Radiation dose assessment of the uranium rich regions in Korea

Abstract

The radiation dose was assessed for the inhabitants living in the Kumsan, Geosan and Miwon regions which belong to an Okchun metamorphic belt with plenty of uranium resources. The grain, vegetable, milk, and water, which the inhabitants generally ate or drunk, were sampled to reflect the dose effects. And TLD (Thermoluminescence dosimeter) was used for measuring the external dose in the sampled area. An external exposure includes the accumulated gamma dose measured by TLD and an internal exposure includes an ingestion of the food, and an inhalation of the air and radon gas. The radionuclides such as 137Cs, 7Be, 40K as well as 238U were included for measuring the radioactivity concentrations of the samples. Radioactivity concentrations for the samples were calculated as averaged annual values. The effective dose by TLD analysis was similar to the domestic average when considering that it was between 0.63 mSv/y and 0.71 mSv/y. The 222Rn concentration of indoor air significantly contributed to the total effective dose where the concentration of these uranium belt regions was more or less higher than the average domestic one. This study revealed that the dose level for the inhabitants of the uranium rich regions in Korea was similar to that of the other regions except for the effect by radon.