Estimation of radiation dose of emergency exposure during the hospitalized 131I therapy patient

Background:  The aim of the study was to estimate the radiation dose during emergency exposure to patients treated with iodine-131 during the isolation period. Materials and Methods: The dose rate from a sample of 192 patients administrated by three different radioactivity of 131I (3.7, 5.55 and 7.4 GBq) was measured, at 1 meter after 1, 24 and 48 hours post dose administration, at three different levels from the patient body (thyroid glands, abdomen and knee). The average of decay curve of the measured radiation dose rate was plotted and their values were fitted. The medical emergency exposure was estimated in the form of an equation to take into account the duration and the position of the intervention. Results: The estimated radiation doses received during 10 minutes of intervention emergency at a distance of 20, 40 and 60 cm from patient after different times post dose administration were in the range of 72.2 to 1207.5, 18.1 to 301.9 and 8.0 to 134.2 µSv, respectively. Conclusion: During the first ten hours following patient dose administration, the estimated emergency dose could be considered as high occupational dose value compared to the dose limit recommended by ICRP.