Americium-241 ion (Am-241)

Americium-241 is a synthetic radioactive isotope and a member of the actinide series, primarily known as an alpha-particle emitter with a physical half-life of approximately 432 years [1]. It is not a natural biological component and does not serve any physiological function; instead, it is classified as a hazardous internal contaminant [1, 3]. Upon entering the human body via inhalation, ingestion, or contaminated wounds, americium-241 ions (predominantly in the trivalent state) circulate in the blood and preferentially deposit in the liver and on bone surfaces [1, 4]. The localized emission of high-energy alpha particles causes significant ionizing radiation damage to nearby cells, leading to double-strand DNA breaks and increasing the long-term risk of bone cancer (osteosarcoma), liver disease, and hematopoietic dysfunction [1, 4]. Because americium-241 is a toxicant rather than a therapeutic target, medical intervention focuses on decorporation therapy using chelating agents such as Pentetate calcium trisodium (Ca-DTPA) and Pentetate zinc trisodium (Zn-DTPA) [2]. These drugs act as chelators, sequestering the americium ions from biological ligands and facilitating their renal clearance to reduce the radiation dose to tissues [2].

Other names

241AmAmericium-241Am(III)Americium(3+)

Chelation of the metal ion to form a stable, water-soluble complex that is excreted in the urine.