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Trace metals (Al, Fe, Mn, Zn, Cu, Pb, Ni) accumulation and their dynamics in the system soil-rodents-cestodes from natural site located around complex Maritza Iztok were tracked. Accumulation factors (ratio of metals contents in rats to these in soil) and as well bioaccumulation factors in the host ��� parasite system (ratio of content of metals in cestodes to this in the rats) were calculated. Metal conten was determined in the soil, the liver of rats (infected and non-infected) and in the tapeworms. The accumulation factor was the highest for Zn followed of Cu and Pb. Cestodes Hymenolepis spp. have higher bioaccumulation capacity for toxic metals, than their infected host, especially for Ni. Data demonstrated an increase in pollution due to a coal industry in a region of Maritsa Iztok coal complex.