Investigation of Body Size Effect on Bioaccumulation Pattern of Cd, Pb and Ni in the Soft Tissue of Rock Oyster Saccostrea cucullata from Laft Port

Nowadays, contamination of heavy metals in aquatic ecosystems is one of the major world problems in developing and developed countries. Among various aquatics, shellfish species, especially bivalves can be used as bioindicator, because of purification system, potential bioavailability of impurities in environment as well as accumulation of some heavy metals in their body. Among bivalves, oysters are the most considered in research due to their nutrition importance. In this research, the concentrations of cadmium, nickel and lead were measured in rock oyster Saccostrea cucullata soft tissue (sizes from 2 to 7 cm) located in Laft Port using an ICP-OES instrument. Metal concentrations (µg/g DW for length class) of Cd, Pb and Ni were studied in S. cucullata to find the relationship with body size. The results of study revealed that smaller mussels in comparison to larger mussels showed higher concentrations of Ni and Pb. However, there was no significant difference between large and small oysters for Cd.According to EPA, FDA standards, the mean concentrations of Cd and Pb in the three categories of length were higher than the permissible limit and as such, its consumption could pose risk to humans and other organisms.