Trace metals level in sediments and bivalve Trachycardium lacunosum shell in the Persian Gulf

Abstract

The current investigation has monitored the concentration of Cd and Pb in bivalve Trachycardium lacunosum shells and the sediment samples in Asaluyeh Bay (north of the Persian Gulf). The samples were taken from 40 stations located in two sites in Asaluyeh region, Nayband Bay as a “contaminated” site and Lavar-e Saheli as a “control” site. The results showed that the mean concentration of Pb and Cd in the sediments were 3.56–5.25 and 1.16–1.44 μg/gdrw, respectively, and in the shell ranged from 11.30 to 13.71 and 2.38 to 2.75 μg/gdrw, respectively. Data indicated that contaminated site contained significantly higher concentration compared with the control site. There were significant positive correlations between the level of Pb and Cd in the shell as well as sediment samples. A biota-sediment accumulation factor of more than one indicated the occurrence of biomagnification of the studied metals in Nayband Bay. Therefore, the elevated amount of the sediments trace metals has led to bioaccumulation in the bivalve shell.