In our PhD thesis we investigated the behaviour of solid carriers of potentially toxic elements (PTEs) in an environment contaminated by mining and industrial activities. The properties of solid potential inorganic pollutants (SPIPs) depend on the sources and processes of formation and further processes in the transport medium or disposal environment. We have chosen the Upper Mežica Valley (UMV) as the study area, where the environment is contaminated with PTEs from former Pb-Zn ore mining and smelting and from the current industry for recycling of secondary Pb raw materials and production of Pb batteries. In this work, we determined the microchemical and micromorphological properties of SPIPs at the level of individual particles in air, precipitation, road dust and soil. The purpose of defining these properties was to determine what changes SPIPs undergo during transport between environmental media and how these can be detected at the micro- and submicron level. The understanding of the changes of SPIPs in the natural environment was complemented by laboratory experiments on the alteration of minerals and phases (galena, sphalerite, pyrite, anglesite, plattnerite) in soil under simulated conditions. In the atmosphere, we identified numerous Pb phases (sulphides, sulphates, oxides/carbonates, chlorides/chlorates/chloride carbonates/chloride hydroxides), complex Pb, Sb and Sn oxides, Zn sulphide, silicates and Fe oxides/oxyhydroxides with PTEs. The morphological changes showed that most phases change gradually and slowly, as they are detectable in the environment even after they have been deposited in road dust or soil. In soil, SPIPs were dominated by ore minerals and their secondary forms. Among the more stable phases, we found phosphates, Fe and Mn oxides/oxyhydroxides as sink of PSP. The isotopic composition of Pb in soil is most strongly influenced by ore minerals, while in road dust we found a mixture of several sources. In a laboratory experiment, we found that under simulated soil conditions, galena and anglesite dissolve intensively, while the changes in sphalerite and pyrite were less noticeable. These results are in contrast to the findings on the changes of SPIPs under natural conditions. Plattnerite showed tendency to transformation to carbonate phases. Additional analytical and methodological approaches could help us in the future with a detailed chemical characterization of individual SPIPs and their changes in the environment.
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