The long-term consequences of the nuclear disaster at the Fukushima Daiichi Nuclear Power Plant (FDNPP) that occurred on March 2011, have been scarcely studied on wildlife. We sampled Japanese tree frogs (Dryophytes japonicus), in a 50 –km area around the FDNPP to test for an increase of DNA damages and variation of DNA methylation level. The ambient dose rate ranged between 0.4 and 2.8 μGy h⁻¹ and the total estimated dose rate absorbed by frogs ranged between 0.33 and 7.67 μGy h⁻¹. Frogs from contaminated sites exhibited a dose-dependent increase of global genomic DNA methylation level (5-mdC and 5-hmdC) and of mitochondrial DNA damages. Such DNA damages may indicate a genomic instability, which may induce physiological adaptations governed by DNA methylation changes.

This study stresses the need for biological data combining targeted molecular methods and classic ecotoxicology, in order to better understand the impacts on wildlife of long term exposure to low ionizing radiation levels.

2011年3月发生的福岛第一核电站（FDNPP）核灾难的长期后果，很少在野生动植物上进行研究。我们在FDNPP周围50公里的区域采样了日本树蛙（Dryophytes japonicus），以测试DNA损伤的增加和DNA甲基化水平的变化。环境剂量率介于0.4至2.8μGyh ^-1之间，青蛙吸收的总估计剂量率介于0.33至7.67μGyh ^-1之间。来自受污染部位的青蛙表现出剂量依赖性的全球基因组DNA甲基化水平（5-mdC和5-hmdC）和线粒体DNA损伤的增加。此类DNA损伤可能表明基因组不稳定，可能导致受DNA甲基化变化控制的生理适应。

这项研究强调需要结合目标分子方法和经典生态毒理学的生物学数据，以便更好地了解长期暴露于低电离辐射水平对野生生物的影响。