Iodine-129: Its Occurrenice in Nature and Its Utility as a Tracer

See allHide authors and affiliations

Science  14 Sep 1962:
Vol. 137, Issue 3533, pp. 851-853
DOI: 10.1126/science.137.3533.851


Natural production rates of the 16 million-year iodine-129 from spontaneous fission and from cosmic-ray reactions are estimated to contribute a steady-state concentration of more than 10-14 gram of I129 per gram of I129 to the hydrosphere, the atmosphere, and the biosphere. These concentrations are expected to be detectable by neutron-activation analysis in natural materials that concentrate iodine. Substantial additional contributions have been made by fission-produced I129 in fallout, serving as an intrinsic tracer for natural iodine kinetics. Iodine-129 activation analysis has advantages as a tracer technique.