Spatiotemporal change of cesium-137 in the Pacific coast of Tohoku, Japan: The mussel watch approach

Naoko Murakami-Sugihara; Kotaro Shirai; Hirofumi Tazoe; Kaoruko Mizukawa; Hideshige Takada; Takeyasu Yamagata; Shigeyoshi Otosaka; Hiroshi Ogawa

doi:10.1016/j.marpolbul.2021.112413

Spatiotemporal change of cesium-137 in the Pacific coast of Tohoku, Japan: The mussel watch approach

Mar Pollut Bull. 2021 Jul:168:112413. doi: 10.1016/j.marpolbul.2021.112413. Epub 2021 May 24.

Authors

Naoko Murakami-Sugihara¹, Kotaro Shirai², Hirofumi Tazoe³, Kaoruko Mizukawa⁴, Hideshige Takada⁴, Takeyasu Yamagata⁵, Shigeyoshi Otosaka², Hiroshi Ogawa²

Affiliations

¹ Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8564, Japan. Electronic address: nsugihara@aori.u-tokyo.ac.jp.
² Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8564, Japan.
³ Institute of Radiation Emergency Medicine, Hirosaki University, 66-1, Hon-cho, Hirosaki, Aomori 036-8564, Japan.
⁴ Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu, Tokyo 183-8509, Japan.
⁵ The University Museum, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.

PMID: 34038820
DOI: 10.1016/j.marpolbul.2021.112413

Abstract

We measured radiocesium in mussel tissue collected from the Pacific coast of Tohoku from 2011 to 2015 to investigate the temporal and spatial dynamics of radiocesium in the coastal area. Radioactive ¹³⁷Cs was detected in all the samples collected in 2011, but it was not found in samples from localities north of Sendai after 2012. In contrast, ¹³⁷Cs was detected in many sites in the Fukushima area even from 2012 to 2015. The fluctuation of ¹³⁷Cs concentration in mussel tissue seems to reflect the ¹³⁷Cs concentration in suspended particles in the seawater, suggesting that there was an influx of soil deposition and resuspension of seabed sediment. These results suggest that the ¹³⁷Cs concentration in mussel tissue sensitively indicates the ¹³⁷Cs concentration in the environment, and that the "mussel watch" approach is an effective way to understand the dynamics of radiocesium concentrations in coastal areas.

Keywords: Coastal area; Fukushima; Mussel watch; Radiocesium.

MeSH terms

Animals
Bivalvia*
Cesium
Cesium Radioisotopes / analysis
Fukushima Nuclear Accident*
Japan
Radiation Monitoring*
Water Pollutants, Radioactive* / analysis

Substances

Cesium Radioisotopes
Water Pollutants, Radioactive
Cesium
Cesium-137