Polonium - History

History

Also tentatively called "Radium F", polonium was discovered by Marie and Pierre Curie in 1898 and was named after Marie Curie's native land of Poland (Latin: Polonia) Poland at the time was under Russian, Prussian, and Austrian partition, and did not exist as an independent country. It was Curie's hope that naming the element after her native land would publicize its lack of independence. Polonium may be the first element named to highlight a political controversy.

This element was the first one discovered by the Curies while they were investigating the cause of pitchblende radioactivity. The pitchblende, after removal of the radioactive elements uranium and thorium, was more radioactive than both the uranium and thorium put together. This spurred the Curies on to find additional radioactive elements. The Curies first separated out polonium from the pitchblende, and then within a few years, also isolated radium.

In the United States, Polonium was produced as part of the Manhattan Project during World War II. It was a critical part of the implosion-type nuclear weapon design used in the Fat Man bomb on Nagasaki in 1945. Polonium and Beryllium were the key ingredients of the 'Urchin' detonator at the center of the bomb's spherical Plutonium pit. The Urchin ignited the nuclear chain reaction at the moment of prompt-criticality to ensure the bomb did not fizzle.

Much of the basic physics of Polonium was classified until after the war. The fact that it was used as an initiator was classifed until the 1960s.

The Atomic Energy Commission and the Manhattan Project funded human experiments using polonium on 5 people at the University of Rochester between 1943 and 1947. The people were administered between 9 and 22 microcuries of Polonium to study its excretion.