It is not only the Russians that have had problems with dangerous polonium

Newspaper readers this week will have  been shocked at the front page expose of details of the Russian Government's apparent murder of one of its own former spooks, Alexander Litvinenko,  by radioactive polonium poisoning ( eg "An Act of nuclear terrorism that put thousands at risk," Independent, 28 January).
They may also be shocked that in the early years of developing the predecessor to the Trident nuclear WMD, our nuclear boffins  had a terrible accident at Sellafield ( then called Windscale) when trying to produce  polonium - by irradiating bismuth oxide cartridges - in the iconic Windscale piles, resulting in the widespread polonium contamination of north west England in October 1957.
The official history of the accident, by the late Lorna Arnold,  ( published in 1992), revealed ( at page 97) that following the accident polonium pollution was detected within days in northern Europe. Samples were collected in Copenhagen, Oslo, Bonn, and The Hague and analysed by the UK Atomic Energy Authority  scientists at Harwell  near Oxford.
A paper revealing this was published, ironically considering the purpose of Sellafield in the atomic bomb programme, by Dr John Dunster, chief health physicist for UKAEA at Sellafield, at the United Nations' Peaceful Uses of Atomic Energy conference in Geneva, in 1958. Perhaps it was to smokescreen the real military nuclear materials production purposes of the Windscale piles.
So it is not only the Russians that have  had problems with dangerous polonium.