Heavy metals are one of the major pollution sources in the environment and pose constant threat to people and other living organisms. Mining areas are the most endangered and particularly highly exposed to the pollution. The good example of such area is a copper smelter plant "Legnica". Therefore, the aim of presented studies was the evaluation of toxicity within the area of smelter and, thus the evaluation of its impact on living organisms. The research hypothesis assumes that a copper smelter plant could have an adverse impact on the environment quality in the studied area. The studies were performed with ecotoxicological tests on plants and microorganisms. A potential susceptibility of the soil for the cultivation of crop plants was also assessed. In our studies the significant decrease in dehydrogenases activity was observed at studied sites, although the permissible concentrations of copper was exceeded at one site only. The toxic effect on the lenght and development of examined plants was also recorded. Results show that heavy metals deriving from the copper smelter plant can still considerably influence the soil quality and living organisms.