Polybrominated Dyphenyl Ethers (PBDEs) Fate and Transport in an Estuary Using a Three-dimensional Hydrodynamic Modelling Approach

The fate and transport of contaminants in estuaries is still not completely understood due to the extremely high physico-chemical variability in these environments. In this report, a 3D hydrodynamic model has been applied for estuary modelling to predict tidal flows, salinity and temperature distributions; and for the fate and transport of Polybrominated Dyphenyl Ethers (PBDEs). With this goal in mind, a hypothetical estuary system was constructed that consisted of a reach with a length of 26 km. Consequently, the hydrology of this estuary system was described primarily by the tides and the freshwater influx. The contaminant PBDE-100 was assumed to enter by means of river transport, exchange with sediments and atmospheric inputs. Two simulations were undertaken, namely one of three days and the other of one year, in order to observe how and if the model realistically had simulated the fate transport of PBDE-100 in the hypothetical estuary system. The simulations performed have shown that the model is able to represent adequately the hydrodynamic aspects as well as the typical temperature and salinity distributions. Concerning the contaminant distribution the model shows the importance of atmospheric processes as well as the role of sediments as, in this case, a source of contaminant. The next step will consist on applying this model to a real estuary and validate it with experimental data.
JRC.H.5-Rural, water and ecosystem resources