Bioaccumulation of heavy metals levels in muscles of Rutilus frisii kutum and Cyprinus carpio Fishes of coastal waters of the Mazandaran Province, Caspian Sea

The proteins in fish، as well as other aquatic animals has nowadays become an important and complete protein sources in many people’s diets around the world and as a results، there has been a growing interest to protect and ensure the health of this important food source. Heavy metals due to their specific physical and chemical characteristics as well as their effects on various ecosystems are considered as a major contaminator of marine environments. Therefore determining the level of heavy metals in water and aquatic species، as a link in the food chain of human beings، is of a great importance. In this study، levels of some heavy metals were evaluated، using flame atomic absorption spectroscopy technique، in tissues of two commonly consumed fish in Iran namely Rutilus frisii kutum and Cyprinus carpio collected from the coastal waters of the Mazandaran Province، Caspian Sea. The average concentration of Ni and Cr were detected as (μg g-1) dry weight of Rutilus frisii kutum’s tissues: 1. 68 0. 28 and 0. 65 0. 12 (Mean Standard Error) respectively. These values for Cyprinus carpio were detected as: 1. 47 0. 22 and 0. 74 0. 19 (Mean Standard Error). These values were compared with the World Health Organization (WHO) safety reference standard regarding the amount of the above mentioned heavy metals in fish’s tissues. These values were compared with the WHO safety standards regarding the amount of the above mentioned heavy metals in fish tissues. Based on the results of this study، the concentration of Ni and Cr in the studied fish tissues proved to be much higher than international standards with a reliability of P<0. 05. The results show that the pollution in the water of this region are because of these heavy metals.