A Comparative Study of Heavy Metals (Ni, Cd, Pb) Bioaccumulation in Soft Tissue and Shell of Shrimp in Shrimp Farms of Bushehr Province

The main objective of this research was to study three heavy metals (nickel, cadmium and lead) in the shrimp’s muscle tissue and shell. This research was conducted in shrimp farms of Bushehr Province in 2009.
Muscle tissues and the shells of the collected samples were separated, dried in oven and after grinding were digested in acid until they reached the volume, and then flame atomic absorption spectroscopy was used to assess the level of metals in the tissues and shells.
Findings: The findings of this study show an average of 0.2 and 0.5 milligram per kilo (wet weight) of cadmium in tissue and shell; 1.92 and 4.82 milligram per kilogram (wet weight) of lead; and 1.4 and 5.5 milligram per kilogram (wet weight) of nickel in tissue and shell respectively. A comparison of the results with the international standards of the World Health Organization, British Ministry of Agriculture, Fishing and Food and Australian National Medical, Health and Research Association and that of the European Union shows that the concentration of these metals is below the permitted level. Meanwhile, the results show a reverse linear relationship between the accumulation of the three metals in shell texture and the passage of time. Also there is a reverse linear relationship between accumulation of cadmium in the muscle tissue and the passage of time. But a direct linear relationship was observed between accumulation of lead and nickel in the muscle tissue and the passage of time. Moreover, a significant relationship was found between accumulation of cadmium and lead in the muscle tissue and the passage of time. Also a significant relationship was found between accumulation of cadmium in the shell and the passage of time.