Mapping of contamination problem areas in Europe’s seas using a multi-metric indicator-based assessment tool

Summary

We report identification and mapping of areas in Europe’s seas and coastal areas impacted by contaminants, i.e., areas with concentrations above internationally agreed threshold values. The study is based on (1) a state-of-the-art data set anchored in national monitoring activities, (2) internationally agreed target values and (3) an updated version of the CHASE assessment tool (originally: the HELCOM Chemical Status Assessment Tool). The spatial cover of data enabled us to classify 1,518 spatial assessment units, with 80% of the area assessed determined to be “problem areas”. We have demonstrated that it is possible to make an integrated assessment of contaminants spanning over four marine regions, and 10 marine sub-regions (sensu the EU Marine Strategy Framework Directive), including marine and coastal waters of 30 European countries. The power of combining data of different sources and contaminant categories over larger geographical scales, is potentially and in a long-term perspective the way forward for wider use of multi-metric indicator-based assessment tools supporting informed decision-making.