Radiocaesium transfer and radiation exposure of frogs in Fukushima Prefecture

Tagami, K; Uchida, S; Wood, MD; Beresford, NA

Abstract

The International Commission on Radiological Protection has proposed an environmental assessment framework. This includes ionising radiation exposure assessment for different frog life-stages, but radiocaesium transfer parameters are unavailable. We collate data from the Fukushima Prefecture (contaminated by the Fukushima accident) and estimate radiocaesium concentration ratio (CR ) values for tadpoles and adult frogs, presenting the largest available amphibian CR dataset. In total, 513 adult frogs and 2540 tadpoles were analysed in 62 and 59 composite samples respectively. Results suggest that equilibrium was reached between water and amphibian radiocaesium activity concentrations circa one-year after the accident. Radiocaesium transfer to tadpoles was higher than to adult frogs. Dose rates were estimated for different life-stages and species in both the aquatic and terrestrial environment. Estimated dose rates to adults and tadpoles were typically similar because external exposure dominated for both organisms; frogspawn dose rates were estimated to be orders of magnitude lower than other life-stages. For the two sites assessed, which were outside of the most contaminated areas of the Fukushima Prefecture, estimated dose rates were below those anticipated to present a risk to wildlife populations; it is likely that dose rates in more contaminated areas were in excess of some effects benchmark values.

Citation

Tagami, K., Uchida, S., Wood, M., & Beresford, N. (2018). Radiocaesium transfer and radiation exposure of frogs in Fukushima Prefecture. Scientific reports, 8(1), 10662. https://doi.org/10.1038/s41598-018-28866-0

• Journal Article Type: Article
• Acceptance Date: Jun 29, 2018
• Online Publication Date: Jul 13, 2018
• Publication Date: Jul 13, 2018
• Deposit Date: Jul 25, 2018
• Publicly Available Date: Jul 25, 2018
• Journal: Scientific Reports
• Print ISSN: 2045-2322
• Publisher: Nature Publishing Group
• Volume: 8
• Issue: 1
• Pages: 10662
• DOI: https://doi.org/10.1038/s41598-018-28866-0
• Publisher URL: https://doi.org/10.1038/s41598-018-28866-0
• Related Public URLs: https://www.nature.com/srep/
• Additional Information: Funders : Natural Environment Research Council (NERC);Agency for Natural Resources and Energy, the Ministry of Economy, Trade and Industry (METI), Japan; Projects : NE/L000520/1;NE/L000318/1