The PREVENT project aims at studying the oceanic exposome and the combined effects of different pollutants on marine organisms and ecosystems, including historical contaminants that are remaining in the ocean and important emerging contaminants that are expected to increase in the next decades.

The objective of the project is to anticipate the future evolution of the cycle of key contaminants, focusing on the examples of metals and microplastics, in the water column, how they are transferred through trophic chains and how their potential toxicity may impact marine organisms and ecosystems. To this aim, the PREVENT project relies on a pluridisciplinary consortium that includes experts in biogeochemistry, marine ecotoxicology, ecology, economy and environmental sociology. PREVENT will implement an innovative and highly collaborative scientific method combining experimentation, modelling, and observation, targeting the global ocean and focusing on overseas regions where we have access to a large database and samples. The experimental component of the project will articulate different spatial scales and combine mesocosms and life cycle exposures to in situ measurements. We will carry out original observations to improve our knowledge of essential processes affecting the pollutant cycles. For instance, the interactions between pollutants and marine particles (including nanoparticles) or their transfer to the different plankton types (pico/nano/micro phytoplankton and zooplankton), the gateway to the higher trophic level (HTL) organisms, are processes that are still poorly constrained. Moreover, we will quantify and model the transport and bioaccumulation of Hg, Li and microplastics during their transfer in the HTL trophic chains and their toxicity impact on HTL organisms. We will seek to understand and predict the propagation of different pollutants in marine ecosystems and their combined effects (cocktail effect) on the LTL (low trophic level) and HTL organisms considered in the project. For this purpose we will implement an integrated modeling approach informed by the observations acquired in the project to simulate the impacts of pollutants from their sources up to top-predatory fish. Concretely we will transform the NEMO-PISCES-APECOSM modeling platform that has initially been developed for climate change studies, to represent explicitly the pollutants in seawater, their transfer and bioaccumulation in LTLs and HTLs and their toxic impact on organisms and ecosystems. Future SSP-based scenarios taking into account climate and the influence of societal changes on the emission of pollutants will be developed and corresponding projections will be run. The scenarios of pollutant emission developed will be determined according to alternative SSP-specific energy transition options. A forum gathering key actors in the regulation of ocean pollution will be set up to contribute to the specification of our scenarios and ensure they are realistic and useful for regulation eventually. The projections run in the PREVENT framework will ultimately provide the knowledge base needed for anticipating the development of potential future regulations of pollution in the oceans.