Migration Of Substances Research Articles

Approaches for predicting the soil-water characteristic curves of compacted quartz sand based on particle packing theory

The soil-water characteristic curve (SWCC) is an important basis for describing hydraulic properties, which is closely related to environmental problems such as the migration of toxic substances from groundwater and soil. The SWCC models vary considerably with respect to the void ratio or bulk density. However, the void ratio and bulk density of the same soil change at different depths or positions within a flat space. Accurate simulation or calculation requires a precise SWCC, but measuring every SWCC under each density or void ratio condition is difficult. In this study, two particle packing models, the Kwan model and the modified linear packing density model (MLPDM), were introduced into the van Genuchten (VG) model to predict the SWCC for soil at the minimum void ratio (the maximum dry density). Then, the prediction method of the SWCCs for the same soil with different densities or void ratios was given. A series of laboratory tests using quartz sand mixtures were conducted to verify the accuracy of two extended models (the K-VG model and the M-VG model). For the K-VG model, the average RMSE was 0.020. For the M-VG model, the average RMSE was 0.017. In general, the SWCCs predicted by the two extended models were consistent with the measured values.

Quantification of immiscible displacement in a rough-walled fracture through direct visualization

Subsurface substance migration in the fractured rock aquifer is mainly controlled by fractures, and immiscible fluid-fluid displacement in fractures is important to many geophysical processes and engineering activities. Using a fracture-visualization system, we present the qualitative and quantitative assessment of fracture geometry associated with fluid movement and distribution in the rough fracture. Based on fracture geometry and statistical analysis, we first conducted a quantitative study of fracture surface roughness and aperture distribution. Then, fractal dimensions of displacement front and residual oil distribution were determined by image processing procedures. Influenced by wettability and micro-scale roughness, at the end of the displacement, residual oil saturation of molded sample is lower (6.45%–25.74%), and displacement pattern is more uniform, indicating that displacement effect is better. Due to smaller differences in residual oil saturation (9.08%) under different injection directions, the impact of wettability on the displacement process is greater than that of anisotropic roughness. Additionally, the fractal dimension of the displacement front increased under low injection rates initially but decreased when the rate was increased later. Overall, visualized temporal monitoring of experimental images enabled us to provide a preliminary assessment of the impact of anisotropic roughness and the material constituting the fracture wall on invading fluid saturation and the fractal dimension of the displacement front under various injection rates.

Cellulose trays with PLA-based liners as single-used food packaging: Characterisation, performance and migration

In France, collective catering must adopt compostable alternatives for warming/serving trays to reduce the use of plastic materials by 2025. Cellulose trays laminated with biobased polymers such as polylactic acid are gaining popularity. To guarantee safety, the presence and the migration of substances should be tested according to established protocols. PLA, PCL, PBAT, PBS, PEG, were identified in the liners of the trays collected from the market. Testing ensured the compliance with global migration limit. After undergoing the real-condition processing, the trays experienced minor physical degradation and fractures, compromising integrity. Heating to higher temperatures (130 °C) led to some modifications of the polymer composition, and several substances linked to the safety of the trays were detected as potential migrants like plasticizers and additives (styrene and a volatile fluorinated compound) in some of the samples. Migration of monomers and oligomers from the liner should further be studied to guarantee food safety.

Development of a solid food simulant to evaluate migration of chemicals from paper and board food contact materials to moist food

Food contact materials (FCMs) i.e. materials that food is packaged or handled in, must be safe for their intended use. European FCM legislation uses a risk-based approach, with a cornerstone of FCM’s safety evaluation being measurement of migration of substances from FCMs to food simulants. The standard methods mainly developed for plastic FCMs are not always suitable for less inert and moisture sensitive materials such as paper and board. However, these are becoming increasingly common as FCMs e.g. to replace single-use plastics. In addition, there is a drive to further use recycled materials. To support this development, new methods for assessing the safety of these materials are needed. In the present feasibility study, a hydrogel crosslinked through freeze-thawing of poly(vinyl alcohol) was evaluated as a food simulant for moist foods. The migration of surrogate compounds from a spiked paperboard to the hydrogel was determined and compared to the migration to a real moist food (a slice of apple), the commonly used modified polyphenylene oxide (MPPO) and a water extract. Migration of polar surrogates to the hydrogel correlated well with the migration to the apple slice. However, our results indicate that the hydrogel is less suitable as simulant for non-polar surrogates. Overall, the study demonstrates the potential of this hydrogel-based simulant for improving risk assessment of less inert FCMs.

Influence of erosion control afforestation on some soil parameters in two watersheds in Southwest Bulgaria

Soil is limited resource with vital role in maintenance of variety ecosystems. One of the greatest treat for soils is soil erosion. This natural hazard is widely spread in the terrestrial world, and the territory of Bulgaria is also affected.  Important role for soil protection has a forest vegetation and afforestation is widely used for erosion control activity. The main benefits of afforestation are reduction of water runoff, erosion and sedimentation year-round, which is important for the areas located around the reservoirs and their basins. They also decrease the migration of vital substances for soils and sedimentation yield.  The main goal of the study is to establish the influence of erosion control afforestation to the main soil characteristics in the territory of two watershed situated in Southwest Bulgaria. Soil samples and dead leaf cover were analyzed as well as some characteristics of afforestation and topographic charac-teristics. It was established high water resistance of the soil aggregates under the planted forests and low resistance in the controls. The amounts of content of org. carbon and total nitrogen varying with slope and exposure. The differences between parameters of soils under afforestation and in control samples is established which shows an important influence of forest to the soil characteristics.

Численное моделирование миграции фильтрационных вод от объектов размещения твердых коммунальных отходов через грунтовые защитные сооружения

The paper studies numerically he processes of pollutant migration from the municipal solid waste (MSW) landfill and discusses the obtained results. Pollution of the natural environment with residues of substances and products resulting from the human household and industrial activities is one of the most urgent problems both in Russia and all over the world. In economically developed countries, in which waste management strategies are implemented to minimize garbage accumulation, priority is given to neutralization and recycling technologies, The beneficial effect of such strategy is a significant reduction of the waste volume. In Russia, despite the positive dynamics in the use of new waste management technologies, the main method of their treatment is disposal at MSW landfills. On the territory of Russia, along with the MSW landfills operated and built in accordance with environmental requirements, there are a large number of unauthorized landfills, which are of serious hazard to the environment. This raises the question of assessing the impact of such facilities on the environment. To study the characteristics of the pollutant distribution and determine the waste migration parameters, the archival data from a set of field and laboratory studies in the area of the existing MSW disposal site were used. A numerical model was constructed to describe the hydrodynamics of the migration of substances in the soil and soil layer forming the base of a solid waste disposal facility. The process of pollutant spreading is described in terms of dry residue. The model takes into account such factors as convective transport, diffusion and geological composition of the base of the waste disposal site, which have a significant impact on the pollutant migration.

Development of crosslinked gelatin films through Maillard reaction and reinforced with poly(vinyl alcohol) for active food packaging

In order to improve the functionality of natural gelatin films for active food packaging applications, a combined strategy of crosslinking via Maillard reaction and blending enhancement incorporated with poly(vinyl alcohol) (PVA) was explored. In this study, when the mass ratio of gelatin to glucose was 10:1, Maillard reaction of crosslinked gelatin films was the highest, UV absorption and browning index reached the maximum. Infrared analysis showed that PVA could form strong interfacial interactions with gelatin matrix. The presence of PVA could significantly improve the toughness, water absorption, transparency, and oxygen barrier properties of crosslinked gelatin films. When the amount of PVA reached 5 %, elongation at break and oxygen barrier properties of crosslinked gelatin films were improved by 76.7 % and 47.9 % compared with pure crosslinked gelatin film. Even when the amount of PVA reached 10 %, UV absorption (at 315 nm) of crosslinked gelatin films still exceeded 98.7 %. The addition of PVA could accelerate the dissolution and swelling of crosslinked gelatin films, promoting the migration and release of active substances (Maillard reaction products (MRPs)). The two antioxidant activities tests (DPPH and ABTS method) achieved the highest radical scavenging rates of 71.6 % and 91.2 %, respectively, with corresponding PVA addition of 5 % and 7.5 %. After continuing to add PVA, antioxidant activities began to significantly decrease, which was directly related to the decrease in the generation of MRPs. Therefore, crosslinked gelatin films reinforced with appropriate amount of PVA can be considerable potential as active films for renewable food packaging applications.

Analysis of Migrant Compounds from Food Packaging: Application to Disposable Tableware and Risk Analysis

Substance migration from nine types of disposable plates made from cardboard, polystyrene (PS), and polypropylene (PP) have been studied. Migration tests were performed in four food simulants over 10 days at 40°C. Simulant extracts were analyzed using SPME-GC-MS and UPLC-QTOF-MS to identify and (semi)quantify volatile and non-volatile migrants, respectively.

Deep dewatering of municipal sludge by combining alternating electric field electro-osmosis and nano-CaO2 oxidation

To improve the effect of traditional electroosmotic sludge dewatering, combining alternating electric field electro-osmosis and nano-calcium peroxide (CaO2) oxidation, a homemade vertical electro-osmosis dewatering device was employed in this work to study the effects of different parameter on the dewatering of primary dewatered sludge from municipal sewage treatment facilities with a moisture content of around 85%. The sludge water content (Wr) was used as an indicator, and concentration of extracellular polymeric substances (EPS) in the dewatered sludge was measured, and its structure was analyzed to investigate the effect of EPS changes on sludge dewatering.The response surface method was used to optimize the parameters. Wr decreased to 36.23 % at a CaO2 amount of 14.79 mg·g−1 dry sludge, a time ratio of 7.98:1, and a voltage gradient of 19.71 V·cm−1. Analysis of zeta potential and infrared characterization indicates that under acidic circumstances, CaO2 reacts more positively with water to produce hydrogen peroxide, and EPS is more easily destabilized and degraded, due to this, the problem of unequal water content in the cathode and anode sludge cakes is also solved. During the sludge dewatering process, the synergistic effect of alternating electric field and calcium peroxide together destroys the cell structure and EPS of sludge, especially the tightly bound EPS (TB-EPS), enabling the migration of substances and the formation of loosely bound EPS (LB-EPS), slime EPS (S-EPS), or filtrate, which can improve the sludge dewaterability.

A Comparative Study on the Migration of Substances from Microwavable Plastic Food Containers into Food by Microwave and Conventional Heating

A Comparative Study on the Migration of Substances from Microwavable Plastic Food Containers into Food by Microwave and Conventional Heating

Analysis of the substances migration within the trophic chain “soil — plant — raw meat materials”

The trophic chain, which manifests the correlation at nutritional level between various macro- and microorganisms, is an important factor of the ecosystem; it can show the migration of various substances within the chain “soil — water — plant — animals”. The trophic chain in Borgoy depression area was studied due to the profound correlation between the compositional characteristics of the soil and pronounced organoleptic features of meat of the sheep that feed on grass in this area. For the experiments, control and experimental samples of soil, water, plants and mutton meat were examined. The samples taken near the saline lake within the Borgoy depression on the west of Beloozersk village served as an experimental sample. The samples taken 30 km from the salt lake near Petropavlovsk village in the Republic of Buryatia served as control sample. Experiments have shown that the soil of the Borgoy depression is a saline soil, with a depth of the salt horizon of 0–30 cm, and the salt belongs to chloride-sulfate-soda type of salinity. It is noted that the saline soil is characterized by a much higher content of carbonates, chlorides and cations of sodium, potassium and magnesium. Correlation was found between the isotopic composition in soil, vegetation and the raw meat materials. More profound certain organoleptic features of Borgoy mutton were noted. It’s highly probable that this fact is associated with the peculiarities of the mineral, chemical, and amino acid compositions of meat of the livestock that lives in the pastures of the Borgoy depression, characterized by saline soils. Despite the increased content of heavy metals such as lead and copper in the soil, data on sheep muscle tissue showed that all values of toxic elements content are within the permissible concentration range. The transfer of heavy metals from the soil to the aboveground part of plants is hindered by the underground root part, which serves as barrier.

Наукове обґрунтування медико-санітарного нормативу у ґрунті нових стійких пестицидів – представників різних хімічних класів

The aim: scientific substantiation of the medical-sanitary regulations is the maximum permissible concentration in soil of modern persistent pesticides: amicarbazone from the class of triazolones, bicyclopyrone from the class of triketones and pydiflumetofen from the class of pyrazolecarboxamides. Materials and methods. Three stages of research were carried out: mathematical modeling of amicarbazone, bicyclopyrone and pydiflumetofen migration from soil to adjacent environments; laboratory hygienic experiment to examine studied substances behavior in systems «soil – plants», «soil - atmospheric air» and substantiation of their threshold concentrations in soil according to the translocation, air-migration and water-migration indicators of harmfulness; impact study of amicarbazone, bicyclopyrone and pydiflumetofen on the nitrifying activity of leached chernozem and setting their threshold concentrations according to the general sanitary indicator of harmfulness. Results. It was experimentally established that the threshold concentrations in soil according to the water-migration indicator of harmfulness are the concentrations of amicarbazone, bicyclopyrone and pydiflumetofen of 0.02 mg/kg, 0.01 mg/kg, and 0.06 mg/kg, respectively. The calculated threshold concentrations of amicarbazone (0.05 mg/kg), bicyclopyrone (0.02 mg/kg) and pydiflumetofen (0.05 mg/kg), which were obtained by mathematical modeling, turned out to be very close to experimentally determined ones, which proves a rather high prognostic ability of the applied calculation method. The threshold concentration in soil of amicarbazone, bicyclopyrone and pydiflumetofen according to the water-migration indicator of harmfulness turned out to be the lowest compared to the threshold concentrations according to the translocation (0.2 mg/kg, 0.25 mg/kg and 0.12 mg/kg, respectively), air-migration (0.05 mg/kg, 1.0 mg/kg and 1.2 mg/kg, respectively) and general sanitary (0.2 mg/kg, 0.05 mg/kg and in the range 0.12-0.6 mg/kg, respectively) indicators of harmfulness. Therefore, the leading link of studied substance migration in the environment is the «soil – groundwater» system. Conclusions. The MPC of amicarbazone, bicyclopyrone and pydiflumetofen in soil is scientifically justified at the level of 0.02 mg/kg, 0.01 mg/kg and 0.06 mg/kg, respectively, according to the limiting water-migration indicator of harmfulness. Based on the studied substances in the recommended consumption rates and frequency of treatments the usage of plant protection products in the cultivation of agricultural crops will not lead to dangerous to human health contamination of groundwater, agricultural raw materials and atmospheric air, it will not cause a violation of the processes of self-cleaning of soil from nitrogen-containing organic substances in real soil-climatic conditions in Ukraine.

Effect of electrolytic zero-valent iron activated sodium hypochlorite on sludge dewatering performance.

Using electrolytic zero-valent iron-activated sodium hypochlorite (EZVI-NaClO) to pretreat sludge, the capillary suction time (CST) was utilized to evaluate sludge dewaterability. Ammonia nitrogen (NH4-N), dissolved phosphorus, and total phosphorus in the supernatant were used to analyze sludge disintegration. This approach aimed to evaluate the effectiveness of the pretreatment process and its impact on the sludge composition. The migration and transformation of extracellular polymeric substances (EPS), including dissolved EPS (S-EPS), loosely boundEPS, and tightly bound-EPS (TB-EPS), were analyzed by detecting protein and polysaccharide concentrations and three-dimensional fluorescence excitation-emission spectroscopy (3D-EEM). The sludge particle properties, including sludge viscosity and particle size, were also analyzed. The results suggested that the optimal pH value, NaClO dosage, current, and reaction time were 2, 100 mg/gDS (dry sludge), 0.2A, and 30 min, respectively, with a CST reduction of 43%. Protein and polysaccharide contents in TB-EPS were significantly reduced in the EZVI-NaClO group. Conversely, protein and polysaccharides contents in S-EPS increased, suggesting that EZVI-NaClO treatment could disrupt the EPS. Besides, the viscosity of the treated sludge decreased from 195.4 to 54.9 mPa·S, indicating that sludge fluidity became better. ZEVI-NaClO could enhance sludge dewaterability by destructing protein and polysaccharide structure and improving sludge hydrophobicity.

Can Geometric Parameters Enable Direct Prediction of Non‐Fickian Transport in Rock Fractures Across Diverse Flow Regimes?

AbstractAnomalous solute migrations in fractured rocks are governed by geometric characteristics and flow regimes. Although existing inverse models can describe this behavior, the underlying physics for quantifying key transport coefficients remains largely unexplored. Here, we investigate the quantitative impacts of geometric heterogeneity and flow regimes on solute transport in rock fractures. We conduct numerical experiments to simulate water flow and conservative solute transport in 3D fractures with varying geometric features and Reynolds numbers. Our results show that the non‐Fickian transport is prevalent across the entire flow regime, with Darcy flows attributed to geometric heterogeneity and non‐Darcian flows influenced by additional eddy zones. We employ the mobile‐immobile (MIM) domain model and continuous time random walk (CTRW) model to inversely model simulated breakthrough curves. Inverse analyses demonstrate that both models effectively characterize anomalous transport behaviors. The fitted transport coefficients of the MIM model exhibit stronger quantitative relationships with aperture and roughness parameters, as well as Reynolds number, compared to the CTRW model. By incorporating parameterized transport coefficients, we propose physics‐ and statistics‐based models to directly predict anomalous transport behaviors under different flow regimes. These prediction models accurately reproduce solute transport processes of all simulated cases with acceptable errors. The feasibility of directly predicting solute transport under varying flow regimes using geometric information is thus validated. Our study not only supports the study of substance migration based on geometric structure features, but also serves as a foundation for investigating geological activities based on substance migration information.

Migration of Nutrient Substances and Characteristic Changes of Chicken White Soup Emulsion from Chicken Skeleton during Cooking

The protein and fat in chicken skeleton can be emulsified in a boiling state to form milky white chicken soup. White chicken soup has a delicious taste, good nutritional value, a beautiful color, and volatile flavor compounds. However, cooking time significantly impacts the quality of white chicken soup. Herein, we investigated the influence of cooking time (30, 60, 90, 120, 150, 180, and 210 min) on the migration of nutrient substances and characteristics changes in white chicken soup from chicken skeletons. The results showed that nutrients such as total lipids, water-soluble protein, total sugars, solid matter, and oligopeptides in the chicken skeletons’ tissue continuously migrated into the soup during the cooking process. The total nutrient content in the chicken soup was highest after cooking for 180 min. Simultaneously, the white chicken soup obtained after cooking for 180 min had low interfacial tension and high whiteness, viscosity, and storage stability. The high stability index was associated with increased ζ potential and decreased particle size. The contact angle analysis results also indicated that the stability of the white chicken soup was improved when the cooking time reached 180 min. This research provides basic information for the production of high-quality white chicken soup.

Basic Study on Applicability to Artificial Barriers for Radioactive Waste Disposal Facility for Various Zeolites

Artificial barriers are being considered for the burial disposal of low-level radioactive waste in Japan. The artificial barrier consists of i) a low permeable layer made of bentonite materials that suppresses migration of nuclides due to advection, and ii) a low diffusion layer that uses cementitious materials that suppresses migration of nuclides due to diffusion. In addition, as methods of disposing of radioactive waste generated by the accident at the Fukushima Daiichi Nuclear Power Station, controlled disposal and isolation-type disposal are being considered. We thought that it would be effective to add adsorption performance to the performance of suppressing migration of such radioactive substances. In this study, we designed and experimented on the adsorption performance of mortar mixed with various zeolites, which had never been examined. As evaluation methods, i) fluidity, ii) strength, iii) low diffusivity, and iv) distribution coefficient of cesium and iodine were obtained. Based on the results, we reexamined the composition and conducted experiments to examine the applicability to high-adsorption artificial barriers. As a result, it was confirmed that the mass transfer resistance tends to be low due to the zeolite being porous. It was also shown that the strength of mortar mixed with zeolite depends on the cement matrix. As a result of this research, the distribution coefficient of cesium in cementitious materials using zeolite with a high cation exchange capacity designed in this research is higher than that of cementitious materials for low-level radioactive waste disposal facilities currently in operation 1,500 times was obtained. On the other hand, we were able to discover the possibility of examining construction on a full-scale regarding fluidity and compressive strength. As a future task, it was found that it is necessary to investigate a more practical artificial barrier by increasing the strength and densification of the cement paste.

Agro-ecological processes under conditions of biogeochemical imbalance of molybdenum in agrolandscapes of the Forest-Step zone

A special place in the theory and practice of landscape geochemistry belongs to biogeochemical zoning. Biogenic migration of substances and chemical elements can rightfully be considered one of the criteria for the typological classification of geochemical landscapes, which is the basis for building a map of geochemical landscapes of Ukraine. The scientific result of zoning is the recognition of spatial boundaries and areas of the territory consisting of connected components with uniform conditions of geochemical migration of chemical elements. With a long-term violation of the ratio between microelements, various diseases appear, which are called endemic, and the phenomenon itself — biogeochemical endemics. The latter most often occur due to a lack or excess of some threshold value of the concentration of microelements or a violation of the ratio of other micro­elements associated with it. On the basis of landscape-geochemical analysis and zoning, the authors defined the territory of the biogeochemical provinces of the Forest Steppe, where a lack of molybdenum content in the soil for normal plant development was found. In addition, the features of the molybdenum province are determined by low biogenic accumulation and intensive physicochemical dispersion of essential trace elements, increased mobility of most toxic trace elements in natural waters, and the absence of conditions for the formation of barriers of hydroamphoteric elements, including Mo2+. Also, in the territories of biogeochemical provinces, there is a high probability of the development of certain endemic phytopathologies and microelement diseases due to the imbalance of biogeochemical food chains.

Effect of using cassava and glycerol as food storage on the quality of bioplastic packaged food

Food packaging today often involves the migration of monomer substances from petroleum-based plastics into the food. This study aimed to determine the effects of storing food in bioplastic on moisture content and peroxide levels. The study design employed a post-test experimental design with a control group. Dodol samples were selected for this study using a simple random sampling method. The bioplastics used were made from cassava peel starch, and the food storage conditions included temperature-humidity variations of 10-15°C and 85.3-90.8% relative humidity and 25-29°C and 46.5%-80.4% relative humidity. Data were collected through laboratory tests and analyzed using the SPSS program. The study found a significant effect of glycerol dosage on the thickness of the bioplastic (p-value < 0.001). There was a significant influence of temperature-humidity storage on moisture content with glycerol dosages of 3 ml (p-value = 0.002), 4 ml (p-value < 0.023), and 5 ml (p-value = 0.007), as well as on the peroxide content of dodol. This effect was particularly pronounced with glycerol dosages of 3 ml (p-value = 0.001), 4 ml (p-value < 0.001), and 5 ml (p-value = 0.008). The results indicate that cassava peel starch bioplastic can serve as a viable alternative for food packaging, provided that temperature and humidity conditions during food storage are carefully controlled.

The Effects of Aniline-Promoted Electron Shuttle-Mediated Goethite Reduction by Shewanella oneidensis MR-1 and theDegradation of Aniline

The biological reduction of Fe (III) is common in underground environments. This process not only affects the biogeochemical cycle of iron but also influences the migration and transformation of pollutants. Humic substances are considered effective strategies for improving the migration and transformation of toxic substances and enhancing the bioavailability of Fe (III). In this study, the electron shuttle anthraquinone-2-sulfonate (AQS) significantly promoted the bio-reduction of Fe (III). On this basis, different concentrations of aniline were added. The research results indicate that at an aniline concentration of 3 μM, the production of Fe (II) in the reaction system was 2.51 times higher compared to the microbial reaction group alone. Furthermore, the degradation of aniline was most effective in this group. The increased consumption of sodium lactate suggests that aniline, under the mediation of AQS, promoted the metabolism of Shewanella oneidensis MR-1 cells and facilitated the involvement of more electrons in the reduction process. After the reaction, the solid mineral Fe (II)-O content increased to 41.32%. This study provides insights into the reduction mechanism of Fe (III) in the complex environment of microorganisms, iron minerals, electron shuttles, and pollutants. It aims to offer a theoretical basis for the biodegradation of aromatic hydrocarbon pollutants.

FORMATION OF THE COMPOSITION OF TRACE ELEMENTS OF SNOW DUST IN TYUMEN AND TOBOLSK USING HIERARCHICAL CLUSTER ANALYSIS

Link for citation: Zakharchenko A.V., Pasko O.A., Tigeev A.A. Formation of the composition of trace elements of snow dust in Tyumen and Tobolsk using hierarchical cluster analysis. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 8, рр. 110-120. In Rus. The relevance: search for new methodological approaches and techniques for assessing the aerosol migration of substances and characterizing air pollution. The purpose of the work is a comparative analysis of clusters of the content of microelements of the solid phase of snow in the closely located cities of Tyumen and Tobolsk with respect to clean background and areas subject to technogenic impact. The materials: the trace elements of solid phase of the snow cover. The methods: chemical-analytical for determining the content of trace elements, hierarchical cluster in the analysis of geochemical spectra, probabilistic-statistical. Results. The background dust load in Tobolsk is less, and the inner city load is higher compared to Tyumen. A cluster data structure of 8 clusters has been established with the allocation of two large groups that combine the Tobolsk and Tyumen sites, which are divided into clusters with low and high content of trace elements. Conclusions. The conditionally background cluster C6 is present in Tobolsk (22,6 %) and Tyumen (11,7 %), and C5 – 13 % in Tobolsk and 8 % in Tyumen. A specific Tobolsk cluster C8 with a predominance of scattered elements (48 %) was found at 2 sites in Tyumen, which may indicate a possible transfer of aerosols between these cities. Some technogenic clusters contained heavy metals, while others were dominated by Sc, Cr, Ni, Zn, and Cd. Technogenic clusters (C7, C1) differ in the shape of the geochemical spectrum: heavy metals predominate in some, trace elements (C8) predominate in others; the same applies to conditionally background samples. The specific technogenic Tyumen cluster C4 is distinguished by high values of Cu and Mo. Conditionally isolated background clusters had a low content of microelements. To identify environmental conditions, we moved from the standardized values of cluster analysis to their material content. It is shown that some clusters contain heavy metals, while others contain Sc, Cr, Ni, Zn, and Cd. Conditionally isolated background clusters had a low content of microelements. Using the content of microelements of the C5 cluster as a background, the environmental index of pollution Zc was calculated, which in Tobolsk reaches a high and dangerous level of pollution 60,8–83,7, in Tyumen – an average, moderately dangerous level Zc (32–64). The use of cluster analysis makes it possible to determine the trace elements pollution of snow dust and the territory as a whole.