Investigation of radiocesium biokinetics in Manila clam (Ruditapes philippinarum)

Abstract

This study was carried out to better understand the biokinetics of radiocesium in clams living in sediment. The accumulation and depuration kinetics of Cs-134 were investigated in the Manila clam (Ruditapes philippinarum) under controlled laboratory conditions. The concentration factor was found to be 3.0 for Cs-134 in the whole body; however, the concentration factor in the soft part of the clams (12) was significantly higher than those in the whole body and shell (0.80). The depuration kinetics of the radionuclide were described by a two-component exponential model for the whole body. The biological half-lives in the fast and slow components were found to be 0.63 and 22.1 days, respectively. The depuration kinetics for Cs-134 in the soft parts were described by a single-component exponential model with a resultant the biological half-life of 18.0 days.