Maximum Permissible Concentration Research Articles

MACRO- AND MICROELEMENT COMPOSITION OF THE HERB AND ROOTS OF HAPLOPHYLLUM DAURICUM (L.) G. DON.

Haplophyllum dauricum is a rich source of lignans with antitumor activity. It has been actively used in the practice of Traditional medicine. In addition to lignans, the chemical composition of the species is represented by coumarins, flavonoids, alkaloids and essential oils. However, the composition of the elements of the species, which are necessary for the development of quality criteria of medicinal plants, has not been studied before. In this regard, the purpose of the work was to study the content of macro- and microelements in the aboveground and underground parts of Haplophyllum dauricum of the flora of Buryatia and Transbaikal territory. The content of the following elements was determined by inductively coupled plasma atomic emission spectrometry: Li, Be, Na, Mg, Al, P, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Zr, Mo, Cd, Sb, Te, Ba and Pb. The content of Hg was determined by the "cold steam" method using an atomic absorption analyzer. According to the obtained data, Haplophyllum dauricum is a rich source of calcium, potassium, magnesium and phosphorus, which were dominant. Among the microelements, iron and titanium were in highest concentration, which were accumulated mainly in the underground part of the plant. The content of heavy metals did not exceed the maximum permissible concentration established by the State Pharmacopoeia of the Russian Federation.

RADIATION AND ECOLOGICAL STUDIES OF VEGETATION OF LUTSK DISTRICT OF VOLYN REGION

Abstract. The content of radionuclides of 137Сs, 90Sr and heavy metals in vegetation and agricultural products was found out in the settlements of Lutsk district of Volyn region. The results of our own field expeditionary research, as well as the results of generalization of stock materials of the Laboratory of Ecological Land Safety and Product Quality of the Volyn branch of the state institution “Institute for Soil Protection of Ukraine” (Lutsk) are the basis of the research. The plant products contain a small content of radioactive elements in the settlements of the Lutsk district of the Volyn region. The greatest pollution of plant products was found in the settlements of Sytnytsia and Omelіano. The content of the 137Сs, 90Sr does not exceed the maximum permissible concentrations. Exceeding the maximum permissible concentrations for the content of heavy metal salts was found in potatoes in the villages of Pozharky, Vesele. The results of the radiation-ecological study can be taken into account for the optimization of nature management and are necessary for state emergency management bodies of natural-technogenic content, for the possibility of reasonable planning and effective implementation of measures and projects for strengthening ecoenvironmental safety. The data obtained are important for the development of the National Concept to overcome the consequences of the Chernobyl disaster on the contamination of agricultural products with radionuclides and heavy metals.

Trend in indices of public health risk caused by air pollution in an industrial center

Introduction. In industrialized regions and cities, atmospheric air pollution greatly contributes to the hazard for public health. The study aim was to assess the state of the atmospheric air in the city of Novokuznetsk over 2017–2022 and determine the levels of risks to public health. Materials and methods. Data on gross atmospheric emissions and average annual concentrations of the substances was taken from the reports on the state of the environment of the Kemerovo region and Novokuznetsk. Maximum permissible concentrations of atmospheric pollutants were determined according to SanPiN 1.2.3685–21. Calculations of the risks to public health were carried out in accordance with Guideline P 2.1.10.1920–04. The classification of risk levels was carried out on the basis of MR 2.1.10.0156–19. 2.1.10. Results. Decrease in total atmospheric emissions from 2017 to 2022 amounted to 50.1 thousand tons (about 16%). At the same time, there was revealed an excess of the average annual maximum permissible concentrations of benzo(a)pyrene (3.5-11.2 times); formaldehyde (1.7 and 3.4 times over 2021 and 2022, respectively); suspended substances (1.6 and 2.0 times in 2021 and 2022, respectively); hydrogen fluoride (1.2 times in 2021); nitrogen dioxide (1.6 times in 2022). The hazard coefficients of benzo(a)pyrene were 3.5–11.2 (high level of non-carcinogenic risk); formaldehyde and suspended substances – 1.1–3.0 (alarming level). In 2022, the hazard coefficient for formaldehyde was 3.4 (high risk level), suspended substances – 2.0, nitrogen dioxide – 1.6 (alarming risk level). Hazard indices of pollutants were detected in the range from 7.0 to 20.1 (high level of risk). The main critical organs and systems were the immune system (hazard indices were 4.0–14.6), development during childhood (hazard indices – 3.5–11.2), respiratory organs (hazard indices – 3.0–8.6). These risk levels range from alarming to high. The highest total individual carcinogenic risk (1.6•10–4) was determined in 2021 (alarming level), the main contribution is made by formaldehyde. Limitations. In 2022, there were no data on carbon (soot) concentrations, so the level of total carcinogenic risk this year cannot be considered to be correct. Conclusion. Reducing the total volume of atmospheric emissions does not provide a significant effect on improving the environmental situation and public health, since high concentrations of pollutants remain in the city’s atmosphere. When implementing air protection measures, it is necessary to take into account risk criteria.

Assessing health risks in bottled water: chemical compounds and their impact on human health.

Bottled mineral and spring water constitute one of the main sources of drinking water. Relevant legal acts in each country individually regulate the highest permitted concentrations of harmful substances in these waters. However, current regulations do not take into account newly emerging contaminants such as BPA. Analysis of the chemical composition of 72 bottled waters from the Polish market showed that undesirable elements occur in quantities that do not exceed the maximum permissible concentrations. Special attention should be paid to bottled therapeutic water, which may contain elevated concentrations of some micronutrients, such as Al, B, Ba, Fe, Mn, or Sr contributing to the pattern of health risk with excessive consumption of this type of water. The presence of BPA was confirmed in 25 tested waters. The calculated hazard index values showed that the most exposed group are children up to 12 years of age. The greatest attention should be paid to waters with high mineralisation, for which the calculated risk values are the highest.

Assessment of parent and alkyl -PAHs in surface sediments of Iranian mangroves on the northern coast of the Persian Gulf: Spatial accumulation distribution, influence factors, and ecotoxicological risks

Spatial patterns, potential origins, and ecotoxicological risk of alkylated (APAH) –and parent –(PPAH) polycyclic aromatic hydrocarbons (PAHs) were studied in mangrove surface sediments along the northern coasts of the Persian Gulf, Iran. The mean total concentrations (ngg−1dw) ∑32PAH, ∑PPAHs and ∑APAHs in sediments were 3482 (1689–61228), 2642 (1109–4849), and 840 (478–1273), respectively. The spatial variability was similar among these PAH groups, with the highest levels occurring in Nayband National Marine Park (NNMP). Physicochemical environmental factors, such as sediment grain size, and total organic carbon (TOC) contents, are significant factors of PAH distribution. These findings suggest that PAH pollution level is moderate-to-high, supporting the current view that mangrove ecosystems are under intensive anthropogenic impacts, such as petrochemical, oil and gas loads, port activities, and urbanization. Non-parametric multidimensional scaling (NPMDS) ordination demonstrated that NNMP mangrove is the critical site exhibiting high loading of PAH pollutants. Here, for the first time in this region, Soil quality guidelines (SQGs), Toxic equivalency quotient (TEQ), Mutagenic equivalency quotient (MEQ), and composition indices comprising Mean maximum permissible concentration quotient (m-MPC-Q), and Mean effect range median quotient (m-ERM-Q) methods were used to have a comprehensive risk assessment for PAH compounds and confirmed medium-to-high ecological risks of PAHs in the study area, particularly in the western part of the Gulf, highlighting the industrial impacts on the environment.

Sustainable carbon sequestration via olivine based ocean alkalinity enhancement in the east and South China Sea: Adhering to environmental norms for nickel and chromium

Enhancing silicate weathering to increase oceanic alkalinity, thereby facilitating the absorption of atmospheric carbon dioxide (CO2), is considered a highly promising technique for carbon sequestration. This study aims to evaluate the feasibility and potential of olivine-based ocean alkalinity enhancement (OAE) for the removal of atmospheric CO2 and its storage in seawater as bicarbonates in the East and South China Seas (ESCS). A particular focus is placed on the potential ecological impacts arising from the release of nickel (Ni) and chromium (Cr) during the olivine weathering process. We considered two extreme scenarios: one where Ni and Cr are entirely retained in seawater, and another where they are completely deposited in sediments. These scenarios respectively represent the maximum permissible concentrations of Ni and Cr in seawater and sediments during the OAE process. Current marine environmental quality standards (EQS) were utilized as the threshold limits for Ni and Cr in both seawater and sediment, with concentrations exceeding these EQS potentially leading to significant adverse effects on marine life. When all released Ni is retained in seawater, the allowable dosage of olivine varies from 0.05 to 13.7 kg/m2 (depending on olivine particle size, temperature, and water depth); when all released Ni is captured by sediment, the permissible addition of olivine ranges from 0.21 to 2.1 kg/m2 (depending on mixing depth). Given the low solubility of Cr, it is not necessary to consider the scenario where Cr exceeds the limit in seawater. The allowable amount of Cr entirely retained in sediments ranges from 0.69 to 47.2 kg/m2.In most scenarios, the accumulation of metals in sediments preferentially exceeds the corresponding threshold value rather than remaining in seawater. Therefore, we recommend using alkalization equipment to fully dissolve olivine before discharging into the sea, enabling a larger-scale application of olivine without significant negative ecological impacts.

WASTEWATER TREATMENT OF COAL TAR PROCESSING PROCESS FROM PHENOL

The coal tar processing process provides the chemical industry with valuable products: naphthalene, cresol, xylenols, phenol, technical oils and lubricants. The most significant product of coal tar processing is anthracene, which is a raw material for the production of carbon black. The prospects for the implementation of the coal tar processing process entail a danger to the environment and public health.Wastewater formed during the processing process has a complex chemical composition, mainly represented by organic aromatic compounds. Wastewater pollutants significantly exceed discharge standards permissible for discharge into the Centralized Wastewater Disposal System of Settlements and Urban Districts. Phenol, which has the third hazard class according to the standards of maximum permissible concentrations of harmful substances in the waters of water bodies of fishery importance, is particularly dangerous. The toxic effect of phenol leads to the suppression of biocenoses, a decrease in the number of living organisms, negatively affects human health, and can lead to death. Based on the above, in order to reduce the anthropogenic load on the environment and maintain the quality of water resources, it is necessary to carry out a set of environmental measures aimed at wastewater treatment.The article presents methods of wastewater purification from phenol, describes complex purification methods and formulates proposals for the technology of wastewater treatment of the enterprise. Spectral and quantitative chemical analysis were performed to determine the composition of wastewater. Regenerative cleaning methods are proposed. Methods for wastewater treatment have been formulated and implemented. Methods for wastewater treatment of the coal tar processing process are proposed.The aims of research are to reduce the concentration of phenol in wastewater to the standard values permissible for discharge into the Centralized Wastewater Disposal System of Settlements and Urban Districts, based on experimental data; formulate a proposal for the wastewater treatment of the coal tar processing process from phenol.Objectives of the work are to study the composition of the source wastewater; to consider methods of wastewater treatment from phenols; to carry out wastewater treatment, based on the results of the study, to propose a wastewater treatment scheme.The object of the study is the wastewater of the enterprise after the coal tar processing process.

In vitro and in vivo screening of bacterial species from contaminated soil for heavy metal biotransformation activity

Heavy metals (HMs) are widely used in various industries. High concentrations of HMs can be severely toxic to plants, animals and humans. Microorganism-based bioremediation has shown significant potential in degrading and detoxifying specific HM contaminants. In this study, we cultivated a range of bacterial strains in liquid and solid nutrient medium containing different concentrations of different HMs to select and analyze bacteria capable of transforming HMs. The bacterial strains most resistant to selected HMs and exhibiting the ability to remove HMs from contaminated soils were identified. Then, the bacterial species capable of utilizing HMs in soil model experiments were selected, and their ability to transform HMs was evaluated. This study has also generated preliminary findings on the use of plants for further removal of HMs from soil after microbial bioremediation. Alcaligenes faecalis, Delftia tsuruhatensis and Stenotrophomonas sp. were selected for their ability to grow in and utilize HM ions at the maximum permissible concentration (MPC) and two times the MPC. Lysinibacillus fusiformis (local microflora) can be used as a universal biotransformation tool for many HM ions. Brevibacillus parabrevis has potential for the removal of lead ions, and Brevibacillus reuszeri and Bacillus safensis have potential for the removal of arsenic ions from the environment. The bacterial species have been selected for bioremediation to remove heavy metal ions from the environment.

INFORMATION SUPPORT IN ENVIRONMENTAL PROTECTION TECHNOLOGIES

The information support in environmental protection technologies includes forecasting and information analysis. The informational component is a necessary tool for assessing the level of environmental impact of the activities of industrial enterprises, with the aim of applying the necessary methods and means of protection. In this study, the information support for a metallurgical enterprise is considered, which is based on forecasting the level of atmospheric air pollution by gas emissions of the enterprise. The analysis of the concentration fields makes it possible to single out the areas of the city that fall into the zone of influence of pollutants depending on the direction and speed of the wind, to compare them with the maximum permissible concentration. The informational component regarding the enterprise's impact on the environment is important for the enterprise itself, from the point of view of adjusting its activities regarding environmental safety. At the same time, the information support is important for people who live directly outside the sanitary zone, but are exposed to harmful factors that spread in the environment according to the state of the atmosphere.

Heavy metal content of mountainous agricultural soils and ecological risk assessment in Gadabay district, Azerbaijan

Objective: The objective of this study was to i) investigate the distribution characteristics of heavy metals, ii) examine their relationships with basic soil properties, and iii) characterize their potential sources and ecological risks. Material and Methods: A total of 85 samples were collected from the surface horizon (0-15 cm) of Chernozem soil in a representative agricultural area located in the Lesser Caucasus Mountains (Gadabay district), and heavy metal contents and basic soil properties were determined. Results: The mean of the heavy metals followed a decreasing order: Mn>Zn>Cu>Cr>Ni>Co>Pb>As>Se>Cd and some heavy metals (As, Cd, Se) exhibited a fragmented distribution. Co, Cr, Mn, Se and Zn contents were higher than the background concentration, while others (As, Cd, Co, Cu, Pb and Zn) exceeded the maximum permissible concentration. Conclusion: The spatial distribution of heavy metals was characterized by their typical and element-specific distribution. The noted variability was likely related to geologic features (soil mineralogy), mining history and agricultural practices. Notably, the presence of limestone and clay minerals contributed to the association of Cd, Cu and Se and Mn and Pb, respectively. Sand content influenced the mobility of Cr and Cu. The relations between pH and Cr, Ni and Se was the indication of the influence of the parent material on the distribution of these metals.

Assessment of the biological effect of natural silicon when entering the body of experimental animals with drinking water. Part 1

Introduction. The biological effect of natural silicon (Si) and its hygienic regulation in drinking water still remain subjects of controversy in the scientific literature and in the practice of providing favourable conditions for water use by the population. In this regard, an assessment was made of the effect of natural silicon contained in drinking water in concentrations close to the maximum permissible concentration on the body of laboratory animals.
 Materials and methods. Drinking waters containing natural Si at MPC levels in water were studied, their effect was assessed in a three-month experiment on 80 white outbred male rats. Observations were made of the general condition, appearance of the animals, body weight dynamics, water consumption. 
 The morphological composition of whole blood was studied. Biochemical indices of the condition of internal organs, including the liver, were determined 
 in serum samples (the ALT and AST activity, the level of total protein and albumin), pancreas (α-amylase activity), kidneys (creatinine content), as well as lactate dehydrogenase activity as a nonspecific indicator of tissue damage.
 Results. In animals received 17±3.4 mg/L silicon with drinking water at a hardness of 2.25±0.47 mg-eq/L, a significant decrease in ALT activity was found on the 30th and 90th days of the experiment, AST – on 90th day, increase in the content of total protein and albumin in the serum on the 30th day of the experiment. Drinking water with silicon concentrations of 20.5±4.1 mg/L and hardness 3.55±0.76 mg-eq/L decreased ALT activity and serum creatinine concentration on the 30th day and increased amylase activity on the 90th day of the experiment. The animals had the highest water consumption and intake of silicon from drinking water over the first month of the experiment.
 Limitations. Limitations of the study are related to the short duration of observation and the small number of points for determining biochemical parameters over time.
 Conclusion. Consumption of drinking water containing natural silicon for 90 days led to changes in biochemical indices, largely indicating the positive effect of the element in concentrations of 17±3.4 mg/L and 20.5±4.1 mg/L on the body of laboratory animals.

GEOCHEMICAL AND SANITARY-CHEMICAL CHARACTERISTICS OF WATER SPRINGS OF BOGORODSKY AND LOSIN-PETROVSKY DISTRICTS OF THE MOSCOW REGION

This paper is the results of evaluated of water parameters (COD, pH, electrical conductivity), the content of major ions (Ca2+, Mg2+, Na+, K+, NH4 +, HCO3–, Cl–, SO4 2–, NO3 –) and microelements (Co, Ni, Cu, Zn, Cd, Pb, Sr, Ba, Mn) for 12 springs in the Bogorodsky and Losino-Petrovsky districts of the Moscow region. The waters are slightly acidic-near-neutral (pH 5.5–7.5) with the mineralization from 0.07 to 0.5 g/l, the total hardness is 0.63–5.7 mg- eq/l, the composition of the water is variable. Spring waters are divided into four groups: Cl-SO4-HCO3-(Mg)-Ca; (SO4)-HCO3-Cl-Na-Ca; (Cl)-HCO3-Ca; and mixed composition. Based on the thermodynamic calculation using the Visual-MINTEQ, it was found that the predominant dissolved forms of Ba, Sr, Mn, Zn, Cd, Ni, Co in the waters in the waters of the surveyed springs are free ions. For Cu and Pb, the factors for the formation of migration forms are the predominant anions of water, as well as the presence of organic matter in water. COD values and nitrogen compaund in the waters of individual springs are indicate that the formation of the composition of spring waters is associated with the infiltration of atmospheric precipitation through the modern sediments subject to antropogenic press. The values of other sanitary-chemical indicators (mineralization, pH, total hardness, chlorides, sulfates, mag- nesium, sodium, manganese), the content of standardized microelements are lower than their maximum permissible concentrations in drinking water.

DEVELOPMENT OF A MATHEMATICAL MODEL FOR ANALYSING THE HAZARDOUS IMPACT ON THE STATE OF GROUNDWATER IN CITY AGGLOMERATIONS FROM MISSILE AND ARTILLERY ATTACKS

The authors have developed a mathematical model for analysing the hazardous impact on the groundwater in urban agglomerations from missile and artillery attacks. The mathematical model consists of a system of four analytical dependencies. The first analytical dependence describes determining the area of groundwater intake from the groundwater level, considering the presence of artificial coatings, infiltration, evaporation, and transpiration, as well as the effect of evapotranspiration. The second dependence determines the area of influence of the missile and artillery danger from the type of weapon, the explosive charge, calibre (diameter), and territorial conditions, the key indicators of the content of which in the territory of the critical infrastructure object, which suffered damage, are further determined by expert calculation using natural samples of soils and groundwater. The third dependence determines the impact of harmful (polluting) substances on groundwater in the territory of the critical infrastructure object, which suffered damage, depending on the process of groundwater movement in the area of the emergency, taking into account the hydraulic pressure and water yield coefficient; the process of distribution of chemically dangerous substances in groundwater, taking into account the coefficient of hydrodynamic dispersion and the velocity of groundwater; convective diffusion of chemically hazardous substances, taking into account the kinetics of sorption. The fourth dependency allows us to choose an efficient concept for the organisation of groundwater monitoring on the territory of a critical infrastructure object that suffered damage based on the variation of formalised parameters for solving individual problems. The initial conditions of the mathematical model are related to the presence of chemically dangerous compounds in groundwater at the maximum permissible concentration level. The boundary conditions of the mathematical model relate to the non-overgrowth of consequences beyond the object level in terms of the number of victims. Keywords: mathematical model, groundwater, missile and artillery damage, critical infrastructure object, emergency prevention.

Qualitative indicator of foreign adapted potato varieties under the influence of fertilizers in the conditions of southeastern Kazakhstan

This paper presents the results of field experiments to study the effect of fertilizers on the quality of potato tubers of the Tien Shan, Gala, Alladin and Innovator varieties grown in the foothill zone of south-east Kazakhstan. The novelty of the research lies in the fact that for the first time in Kazakhstan she is studying the effect of fertilizers on the quality of potato tubers of four varieties grown in the foothill zone of the south-east of the country. The results obtained can be used to develop recommendations for the use of fertilizers for potatoes in this region. The results of the study are consistent with data from similar studies conducted in other regions of Kazakhstan and other countries. It has been established that the application of fertilizers helps to increase the content of dry matter, starch and total sugar in potato tubers. At the same time, the greatest starchiness of the tubers was noted when applying increased doses of mineral fertilizers or the combined use of mineral and organic fertilizers. The nitrate content in potato tubers of the Tien Shan, Gala and Aladdin varieties did not exceed the maximum permissible concentration (MPC - 250 mg/kg). In the tubers of the Innovator variety, the nitrate content was below the maximum permissible concentration, even in the control. Fertilizer application is an effective way to improve the quality of potato crops.

Lanthanide-based Single-Chain Nanoparticles as "Visual" Pass/Fail Sensors of Maximum Permissible Concentration of Cu2+ Ions in Drinking Water.

The maximum permissible concentration (m.p.c.) of Cu2+ ions in drinking water, as set by the World Health Organization (WHO) is m.p.c. (Cu2+)WHO = 30 μM, whereas the US Environmental Protection Agency (EPA) establishes a more restrictive value of m.p.c. (Cu2+)EPA = 20 μM. Herein, we develop-for the first time ever-a family of m.p.c. (Cu2+) "visual" pass/fail sensors based on water-soluble lanthanide-containing single-chain nanoparticles (SCNPs) exhibiting an average hydrodynamic diameter less than 10 nm. Both europium (Eu)- and terbium (Tb)-based SCNPs allow excessive Cu2+ to be readily detected in water, as indicated by the red-to-transparent and green-to-transparent changes, respectively, under ultra-violet (UV) light irradiation, occurring at 30 μM Cu2+ in both cases. Complementary, dysprosium (Dy)-based SCNPs show a yellow color-to-transparent transition under UV light irradiation at approximately 15 μM Cu2+. Eu-, Tb- and Dy-containing SCNPs prove to be selective for Cu2+ ions as they do not respond against other metal ions, such as Fe2+, Ag+, Co2+, Ba2+, Ni2+, Hg2+, Pb2+, Zn2+, Fe3+, Ca2+, Mn2+, Mg2+ or Cr3+. These new m.p.c. (Cu2+) "visual" pass/fail sensors are thoroughly characterized by a combination of techniques, including size exclusion chromatography, dynamic light scattering, inductively coupled plasma-mass spectrometry, as well as infrared, UV and fluorescence spectroscopy. This article is protected by copyright. All rights reserved.

Method of neutralization of nitrogen oxides in area of low-temperature plasma

In the production of 1 ton of oxalic acid, 2000 m3 of gases with an average content of 2–2.5% of nitrogen oxides are emitted into the atmosphere. The existing methods of air purification from nitrous gases have a number of disadvantages and therefore cannot be widely used in industry. Based on theoretical and experimental studies, a new method for the thermal decomposition of nitrogen oxides has been developed, which provides for the sanitary purification of waste gases in the production of oxalic acid, up to the maximum permissible concentrations. The process of thermal decomposition of nitrogen oxides in the temperature range from 500 to approximately 50000С has been studied. To achieve such temperatures, an arc plasma torch with a tungsten cathode and a copper anode was used. The degree of decomposition was determined by measuring the NO concentration at the inlet and outlet by the evacuated flask method. The effects of gaseous (hydrogen, ammonia, methane, natural gas), liquid (kerosene, gasoline, fuel oil), and solid reducing agents (coke, coal, graphite) on the decomposition reaction of nitrogen oxides were also studied.

Purification of surface water by using the corona discharge method

Purpose. The primary objective of this research is to develop a technology for achieving water quality at the level of Maximum Permissible Concentrations (MPC) required by sanitary regulations and norms. Methods. To meet these regulatory requirements, experimental studies were conducted to analyze the chemical and microbiological composition of water, focusing on parameters such as the total microbial count (quantity/ml), coliform bacteria (quantity/ml), coliphages (quantity/100 ml), clostridia (cl/20 ml), and other harmful substances. The research also examined water disinfection processes depending on the autumn and winter seasons of the year. Findings. To assess the device’s effectiveness, the research determined the optimal ozone concentration and contact time in the disinfection chamber. The findings indicate that 0.6 grams per hour (G = 0.6 g/hour) of ozone (O3) per cubic meter of surface water is sufficient for the removal of harmful microbiological substances. Originality. The primary innovation in this research lies in the establishment of parameters for an ozone generator utilizing a novel corona discharge method. The study introduces both theoretical frameworks and practical methodologies for effectively disinfecting surface waters using this innovative technique. Practical implications. This case study offers insights that can be applied and replicated in regions facing similar water quality challenges.

Detailed chemical analysis of soils and identification of priority pollutants on the territory of the state aviation airfield (Krymsk)

In connection with the intensification of military activities, environmental problems have worsened in large-scale territories. The primary task is to create lists of priority pollutants of environmental objects that are mandatory for control at landfills for various purposes, military bases, airfields. The paper presents the data of a detailed geochemical analysis of the soils of the state aviation airfield territory, on the basis of which priority contaminants were identified taking into account their gross content, hazard classes and the frequency of exceeding dangerous concentrations relative to the background. In the Krasnodar Territory (Krymsk), 32 samples from the territory of the state aviation airfield were analyzed over 4 years of research, and background concentrations of 22 metals, petroleum products, formaldehyde and nitrate nitrogen were also established. To determine the hazard classes of metals with unspecified maximum permissible concentrations, a correlation analysis was carried out comparing the hazard classes of substances and their clarks. Based on the results of the study, a list of pollutants recommended for control has been compiled including cesium, arsenic, scandium, niobium, lead (hazard class I); antimony, formaldehyde, nitrate nitrogen (II); petroleum products (III). The variability of the distribution of concentrations of pollutants on the airfield territory depends on the specifics of the operation of aircraft and special equipment for flight support. But at all sampling points (beginning – end, runway perimeter; taxiways; under the glide path), the main soil pollutant is arsenic, which concentrations exceed background concentrations by 16–36 times. The dangerously high content of petroleum products, formaldehyde, nitrate nitrogen, and scandium and caesium in some points in the airfield soils has been also found.

A Comprehensive Assessment of the Ecological State of the Transboundary Irtysh River (Kazakhstan, Central Asia)

The diverse anthropogenic load on the transboundary Irtysh River necessitates an assessment of its ecological state, which was the goal of this work. We conducted this research in July 2023 in the upper and lower reaches of the Kazakh part of the Irtysh basin. We determined transparency; temperature; pH; salinity (TDS); oxygen, N-NO3, N-NO2, N-NH4, PO4, Mn, Fe, Si, Cd, Cu, Zn, Pb, Cr, Co, and Hg contents; permanganate index; and zooplankton variables at 27 stations. We assessed the ecological state of the river by comparing the contents of pollutants with their maximum permissible concentrations (MPCfw), Classification Scales, and bioindications. An excess of MPCfw was detected for N-NO2, Cu, and Fe and locally for Cr and Zn. According to the Classification Scales, most analysed variables corresponded to slightly polluted waters; N-NO2, Cr, and Zn corresponded to moderately and heavily polluted waters. Zooplankton was represented by 82 species, with an average abundance of 6728 individuals/m3, biomass of 2.81 mg/m3, Shannon index of 1.99–2.08 bit, ∆-Shannon of 0.09, and average individual mass of 0.0019 mg. The spatial distribution of abiotic and biotic variables indicated increased organic and toxic pollution downstream in the Irtysh. Potential sources of pollution of the Irtysh basin are discussed.

Technological methods for increasing the yield and fertility reproduction when growing zucchini on sod-podzolic light loamy soil in natural and climatic conditions of Republic of Belarus

Relevance. To improve the quality of life and expand the taste preferences of the population of Belarus, it is necessary to expand the range of vegetable crops with high yields, marketability and product quality, adapted to the natural and climatic conditions of the republic. In this regard, improving technological methods for cultivating such a crop as zucchini (Cucurbita pepo L.) is of scientific and practical importance. Materials and Methods. The research was carried out on the territory of a private farm in the village of Chukhny, Smorgon district. Field and laboratory studies were carried out using generally accepted methods and guidelines. Results. Substantiated the feasibility of cultivating green manure crops in combination with the local application of thermoammonia-disinfected compost when growing zucchini in seedlings on sod-podzolic light loamy soils in the natural climatic conditions of Belarus. The developed technological methods ensure the reproduction of soil fertility, increased yield, and production of high quality products without the use of mineral fertilizers. When using green manure and disinfected compost, the nitrate content in zucchini cv. Bonus, grown without mineral fertilizers, was in the range of 280-320 mg/kg. To reproduce the fertility of soddy-podzolic light loamy soils when growing zucchini in the natural climatic conditions of Belarus, it is advisable to use oats, oilseed radish and peas as green manure fertilizers. This technological technique increases the content of organic matter in the soil by 0.8-1.3 %. Together with green manure, adding thermo-ammonia-disinfected compost into a hole when planting zucchini seedlings ensures an increase in organic matter content by 1.2-1.5 % in the compost localization zone. During the decomposition of organic matter of green manure crops and disinfected compost applied locally, nutrients are released in quantities sufficient to form a high yield of zucchini with a nitrate content below the maximum permissible concentration. Thus, when grown on soddy-podzolic light loamy soils in the natural climatic conditions of Belarus, the proposed technological methods make it possible to obtain high-quality products and significantly increase the yield of zucchini due to green manure in combination with the local application of disinfected compost without the use of mineral fertilizers.