Unexpected source of Fukushima-derived radiocesium to the coastal ocean of Japan

Research Highlight

Coastal groundwater spreads nuclear pollution

©Taro Hama @ e-kamakura/Moment/Getty

©Taro Hama @ e-kamakura/Moment/Getty

Groundwater beneath sandy beaches continues to be a significant reservoir for radioactive cesium following Japan’s 2011 nuclear disaster, when the Fukushima Daiichi nuclear power plant suffered multiple reactor meltdowns after it was hit by a tsunami. 

Eight beaches close to the plant have been sampled by a US-Japan team, including Seiya Nagao from Kanazawa University. The group found that groundwater under all eight beaches contained more radioactive cesium than the water of nearby rivers, inland groundwater reserves or surrounding ocean waters.

It’s suspected that beach sands retained radioactive cesium deposited by highly irradiated seawater in the days and weeks following the disaster and that this reached the water beneath it.

Evidence of this ‘new’ route through which radioactive elements can make their way into the environment will likely help inform future environmental monitoring efforts and emergency planning strategies. The finding is also ripe for further examination as half of the world’s 440 nuclear reactors are found in coastal locations. 

Supported content

  1. Proceedings of the National Academy of Sciences of the USA 114, 11092–11096 (2017). doi: 10.1073/pnas.1708659114
Institutions Share
Department of Marine Chemistry and Geochemistry (MC&G), WHOI, United States of America (USA) 0.75
Kanazawa University (KU), Japan 0.25