The age of the former living organism could be determined by comparing the ratio of carbon-12 and carbon-14 with the ratio in a living organism.
However, the result of dating is only reliable for objects that are up to 60,000 years old (Peterson).
A tellurium compound can be irradiated while bound as an oxide to an ion exchange column, and evolved I-131 then eluted into an alkaline solution.
More commonly, powdered elemental tellurium is irradiated and then I-131 separated from it by dry distillation of the iodine, which has a far higher vapor pressure.
Thus, iodine-131 is increasingly less employed in small doses in medical use (especially in children), but increasingly is used only in large and maximal treatment doses, as a way of killing targeted tissues.
This is known as "therapeutic use." Iodine-131 can be "seen" by nuclear medicine imaging techniques (i.e., gamma cameras) whenever it is given for therapeutic use, since about 10% of its energy and radiation dose is via gamma radiation.
Radioactive tracer isotopes are injected with hydraulic fracturing fluid to determine the injection profile and location of fractures created by hydraulic fracturing.
Apart from that, Iodine 131 and Iodine 125 are medical tracers use for medical diagnostic.See fission product yield for a comparison with other radioactive fission products.I-131 is also a major fission product of uranium-233, produced from thorium.Body conditions could be easily identified by both radioisotopes since they are easily transported through the lymphatic system(Peterson). Moreover, carbon 14 are used in archaeological dating. Irradiation of natural tellurium produces almost entirely I-131 as the only radionuclide with a half-life longer than hours, since most lighter isotopes of tellurium become heavier stable isotopes, or else stable iodine or xenon.