Radiocesium concentrations in the muscle and eggs of salmonids from lake Chuzenji, Japan, after the Fukushima fallout

Abstract

Approximately 18 months (September–December 2012) after the Fukushima Dai-ichi Nuclear Power Plant accident, elevated radiocesium concentrations were detected in muscle and egg samples from masu salmon (Oncorhynchus masou), kokanee (Oncorhynchus nerka), brown trout (Salmo trutta), and lake trout (Salvelinus namaycush) from the Lake Chuzenji system, central Honshu Island, Japan (160 km from the station). Mean muscle concentrations were 142.9–249.2 Bq/kg-wet, and mean egg concentrations were 38.7–79.0 Bq/kg-wet. No relationship between fork length and muscle radiocesium concentration was observed in any of the species, but significant relationships were found between individual muscle and egg radiocesium concentrations from masu salmon, brown trout, and lake trout.