Iodine-129

An isotope of iodine

Iodine-129

Iodine-129 decay chain illustration

Iodine-129 (I
₁₂₉ ) is a long-lived radioisotope of iodine. It is one of the isotopes of iodine that is of significant interest in the fields of nuclear physics, environmental science, and geology.

Properties

Iodine-129 has a half-life of approximately 15.7 million years, making it a long-lived isotope. It decays via beta decay to stable xenon-129. The long half-life of iodine-129 makes it useful for dating geological and environmental samples.

Production

Iodine-129 is produced both naturally and anthropogenically. Naturally, it is formed through the spontaneous fission of uranium and thorium in the Earth's crust. Anthropogenically, it is produced in significant quantities as a byproduct of nuclear fission in nuclear reactors and during the detonation of nuclear weapons.

Applications

Iodine-129 is used in various scientific fields due to its long half-life and unique properties:

• In geology, it is used for dating groundwater and ice cores, providing insights into the age and movement of water masses.
• In environmental science, iodine-129 is used to trace the movement of nuclear contaminants in the environment, particularly from nuclear reprocessing plants.
• In nuclear medicine, although not directly used for treatment, iodine-129's presence is monitored to understand the behavior of iodine isotopes in the human body.

Environmental Impact

The release of iodine-129 into the environment, primarily from nuclear reprocessing plants, has raised concerns due to its long half-life and mobility in the environment. It can be transported over long distances in the atmosphere and through water systems, leading to widespread distribution.

Safety and Handling

Due to its radioactivity, iodine-129 must be handled with care, following strict safety protocols to minimize exposure. It is important to monitor and control its release into the environment to prevent contamination.

Related pages

• Isotopes of iodine
• Nuclear fission
• Radioactive decay
• Environmental radioactivity