Explosives from a WWII shipwreck that have been leaking for 80 years show how they can alter ocean ecosystems.

 

We at IFLScience enjoy a good shipwreck, but despite the fact that these sunken ships can serve as artificial reefs for a variety of marine species (they were crazy about Shackleton's Endurance), recent studies have revealed the harm they can do to the ecosystem. A German wreckage from World War II (WWII) that has lain on the ocean floor for 80 years has been spewing pollutants and releasing dangerous heavy metals throughout that time.

The V-1302 John Mahn ship, which went down in the Belgian portion of the North Sea, is the wreck. It was originally a German fishing trawler, but it was later reassigned to duty as a patrol boat during World War II, at which point it was attacked and sunk by the British Royal Airforce in 1942.

It is estimated that the total amount of petroleum products found in WWI and WWII shipwrecks worldwide is between 2.5 million and 20.4 million tons, proving that although they may be mysterious, they are also rife with pollution.

Scientists collected soil samples from the ship and the nearby sea floor to determine how these contaminants may be affecting the environment. A number of harmful contaminants, such as heavy metals (such as nickel and copper), polycyclic aromatic hydrocarbons (chemicals present in coal, crude oil, and gasoline), arsenic, and explosive compounds were determined to have escaped from the wreckage into the environment.

In a release, main author and PhD candidate Josefien van Landuyt of Ghent University said, "We wanted to explore if old shipwrecks in our part of the sea (Belgium) were still creating the local microbial communities and if they were still affecting the surrounding sediment." "This project's only instance of this microbiological analysis."

The results of that microbial investigation showed that the leaky shipwreck was not only modifying the contaminants in its immediate proximity but also the microbiome of the seabed. The reason for this is that the most polluted places have larger concentrations of some weird bacteria that are hot for polycyclic aromatic hydrocarbons (such Rhodobacteraceae and Chromatiaceae).

Desulfobulbia and other sulfate-reducing bacteria were living it up on the shipwreck's hull and causing corrosion there.

"We should not forget that they can be dangerous, human-made objects which were unintentionally introduced into a natural environment," van Landuyt said. "While wrecks can function as artificial reefs and have tremendous human story-telling value. "New shipwrecks are currently being excavated for this very reason.

Because of their historical significance, shipwrecks are frequently of interest to the general population, yet their potential environmental effects are frequently disregarded.

Maybe it's time we switched to a ghost story that is less harmful to the environment.