Abstract
The Fukushima Daiichi Nuclear Power Plant (FDNPP) accident that occurred after the Great East Japan Earthquake in March 2011 released large quantities of radionuclides to the environment. The long-term effects of radioactive cesium (Cs) on biota are of particular concern. We investigated the accumulation of radioactive Cs derived from the FDNPP accident, and chronic effects of environmental radionuclides on male reproduction, in the large Japanese field mouse (Apodemus speciosus). In 2013 and 2014, wild mice were captured at 2 sites in Fukushima Prefecture and at 2 control sites that were distant from Fukushima. Although the median concentrations of 134Cs and 137Cs in the mice from Fukushima exceeded 4,000 Bq/kg, there were no significant differences in the apoptotic cell frequencies or the frequencies of morphologically abnormal sperm among the capture sites. Thus, we conclude that radiation did not cause substantial male subfertility in Fukushima during 2013 and 2014, and radionuclide pollution levels in the study sites would not be detrimental to spermatogenesis of the wild mice in Fukushima.
Highlights
The Fukushima Daiichi Nuclear Power Plant (FDNPP) accident that occurred after the Great East Japan Earthquake in March 2011 released approximately 500 PBq of 131I, 10 PBq of 134Cs, and 10 PBq of 137Cs to the environment1. 137Cs has a relatively long half-life of approximately 30 years; the long-term effects of its gamma ray emissions on biota are of particular concern
In this study we investigated the accumulation of radioactive Cs derived from the FDNPP accident in large Japanese field mice, and the chronic effects of environmental radionuclides for male reproduction, focusing on germ cell apoptosis and sperm morphology
The majority of the radioactive materials derived from the FDNPP accident were deposited in the upper soil layer and plant litter in the forest[20]
Summary
The Fukushima Daiichi Nuclear Power Plant (FDNPP) accident that occurred after the Great East Japan Earthquake in March 2011 released approximately 500 PBq of 131I, 10 PBq of 134Cs, and 10 PBq of 137Cs to the environment1. 137Cs has a relatively long half-life of approximately 30 years; the long-term effects of its gamma ray emissions on biota (such as wild animals) are of particular concern. In Fukushima, as in most of the Japanese mainland with the exception of highlands, they typically breed twice yearly, in spring and autumn[10,11,12] Their maximum life span in the wild is estimated to be 26 months[13]. Organisms within the zone of greatest atmospheric deposition (25–45 km northwest from FDNNP) were predicted to be exposed to considerable radiation for the first 30 days after the accident; forest rodents were exposed to 3.9 mGy/day during that period[19] This value is within the “reduced reproductive success” level, which ranges from 1 to 100 mGy/day for rodents[3]. In this study we investigated the accumulation of radioactive Cs derived from the FDNPP accident in large Japanese field mice, and the chronic effects of environmental radionuclides for male reproduction, focusing on germ cell apoptosis and sperm morphology.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
