Optimization of In-vivo Monitoring Program for Radiation Emergency Response

Abstract

Background: In case of radiation emergencies, internal exposure monitoring for the members of public will be required to confirm internal contamination of each individual. In-vivo monitoring technique using portable gamma spectrometer can be easily applied for internal exposure monitoring in the vicinity of the on-site area.

Materials and Methods: In this study, minimum detectable doses (MDDs) for 134Cs, 137Cs, and 131I were calculated adjusting minimum detectable activities (MDAs) from 50 to 1,000 Bq to find out the optimal in-vivo counting condition. DCAL software was used to derive retention fraction of Cs and I isotopes in the whole body and thyroid, respectively. A minimum detectable level was determined to set committed effective dose of 0.1 mSv for emergency response.

Results and Discussion: We found that MDDs at each MDA increased along with the elapsed time. 1,000 Bq for 134Cs and 137Cs, and 100 Bq for 131I were suggested as optimal MDAs to provide in-vivo monitoring service in case of radiation emergencies.

Conclusion: In-vivo monitoring program for emergency response should be designed to achieve the optimal MDA suggested from the present work. We expect that a reduction of counting time compared with routine monitoring program can achieve the high throughput system in case of radiation emergencies.