Interaction of Essential and Nonessential Metals in Tissues of Rutilus Frisii Kutum from Southwestern Basins of the Caspian Sea

Interactions between some essential (copper and zinc) and non-essential metals (cadmium and mercury) were examined in muscle and liver tissues of kutum. Fish samples were taken in fishing seasons (February through March 2009) at the southwestern coasts of the Caspian Sea (Guilan province). Mercury (Hg) levels were determined following cold vapor technique and concentrations of Cu, Cd and Zn were measured by atomic absorption (Thermo Electron Corporation, GFS 97) in µg.gr-1dry body weight. Except for Cd which was recorded only in livers, there was no significant correlation between metal concentrations in liver with concentration of the same metal in muscle tissues. It seems that increase in concentration of Zn is correlated with increase in accumulation of Hg and Cd in livers. Moreover, increase in concentration of Cu in livers resulted in significant increase in Hg levels both in liver and muscles. Based on the obtained results it seems that interactions between metals in fish tissues influence accumulation of essential and toxic metals.