After the Tokyo Electric Power Company Fukushima Dai-ichi Nuclear Power Station accident, wild boar was found to have greater radiocesium (¹³⁷Cs) activity concentrations in their bodies than other wild animals in Japan; however, the reason for this remains unknown. To understand the mechanism of ¹³⁷Cs transfer from the environment to wild boar, and the factors that affect variation in ¹³⁷Cs contamination in wild boar, we sampled muscle and stomach contents from wild boar captured in Fukushima Prefecture and analyzed the relationships among ¹³⁷Cs concentrations in muscle tissue and in the stomach contents, ¹³⁷Cs ground deposition at capture sites, and wild boar food habits. Significant positive relationships were observed among ¹³⁷Cs activity concentrations in muscle and stomach contents, as well as ¹³⁷Cs deposition density at capture sites. These results suggest that ¹³⁷Cs is transferred from the environment to plant and animal materials consumed by wild boar, and then from these foods to the bodies of wild boar through digestion. However, no correlation was observed between ¹³⁷Cs concentrations in stomach contents and the presence of any particular food item in stomachs of wild boar, including mushrooms. These findings suggest mushrooms and underground food items, which were found to affect ¹³⁷Cs concentrations in wild animals in Europe, were not important contributors to high levels of ¹³⁷Cs contamination in Japanese wild animals.

东京电力公司福岛第一核电站事故发生后，发现野猪体内的放射性铯（¹³⁷ Cs）活性浓度高于日本其他野生动物。但是，其原因尚不清楚。为了了解¹³⁷ Cs从环境转移到野猪的机理，以及影响¹³⁷ Cs污染变化的因素，我们对福岛县捕获的野猪的肌肉和胃内容物进行了采样，并分析了¹³⁷ Cs浓度之间的关系。在肌肉组织和胃中¹³⁷CS在捕获地点的地面沉积以及野猪的饮食习惯。在肌肉和胃中的¹³⁷ Cs活性浓度与捕获位点的¹³⁷ Cs沉积密度之间观察到显着的正相关。这些结果表明，¹³⁷ Cs从环境转移到野猪消耗的动植物原料，然后通过消化从这些食物转移到野猪体内。但是，在胃中的¹³⁷ Cs浓度与野猪（包括蘑菇）的胃中是否存在任何特定食品之间没有相关性。这些发现表明蘑菇和地下食物被发现会影响¹³⁷欧洲野生动物中的Cs浓度并不是造成日本野生动物中¹³⁷ Cs污染水平高的重要因素。