Po216

Po216 is a radioactive isotope of the element polonium, having an atomic number of 84 and a mass number of 216. It is a short‑lived nuclide that occurs in transient decay sequences rather than as a long‑lived constituent of materials. In nature, Po216 is produced in the decay chains associated with thorium-232, specifically through the alpha decay of radon-220 (thoron), and it can appear briefly as part of the decay progression toward lead-212.

Nuclear properties of Po216 include a composition of 84 protons and 132 neutrons. It decays primarily via alpha emission, transforming into lead-212. The half-life of Po216 is extremely short, typically measured in milliseconds to seconds, which limits its detectability outside of controlled laboratory or environmental monitoring settings. Because of its rapid decay, Po216 exists only as a fleeting intermediate in radiation studies and is not encountered as a practical source or material outside specialized contexts.

Safety and handling of Po216 reflect its nature as an alpha emitter. External exposure is generally of low hazard due to limited penetration, but internal exposure from inhalation or ingestion can pose significant radiological risk. Consequently, materials containing Po216 are managed under strict radiological controls in accordance with regulatory guidelines for short-lived alpha emitters.

See also: Polonium isotopes, Alpha decay, Radon progeny, Thorium-232 decay series.