Kazakhstan is known as a country with a complex radioecological situation resulting from different sources such as a natural radiation background, extensive activities of the industrial system of the former Soviet Union and a well-known testing of nuclear power weapons occurred in the Semipalatinsk Test Site (STS) area. The present study focuses on the assessment of the background of dicentric chromosomes in Kazakhstan’s population, which is the starting point in the dose assessment of irradiated people, since the baseline level of spontaneous dicentrics can vary significantly in different populations. In this context, aiming to determine the background frequency of chromosome aberrations in the population of Kazakhstan, considering the heterogeneity of natural radiation background levels of its large territory, a selection of 40 control subjects living in four cities of North, South, West and East Kazakhstan was performed. The cytogenetic study on the selected groups showed fairly low background frequency values of chromosome aberrations (0.84 ± 0.83 per 1000 cells), comparable with other data in the literature on general populations, reporting background frequency values between 0.54 and 2.99 per 1000 cells. The obtained results should be taken into account when constructing the dose–effect calibration curve used in cytogenetic biodosimetry, as a “zero” dose point, which will reduce the uncertainty in quantifying the individual absorbed dose in emergency radiological situations.

Atmospheric deposition in industrial basins of Central Asia is strongly influenced by local emissions and wintertime dispersion conditions. This study characterized snowpack at 63 sampling stations across Ust-Kamenogorsk, Kazakhstan, including operational background station 1, on 24–26 February 2025 after a 116-day accumulation period. Major ions were determined in a spatially distributed exploratory subset of 16 samples, and trace elements were measured in samples from all 63 stations by means of inductively coupled plasma mass spectrometry and optical emission spectrometry. Mean meltwater pH and total dissolved solids were 6.55 ± 0.34 and 37.3 ± 18.0 mg L⁻¹, respectively. Charge-balance errors for the 16 hydrochemical samples ranged from −0.3% to +0.7%. Using the contamination index based on exceedances of the current Kazakhstan water-quality thresholds, 48 stations had CI < 1, seven had CI = 1–3, and eight had CI > 3; the highest value (60.21) occurred at station 26. Principal component analysis showed that the first three components explained 53.6% of the variance and separated a broad mineral/industrial aerosol association from a Pb–Cd–Zn association consistent with non-ferrous metallurgy and mixed urban sources. Cadmium was therefore interpreted as the principal contributor to the MPC-normalized index at the most affected stations, rather than as the dominant component by absolute concentration. The dissolved fraction can be mobilized during spring melt, indicating a potential pathway to soils and receiving waters, although direct ecological or human-health risk was not quantified. Station-level point mapping and projection along the NW–SE axis showed localized multi-element maxima rather than a monotonic citywide gradient.

Snowpacks serve as an informative deposition medium for assessing the spatial distribution of atmospheric fallout and technogenic load in areas with persistent snow cover. This study examined the chemical element content in the solid fraction of the snow cover (SFSC) in Pavlodar Region. Fifty-five samples were collected, covering industrial, buffer, non-industrial, and background zones. The elemental composition of the SFSC was determined using inductively coupled plasma mass spectrometry (ICP-MS). The results revealed marked spatial heterogeneity in the distribution of chemical elements. The Pb levels detected exceeded background values by a factor of 2 to 100, indicating a significant aerotechnogenic impact on the study area. Elevated concentrations (of Pb, Sr, and V) and peak accumulation levels were recorded in the zones directly affected by industrial facilities and in the corresponding buffer zones subject to this influence. Principal component analysis (PCA) identified two main factors of elemental composition variability. The first principal component (PC1) was characterized by high positive loadings primarily associated with rare-earth elements (REEs). The observed spatial pattern reflects a combination of local industrial impact and the regional transport of chemical elements. This study represents a pilot phase of long-term monitoring aimed at assessing the spatial distribution of chemical elements in snow cover and identifying areas of elevated technogenic impact.

The 2021 revision of the Environmental Code of the Republic of Kazakhstan was introduced to align with the World Health Organization (WHO) air quality guidelines and the national carbon neutrality strategy for 2060. The revised Code reflects a transformation of environmental governance, including the transition towards a low-carbon and climate-oriented policy framework, the tightening of air quality standards, the strengthening of environmental monitoring, the expansion of region-specific regulatory mechanisms, and increased emphasis on the implementation of Best Available Techniques (BAT). This study presents a comparative analysis of atmospheric pollutant emissions across regions and industrial sectors, including major pollutants such as PM_2.5, SO₂, CO, NO₂, and others. The analysis considers ambient air quality indicators, pollutant composition, the chemical composition of atmospheric precipitation, regional industrial profiles, and changes observed during the reform period. The findings demonstrate substantial regional and pollutant-specific heterogeneity in air-quality dynamics. Although stationary-source emissions decreased by approximately 5–6% between 2021 and 2024, no statistically significant improvement in the assessed ambient-air indicators was identified between 2021 and 2025. Persistent high pollution levels and episodic particulate matter exceedances remained evident in several cities. These findings provide an empirical basis for further assessment of the environmental outcomes of the revised Environmental Code.

It is known from the world literature that for EPR spectrometry for emergency dosimetry, where doses from 0.5 Gy and higher are used, the quality and reliability of calculating the experimental dose depends on the parameters of recording spectra (accumulation time, microwave power).This article describes the results of the development and application of a method for optimizing the parameter of recording EPR spectra on human tooth enamel, such as microwave power, but in the range of emergency radiation doses (from 1 Gy to 5 Gy), under conditions of a local radiation incident based on a biodosimetric laboratory. The results showed that the obtained experimental microwave power value of 5 MW is the most effective parameter for improving the quality of EPR spectra of human tooth enamel for a range of emergency radiation doses, even taking into account different types of spectrometers on which measurements are carried out. Optimization of the parameter for recording EPR spectra, in particular microwave power, improves the quality of the obtained spectra for the range of emergency radiation doses, even taking into account different types of spectrometers on which measurements are carried out.

Atmospheric pollution by fine particulate matter (PM_2.5) poses a severe threat to public health in industrial regions of Kazakhstan, such as Ust-Kamenogorsk and Pavlodar, where a sharp continental climate exacerbates toxic element accumulation. This study aimed to compare the elemental composition of PM_2.5 in Ust-Kamenogorsk and Pavlodar using ICP-OES (FPI EXPEC-6500) and ICP-MS (FPI SUPEC-7000), identify key pollution sources through chemometric approaches, and quantitatively evaluate inhalation health risks for adult and pediatric populations. Principal component analysis (PCA) revealed contrasting emission profiles: Ust-Kamenogorsk was dominated by non-ferrous metallurgical signatures, whereas Pavlodar was driven by high-ash coal fly ash from thermal power plants, ferrous metallurgy, and petrochemical operations. Non-carcinogenic health risks were exceptionally high in both cities, with cumulative hazard indices exceeding the safe benchmark (HI = 1.0) by over 500-fold, predominantly driven by extreme contributions of Zn (HQ_inh = 304.7) and Al (HQ_inh = 129.5). Carcinogenic risks for adults were governed by Cr and As, reaching 8.7·10⁻⁴ and 4.1·10⁻⁴ in Ust-Kamenogorsk, and 4.4·10⁻⁴ and 5.0·10⁻⁴ in Pavlodar, respectively—exceeding the maximum acceptable threshold (1·10⁻⁴) by up to 9-fold. For children, Cr presented an elevated risk (1.7·10⁻⁴) in Ust-Kamenogorsk, while borderline values were observed in Pavlodar.