Accumulation of heavy metals in rainbow trout, Oncorhynchus mykiss (Walbaum, 1792)

Accumulation of heavy metals in Rainbow trout, oncorhynchus mykiss (Walbaum, 1792) This study has been done between February 2013-Februrary 2014 on rainbow trout samples obtained from fish farms on Keban and Karakaya Dam Lakes. During the study, 20 fish samples from Keban Dam Lake and 20 fish samples from Karakaya Dam Lake were obtained. The study was conducted in laboratories of Fisheries Research Station, Firat University, Faculty of Fisheries and Environmental Engineering. Fish samples were taken from fish farms on the Keban and Karakaya Dam Lakes and they were brought to laboratory. Their total, fork and standard lengths, weight and sex were determined. Then,5 g muscle tissue from nearly 2 cm bottom of dorsal fins was sampled from each fish for the determination of heavy metal accumulation. Muscle samples were placed in the labelled plastic bags and kept in a deep freezer until the analysis phase. To make heavy metal analysis in the samples, they were mineralized in a microwave oven after adding of 5 ml of 65% nitric acid and 5 ml of concentrated sulphuric acid. Then they were cooled and diluted to 50 ml with distilled water. The analysis of iron (Fe), Cupper (Cu), Lead (Pb) and Manganese (Mn) in the diluted samples were done by a Atomic Absorption Spectrophotometer in Environmental Engineering Laboratory. Standard solutions were also prepared. Evaluation of the data obtained during the study was performed using the statistical Minitab Version 16 program and on the basis of the findings in the Student T-test, chi-square test was performed seasonally. In all samples, copper (Cu) and lead (Pb) were below the detection limit. The levels of heavy metals were found as Zn> Fe> Mn> C=Pb. In addition, the amounts of all heavy metals detected were found to be lower than the amounts suggested in various standards. Therefore, it was concluded that there is no any risk for environment and public health during the levels of Fe, Cu, Zn, Mn and Pb stayed in the present values. Key Words: Keban Dam Lake, Karakaya Dam Lake, Rainbow trout, Heavy metal