This Europe: Man's poisons are meat for 'super bacteria'

Bacteria living in the depths of the Baltic Sea off Sweden have developed an unlikely taste for what should be the world's most toxic substance. They can consume mustard gas, leaking from old German weapons dumped in the sea by the Soviet Union and Britain in 1945.

Bacteria living in the depths of the Baltic Sea off Sweden have developed an unlikely taste for what should be the world's most toxic substance. They can consume mustard gas, leaking from old German weapons dumped in the sea by the Soviet Union and Britain in 1945.

The new super-strong bacteria have been discovered at the bottom of the Bornholm Deep, one of the sites in the Baltic where some 35,000 tons of chemical weapons, manufactured but never used by the Nazis, were deposited at the end of the Second World War.

Nobody quite knows the condition of the old munitions, which include artillery shells filled with mustard gas, bombs, mines and grenades. So far there have been no serious ecological changes in the Baltic, but scientists say there has been a sinister increase in the level of phosphorus and acidity at some dump sites.

Unfortunately, the location of many of the dumps is still unknown. Aside from the Bornholm Deep, two other places where the Nazis' vast chemical weapons arsenal is known to have been deposited are the Gotland Deep, off Lithuania and Latvia, and the Little Belt, off the coast of Germany and Denmark.

Soviet and British methods of weapons disposal differed markedly. Soviet forces simply threw the munitions over the side of a ship, so they scattered across the sea floor. The British sank the weapons on board single ships, sealing them off for many years but carrying the danger that if the vessel disintegrates for any reason then many chemical weapons will be released simultaneously.

Not all the weapons are in the deepest parts of the Baltic, and sometimes mines lying in shallow waters snag the nets of fishermen. Several Danish and German fishermen are reported to have been injured by poison gas. In the Russian enclave of Kaliningrad, Russia's Oceanography Institute organised six expeditions to find the dumps but has had to stop because of a shortage of funds.