This project addressed the scientific and engineering developments required for a practical approach to landscape level aquatic risk assessment. It developed concepts and methodologies for aquatic risk characterization at landscape-scales with the ‘catchment’ as the focal processing and assessing unit. Looking at the catchment scale was deemed suitable since notwithstanding potential inter-catchment transfer of water chemicals and organisms the spatial dynamics of chemical inputs could be captured fully.The project had strong engineering aspects and an interdisciplinary character bridging the gap between the long-separated fields of chemical fate and exposure and the ecotoxicological and effect arena. For BCS (Bayer Crop Science) it was related to a ‘long-term initiative’ which is intended to enable dealing with future challenges of environmental risk assessment of chemicals.i The latter is expected to become a more region-specific approach and less generic. For WENR it was part of the strategic effort to develop applicable concepts to be used for landscape scale risk assessment and to adapt its (modelling) tools to be able to deal with landscape-scale risk assessment. Jointly the problem was formulated concepts were developed and refined and modeling tools and scenarios were formulated and implemented.

The current regulatory assessment for pesticides needs to become more relevant and realistic. The inclusion of landscape scale approaches that take spatial and temporal dynamics of pesticides and organisms into account is a key aspect of this improvement. In the future such an approach may be adopted to supplement higher tier regulatory assessment for pesticides in the EU.

A) Model development and parameterization. A framework was developed and presented that allows for the flexible coupling of models. Currently the framework contains a farming module that simulates farmer applications a drift model that simulates the drift deposition after application of pesticides environmental information based on a 26 year pre-run of a hydrological model a fate model simulating the fate of the pesticide in the water and sediment of the water courses in the landscape and different types of effect models that simulate the effect of pesticide exposure to a number of test-species on individual and population level.B) Scenario identification. The developed landscape scale model will be applied to a specific catchments as part of pre-defined use cases. The use case worked on was the application of a strongly sorbing insecticide to large fruit crops. This resulted in a number of presentations at international conferences discussing the approach and the outcomes of landscape scale modelling approaches in the context of environmental risk assessment.C) Defining the conceptual risk assessment framework. A draft generic framework was developed and presented at the international conference SETAC in 2021. Also the team explored options for risk communication based on the landscape scale modelling outcomes. This is work in progress and will be continued in a follow up TKI project.

This project has provided:-a landscape scale system modelling framework that explicitly incorporates spatial and temporal dynamics of both fate and effect and that allows for the coupling of different modules (such as a module that simulates farmer applications a drift module a pesticide fate module and individual based effect models and population models) in view of its use in the risk assessment. The system will be made available for other users.-a draft framework for risk assessment decisions based on an integrated approach which is to be developed further in a future project that includes other stakeholders.

The results of the project were presented at various international conferences. Also, the developed landscape scale modelling framework will be made available to other stakeholders with the final aim to advance the current ERA methodology and move towards a more integrated regional scale risk assessment. This is in the interest of the European community.

https://doi.org/10.18174/547183

Dit staat omschreven in de samenwerkingsovereenkomst.

Op de website van de TKI Deltatechnologie worden de resultaten gepubliceerd.

Op de website van de TKI Deltatechnologie worden de resultaten gepubliceerd.