Bioaccumulation of heavy metals (lead and nickel) in muscle tissue Luciobarbus capito in Sefidroud river

The largest river in the southern basin of the Caspian Sea is Sefidroud, and the most important native fish of that river is the large head sea bass. Due to its long route and passing through different areas, this river is exposed to various contaminants including heavy metals. The aim of this research was to investigate the amount of bioaccumulation of lead and nickel heavy metals in L. capito muscle tissue in Sefidroud river. Three stations were selected along the route and in four seasons, 45 fish were caught by throwing nets. The samples were transferred to the laboratory in standard conditions and after biometrics, samples were taken from their muscles and the amount of these metals was determined by chemical digestion method and with the help of atomic absorption device. The results showed that the fishes caught in Sefidroud river in different seasons and stations were in the age range of +1, +3 and their average total weight was 221.72 ± 21.82 gr and their average total length was 25.19 ± 1.97 cm. The concentration of lead heavy metal L. capito in the muscle of Sefidroud 0.58±0.1 μg/g per gram of muscle and the mean test with one-way variance showed a significant difference between the stations in the seasons (P<0.05). The average nickel concentration in the muscles of one year was 4.1±83.4 μg/g of muscle, and the mean test with one-way variance showed a significant difference between the stations in the seasons (P<0.05). According to these results, the concentration of lead is low and according to the standards of consumption, it shows the permissible amount, but the amount of nickel in the muscles of Sefidroud big head fish sauce is high and even the safe consumption values ​​of some indicators have shown higher numbers.