Measurement of Pollution Levels Caused by Heavy Metals of Vanadium, Nickel, Lead and Copper Using Bivalve Shells of Timoclea imbricata Species On Bahrakan Coast in Spring 2013

Background: Bivalves have been used to study pollution level caused by heavy metals due to their biological characteristics. Bahrakan region includes Bahrakansar, Hendijan, Norouz and Soroush oil fields, and current information regarding sea management, especially from the protective aspect is very little. Objectives: This study aimed to assess region pollution with heavy metals. For this purpose, pollution caused by heavy metals in bivalves was assessed and compared with the standard values. Materials and Methods: Bivalve sampling was performed using Grab to determine the pollution content with heavy metals of vanadium, nickel, lead and copper in five different stations on 15 samples (3 samples for each station) in spring 2013. The digestion process was completed using the Yap method, then the concentrations of mentioned metals were measured using the ICP device in each of digested samples. Results: Nickel (13.12 ± 6.07 mg/kg) had the highest total average concentration and the lowest for lead (1.15 ± 0.28 mg/kg). Concentrations of nickel, vanadium and lead were higher than the WHO international standards, but much lower for copper regarding the same standards. Concentrations of nickel and vanadium were higher than copper compared to FAO, but lower than lead regarding the presented allowable limit. Conclusions: Nickel and vanadium had the highest concentration among other metals. Since these two metals are used as oil pollution parameters and the region is rich in oil, it can be concluded that oil pollution is present in the region. The existing oil pollution threatens all the living organisms in the area. Therefore, it would be of great importance to examine pollution sources of this region. The results can be used to constantly monitor the amount of heavy metals in bivalves of Timoclea imbricate species in this region.