Experimental Studies on the Bioaccumulation of Selected Heavy Metals and Radionuclides in the Blood Cockle Anadara granosa of the Bang Pakong Estuary

Abstract

Biokinetic experiments of essential metal (65Zn), heavy metals (51Cr, 203Hg) and anthropogenic radionuclides (57Co, 85Sr, and 134Cs) on Anadara granosa from Bang Pakong estuary were performed under controlled conditions (salinity 30 psu, temperature 28.5 ±1.5°C and pH 8.0 ±0.1). The results showed that A. granosa accumulates studied metals and radionuclides efficiently, except 85Sr and 134Cs. Uptake of 51Cr, 57Co and 65Zn in A. granosa displayed saturation kinetics with estimated whole-body steady-state concentration factors (CFss) of 24, 730, and 90, respectively. Accumulation of 203Hg by A. granosa followed a simple linear model (R2 = 0.83), with maximum concentration factor (CFM) of 166. Loss kinetics of 57Co, 65Zn and 203Hg were best described by a 2-component exponential model, with computed half lives for long-lived component ranging from 99 to 125 d, whereas loss kinetics of 51Cr was best described by a single exponential model with computed half life of 16 d. 51Cr, 57Co and 65Zn were distributed r...