Radiocesium concentration ratios and radiation dose to wild rodents in Fukushima Prefecture

Radiocesium was dispersed from the Fukushima Dai-ichi disaster in March 2011, causing comparatively high radioactive contamination nearby environments. Radionuclide concentrations wild rodents (Apodemus argenteus, and Apodemus speciosus) within these areas were monitored 2012 to 2016. However, whole-organism soil transfer parameters (i.e., concentration ratio, CRwo-soil) for at not determined hence lacking international databases. We augmented 2012–2016 data by collecting activity (Bq kg?1, dry mass) five rodent sampling sites Prefecture, developed corresponding CRwo-soil values radiocesium (134Cs 137Cs) based on radioactivity fresh mass). The added Wildlife Transfer Database (WTD; http://www.wildlifetransferdatabase.org/), supporting development of International Commission Radiological Protection's (ICRP) environmental protection framework, increasing WTD 84 477 entries cesium Muridae (‘Reference Rat’). Significant variation occurred between study Prefecture. geometric mean CRwo-soil, this paper, higher than that reported species Chernobyl. Radiocaesium absorbed dose rates also estimated inhabiting ranged 1.3 33 ?Gy h?1. Absorbed decreased a factor two Dose highly contaminated ICRP derived consideration reference level Reference Rat (0.1–1 mGy d?1), suggesting possible occurrence deleterious effects need radiological effect studies area.