title: Fate and transport of polychlorinated biphenyls (PCBs) in the River Thames catchment - Insights from a coupled multimedia fate and hydrobiogeochemical transport model.
abstract: The fate of persistent organic pollutants (POPs) in riverine environments is strongly influenced by hydrology (including flooding) and fluxes of sediments and organic carbon. Coupling multimedia fate models (MMFMs) and hydrobiogeochemical transport models offers unique opportunities for understanding the environmental behaviour of POPs. While MMFMs are widely used for simulating the fate and transport of legacy and emerging pollutants, they use greatly simplified representations of climate, hydrology and biogeochemical processes. Using additional information about weather, river flows and water chemistry in hydrobiogeochemical transport models can lead to new insights about POP behaviour in rivers. As most riverine POPs are associated with suspended sediments (SS) or dissolved organic carbon (DOC), coupled models simulating SS and DOC can provide additional insights about POPs behaviour. Coupled simulations of river flow, DOC, SS and POP dynamics offer the possibility of improved predictions of contaminant fate and fluxes by leveraging the additional information in routine water quality time series. Here, we present an application of a daily time step dynamic coupled multimedia fate and hydrobiogeochemical transport model (The Integrated Catchment (INCA) Contaminants model) to simulate the behaviour of selected PCB congeners in the River Thames (UK). This is a follow-up to an earlier study where a Level III fugacity model was used to simulate PCB behaviour in the Thames. While coupled models are more complex to apply, we show that they can lead to much better representation of POPs dynamics. The present study shows the importance of accurate sediment and organic carbon simulations to successfully predict riverine PCB transport. Furthermore, it demonstrates the important impact of short-term weather variation on PCB movement through the environment. Specifically, it shows the consequences of the severe flooding, which occurred in early 2014 on sediment PCB concentrations in the River Thames.
authors.affiliation: School of Geography and the Environment, University of Oxford, South Parks Road, Oxford OX1 3QY, UK.
authors.forename: Q
authors.initials: Q
authors.lastname: Lu
authors.affiliation: Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden. Electronic address: martyn.futter@slu.se.
authors.forename: M N
authors.initials: MN
authors.lastname: Futter
authors.affiliation: Norwegian Institute for Water Research, NO-0349 Oslo, Norway; Research Centre for Toxic Compounds in the Environment, Masaryk University, 62500 Brno, Czech Republic.
authors.forename: L
authors.initials: L
authors.lastname: Nizzetto
authors.affiliation: School of Geography and the Environment, University of Oxford, South Parks Road, Oxford OX1 3QY, UK.
authors.forename: G
authors.initials: G
authors.lastname: Bussi
authors.affiliation: Centre of Ecology and Hydrology, Maclean Building, Benson Lane, Crowmarsh Gifford, Wallingford, Oxfordshire OX10 8BB, UK.
authors.forename: M D
authors.initials: MD
authors.lastname: Jürgens
authors.affiliation: School of Geography and the Environment, University of Oxford, South Parks Road, Oxford OX1 3QY, UK. Electronic address: paul.whitehead@ouce.ox.ac.uk.
authors.forename: P G
authors.initials: PG
authors.lastname: Whitehead
mesh_terms: D004739:England; D004784:Environmental Monitoring; D008962:Models, Theoretical; D011078:Polychlorinated Biphenyls / Q000032:analysis*; D045483:Rivers / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D014874:Water Pollutants, Chemical; D011078:Polychlorinated Biphenyls
keywords: INCA; PCBs; River Thames; Sediment