Follow-Up on Fukushima
Photo Credit: WHOI
A new scientific study published in the October issue of Integrated Environmental Assessment and Management, Jordi Vives i Batlle describes the status of research and findings on the impacts of the Fukushima Daiichi Nuclear Power Plant accident that occurred five years ago in Japan. It is estimated that 80% of the radioactive discharge fallout was over the Pacific Ocean, striking concern for the long-term impacts on marine life.
The impacts of radioactivity on marine organisms throughout the food chain are influenced by a few key factors: How long the organisms are exposed to the material, the size and species of the organisms, which radioactive isotopes are present, the temperature and salinity of the water, the oxygen content of the water, and other complicated factors including organism life stage. To learn more about ways radioactive compounds can impact marine life, visit this article from the Woods Hole Oceanographic Institution: http://www.whoi.edu/oceanus/feature/how-is-fukushimas-fallout-affecting-marine-life.
A major concern after the fallout in 2011 was whether there would be negative impacts on the fisheries stocks. In March of 2016, The Japan News reported fish and other sea life were “thriving” and that scientists had not recorded any decrease in biodiversity in affected areas. Read this article here: https://news.vice.com/article/five-years-after-the-fukushima-disaster-the-fish-are-proliferating.
Now, the study by Vives i Batlle reports that radioactivity levels in marine life are lower than earlier predictions following the accident and the exposure may have been too low to elicit acute population effects. However, several studies have shown variability in radioactivity levels in fish, which may reflect differences in the fishes position on the food chain, migratory patterns, or life stage. In addition, sources of radioactive from delayed sources entering the ocean (sediments and groundwater, for example) are not well understood. Although these studies are reporting good news for marine organisms, research is still required to understand long-term effects and how organisms are responding in the areas with the highest levels of fall out.