radium-226

chemical isotope

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Last updated

July 13, 2026

Quick Summary

Radium-226 is a radioactive isotope of radium, which is the heaviest of the alkaline-earth metals. It is a silvery-white metal that does not occur naturally in its pure form. Radium-226 is part of the uranium-decay series and is continuously formed from the decay of uranium-238.1

Key facts about Radium-226:
* Atomic Number: 88
* Half-life: Approximately 1,600 years.1
* Properties: It is highly radioactive and emits alpha particles. Due to its chemical similarity to calcium, it tends to accumulate in bones, where its radiation can cause damage to bone marrow, leading to conditions like anemia and leukemia, as well as bone cancer.2
* Uses: Historically, radium was used in medicine for cancer treatment and in luminescent paints. However, due to its toxicity, these uses have largely been replaced by safer alternatives.1

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radium
Occurrence, properties, and uses
…known; their half-lives, except for radium-226 (1,600 years) and radium-228 (5.75 years), are less than a few weeks. The long-lived radium-226 is found in nature as a result of its continuous formation from uranium-238 decay. Radium thus occurs in all uranium ores, but it is more widely distributed because it…
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…known; their half-lives, except for radium-226 (1,600 years) and radium-228 (5.75 years), are less than a few weeks. The long-lived radium-226 is found in nature as a result of its continuous formation from uranium-238 decay. Radium thus occurs in all uranium ores, but it is more widely distributed because it…
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poison
Local toxicities of common alpha-particle emitters
…of its similarity to calcium, radium-226 is stored mainly in the bone, and it produces abnormal changes in the bone marrow, including anemia and leukemia, cancers of the bone, and paranasal sinuses. The next radioisotope in the uranium series is radon, radon-222. Although radon is radioactive, its toxicity is not…
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…of its similarity to calcium, radium-226 is stored mainly in the bone, and it produces abnormal changes in the bone marrow, including anemia and leukemia, cancers of the bone, and paranasal sinuses. The next radioisotope in the uranium series is radon, radon-222. Although radon is radioactive, its toxicity is not…
Read More