Abstract
Risk assessment of soil contaminated with radionuclides was performed by considering the intake of radionuclides in foods based on measured concentrations. Due to the disaster at the Fukushima nuclear power plant on March 11, 2011, radionuclides were spread out. The radionuclides were found in the food, and the Japanese people are concerned about eating foods from Fukushima and the surrounding area. Radionuclides such as 134Cs and 137Cs were found on soil, buildings, plants, and so on. The exposure routes were determined to be food intake, ingestion and inhalation of soil particles, and external radiation from the ground. Then, the total doses of all exposure routes for one year were calculated, and the committed effective doses for the lifetime were evaluated. As a result, exposures by ingestion and inhalation of soil particles were negligible, and exposure by food intake and external exposure from the ground were comparatively large. This study shows that the air dose by this disaster should be less than 0.2 μSv/h to control the radiation dose with the consumption of food being less than 1 mSv/y. The risk assessment based on land use can provide information about the priority of countermeasures against the contamination and provides reasonable decontamination methods or risk management strategies.
