iodine I 124
A radioactive isotope of iodine, a nonmetallic element of the halogen group, with an atomic mass of 124 and a half-life of 4.18 days with radioisotopic activity. Selectively accumulating in  thyroid tissue, iodine I 124 emits positrons that can be detected by positron emission tomography (PET), allowing localization of thyroid tissue. This radiosiotope also emits gamma rays.
| Synonym: | I-124 iodine 124 | 
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