Research Council, Institute for Ecosystem Study, Largo Tonolli 50, 28922 Verbania-Pallanza, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Morabito
authors.affiliation: Dipartimento di Matematica, Università degli Studi di Torino, Via C. Alberto 10, 10123 Torino, TO, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Semplice
authors.affiliation: Wageningen Environmental Research (Alterra), P.O. Box 47, 6700 AA Wageningen, The Netherlands; Department of Aquatic Ecology and Water Quality Management, Wageningen University, 6700 AA Wageningen, The Netherlands.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Van den Brink
authors.affiliation: University of Namur, Research Unit in Environmental and Evolutionary Ecology, Rue de Bruxelles 61, 5000 Namur, Belgium.
authors.forename: Frederik
authors.initials: F
authors.lastname: De Laender
mesh_terms: D001682:Biological Availability; D005060:Europe; D005618:Fresh Water / Q000032:analysis*; D008956:Models, Chemical; D010839:Phytoplankton; D018570:Risk Assessment; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D014874:Water Pollutants, Chemical
keywords: Detritus; Exposure assessment; Fate model; Organic chemical; Phytoplankton biomass; Pond