Investigation of Metals Bioaccumulation in Sediment and Fish Muscle of Dez River in 1393

The necessity of measuring elements in aquatic life comes from two aspects of ecological management and human nutritional health. In the present study, concentrations of Cu, Pb, Zn and Cd in sediments and muscle tissue of four native fish species of Dez River were studied to study metal contamination and its relationship with status factor (CF) and bioconcentration factor BCF). After bioassay of fish samples, digestion of the samples was performed by combining one to four nitric acids with perchloric acid and the concentration of the elements was measured by an absorbent apparatus.On the other hand, CF values ​​were lower than the thresholds introduced for salmonids. Also comparisons of Zn concentrations in sediments are higher than the world standard CaISQG and tolerable IAEA-407 levels and in muscle tissue, Zn and Cd concentrations are higher than UK standards (MAFF) and NHMRC, respectively, indicating dangerous levels. They are for human health. Fidings: The mean concentrations of metals in sediments and muscle tissue showed a decreasing trend for Cd, Pb, Cu, Zn and Pb, Cd, Cu, respectively. Statistical analysis of the results showed the highest correlation between the accumulation of metals and CF in the twin species and the highest loading of its contamination by calculating the MPI index. The resulting BCF also shows a decreasing trend in the uptake of cadmium, zinc, copper and lead from the environment. Discussion & It seemsthat the conditions of the study area from Dez River are unfavorable for fish compared to free waters and high cadmium concentration in studied samples can be due to effluent. The farmland overlooks the river.