The long saga of U-864 [which sank in 1945 containing 65 tons of mercury] is far from over. Many of the canisters containing the liquid mercury are now corroding. Small amounts have seeped out, and Norwegian government tests around the wreck have detected slightly raised amounts of the metal in crabs and fish — the country’s second biggest export, after oil and gas.

Indeed, Kristian Hall, an environmental consultant with a Norwegian engineering firm, said the corroding canisters could produce a threat comparable to the disaster at Minamata, Japan, where some 27 tons of industrial mercury compounds were released into a bay between 1932 and 1968, causing nerve and brain damage to hundreds of townspeople whose diet consisted in large part of local seafood.