NIFES has been monitoring mercury levels in fish and crabs caught near the WW2 submarine U-864 on behalf of the Norwegian Coastguard since 2004. The wreck is known to contain a mercury cargo. The latest analyses of samples gathered in 2013 show no change from previous years.
“The levels that we have found in the samples from around the wreck are virtually the same as elsewhere off the west coast of Norway. This shows that seafood is scarcely affected by mercury in the sediment around the wreck,” says NIFES scientist Sylvia Frantzen.
The levels analysed in tusk caught near the wreck are in fact lower than in other western Norwegian waters, both in 2013 and in the samples as a whole. Only in crab brown meat is the level higher than what we find in western Norwegian sites and elsewhere on the coast, but even so, the levels are not high enough to compromise food safety.
The concentrations of mercury in tusk and crab are generally below the European Union’s and Norway’s maximum permitted levels for human consumption.
In 2013, two species of deep water sea-lice (amphipods Natatolana borealis and Tmetonyx cicada) were added to the mercury monitoring programme.. Large numbers of these tiny animals inhabit the area of the wreck, and they probably serve as food for both fish and crabs.
“We don’t have much data for these species at the moment, but so far, there is nothing that suggests that they are affected by mercury in the area,” says Frantzen.
According to its cargo manifest, the German U-864 submarine was carrying 60 – 70 tonnes of metallic mercury when it was sunk by a British submarine west of Fedje in February 1945. The wreck was not located until 2003, and samples of sediment from the site have revealed high concentrations of mercury.
- Fedje 2013 Hg fisk og krabbe