Ecological risks caused by toxic elements impact on ambient air determined in the study of the snow cover in Tomsk GRESc2 area

The relevance of the research is caused by the need of sustainable development of coal power. One of components to achieve this sustainability is the predictive assessment of the impact of solid emissions resulting from coal combustion, in transition of raw materials into digestible form, on the health of population in terms of increasing the share of coal generation in the fuel sector. The main aim of the research is to determine the level of air pollution with solid emissions from thermal energy (Tomsk GRES-2), and to define the value of inhalation health risk based on the study of the snow cover. Objects. To assess the environmental health risks on the territory of Tomsk the authors have selected the areas corresponding to the regions with the highest influx of anthropogenic dust particles in the impact zone of Tomsk GRES-2, as well as the area outside the impact zone of Tomsk GRES-2, to compare the results of the study. Methods: atmogeochemical; risk assessment methods of chemical substances on human health; method for recovery of elemental concentrations in ambient air on the basis of their content in solid phase of snow cover; analysis of uncertainties in calculation of average daily doses using a random sampling of values with a certain distribution laws of the consider values. Results. On the territory influenced by the GRES-2 the authors determined a high level of accumulation of Zn, Ba, W, Ni, V, Cu, Co in solid residue of snow relative to the background site that reflects the specificity of the effect of emissions of the considered power plant on the air. The greatest specific contribution to the integral level, non-cancer risks from chronic inhalation exposure of metals in the vicinity of the GRES-2 make Cu, Al, Mn, Ba and Zn. For all elements with carcinogenic properties, with the exception of Cr (VI), the values of the individual cancer risk is below 10-6, which corresponds to a negligibly small level of risk. Individual carcinogenic risk caused by inhalation of Cr (VI) has values in the range from 7,65×10-7 to 4,6×10-5, and the values corresponding the upper boundary are considered according to the common methodology as a valid risk. The levels of risk from inhalation exposure of chemical elements in the zones of influence of Tomsk GRES-2, as well as the values of individual carcinogenic risk are acceptable.