The chemical element of atomic number 85, a radioactive member of the halogen group. Astatine was first produced by bombarding bismuth with alpha particles, and it occurs in traces in nature as a decay product.‘The halogens are a group of chemical elements that includes fluorine, chlorine, bromine, iodine, and astatine.’
- ‘There is evidence that astatine behaves like iodine in the body.’
- ‘By one estimate, no more than a millionth of a gram of astatine has ever been produced in the lab.’
- ‘The total amount of astatine present in the earth's crust, however, is probably less than 1 oz.’
- ‘The bismuth target is cooled during irradiation to prevent the volatile astatine disappearing.’
- ‘This, together with its short lifetime, leaves no reason for considering the effects of astatine on human health.’
- ‘However, astatine also shows similarities to polonium and bismuth.’
1940s from Greek astatos ‘unstable’ + -ine.