Soil pollution with heavy metals in industrial and agricultural areas: a case study of Olkusz district

Soil contamination of areas covered by industrial plants and farms is one of the major environmental problems whose weight is underestimated in Poland and Europe. Such regions are usually not as exposed to direct pollution as highly urbanized industrial areas. On the other hand, they are usually less strictly monitored than protected areas. The District of Olkusz, an example of such a region, is characterized by well-developed agriculture, regressing local industry and growing tourism industry. However, it borders with Silesia, a heavily industrized area. The study reports the condition of arable soils in Olkusz District in terms of their contamination with lead, cadmium, zinc and copper. The atomic absorption spectrometry (AAS) method was used to determine the concentrations of the metallic elements. The parameters like pH, content of the clay fraction and content of organic matter have been also taken in consideration to assess the bioavailability of the metals. The analytical results showed that, despite the decreasing impact of the local industry, levels of concentration of all the studied metals are significantly higher than their average concentration in Polish soils. Moreover, all the calculated Pearson correlation coefficients between concentrations of the metals were above 0.9, which means they correlate each other strongly. The impact of the local pollutants (mainly Bukowno smelter) in connection with the proximity of the Silesia and the high vulnerability for contamination of the soils precludes agricultural use of the ground in at least half of the cases.