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cesium-137 (137Cs)

a radioactive material with a half-life of 30.2 years that is used in radiotherapy as a sealed source of gamma rays intended for application to various malignancies that are treated by brachytherapy. Cesium has replaced radium for such applications. See also brachytherapy.


a chemical element, atomic number 55, atomic weight 132.905, symbol Cs. See Table 6.

a product of atomic fission by explosion or breakdown of a reactor. It is feared as a pollutant because of its very long half-life.
References in periodicals archive ?
Prior to Fukushima, however, the levels of cesium-137 off the coast of Japan, as cataloged by Michio Aoyama at the Meteorological Research Institute in Japan and others, were among the world's lowest, at around 2 becquerels per cubic meter (1 becquerel, or Bq, equals one radioactive decay event per second).
Forests and fields were subjected to a dense cloud of radioactive dust that included cesium-137, strontium-90, multiple isotopes of plutonium, and more than a dozen other radionuclides.
Cesium-137 is water-soluble and extremely toxic in minute amounts.
Analyzing plankton and fish sampled on the cruise, they consistently found cesium-134 and cesium-137.
GyRESUN (CyHAN)- Gendarmerie forces seized two glass tubes containing Cesium-137, a radioactive isotope of cesium which can be used in nuclear weapon production, in the northern province of Giresun on Tuesday.
According to a report published Monday in the journal Proceedings of the National Academy of Sciences, scientists found a tenfold increase in concentrations of radioactive cesium-134 and cesium-137 in 15 bluefin tuna samples collected from San Diego fishermen as compared to samples taken in 2008.
Historically most facilities have been using cesium-137 or sodium-22 standards for Ga-68 and F-18 calibration.
Elements that appeared to cause the greatest contamination are the isotopes of iodine and strontium although barium-140 and cesium-137 also contribute to the peril.
Cesium-137 also accumulates in tissues as it moves up the food chain, and human exposure may result in detrimental health effects or genetic mutations that can lead to cancers, according to the U.
Among the materials found below ground and in the outdoor loading area were cesium-137, thorium and uranium.
More than two-thirds of the total fallout was comprised of the long-lived radionuclides strontium-90 and cesium-137.
This means a GammaTect[TM] sensor will detect a dirty bomb made with 60 curies of Cesium-137 at a distance of 83.