Radioactive iodine (I-131) can be used in medical therapies as a treatment and a diagnostic tool. It is most commonly used in the treatment of hyperthyroidism due to Graves’ disease or a nodule ...

Iodine-131: Used to treat thyroid gland (in the neck). ... This means that the beta-decay emissions can be monitored and the data used to calculate how long it has been since the material was alive.