Iodine-125 is preferred for this purpose, due to better radiation penetration and shorter half-life (13 hours). I-125 is useful for Glomerular filtration rate (GFR) testing in the diagnosis or monitoring of patients with kidney disease. I-125 is used in Iodine-125 is used "therapeutically" in brachytherapy treatments of tumors. For radiotherapy ablation of tissues that absorb iodine (such as the thyroid), or that absorb an iodine-containing radiopharmaceutical, the beta-emitter iodine-131 is the preferred isotope. I is created by the electron capture decay of Xe, which is a synthetic isotope of xenon, itself created by neutron capture of the slightly radioactive Xe, which
Iodine deficiency through a functional iodine test in the form of an iodine skin test. In this test, the skin is painted with an iodine solution: if the iodine patch disappears quickly, this is taken as a sign of iodine deficiency. However, no accepted norms exist on the expected time interval for the patch to disappear, and in persons with dark skin color the disappeance of the patch may be difficult to assess. If a urine test is taken shortly after, the results may be altered due to the iodine absorbed previously in a skin test. Iodine deficiency is treated by ingestion