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The enterprises of the power industry worked by coal are one of the active sources of environmental pollution with heavy metals. The Novocherkassk State Power Station is the biggest power industry in the South of Russia. The atmospheric emissions contain heavy metals including Cu. Copper in soils exists in different chemical forms or types of binding. In environmental studies, the determination of these forms gives more information on trace metal mobility, as well as on their availability and toxicity, in comparison to the total element content. Monitoring plots are occupied by Haplic Chernozem at distances of 1.6 and 15 km along the main northwest direction wind from the Power Plant. Soil samples were taken from a depth of 0-20 cm. Analysis of Cu compounds in the soils was carried out by the Tessier's method (1979), which is one of the most common procedures used for sequential fractionation. It is found that the soil located at a distance of 1.6 km from the Power Station is exposed to active influence of aerosol emission. At a distance of 15 km from the Station, its impact on the soil is reduced significantly. The distribution of Cu factions in the unpolluted soil has the following sequence: residual (51% of the sum of fractions) > bound to organic matter (28%) > bound to Fe- Mn oxides (19%) > bound to carbonates (2%) > exchangeable (1%). In contaminated soil samples, the content of Cu in the first two fractions--exchangeable (from 1 to 2%) and carbonate fractions--increases (from 2 to 3%). This is related to the presence of dispersed carbonates with a high specific surface area in the upper layer of humus horizon of Haplic Chernozem. Organic matter is the main component that retains Cu coming into the soil from anthropogenic sources (up to 40%). The active interaction of Cu with organic matter leads to a sharp increase in the metal compounds formed with this component. With increasing pollution, Cu accumulates in the composition of components of soil origin. Therefore, the relative content of Cu in the primary minerals decreases (from 51% to 39%). It can serve as a diagnostic indicator in determining the level of anthropogenic load on the soil. [ABSTRACT FROM AUTHOR]

The uncertainty of methods for determining the heavy metal compounds, as well as problems in the comparison of the methods used, require further studies in this field. The aim of research is to study the fractional composition of Cu and Zn compounds in soil under model contamination conditions using different fractional methods. Chernozem Haplic was artificially contaminated with Cu and Zn acetates at rate of 300 mg kg -1. Distribution of Cu forms in soil at the use of sequential fractionation by the Miller method modified by Berti and Jacobs (1996) and the Tessier method (Tessier et al. 1979) are revealed. General regularities in the distribution of Zn and Cu compounds in unpolluted and polluted soils have been established by two sequential fractionation methods. The content of Cu, Zn in the first two most mobile fractions is low. In uncontaminated soil exchangeable and bound to carbonates metals are 3-4% and are represented mainly by the compounds of the metals held by the carbonates. A significant increase in the exchangeable fraction of Cu amounted to 2 times (from 0,5-1% of the sum of fractions in uncontaminated soil to 1-2% in contaminated soil) and of Zn to 3-4 times (from 1% to 3-4%). The contaminated soil is characterized by accumulation of Cu and Zn in fractions associated with Fe-Mn oxides and organic matter. The role of organic matter in Cu accumulation is highest (up to 28-36%). Zn is characterized by affinity to Fe-Mn oxides (up to 26-39%). The differences of Cu and Zn compounds are related to the metal affinity for soil phases, as well as to the selectivity and extraction capacity of the reagents used in methods. The Miller method allows better tracing the heavy metal fractions loosely bound to the soil because of the use of weaker extractants with high complexing capacity, which hampers the reprecipitation of metals from the extract. The Tessier method is more suitable for the separation of the total anthropogenic component from contaminated soils. This is related to the higher extraction capacity of reagents used in the Tessier method. [ABSTRACT FROM AUTHOR]

Dust is one of the major hazards that affect workers in the mining industry. Currently, there are many technologies that help reduce the dust load on the miners. But looking at the statistics of professional and profession-related diseases, it can be seen that the incidence of diseases caused by various industrial aerosols is not reduced. This indicates that the existing methods are not sufficiently effective. It is not excluded that the very method of estimating the dust load on workers is not correct and needs to be improved. A new method of estimating dust load, which takes into account the climatic factors in the workplace, seasonal variation and energy expenditures of workers and fractional composition of dust, was developed. [ABSTRACT FROM AUTHOR]