In recent years, environmental concerns on the previous use of poly-fluorinated compounds (PFCs, particularly in the form of PFOS) in firefighting training sites has been a major public safety concern on the use of animal products from the fields and surrounding coastal waters, the first of which centred around Korsør Nor. Present knowledge on PFCs sources, distribution, fate, and toxicity in coastal waters is, however, limited. In addition, the latest WFD analysis of the fjords around Smålandsfarvandet and the Great belt shows non-compliance with good chemical status for 2021-2027. The non-compliance was mainly due to lead and mercury exceedances in biota in all areas, but also cadmium in Dybsø and Avnø Fjords, and brominated flame-retardants in biota and nonylphenols in sediments in Skælskør Nor. However, not all HS in the national monitoring program (NOVANA) have been measured in all areas, and the stations measured are mainly representative coastal stations, not near known pollution sources.

Despite the increasing interest of HS in the marine environment, there is still limited knowledge on the amount, origin, and toxicity of released HS. This makes it difficult to assess the impact of HS and if they pose a risk to marine life. We suggest developing a new concept where different tools are integrated to give a more holistic assessment of the status, impacts, risks, and fate of HS in coastal waters. 

Figure 2. Map of the study area (south-eastern Great Belt and Smålandsfarvandet) with the different HS point sources indicated and tentative stations. From: MiljøGIS