 Discovery Information
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| Who: D.R.Corson, K.R.MacKenzie, E.Segre |
| When: 1940 |
| Where: United States |
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| Name Origin
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| Greek: astatos (unstable). |
| "Astatine" in different languages. |
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| Sources
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| Does not occur in nature. Produced by bombarding bismuth with alpha particles. The longest-lived isotope, 210At, has a half-life of only 8.3 hours. There are about 20 isotopes known, all of which are radioactive. Astatine is a halogen and possibly accumulates in the thyroid like iodine.
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| Uses
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| None. |
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| History
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| first synthesized in 1940 by Dale R. Corson, K. R. MacKenzie, and Emilio Segre at the University of California, Berkeley by barraging bismuth with alpha particles.
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| An earlier name for the element was alabamine (Ab). |
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| Notes
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| With the possible exception of francium, astatine is the rarest naturally occurring element with the total amount in Earth's crust estimated to be less than 1 oz
(28 g) at any one time; this amounts to less than one teaspoon of the element. Astatine is in "The Guinness Book of Records"
as the rarest element on Earth.
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| Hazards
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| This highly radioactive element has been confirmed by mass spectrometers to behave chemically much like other halogens, especially iodine (it would probably accumulate in the thyroid gland like iodine). Astatine is thought to be more metallic than iodine.
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