Assessment of some heavy metals concentrations in substrate sediments and muscle of farmed Rainbow trout (Oncorhynchus mykiss) on the margin of Bashar River (kohgiluyeh-Boyerahmad)

The dilemma of contaminating water resources with heavy metals has doubled the need to measure heavy metals in fish that reach in the food cycle to the human ecosystem. This study was conducted to determine the concentration of heavy metals (lead, mercury and cadmium) in sediments and trout flesh farmed on the banks used water of the Beshar River in Kohgiluyeh and Boyerahmad province. To measure the heavy metals, randomly sample  river sediments in the entrance area of water inlet  two rainbow trout farms in the lower part of the Beshar River and downstream of Yasouj and muscle tissue of fish in these farms. The total number of sediment samples and fish muscle were 64 samples (32 sediment samples and 32 fish samples). After transferring the samples to the laboratory and preparing, the atomic absorption apparatus was used according to the standard method to determine the concentration of heavy metals. The mean concentrations of mercury, cadmium and lead in fish muscle of the farms of Beshar River were 0.12±0.04 , 0.0041±0.0015  and 0.08±0.01 mg/kg, respectively. Concentrations of mercury, cadmium and lead in the trout of the Beshar rivers are below the FAO, EC, MAFF and FDA standards. Based on the results of this research and this situation, the fish of  the farms of the margin of Beshar River is healthy for human consumption and free from heavy metal contamination based on the  wourld standards.