Sweden will soon keep used uranium in new oxygen-free copper canisters with a life-span guaranteed at 100,000 years.

Peter Nygards, chief executive at the Swedish nuclear waste and fuel handling facility SKB, said: “We chose it because it is the best material against corrosion.” The copper has been in use for 15-20 years, and will be made into containers 50mm thick and 5m long. The uranium will be placed into steel inserts inside the canisters.