STUDY OF THE BIOACCUMULATION OF HEAVY METALS IN ASTACUS LEPTODACTYLUS IN SOME AREAS OF THE KARDZHALI DAM

It is examined the contents of lead, cadmium and nickel in the water of Kardzhali dam, as well as the bioaccumulation of the heavy metals in two organs – liver and muscles of Astacus leptodactylus. In tissue samples is reported increasing of cadmium in samples of liver. The bioaccumulation coefficient was calculated on the basis of the average content of lead, cadmium and nickel in the organs of Astacus leptodactylus. We recorded that the studied crayfish are macroconcentrators for cadmium.The analyzes have shown that lake crayfish to be defined as a biomarker in toxicity testing in contaminated waters.