Development of portable thyroid monitoring system for ¹³¹I and ¹³³I in nuclear emergency

In the event of emergency situation such as leakage of radionuclides from nuclear power plant, it has the potential for significant radiation exposure in large populations. ¹³¹I and ¹³³I are major release radionuclides in a nuclear emergency and they are accumulated in the human thyroid. Therefore it is important to measure the iodine including short-lived radioiodine rapidly in the case of large casualties. The purpose of this study is to establish a thyroid monitoring system for emergency situation and to evaluate the factors influencing counting efficiency using Monte Carlo simulation of radiation transport in the mathematical phantom and the radiation detector. (author)