Sunhild Kleingärtner in conversation with Dieter Kassel

Wartime Legacy Research: Across Water in a Global Cycle. (photo alliance / Carmen Jaspersen)

The warships that sank in the North Sea still harbor ammunition. Corrosion releases toxins on which a research project has been studying since 2018. The subject is now clearly illustrated by a traveling exhibition.

There is no official figure, but scientists estimate that around 680 military wrecks from WWI and WWII lie on the bottom of the North Sea. They still house ammunition from which toxic substances escape. An international research project examines the resulting dangers.

Tour through five countries

Now there is also a traveling exhibition called “Toxic Legacies of War: North Sea Wrecks”, which aims to raise awareness of the subject and make it known to the public. It is currently on display in Bremerhaven on the grounds of the German Maritime Museum.

After debuting there, the mobile show will tour Germany, Denmark, the Netherlands, Norway and Belgium until September 2022. It is planned to stop at festivals and events focused on marine research and marine protection.

Seashells as a marker

It is estimated that there are around 1.3 million tonnes of WWII ammunition in the German North Sea alone, often in sunken warships. This is mainly TNT, explains Sunhild Kleingärtner, managing director of the German Maritime Museum and responsible for the “North Sea Wrecks” project. Any poison that escapes there enters a global cycle via water.

According to Kleingärtner, historical documents can be used to relatively well reconstruct where the ships sank. Army records were very accurate, she reports. However, identifying wrecks is not always easy.

Submerged ships are examined using molds, among others. Kleingärtner reports that these are well suited as markers. Bags of mussels are attached to the wrecks and then remain underwater for a while. The mussels then absorb toxic substances from the surrounding area and can then be examined in the laboratory.

The research project, funded with millions of euros by the EU, has been underway since 2018. The inhabitants of the North Sea want to use a database to identify, map and assess the location of wrecks, cargoes and litter on the seabed.

Samples from a wreck off Helgoland

Nine project partners from five countries are involved, including the Alfred Wegener Institute in Bremerhaven and the Schleswig-Holstein University Medical Center in Kiel with its Institute of Toxicology and Pharmacology.

More recently, scientists left in April on the German research vessel “Heincke” to take samples from the wreckage of the cruiser “SMS Mainz” west of Helgoland, which sank there during the First World War. Among other things, organisms were collected from the outer wall of the wreckage and water and sediment samples were taken.

(ahe / epd)