Recommendations from a French-Swiss expert panel for improving the assessment of sediment ecotoxicological quality through the study of benthic communities

Abstract

The sediment compartment, which supports high taxonomic and functional biodiversity levels, is an essential ecological component of aquatic environments. Sediments are also an important sink for a variety of contaminants that settle and accumulate over time. European and Swiss regulations dealing with the evaluation and management of aquatic ecosystems quality do not take enough into account sediments and associated benthic communities. This is due, at least partly, to the lack of recommendations and methods to in situ evaluate the ecotoxicological impact of chemical substances which accumulate in sediments on associated benthic communities and the resulting ecological risk. Accordingly, a meeting was organized in 2017 to bring together a French-Swiss consortium, composed of scientists, environmental managers and stakeholders as well as economic players (start-ups and consultancies). The objectives of this meeting were to formulate recommendations to better characterize i) the contamination of sediments and exposure level of benthic communities, as well as (ii) resulting effects on these benthic communities to better take them into account in the evaluation and management of aquatic ecosystems quality.