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Isotope Sciences Program

Cesium-137

cesium 137
Commercial blood irradiator (Gamma3000; Best Theratronics, Inc.). Blood irradiation inhibits lymphocyte blast transformation and represents the most effective method for preventing graft-versus-host disease associated with blood transfusions. Typical blood irradiators of this type contain 575 to 2900 curies of cesium-137. These systems provide high security against possible theft of their cesium-137 chloride sources.

We prepare and ship refined cesium-137 in customer-specified chemical forms for applications in gamma irradiators, cancer-treatment (brachytherapy) sealed sources, vehicle and cargo gamma-ray inspection systems, and counting standards.

Cesium-137 is a radioactive isotope of elemental cesium, and is produced in nuclear reactor fuel as a uranium fission product. Cesium-137 has a physical half-life of 30.2 years. Cesium-137 decays by beta-emission to its daughter product barium-137 (stable). Cesium-137 also emits a 0.662 MeV gamma ray (85%), which is important for nuclear spectrometer calibrations.

We prepare cesium-137 by recycling excess source materials as an alternative to waste disposal in shallow-land burial sites.

Isotope Sciences Program

Medical Isotopes