The continuing anthropogenic pollution of the Ile River occurs both by transboundary runoff and as a result of discharges of industrial, agricultural, and domestic wastewater on the territory of Kazakhstan. With this amount of pollution, the river’s capacity for self-purification is very limited, and in some cases practically exhausted. Hydrochemical and toxic indicators in the Ile River basin were analyzed based on water sampling from the Chinese–Kazakh border station to 37 km downstream of the hydroelectric power plants (HPPs). Heavy metals were determined by flame AAS methods. The self-purification capacity (SPC) was determined for cadmium by 28–81%, copper 15–66%, zinc 22–37%, and cobalt 5–9% while the nickel self-purification of water did not occur. The SPC was influenced by the Kapshagai reservoir. The identified main regularities of the anthropogenic transformation of water quality and self-purification capacity of the river will help both in solving the problems of river pollution and in the development of necessary measures aimed at the protection of water resources from pollution and depletion.

The article presents the results of the study conducted on the territory of the Almaty agglomeration (AA) in the first half of 2019. During the expeditionary studies, sampling was carried out at 30 permanent points established taking into account the degree of anthropogenic load and sources of technogenic pollution. The content of trace elements (TE) in the snow was determined by a flame atomic absorption spectrometric method using an AA-7000 spectrophotometer with a hollow cathode lamp and with a nozzle burner operating on an acetylene-air mixture. The paper considers the amount of content of copper and lead in the snow, as well as the nature of their distribution over the study area. Calculations were carried out on the number of depositions of the TE in question per unit area over the territory of the agglomeration, with the allocation of zones experiencing the highest technogenic load.

The paper presents primary material on determining the presence of micro- and macroplastics in Markakol Lake, one of the high-mountainous and unique water bodies of Kazakhstan, conditionally undisturbed, but vulnerable to anthropogenic pollution. In the course of work, micro- and macroplastics were detected in all selected samples in the water area of the lake and its main tributaries, the Urunkhaika, Topolevka, Tikhushka, Matabai, Elovka rivers. When determining micro- and macroplastics, we were guided by the method of analysis in aquatic environment, NOAA research program, developed by American scientists Masura J. et al, which is used in many countries. Concentrations and sizes of MP found in the water of the main tributaries of the rivers Urunhaika in concentrations up to 211.4 µg/m3, Tikhushka – 97.9 µg/m3, Zhirelka – 67.8 µg/m3, Topolevka – 157.2 µg/m3, Matabai – 78.3 µg/m3. Concentrations of MP in the surface water layer of the lake detected during 15 minute trawling at distances from 438 m to 841 m occur in sieve mesh sizes of 1.0 mm – 316.7 µg/m3 and 0.315 mm – 520.8 µg/m3. The total concentration of detected micro- and macroplastics coming with tributaries was – 150 µg/m3, in the lake water area – 837.4 µg/m3. The sizes of plastic debris found both in river waters and along the lake water area ranged from mesoplastic debris (fishing line net fragments, foam balls, plastic bags, plastic bottles, wrappers, food labels and packaging, etc.) to microplastic particles detected using a microscope with 40X magnification in size ranges of 25 mm, 1.0 mm and 0.315 mm. Sources of MP depend on local human activities (fishing, transportation, waste disposal etc.).

The Ile River is the main water artery of the Lake Balkhash basin and the main fresh water resource supplying the south-eastern part of Kazakhstan. Increasing human economic activity makes it necessary to assess the anthropogenic load of the river on various ecosystems, including possible harmful effects. The assessment of anthropogenic load on the Ile River ecosystem was realized by the anthropogenic load fraction indicator and by the values of the chemical substance inflow modulus. For this purpose, the Ile River was divided into 3 sections: section I—from the border post HP Dobyn to 164 km above Kapshagai hydroelectric power plant (HPP); section II—between the points 164 km above and 37 km below Kapshagai HPP; and section III —from 37 km below HPP to Ushzharma village. The anthropogenic load strongly depends on the share of anthropogenic impact contributed by pollutants. Characteristic pollution components are copper, and in some cases zinc, ammonium, and nitrite nitrogen. The assessment of anthropogenic load also considers organic and biogenic substances in the chemical composition of river water. The variability in the volume of dissolved chemical inflows in different sections of the river made it possible to assess the transformation of anthropogenic load along the length of the Ile River.

The article presents the results of a study on the contamination of the soil cover of the Zhetysu Region of the Republic of Kazakhstan by polychlorinated biphenyls (PCBs). Soil samples were collected in 2024...2025 at 52 monitoring sites located in different natural and landscape zones of the region. The PCB content was analyzed using gas chromatography with an electron capture detector in accordance with the requirements of regulatory documents. The presence of polychlorinated biphenyls was detected in all studied soil samples. The total PCB concentrations ranged from 0.010 to 1.631 µg/kg. A significant diversity of individual congeners was identified, including indicator (“marker”) and dioxin-like compounds. The highest concentrations of the pollutant were recorded in soils of urbanized areas. A comparative analysis of the research results for 2024 and 2025 showed a noticeable decrease in PCB concentrations in 2025. This may be associated with seasonal features of sampling, redistribution of pollutants within the soil profile, and spatial heterogeneity of their distribution. The obtained results indicate a relatively low level of soil contamination in the region by polychlorinated biphenyls and can be used in organizing environmental monitoring of persistent organic pollutants within the framework of the Republic of Kazakhstan’s implementation of its international obligations under the Stockholm Convention.

This study presents long-term background concentration estimates for hydrochemical parameters in the Shu River at the Kaynar transboundary section for 2002–2025 and assesses chemical mass transport across this section. Annual mean values for 31 hydrochemical parameters were analyzed; 533 annual values were processed, and 498 remained after statistical extremes were excluded from background-concentration calculations. Background concentrations were estimated as one-sided confidence limits of the mean at a 0.95 confidence level. The Shu River water is characterized by a bicarbonate-sulfate composition and moderately elevated mineralization. Background-level exceedances of the reference maximum permissible concentration (MPC) values were observed for sulfate, nitrite nitrogen (NO₂-N), and copper. Suspended solids were assessed separately because the applicable criterion is expressed relative to the background concentration rather than as a fixed MPC value. The comprehensive water pollution index (CWPI) indicated moderate pollution in most years, with high pollution levels in 2002, 2003, 2006–2008, and 2016. Annual mass transport of ionic constituents increased from 555.2 thousand metric tons in 2021 to 899.6 thousand metric tons in 2023, while nutrient mass transport ranged from 3.14 to 3.55 thousand metric tons per year. Nitrate nitrogen (NO₃-N) made the largest contribution to nutrient mass transport. The results support regional water-quality assessment and water-protection planning in arid transboundary river basins.