Investigations on the significance of pollution from dumped ammunition in the Baltic Sea for bottom-dwelling fish species
The large amounts of dumped conventional munition, some of which are exposed on the seafloor of the Baltic Sea and are already releasing compounds such as trinitrotoluene (TNT), are a matter for concern and raise the question of whether populations of fish species present there are threatened.
The ammunition shells deposited for decades in the salt water of the Baltic Sea are subject to a steady decay, with the consequence that the explosives inside are leaking into the surrounding water. Explosives such as TNT, which are proven to be acutely toxic and genotoxic to fish. This leads to a high potential risk for organisms that get in contact with the explosive compounds, such as bottom-dwelling fish. In the course of the progressive corrosion of the ammunition shells, the effects on the stock of bottom-dwelling fish are unclear.
For this reason, the Thünen Institute of Fisheries Ecology is working in this pilot project on the first assessment of the contamination of flatfish species such as dab, plaice or flounder with TNT and its toxic degradation products. The results will be used to evaluate the possible influence of explosive compounds on the populations of bottom-dwelling fish species.
Flatfish from the vicinity of munition dumpsites and from reference areas will be studied with LC-MS for TNT and its metabolites. A special analysis method for explosives developed by the Thünen Institute is used to measure both known and unknown TNT metabolites. Sampling and analysis are carried out in cooperation and consultation with munition experts from the DAIMON project.
Results show that TNT and its metabolites as well as other explosives were detected in in bile fluids of fish (dab) caught in the vincinity of known munition dumping sites. In contrast, fish from reference sites showed low or no contamination.
Taking this together the relevant methods for a chemical monitoring of explosives in marine fish are ready.
Investigations of the edible part of fish an of other organs are not ready yet. Risc assessments will be performed after all analytical results are available.
11.2019 - 12.2027
Project funding number: Gefördert durch den Europäischen Meeres- und Fischereifonds der Europäischen Union
Project status: ongoing
Supported by the European Maritime and Fisheries Fund of the European Union