Radiation exposure levels in relatives of patients after radioiodine therapy

To assess whether the level of radioactivity received by relatives of patients treated with radioiodine [131I] is low enough to allow the patients leave the hospital earlier, thus reducing their hospital stay. Forty seven relatives of thyrotoxic patients and 23 relatives of thyroid cancer patients treated with 131I therapy were monitored for 7 days for radiation after discharging the patients at 30 MBq residual 131I. The doses measured in spouses and children were less than 1 mSv except for one child who received 1.46 mSv. In view of the low radiation doses received by the relatives, regulations could be made less stringent, thus reducing the hospital stay of the patients

Radioactive waste from a nuclear medicine department

Sampling of irrigation water and sludge from the sewage treatment plant at Sultan Qaboos University Hospital was undertaken to assess the level of radioactivity due to radionuclides used in the Nuclear Medicine Department. Radionuclide identification and corresponding activity were determined with a high purity germanium detector. The radionuclide, Iodine-131 with its eight day half-life, was of major concern while attempting to maintain its concentration in the irrigation water at a level commensurate with World Health Organization Guidelines for Drinking Water Quality which specifies that the annual radiation dose from drinking water should not exceed 0.1 mSv. This was difficult to achieve while adhering to a strict local policy of keeping thyroid cancer patients in hospital following treatment with up to 10 GBq of I-131. The study provided a unique opportunity to measure radioactive sewage in a well contained system and provided baseline data for subsequent management decisions