radium-224

chemical isotope

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July 13, 2026

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Radium-224 is a radioactive isotope of radium, a chemical element that is the heaviest of the alkaline-earth metals. Radium itself is a silvery-white metal that does not occur naturally in its pure form. Radium-224 is notable for its short half-life of 3.6 days.

When radium-224 is deposited in the body, it primarily affects bone surfaces. While it has been used in Europe to treat ankylosing spondylitis, its major toxicity is the potential to cause bone cancer. Unlike radium-226, which can affect bone marrow, radium-224's short half-life means its impact is largely confined to the bone surface.1

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poison
Local toxicities of common alpha-particle emitters
For example, radium-224, which is deposited mainly on bone surfaces, has been used in Europe to treat ankylosing spondylitis. Because of its short half-life (3.6 days), it affects only the bone surface and not the bone marrow. Its major toxicity is the production of bone cancer. Like…
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For example, radium-224, which is deposited mainly on bone surfaces, has been used in Europe to treat ankylosing spondylitis. Because of its short half-life (3.6 days), it affects only the bone surface and not the bone marrow. Its major toxicity is the production of bone cancer. Like…
Read More