determine of heavy metals in different tissues of black fish (capoeta fusca) in central part qanats of birjand

the aim of this study was measuring the amount of heavy metals (nickel, cobalt, cadmium, chromium and zinc) in different tissues of black fish (capoeta fusca). for this reason, in july 2010, 24 black fish was caught at the central part qanats of birjand. the results showed that between the whole length and the weight of fish and concentration of heavy metals in different observed tissues there were no significant correlation (p>0.05). however, there were significant differences between the concentration of metals (except nickel) in the observed tissues (p<0.05). the amount of heavy metals in muscle tissues of c. fusca was lower than standards of who and fao. in the other hands, zn has had the highest accumulation and cd has had the lowest accumulation in various tissues of c. fusca. the results, also, showed the most amount of accumulation of metals have been in liver and then gill tissues, while the lowest accumulation has been in the skin tissues. according to the investigations the results indicated that the amount of heavy metals in different tissues of black fish (c. fusca) in the eshkafto region was lower than other regions like mehdi abad, haji abad and noukand-e moud.