Low levels of Fukushima Dai-ichi NPP-derived radiocesium in marine products from coastal areas in the Sea of Japan (2012-2017)

Abstract

Radiocesium concentrations in marine biota in coastal areas of the Sea of Japan were < ~0.005-0.02 Bq/kg-wet and ~0.01-0.18 Bq/kg-wet for ¹³⁴Cs and ¹³⁷Cs, respectively (2012-2017). The biota-seawater concentration factors were ~25-100, which approximately agreed with those of ¹³⁷Cs recorded before FDNPP accident. The low levels of ¹³⁴Cs in marine biota were likely taken up from ambient seawaters. The total of radiocesium concentrations is now equivalent to that in the 1990s based on the ambient water data.

Keywords: Concentration factor; Fukushima Dai-ichi Nuclear Power Plant accident; Marine biota; Radiocesium; Sea of Japan.