Po-210 as a Poison

• Death of a Dissident: The Poisoning of Alexander Litvinenko and the Return of the KGB by Alex Goldfarb, with Marina Litvinenko
  Simon and Schuster, 369 pp, £18.99, June 2007, ISBN 978 1 84737 081 5

The word ‘radioactive’ was first used in public on 18 July 1898, when Marie Curie and her husband, Pierre, reported to the French Academy of Sciences on the progress of their work on becquerel rays – what we would now call ionising radiation. The Curies had subjected pitchblende, a black mineral composed largely of uranium dioxide, to repeated heating, then dissolved the residue in acid. The process yielded a substance four hundred times more radioactive than uranium; they named it polonium, after Marie Curie’s country of origin. Later that year, they isolated radium.