ASSESSMENT OF MERCURY POLLUTION IN SOILS ALONG JALA AND SPREČA RIVER BANKS IN BOSNIA AND HERZEGOVINA

The objective of this work was to determine the degree of mercury contamination in soils collected from the banks of Jala and Spreča Rivers and the extent to which the soils quality has deteriorated. As possible source of this hazardous heavy metal, it was also investigated the pollution of soils in the area of Ltd. Polihem plant, in which Hg was applied as cathode in process of chlorine-alkali electrolysis during a period of 1977-1992. Mercury content of 3,864 g/kg in soil near electrolysis plant was measured. The extent of soils quality deterioration was observed in all the sampling points from river banks below Ltd. Polihem, which demonstrates that the contamination may be attributed mainly to wastewater dispersion of mercury from factory. The levels of mercury decreased with an increase in distance of sampling points from Ltd Polihem. In this study, metal in the soil was determined using ICP-OES method. The study revealed that Hg levels were higher than the EU Directives proposed limit. The mercury contamination in the soils was also evaluated by applying enrichment factor (EF), contamination factor (CF), geo-accumulation factor (Igeo) and pollution-load index (PLI). Based on EF, the soils from river banks have moderate to extremely high enrichment factor. According to CF, mercury is responsible for significant contamination to very high. According to Igeo, soils are moderately to extremely poluted by Hg. Based on PLI, all sampling sites suggest overall pollution of site quality. Depending on Hg content, these soils cannot be recommended for agricultural activities because the accumulated metal in the soil may risk the agricultural plants. It is most likely that the foodstuff in this study environment might be at the highest risk of induced mercury contamination, which may have hazardous effect on human health.