Introduction. The main purpose of preventive medicine is to protect public health from the harmful effects of the human environment. In industrial areas of large industrial countries, the problem of sanitary protection of soils is put forward as one of the most acute. Fluorine is one of those trace elements that receives a lot of attention due to its harmful effects on the environment, human and animal health. The main sources of industrial soil contamination with fluorinated compounds are enterprises producing aluminum and steel, ceramics, phosphorous fertilizers, glass, cement and brick factories.

The purpose of the study. To conduct a hygienic assessment of the fluoride content in the soil of territories serviced by the FMBA of Russia and identify possible potential sources of its entry into the soil using the example of Obninsk, the Kaluga Region, and Peresvet, the Moscow Region.

Materials and methods. Literature sources on the effects of fluorine on the environment and public health were studied, and the following databases were used in the search: PubMed, Scopus, Web of Science, MedLine, Global Health, RSCI. Field studies of fluorine content in soil for various purposes were conducted in Obninsk, the Kaluga region and in Peresvet, the Moscow region.

Results. Based on the results of field studies, it was found that there were five soil samples in Obninsk, the Kaluga region and Peresvet, the Moscow region (three points in Peresvet, the Moscow region, two points in Obninsk, the Kaluga region), did not meet the hygienic standard for the content of fluorine (water-soluble form) and exceeded the maximum permissible concentration by 1.2–1.5 times. The conducted analytical search for data on the types of enterprises, which included production features, chemical composition of emissions, location (proximity of enterprises to the points where the maximum permissible concentration of fluorine in the soil was detected) allowed creating a list of potential sources of soil contamination with fluorine.

Limitation. Due to the fact that the studies were conducted on soils selected in territories with a similar soil type, excess fluorine was detected once during the study, which requires further observations.

Conclusion. A screening study of the soils of the territories serviced by the FMBA of Russia on the principle of “samples of unknown composition” revealed the points where the excess of the maximum permissible concentration of fluorine (water-soluble form) in the soil exceeds the established standards. Monitoring the levels of fluoride in the soil, only in the area of exposure to large industries, such as aluminum production holdings, is insufficient. As we can see, in cities where even small enterprises are located, which can be sources of fluoride entering the environment, it is necessary to monitor not only atmospheric emissions, but also the fluorine content in the soil, at least once a year.

Compliance with ethical standards. The study does not require submission to a biomedical ethics committee or other documents.

Contribution: Evseeva I.S. – concept and design of research, collection of material and data processing, text writing, editing; Ushakova O.V. – concept and design of the study, writing, editing;  Zhernov Yu.V. – research concept, editing. All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interest. The authors declare no conflict of interest.

Funding. The study was carried out within the framework of a state assignment.

Received: October 14, 2025 / Accepted: November 3, 2025 / Published: December 19, 2025

Introduction. A temporary decline in incidence and mortality caused by influenza and  acute respiratory viral infection (ARVI) during the COVID-19 pandemic did not decrease their significance for population health. Despite a well-known regulation role that belongs to social and environmental conditions in phase transformations of an epidemic process, there are scarce studies in research literature that focus on investigating complex effects produced by environmental factors on the clinical course of the analyzed infections.

The aim of this study. To identify social-and hygienic determinants of influenza and ARVI incidence.

Materials and methods. The study results were obtained by using open data published by Rosstat and departmental materials of Rospotrebnadzor over the period between 2010 and 2022. Overall, 232 indicators were used in the study; they described hygienic and epidemiological aspects, peculiar climatic conditions, financial and social parameters as well as people’s habits and healthcare infrastructure in Russian regions taken on the annual basis.

Results. The study found several key factors affecting influenza and ARVI incidence. They included the following indicators: volumes of pollutant emissions into ambient air (r=0.12 and r=0.23 respectively); proportion of workers exposed to working conditions not conforming to safe standards (r=0.13–0.29); UVB, average monthly horizontal radiation and average precipitation volumes (r=0.12–0.7); the proportion of urban population (r=0.13 and r=0.59); volumes of alcohol sales (r=0.27–0.53); gross regional product (r=0.08–0.42); the number of middle-level healthcare workers (r=0.14; r=0.36); capacity of polyclinics (r=0.41) and others.

Limitations. The study limitations are related to the analyzed dataset (selected indicators and time period).

Conclusion. The identified peculiar effects produced by these factors as well as lifestyles can be used for substantiating medical and preventive activities aimed at improving the sanitary-epidemiological situations in the country.

Compliance with ethical standards. The study did not require the conclusion of a biomedical ethics committee or other documents (the study was performed using publicly available official statistics).

Contributions:
Zaitseva N.V. — research concept and design, editing the text;
Kleyn S.V., Kiryanov D.A. — writing and editing the text;
Glukhikh M.V. — data collection and statistical analysis, writing the test.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interest. The authors declare no conflict of interest.

Funding. The study had no sponsorship.

Received: August 1, 2025 / Accepted: November  3, 2025 / Published: December 19, 2025

Introduction. Untreated wastewater poses a significant threat to public health and the environment. Not all treatment facilities are equally effective.

Purpose of the study. Comparison of the pathogenic potential of bacterial isolates of the Enterobacteriaceae family isolated from wastewater and surface water after treatment facilities (TF) in Moscow.

Materials and methods. Water samples were collected at the TF (inlet, post-treatment, and discharge) and from surface waters (upstream and downstream of the TF discharge point). Studies were conducted at Moscow’s TF: Zelenograd Wastewater Treatment Plant (ZWTP), Yuzhnoye Butovo Wastewater Treatment Plant (YUBOTWTP), Lyubertsy Wastewater Treatment Plant (LOS), and Kuryanovsk Wastewater Treatment Plant (KOS). PCR was used to detect potentially pathogenic determinants.

Results. Isolates recovered from the analyzed water samples at the TF were established to have a higher pathogenic potential than isolates isolated from feces (F). Antibiotic resistance genes were found in 7.5% of E. coli isolates isolated only from the TF. Pathogenic determinants were significantly more common in isolates from the TF (mrkD and CFU for Klebsiella, aggR and ipaH for E. coli). All stations reduced the number of isolates after the treatment cycle (2–11 times for E. coli and 2–4 times for Klebsiella), except for YUBOS, where the number of Klebsiella isolates decreased by only 15%, while E. coli even increased by 14%.

Limitations. We studied isolates of the Enterobacteriaceae family from Moscow TF and human feces (F) from the genus Klebsiella (157 wastewater and 117 F isolates) and Escherichia coli (100 wastewater and 80 F isolates), which represents a sufficient reference sample.

Conclusion. Overall, bacterial isolates of the Enterobacteriaceae family have been isolated from wastewater (including untreated wastewater) from Moscow’s wastewater treatment plants (WWTPs) and have a higher pathogenic potential than isolates recovered from human feces. Furthermore, water treatment at Moscow’s wastewater treatment plants (except for the YUBOTWTP) has been shown to reduce the level of bacterial contamination of wastewater by Enterobacteriaceae by four orders of magnitude. However, no reduction in pathogenic potential has been observed in viable isolates recovered from the discharge channel or from surface waters downstream of the WWTPs discharge.

Compliance with ethical standards. The study of biological material from humans was approved by the Local Independent Ethics Committee (Minutes No. 98A of the meeting of the Local Independent Ethics Committee of the National Medical Research Center of Coloproctology named after A.N. Ryzhikh, dated 07/16/2018).

Contribution.
Pay G.V. – research concept and design, experimental work, statistical processing, text writing, editing;
Kurbatova I.V. – collection and processing of samples, bacterial cultivation;
Novozhilov K.A. – collection and processing of samples, bacterial cultivation;
Mania T.R. – collection of material, editing;
Yudin S.M. – editing, approval of the final version of the article;
Zagainova A.V. – concept and design of the study, editing, approval of the final version of the article.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interest. The authors declare no conflict of interest.

Funding. The study was conducted as part of the research project “Development of standardized methods, including sampling, for determining microbiological and parasitological contamination of wastewater.” State contract No. 2123388100152000000000000/145.001.216 (code “Wastewater”), November 12, 2021.

Received: February 18, 2025 / Revised: April 25, 2025 / Accepted: June 26, 2025 / Published: December 19, 2025

Accidents at chemically hazardous facilities pose a significant threat to public health and the environment. With the growing scale of chemical production and the widespread use of hazardous chemicals, there is a growing need for a systematic risk assessment at all stages of the chemical product life cycle.

The objective of this study was to identify and analyze the risk factors contributing to accidents at chemically hazardous facilities.

To prepare this review, a literature search was conducted for scientific and regulatory publications on the assessment of chemical risks at facilities handling hazardous substances. The search was carried out using scientific databases such as Google Scholar, eLibrary, and CyberLeninka. Special attention was given to reports from the last ten years (2015-2025), although earlier sources were also included if they contained significant information relevant to the topic.

The main causes of accidents at different stages of chemical production were identified, and incident types were classified according to the physical state of the hazardous chemicals and the conditions of their release. The roles of technical malfunctions, human error, and natural factors were highlighted. Accidents at chemically hazardous facilities (CHFs) were shown to result often from a combination of several interrelated factors that can amplify one another.

Preventing such accidents requires strict compliance with industrial safety regulations, continuous monitoring of working conditions, and regular inspection of equipment. Ensuring chemical safety demands a comprehensive approach, including technological modernization, personnel training, regulatory improvements, and interagency cooperation. Combining these elements will reduce the likelihood of accidents and improve preparedness for effective response when they occur.

Contribution:
Lebed-Sharlevich Ya.I. – collection and processing of material, writing a text;
Mamonov R.A. – editing;
Savostikova O.N. – editing.
All authors are responsible for the concept and design of the study, integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interest. The authors declare no conflict of interest.

Funding. The study was conducted within the framework of the State Assignment.

Received: August 1, 2025 / Accepted: November 3, 2025 / Published: December 19, 2025

Introduction. Existing scientific papers on burnout syndrome in medical staff (MS) do not address the relationship between the objective health, health related quality of life (HRQoL), and subjective social well-being (SSWB).

Material and methods. The study involved forty seven doctors and nurses of polyclinic institutions of an industrial city with varying degrees of burnout severity. Their SSWB was studied using the PWI-A R. Cummins questionnaire, HRQoL – using the EQ-5D-3L questionnaire. In the statistical analysis, the χ² and Mann–Whitney criteria, Spearman rank correlation coefficient were used.

Results. The identified patterns of burnout severity were independent of age and length of service. Inverse relationships were found between the degree of burnout development and indicators of SSWB (standard of living, confidence in the future) and presence of anxiety/depression as parameter of HRQoL.

Limitations. The small sample size is a limitation. It is necessary to increase the sample size and expand the survey instruments used also to predict the physical, mental health, SSWB.

Conclusion. The study revealed links between burnout and morbidity, SSWB, HRQoL. Given these links, it is important to implement comprehensive programs aimed at improving mental and physical well-being.

Compliance with ethical standards. The study was performed in accordance with ethical standards and approved by the Local Ethics Committee of the East-Siberian Institute of Medical and Ecological Research (conclusion No. 5 dated March 21, 2023). All participants gave informed voluntary written consent to participate in the study.

Contribution:
Dyakovich M.P.  – concept and design of the study, mathematical and statistical processing, text writing, editing, responsibility for the integrity of all parts of the article.

Conflict of interest. The author declares no conflict of interest.

Funding. The work was performed within the funds allocated for the implementation of the State task for the East-Siberian Institute of Medical and Ecological Research.

Received: October 29, 2025 / Accepted: November 3, 2025 / Published: December 19, 2025

Introduction. Dermatoses occupy a significant place in the structure of occupational morbidity of workers in industrial enterprises exposed to xenobiotics. Despite preventive measures and the use of personal protective equipment, the prevalence of pathology among this category of workers remains high. A promising direction for the development of personalized approaches to the prevention of occupational dermatoses is the study of the contribution of genotype to the development of such diseases.

Materials and methods. The study included six hundred sixty employees of the enterprise working in harmful conditions, whose dermatological status was assessed. The group profile of occupational risk was determined using a point assessment. Analysis of the polymorphic state of detoxification and antioxidant protection markers rs9282861 of the SULT1A1 gene (G2663A); rs4880 of the SOD2 gene (C47T); rs1001179 of the CAT gene (G262A); rs12248560 of the CYP2C19*17 gene (C806T); rs1799930, rs1799931, rs1208, rs1799929 of the NAT2 gene was carried out in 122 employees of the enterprise. The relationship between genotypes and combinations of identified alleles with established skin diseases was assessed using the odds ratio (OR, 95% CI) with a log-additive inheritance model. Logistic regression analysis was performed taking into account the sex of the donors. SPSS Statistics v.22 software was used for statistical data processing.

Results. The main unfavorable production factors are chemical factors combined with a heating microclimate. Among female workers of the studied production, the risk of skin diseases was 1.28 times higher than among men. A combination of alleles of the SULT1A1, SOD2, CAT, CYP2 genes was revealed, which increases the risk of developing dermatological pathologies in employees of the enterprise working in harmful working conditions (OR = 9.69; 95% CI: 7.46–11.91). Sexual dimorphism in resistance to harmful production factors associated with polymorphisms rs1799929; rs1799930; rs1799931 of the NAT2 gene was found: men with a fast acetylating phenotype demonstrate higher resistance compared to women.

Limitation. The obtained results need to be confirmed in larger studies.

Conclusion. The obtained data can be used in the development of personalized approaches to the prevention of occupational dermatological pathology, including early identification of risk groups and targeted use of preventive measures.

Compliance with ethical standards. The study was conducted in accordance with the ethical standard of the World Medical Association Declaration of Helsinki “Ethical Principles for Medical Research Involving Human Subjects” as amended in 2000. The study was approved by the local ethics committee (protocol No. 1 of April 07, 2021). All participants gave informed voluntary written consent to participate in the study.

Contribution:
Gorenskaya O.V. – data and statistical processing, text writing;
Kotnova A.P. – laboratory research;
Ilyushina N.A. – concept of the study, data processing, text writing;
Egorova O.V. – laboratory research, data processing;
Krasavina E.К. – concept of the study, collection and processing of material;
Kryuchkova E.N. – editing, text formatting;
Yatcyna I.V. – concept of the study.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interest. The authors declare no conflict of interest.

Funding. The study had no sponsorship.

Received: August 14, 2025 / Accepted: October 15, 2025 / Published: December 19, 2025

Introduction. The literature contains works devoted to physiological studies of railway dispatchers and locomotive crew drivers. There is information from individual authors about the impact of psychoemotional stress on the health of employees. Studies of the functional condition of railway car maintenance inspectors have not been conducted, and their work is difficult and stressful, therefore, the implementation of these studies is an urgent task.

The purpose of the work. To study the functional state in car inspectors and repairers to determine the quantitative characteristics of the labor process factors.

Materials and methods. Studies were conducted on the cardiovascular system, visual and auditory analyzers, neuromuscular apparatus, and the assessment of physical labor intensity.

Results. The results of a study of the cardiovascular system (CVS) in car inspectors and repairers showed that during work, the heart rate in the subjects ranged from 120 to 140 beats per minute, reaching an average of 128.5±1.66 beats per minute during the day shift and 136.7±2.0 beats per minute during the night shift. The results of a study of the CVS during a functional exercise test showed that the Harvard Step Test Index (HST Index) corresponded to the average level in inspection and repair of railway wagons – 61.71±1.8 (p<0.05). This is below a satisfactory level. Only 20% of the subjects had this indicator consistent with the assessment of “satisfactory”.

Limitations. Scientific research was conducted at the technical inspection stations (PTO) of major stations (Orekhovo-Zuyevo, Lyublino, Perovo, Bekasovo) of the Moscow Railway and at the stations of Chelyabinsk, Orenburg, Orsk of the South Ural Railway.

Conclusion. The results of the conducted physiological studies allowed establishing the quantitative characteristics of the factors of the labor process that affect the functional state of the inspectors and repairers of railway cars.

Compliance with ethical standards. All participants gave informed voluntary written consent to participate in the study.

Contribution:
Ovechkina Zh.V. – research concept, data collection and processing, and editing;
Kotlyar L.M. – data collection and processing, statistical data processing, and writing the text.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interest. The authors declare no conflict of interest.

Funding. The study had no sponsorship.

Received: June 3, 2025 / Revised: August 4, 2025 / Accepted: November 3, 2025 / Published: December 19, 2025

The most significant occupational hazards to which mining workers are exposed include the development of vibration-induced diseases, sensorineural hearing loss, radiculopathy, and occupational respiratory diseases. Disturbances in peripheral microcirculation, predominantly of a spastic nature, are frequently observed as a result of the peculiarities inherent in the labour process. These disturbances manifest as peripheral angiodystonic syndrome. The observed pathologies of microcirculation in this cohort of workers are associated with neurohumoral dysfunction, endothelial dysfunction, and alterations in the rheological properties of blood. The pertinence of examining microcirculatory tissue systems in miners is substantiated by the implication of microcirculatory alterations in diverse pathological processes at the premorbid stage. The complex of production factors has a damaging effect on the epidermis and dermis, which clinically can be manifested in the form of cyanosis and marbling of extremities, hyperhidrosis of palms and feet, pastosity of fingers and back of hands, xerosis, and keratosis of skin, and mycoses.

The purpose of the work is to undertake a comprehensive review and analysis of the extant literature pertaining to the mechanisms of development and methods of diagnosis of skin lesions in mining workers.

The present review article was created using the following bibliographic databases: Scopus, Web of Science, Medline, The Cochrane Library, EMBASE and RINC. The article presents the pathogenetic aspects of skin lesions in mining workers, along with recent studies by Russian and foreign authors in the field of endothelial damage markers and peculiarities of neurohumoral regulation disorders. In addition, the mechanisms of epidermis lesions in mining workers are discussed. This paper presents an overview of the extant literature on diagnostic methods for the early detection of lesions in the hypodermis, dermis, and epidermis. The methods covered include classical techniques, as well as more modern approaches. These encompass skin thermometry with cold load (cold test), capillaroscopy, thermography, plethysmography, ultrasound scanning, laser Doppler flowmetry, dermatoscopy, and methods of assessing physiological parameters of the skin. The results of the analysis of the literature are presented in this study.

The implementation of advanced diagnostic technologies and preventive measures is of paramount importance for enhancing the health status in miners and preventing occupational and comorbid diseases.

Contribution:
Yatsyna I.V. ‒ research concept and design, editing;
Astakhova I.V. ‒ collection and processing of material, writing the text.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interest. The authors declare no conflict of interest.

Funding. The study had no sponsorship.

Received: May 23, 2025 / Accepted: November 3, 2025 / Published: December 19, 2025

Introduction. An increasing chemical pollution of the environment with heavy metals (HMs) makes a significant contribution to the spread of disorders of the autonomic nervous system (ANS). In modern diagnostics and prevention of health disorders associated with the quality of the environment, a promising direction is the identification of polymorphisms of candidate genes associated with the risk of developing ANS diseases.

The aim of the study. To evaluate the characteristics of neurotransmitter regulation in adolescent schoolchildren with ANS disorders under conditions of polymorphic variants of the ApoE, SIRT1 genes and blood contamination with cadmium, lead, and arsenic. 

Materials and methods. Six hundred thirty three schoolchildren living in conditions of low-level aerogenic HM exposure (up to 1 average annual MAC) were examined, 330 of them with ANS disorders (G90.8–G90.9) and 303 conditionally healthy (comparison group). Polymorphisms of the ApoE (rs429358), SIRT1 (rs7069102) genes were evaluated by PCR, the level of contaminants in the blood by inductively coupled plasma mass spectrometry, and neuroimmunogenesis parameters by ELISA.

Results. Schoolchildren with ANS pathology are characterized by an increased blood content of cadmium, lead, and arsenic, an elevation of the frequency of the C-allele and TC-genotype of the ApoE gene (rs429358), as well as the C-allele of the SIRT1 gene (rs7069102) (RR=1.23–1.83) relative to the comparison group. There was a significant increase in the expression of neuroimmunomediators acetylcholine and adrenaline (1.2 times) and a decreased expression of leptin and interleukin-17A (1.4–1.5 times) in relation to the indicators in healthy children. 

Limitations. The limited range of effect indicators used in this study.

Conclusion. The established polymorphism features of ApoE (rs429358), SIRT1 (rs7069102) genes in children reflect the risk of ANS disorders in conditions of low-level aerogenic HMs exposure. Indicators of neurotransmitter regulation, the C-allele of the ApoE (rs429358) and SIRT1 (rs7069102) genes are recommended to be used as indicators for the prevention and reduction of the risk of developing ANS diseases in adolescent schoolchildren under conditions of excessive bioexposure to cadmium, lead, and arsenic.

Compliance with ethical standards. The study was approved by the ethics committee of the Federal Scientific Center for Medical and Preventive Health Risk Management Technologies (Protocol No.14 of 14/03/2023). All participants and their legal representatives gave informed voluntary written consent to participate in the study.

Contribution:
Zaitseva N.V. — research design, editing;
Otavina E.A. — collection and processing of material, statistical processing, writing and editing of text;
Dolgikh O.V. — concept, research design, editing;
Kazakova O.A. — collection and processing of material, statistical processing, editing.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interest. The authors declare no conflict of interest.

Funding. The study had no sponsorship.

Received: September 4, 2025 / Accepted: October 15, 2025 / Published: December 19, 2025

Introduction. Long-term mercury exposure in the Usolye-Sibirskoye environment could create the preconditions for adverse health effects in children born in the area.

The objective. To assess the biochemical parameters in schoolchildren living in an environmentally sensitive area.

Materials and methods. A total of examined one hundred ninety one child aged of from 11 to 16 years was and divided into two groups: Group 1 (main group) – individuals with mercury excretion; Group 2 (comparison group) – individuals without it. All subjects were assessed for indicators reflecting the state of various types of metabolism. Comparison of groups were performed using the nonparametric Mann–Whitney U-test.

Results. Children in the main group had lower concentrations of total protein (p = 0.02) and albumin (p = 0.0002) in the blood serum compared to group 2. They were also characterized by higher concentrations of ceruloplasmin (p = 0.04), magnesium (p = 0.05), aspartate aminotransferase (p = 0.048). Children in group 1 had higher values of the atherogenic index (p = 0.0002), cholesterol proatherogenic fraction concentration (po = 0.02), as well as lower levels of the antiatherogenic fraction (p = 0.0002), apolipoprotein A1 (p = 0.003), ferritin (p = 0.04), vitamin D (p = 0.02), calcium, imbalance in the ratio of thyroid stimulating hormone (TSH), and free thyroxine (T4).

Limitations. The study’s limitations included adolescents aged 11 to 16 years, whose parents and they themselves permanently resided in Usolye-Sibirskoye and the surrounding area downwind of the Usolye-Sibirskoye industrial site.

Conclusion. Adolescents excreting mercury exhibited lower protein metabolism parameters, proatherogenic lipid metabolism, and signs of latent iron deficiency. They also had lower vitamin D levels, lower total calcium levels, lower TSH and T4 levels, and higher levels of thyroid peroxidase antibodies.

Compliance with ethical standards. The study was conducted in compliance with the ethical standards of the Helsinki Declaration (last revised) and Order No. 200n of Russian Federation Health Ministry the dated April 1, 2016. Conclusion of the local ethical committee of the East-Siberian Institute of Medical and Ecological Research No. 1 dated of December 21, 2023. All participants and their legal representatives gave informed voluntary written consent to participate in the study.

Contribution:
Kudaeva I.V. – the concept and design of the study, editing, writing text, final version approval;
Kurchevenko S.I. – statistical processing, writing text;
Lakhman O.L. – the concept and design of the study, final version approval;
Efimova N.V. – the concept and design of the study;
Kucherova N.G. – collection and processing of material, statistical processing;
Lysenko A.A., Starkova A.S., Prokhorova P.G., Rybakova A.P. – collection and processing of material.
All authors are responsible for the integrity of all parts of the manuscript.

Acknowledgment. The authors express their gratitude to I.V. Mylnikova, senior researcher at the Laboratory of environmental and hygienic research, for her assistance in managing the examination of children, and to O.V. Bukshina, research assistant at the Laboratory of analytical ecotoxicology and biomonitoring, for conducting research on determining mercury in urine.

Conflict of interest. The authors declare no conflict of interest.

Funding. The study had no funding and was performed within the framework of the funds allocated for exploratory scientific research of East-Siberian Institute of Medical and Ecological Research.

Received: October 24, 2025 / Revised: October 29, 2025 / Accepted: November 3, 2025 / Published: December 19, 2025

Ensuring food safety and quality being the key focus of state policy in the Russian Federation, aimed at preserving and strengthening public health. In the context of growing food losses and global challenges related to microbiological contamination, the emergence of resistant pathogens, and restrictions on the use of chemical fumigants, physical processing technologies, including food irradiation with ionizing radiation, are becoming particularly important. This review examines the technological foundations of food irradiation (radappertization, radurization, radicidation) in terms of the perspectives of hygiene and safety. Summary data on dose ranges for different food groups are provided.

The results of long-term biomedical studies and modern assessments are summarized: the impact of food irradiation on proteins, lipids, carbohydrates, vitamins, and bioactive substances, as well as data from the toxicological assessment of radiolysis products. Special attention is paid to classic experimental studies on several generations of laboratory animals and observations in human volunteers, which showed that with realistic doses and a balanced diet, irradiated food has no adverse effects on growth, development, reproduction, or lifespan. Modern toxicological and assessment studies of 2-alkylcyclobutanones and other radiolysis products are also considered.

The regulatory framework for the production of irradiated products in the USSR/Russia and abroad is analyzed. A list of products for which radiation processing was officially permitted by the USSR Ministry of Health is provided, indicating the purposes of processing and the maximum absorbed doses.

Promising areas for the regulated application of food irradiation in the Russian Federation are outlined (spices, dry ingredients, grain, meat and poultry, fish and seafood, fruit and vegetable products, specialized nutrition), along with priority tasks for assessing biomedical risks considering modern approaches. The necessity of a comprehensive approach to the hygienic regulation of food irradiation is substantiated, involving the harmonization of the regulatory framework with international standards, the development of identification methods, and digital traceability for irradiated products.

Contributions:
Popova A.Yu. – concept and article preparation;
Kuzmin S.V. – concept and article preparation, text writing;
Rusakov V.N. – material collection and processing, text writing, editing.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version

Conflict of interest. The authors declare no conflict of interest.

Funding. The study had no sponsorship.

Received: May 29, 2025 / Revised: November 20, 2025 / Accepted: November 25, 2025 / Published: December 19, 2025

Introduction. The mining industry is one of the most hazardous sectors, where personnel is exposed to complex occupational hazards.

Aim of the study. To assess the actual nutritional status, nutritional status, and biochemical status of mine miners to support personalized prevention programs.

Materials and Methods. The study included seventy five male mine miners assigned to physical activity group 3 (physical activity index of 1.9). The average age of the participants was 56.6 ± 3.4 years, and the average occupational experience was 23.4 ± 2.3 years. Dietary frequency analysis, anthropometry (BMI), and blood biochemistry were used.

Results. Adequate protein intake was recorded in 94% of workers, while 6% had a deficiency (between 5% and 7% below the norm). Fat intake was adequate in only 25% of individuals. Fat deficiency was detected in 7% of the surveyed, while excess fat was found in 68%. Adequate carbohydrate intake was recorded in 40% of the surveyed; excess consumption was recorded in 58%, while deficiency was found in 2%. Dietary patterns were disrupted: 77.5% overindulged at dinner, while 64% had irregular meals. More than half of the workers (52%) were overweight or obese. Biochemical analysis confirmed a high prevalence of dyslipidemia: elevated LDL cholesterol (in 66.7% of the surveyed) and total cholesterol (in 54.3%).

Limitations. This study is limited by the age of the surveyed and the type of their occupational activity.

Conclusion. The study revealed that the key nutritional deficiencies among miners include excess calories from fats and carbohydrates, some vitamin (A, B1, B2), and mineral (Ca, Mg) deficiencies, eating disorders (irregular meals, excessive dinners, alcohol consumption), and a high prevalence of overweight, obesity, and atherogenic dyslipidemia. The data obtained formed the basis for the development of specialized diets.

Compliance with ethical standards. This study was conducted in compliance with biomedical ethical standards and approved by the Ethics Committee of the F.F. Erisman Federal Scientific Center of Hygiene of Rospotrebnadzor (Protocol No. 1 dated March 1, 2024). All participants provided informed, voluntary written consent to participate in the study.

Contributions:
Kuzmin S.V. – article concept and preparation,
Setko A.G. – article concept and preparation, writing;
Rusakov V.N. – material collection and processing, writing, editing.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version

Conflict of interest. The authors declare no conflict of interest.

Funding. The study was conducted as part of the industry research program in hygiene No. 121090800070-6.

Received: September 11, 2025 / Revised: October 27, 2025 / Accepted: November 3, 2025 / Published: December 19, 2025

Introduction. Synthetic food dyes (FD) have a number of advantages over natural ones and are increasingly used in the production of preparations and food products, which in turn increases attention to the issue of their safety. The safety assessment of FD includes testing for mutagenicity in “in vitro” and “in vivo” tests.

The aim of the work. To determine the mutagenic activity of the four most common synthetic FDs from the azo dyes (PaD) group in food products on the domestic market.

Materials and methods. The mutagenic activity of Sunset Yellow FCF, Tartrazine, Ponceau 4R, and Azorubine was assessed in the preincubation version of the Ames test on test strains of S. typhimurium TA1535, TA100, TA98, TA97, TA102 in the dose range of 8–5000 µg/plate with the addition of riboflavin to the microsomal activating mixture.

Results. No dependence of the frequency of revertant colonies on the concentration of the studied dyes was found, and the excess of the average number of colonies per dish in the experimental variants over the control was less than twofold, which indicates the absence of a mutagenic effect of the studied FaD samples.

Limitations. The study is limited to examining the mutagenicity of food azo dye samples in a single test that takes into account gene mutations in bacteria.

Conclusion. Sunset Yellow FCF, Tartrazine, Ponceau 4R, and Azorubine did not induce gene mutations in the Ames test.

Compliance with ethical standards. The study does not require the submission of a conclusion of the biomedical ethics committee or other documents.

Contribution:
Akhaltseva L.V. – search, analysis of literature data, setting up experiments, writing the article;
Yurchenko V.V. – analysis of literature data, editing the article;
Nikitina T.A. – search for literature sources, setting up experiments;
Mamonov R.A. – research concept, editing the article;
Vodyanova M.A. – editing the article.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interest. The authors declare no conflict of interest.

Funding. The work was carried out within the framework of the state task «Complex system for assessing the genotoxicity of food additives» Centre for Strategic Planning of the Federal medical and biological agency.

Received: May 29, 2025 / Revised: July 1, 2025 / Accepted: October 15, 2025 / Published: December 19, 2025

Introduction. Assessment of the quality of drinking water and its impact on human health is of primary importance for regions with arid and semi-arid climates, due to the limited availability of water of acceptable quality.

Objective of the study. Conduct a hygienic assessment of the quality of drinking water in the territory of a number of municipal districts of the Republic of Kalmykia and assess the impact of the quality of drinking water on the health of the population.

Materials and methods. Drinking water samples were collected from consumer taps in the Republic of Kalmykia, in accordance with the Federal requirements according to GOST 56237–2014. Data on population morbidity for the period from 2018 to 2024 were provided by the Medical Information and Analytical Center of the Ministry of Health of the Republic of Kalmykia. The assessment of non-carcinogenic risk to public health when consuming drinking water was carried out in accordance with R 2.1.10.3968–23.

Results. The quality of drinking water supplied to the population of the Republic of Kalmykia does not meet hygienic standards in Sarpinsky, Ketchenerovsky, and Tselinny districts, as well as in the city of Elista for such indicators as sodium, magnesium, boron, chloride, and sulfate ions. Consumption of water supplied from the Yergeni artesian basin creates a risk to public health at a minimum level of exposure. At the same time, no connection has been found between the incidence of diseases in the population and the quality of drinking water.

Limitations. The limitations of this work are related to the relatively small sample sizes in the study.

Conclusions. The quality of drinking water from the centralized water supply system in the studied areas of the Republic of Kalmykia was found to be inconsistent with hygienic standards, which creates a risk for public health. However, no connection was found between the incidence in the population and the quality of drinking water, which may be due to the small proportion of the population using drinking water from centralized water supply systems for drinking needs.

Compliance with ethical standards. The study was approved by the local ethics committee of the Saratov Medical Scientific Center of Hygiene of the Federal Scientific Center of Medical and Preventive Technologies for Health Risk Management of the Population (minutes of meeting No. 21 of 09/01/2022), conducted in accordance with the generally accepted scientific principles of the Helsinki Declaration of the World Medical Association (2013 edition).

Contribution:
Erdniev L.P. – collection and processing of material, writing text;
Mikerov A.N. – the concept and design of the study, editing;
Moiseeva Ye.M. – editing;
Kuzyanov D.A. – processing of results, writing text.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interest. The authors declare no conflict of interest.

Funding. The study had no sponsorship.

Received: September 3, 2025 / Revised: September 9, 2025 / Accepted:  November 3, 2025 / Published: December 19, 2025

Introduction. Obese patients receive higher radiation doses during interventional procedures compared to patients with normal body weight. The difficulty of setting up interventional x-ray system taking into account individual anthropometric features in obese patients affects the implementation of the principle of dose optimization.

The aim of the study. To calculate and evaluate the relationship between dose-time characteristics of interventional procedures and individual anthropometric parameters in patients.

Materials and methods. The data of the performed interventional radiology procedures in patients from the logs of interventions were used in the study. Analyzed anthropometric parameters in patients included height, body weight, body mass index (BMI), body surface area (BSA). Multiple linear regression equations were proposed to predict the effective dose in patients with different anthropometric characteristics.

Results. Diagnostic and therapeutic procedures were found to differ significantly in terms of the main dose parameters. The structure of patients who underwent coronary interventions was dominated by those with excess body weight (43.5%) and average body surface index (52.1%). At the same time, in patients with overweight and obesity of the degree I and III the product of dose per area was, respectively, 1.8 and 2.4 times higher than in patients with normal body mass index. Statistically significant differences were obtained for BSA, whereas BMI showed no such differences. The multiple regression model excluded BMI, mass and height due to low informativeness for dose prediction, confirming the need to consider individual BSA values when optimizing radiation dose.

Limitations. Radiation doses were not determined by direct dosimetry, other anthropometric and somatoscopic parameters were not recorded.

Conclusion. The results of the study emphasize the importance of individual calculation of effective dose and adaptation of equipment parameters taking into account the anthropometry of the patient to reduce radiation exposure.

Compliance with ethical standards. The trial does not require the submission of a biomedical ethics committee opinion or other documents.

Contribution:
Sukhov V.A. — the concept of the study, collection and processing of material, statistical processing, writing text;
Lantukh Z.A., Zhernov Yu.V. — editing;
Shcherbakov D.V. — design of the study, processing of material, editing.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Funding. The work was carried out within the framework of the state assignment with the code “Risk indicator 25-27”, registration number EGISU 125032604484-5.

Conflict of interest. The authors declare no conflict of interest.

Received: July 4, 2025 / Accepted:  November 3, 2025 / Published: December 19, 2025

Introduction.Today, due to the growth of idiopathic male infertility, the problem of the impact of chemical and physical factors on the reproductive function in men remains very relevant.Studies on the effect of radiation and hexavalent chromium on male fertility in small doses deserve special attention.Literature data on gonadotoxicity and embryotoxicity under exposure to factors in small doses are very contradictory.

Materials and methods. The experimental study was conducted on sexually mature BALB/c mice and Wistar rats of both sexes (a total of 189 animals). The animals were divided into groups according to the received dose of training and potassium dichromate. In mice, group 1 was a control, group 2 consisted of males who received a dose of 0.25 Gy, and group 3 received a dose of 0.5 Gy. In rats, group 1 was a control, group 2 consisted of males who received potassium dichromate (K₂Cr₂O₇) at a dose of 0.028 mg/kg, and group 3 – at a dose of 0.28 mg/kg for 48 days. The state of spermatogenesis was assessed in smears from testicular cell homogenate. To analyze embryonic losses, experimental animals were mated with intact females.

Results. Analysis of the testicles of animals after irradiation and chromium intoxication revealed the following: a 20% decrease in the relaxation index, an increase in multinucleated cells by 40% (dose 0.5 Gy) and 25% (dose 0.28 mg/kg), in aberrant germ cells by 1.5–2 times (dose 0.028 mg/kg and 0.5 Gy, respectively), and an almost 2-fold increase in the number of spermatids with micronuclei. The number of spermatozoa with abnormal heads increases: by 15–20% with irradiation and by 1.5–2 times with chromium intoxication. Mating of experimental males with intact females indicates an increase in the overall embryonic mortality in fetuses by 1.5–2 times with chromium intoxication.

Limitations. In the study, when using the quantitative cytological express method in assessing spermatogenesis disorders under the influence of radiation and xenobiotics in small doses, there are no data on remote effects (90–120 days), which would allow determining the prognostic significance of these indicators in solving reproductive problems.

Conclusions. For the first time, based on quantitative, morphological indicators, the degree of spermatogenesis impairment and the level of embryonic losses during irradiation and chromium intoxication in low doses were shown. The most pronounced degree of spermatogenesis impairment during chromium intoxication leads to a higher level of embryonic mortality.

Compliance with ethical standards. The experimental study was approved by the Bioethics Committee of the Institute of Plant and Animal Ecology of the Ural Branch of the Russian Academy of Sciences (protocol No. 13 dated 03/12/2025).

Conflict of interest. The authors declare no conflict of interest.

Funding. The study was carried out within the framework of State Assignment to Institute of Plant and Animal Ecology (No. 122021000085-1).

Received: April 28, 2025 / Accepted: June 26, 2025 / Published: December 19, 2025

Introduction. Assessing the human health risks associated with exposure to chemicals is the foundation of modern preventive medicine and environmental policy. However, any risk assessment model relies on a number of assumptions, simplifications, and limited data. This is where the problem of “uncertainty factors” arises, many of which are often left outside the scope of standard calculations. Unaccounted for, their contribution can lead to a significant underestimation or, less commonly, overestimation of the actual risk, jeopardizing the effectiveness of management decisions and the protection of public health.

Materials and methods. Chemico-analytical studies were aimed at identifying a wide range of pollutants in various types of water. The comparison of chemical substances and the analysis of the obtained results were performed using the Kramer method, including the Threshold of Toxicological Concern (TTC) approach.

Results. The conducted studies confirmed the primary challenge for the centralized water supply systems in the region to be producing drinking water that meets regulatory standards when treating low-mineralized water with a high content of natural organic compounds. The findings demonstrate the drinking water in the distribution network of the city of N. in the Murmansk Region to be unsafe. This is due to both the chloroform content, which exceeds the Maximum Allowable Concentration (MAC) by 1.5 times, and the level of 3-chlorobutan-2-ol, which surpasses the Threshold of Toxicological Concern (TTC) by 3.5 times.

Limitations. The use of the TTC method is currently only possible for scientific purposes.

Conclusion. The TTC principle offers a rational approach to managing the risks of chemical substances for which complete toxicological information is lacking. It establishes a level of human exposure considered safe, below which the risk of adverse effects is deemed negligible, even in the absence of full data on the specific compound. Thus, the TTC principle provides a tool for the comparative assessment of different water sources or treatment technologies based on an integral indicator of chemical safety. This approach reduces toxicological uncertainty and provides specific quantitative benchmarks for further regulatory action.

Compliance with ethical standards. The study does not require the conclusion of the Biomedical Ethics Committee.

Contribution:
Alekseeva A.V. – concept and design of the study, writing the text, collecting material and processing data, editing, approval of the final version of the article, responsibility for the integrity of all parts of the article;
Rakhmanin Yu.A. – concept and design of the study, editing;
Malysheva A.G. – writing the text, collecting material and processing data.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interest. The authors declare no conflict of interest.

Funding. The study had no sponsorship.

Received: October 14, 2025 / Accepted: November 3, 2025 / Published: December 19, 2025

The aim of the study. A multi-criteria assessment of the medical and demographic situation in the territorial units of the Republic of Bashkortostan. The motivation of the study is a necessity to diagnose emerging problems and evaluate the effectiveness of social programs and policies carried out in municipalities.

Materials and methods. The information base of the study is a data published by the Medical Information and Analytical Center of the Republic of Bashkortostan. Fourteen indicators, characterizing medical resources and medical efficiency of healthcare, population health and the demographic situation in 2022 were in use. Calculations were carried out for  sixty two territories, including 54 municipal districts and 8 urban districts. TOPSIS was used as a multi-criteria assessment method, the weights of the indicators were determined using the entropy weighting method.

Results. According to the calculations, the most favorable medical and demographic situation is in the industrially developed territories of the Republic (Ufa, Sterlitamak, Oktyabrsky, Kumertau, Tuymazinsky, Meleuzovsky and Birsky districts). Three northern territories of the Republic of Bashkortostan (Karaidelsky, Duvansky and Kiginsky districts) also fall into this category; they have a highly developed recreational component and a large inter-district medical center (Mesyagutovo village). Two territories (Abzelilovsky and Zianchurinsky districts) fall into this category largely due to the high birth rate, traditional for these rural areas. The most unfavorable medical and demographic situation is in the northwestern territories, as well as the Kuyurgazinsky, Sharansky, Arkhangelsky and Belokataysky districts, which are very remote from the capital and are leaders in terms of high natural population decline.

Limitations. The calculations were performed based on data for 2022 only. Performing calculations for several periods would allow assessing the stability of the estimates obtained. The set of indicators included in the analysis also requires further clarification.

Conclusion. The findings are useful for making targeted decisions in the field of regional healthcare system management.

Compliance with ethical standards. The conclusion of the biomedical ethics committee or other documents (in Russian and English) is not required.

Contribution:
Rakhmanin Yu.A. — the concept and design of the study, editing;
Askarov R.A. — the concept and design of the study, editing;
Frants M.V. — collection and processing data, editing;
Lakman I.A. — writing text, editing.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interest. The authors declare no conflict of interest.

Funding. The study had no sponsorship.

Received: July 30, 2025 / Revised: September 24, 2025 / Accepted: November 3, 2025 / Published: December 19, 2025

Introduction. The most important task of monitoring environmental objects is the control of physiologically significant mineral components in drinking water. In ionochromatographic analysis of a mixture of anions in an aqueous sample, they can be divided into micro- and macro-components. Chromatographic determination of such toxicologically significant micro-components as nitrites, bromides, and iodides is difficult or impossible with large excesses of macro-components: chlorides, nitrates, and sulfates. Simultaneous sequential use of conductometry and amperometry makes it possible to effectively solve this complex analytical problem and obtain chromatographic results when analyzing a multicomponent sample in a single file.

Materials and methods. The studies were performed using the «Steyer» chromatographic system with ICSepAN2 (USA) and Aquilon A1 (RF) anion columns and amperometric and conductometric detection. Standard and exclusive capillary background suppression was used in the research. The objects of research were water samples (full-scale and model) with different concentration ratios for the anions to be determined.

Results. A new option of ionochromatographic method has been developed for the analytical control of anions in water samples with different concentrations of micro- and macro components. Consistent use of conductometry and amperometry combined with capillary exclusive background suppression has made it possible an effective detection of toxic anions such as nitrites, bromides, and iodides with presence of thousands of times the excess of chlorides, nitrates, and sulfates. At the same time, in a single file with two-channel recording of conductometric and amperometric signals, the possibility of obtaining a single chromatographic picture with a single aliquot input into the chromatographic system is shown.

Limitations. When significant amounts of nitrites and bromides (more than 5 mg/dm) are present in the samples at the same time, their chromatographic separation is difficult due to their similar retention times. However, the authors have not encountered such samples in their research on monitoring water bodies in the environment.

Conclusion. A new use case for ion chromatography (IC) is proposed as a method for monitoring the anionic composition of water, including sequential conductometric and amperometric detection as the eluent passes through the chromatographic system. The method makes it possible to determine the microconcentrations of toxic components (nitrites, bromides, iodides) against the background of a thousand fold excess of macro components. At the same time, two-channel fixation of chromatographic signals allows obtaining a complete chromatographic picture of both micro and macro components of the sample.

Compliance with ethical standards. the conclusion of the biomedical ethics committee or other documents (in Russian and English) is not required.

Contribution:
Abramov E.G. – collection and processing of material, statistical processing, text writing, research concept, editing;
Kiryakova N.A. – collection and processing of material, text correction;
Zhernov Yu.V. – editing.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interest. The authors declare no conflict of interest.

Funding. The study had no sponsorship.

Received: March 19, 2025 / Revised: July 22, 2025 / Accepted: November 3, 2025 / Published: December 19, 2025

Introduction. The use of deicing materials (DMs) in cities is a significant factor in chemical pollution of the environment, which makes it a priority to assess their impact on public health. In this paper, we propose an original approach to studying the chemical composition of DMs using the electrospray ionization mass spectrometry (ESI-MS) method, which makes it possible to identify the salt composition and functional additives of DMs by characteristic ions.

Materials and methods. As standard samples there were used aqueous saline solutions of the inorganic salts including sodium chloride, calcium chloride, and magnesium chloride. The set of investigated commercial chloride samples of PGM included solid and liquid samples based on sodium and calcium chlorides, as well as a liquid sample based on magnesium chloride. During sample preparation, liquid-liquid extraction was performed by mixing the DMs sample (a saturated aqueous saline solution) with acetonitrile. For composition analysis, an Agilent 6430 mass-selective detector with a quadrupole mass analyzer and an electrospray ionization source was used. To identify inorganic salts, an algorithm for comparing the mass spectra of the sample and standards with a quantitative assessment of their similarity was applied.       

Results. At the qualitative analysis it has been shown to be possible to determine the main components of DMs presented in the form of salts of sodium, calcium and magnesium chloride. The study presents a new approach to the determination of these components in the composition of chloride DM samples. At the same time, a qualitative assessment of the content of organic compounds in the composition of DMs is carried out on the base on the data obtained.

Limitations. Evaluation of the quantitative characteristics of the DMs component composition for different inorganic compounds when determining the degree of similarity of their mass spectra may be difficult due to the effect of suppression by NaCl ions in the case of their presence in the DMs composition.

Conclusion. The study’s results suggest that the ESI-MS method can be regarded as one of the modern techniques for the rapid analysis of the chemical composition of DMs chloride. This method holds promise for implementation in both laboratory and monitoring studies aimed at identifying potential risks associated with the adverse effects of DMs on environmental objects and public health in a timely manner.

Compliance with ethical standards. The conclusion of the biomedical ethics committee or other documents is not required.

Contribution:
Sbitnev A.V. — conducting the experimental part of the study, collecting and processing data; discussion and editing of the text;
Vodianova M.A. — the idea, concept and design of the study; discussion and editing of the text;
Streletskiy A.V. — the idea, concept and design of the study; conducting the experimental part of the study, collecting and processing data; writing the text;
Yudin S.M. — the idea, concept and design of the study.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interest. The authors declare no conflict of interest.

Funding. The work was completed within the framework of the state task:. reg. No 388-00099-23-02, No 123040500002-3.

Received: March 6, 2025 / Revised: June 16, 2025 / Accepted: , 2025 / Published: December 19, 2025

Introduction. Modern environmental monitoring requires effective methods for detecting and identifying new potentially hazardous anthropogenic contaminants, especially those not subject to standard control. High-performance liquid chromatography with tandem mass spectrometry (HPLC-MS/MS) is a promising tool for non-target screening of micropollutants in aquatic environments.

Materials and methods. A non-target screening approach using HPLC-MS/MS was applied. This involved recording mass spectra of major components in water samples (wastewater before and after treatment, drinking water) followed by comparison of experimental fragmentation spectra with reference databases (MassBank, NIST) using spectral similarity algorithms.

Results. The non-target screening method using HPLC-MS/MS enabled the detection and tentative identification of six organic compounds in wastewater samples with varying degrees of resistance to treatment. Caprolactam and 3-cyclohexyl-1,1-dimethylurea were found to be the most persistent, with removal efficiencies of 40% and 31%, respectively, indicating their high resistance to standard water treatment technologies. Other identified compounds, including lauryldiethanolamide, demonstrated removal efficiencies ranging from 93% to 98%. Identification was confirmed by matching experimental fragmentation spectra with MassBank and NIST databases. Probable sources of formation and discharge of these contaminants, along with associated environmental risks, were established.

Limitations. Final confirmation of identity and accurate quantification requires additional targeted analysis using certified reference standards.

Conclusion. The presented non-target screening approach based on liquid chromatography with tandem mass spectrometry proved effective for detecting and tentatively identifying new potentially hazardous anthropogenic contaminants in various water samples. A key result of this work was the identification of two persistent organic compounds in wastewater – caprolactam and 3-cyclohexyl-1,1-dimethylurea – which exhibited the lowest removal efficiency.

Compliance with ethical standards. The study does not require the conclusion of the Biomedical Ethics Committee.

Contribution:
Streletskiy A.V. — the concept and design of the study, experimental work, collection and processing of material, statistical processing, writing a text;
Filimonova E.I — experimental work, collection and processing of material.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interest. The authors declare no conflict of interest.

Funding. The work was completed within the framework of the state task (“Monitoring”, “Chemical Indicators 25-27”).

Received: August 15, 2025 / Accepted: November 3, 2025 / Published: December 19, 2025

Introduction. Quantitative determination of fatty acids (FA) in biological fluids allows assessing of dietary intake, their role in biochemical processes, physiological functions, such as normal brain and heart function.

Objective. To develop a rapid method for the quantitative determination of fatty acids in urine based on chromatograph mass spectrometry analysis for assessing nutritional status.

Materials and Methods. Preparation of urine samples for chemical analysis of fatty acids included alkaline methylation by treating the biosample with potassium methylate, which enabled rapid and quantitative methylation of both free fatty acids and triglycerides. A capillary column with an FFAP with a programmable heating mode of 70–245 °C was used to separate fatty acid esters. The quadrupole mass spectrometer with electron ionization.

Results. The developed rapid method based on chromatographic mass spectrometry (CMS) allows analysing the fatty acid composition in urine, identifying 34 of their derivatives in a concentration range from 0.004 to 9.975 µg/cm³. The conducted studies revealed the following maximum fatty acid concentrations: eicosatrienoic acid (3.608 µg/cm³) in 100% and tricosanoic acid (0.351 µg/cm³) in 91.2% of healthy individuals.

Limitations. Study limitations may be related to the need to exclude the determination of an incomplete spectrum of fatty acids, such as hydroxy acids.

Conclusion. Metabolomic analysis of urine for FA composition may be a promising direction for assessing nutritional status and identifying biomarkers characterizing changes in alimentary factors.

Compliance with ethical standards. The study was approved by the local ethics committee of the Rospotrebnadzor’s Federal Scientific Center for Medical and Preventive Health Risk Management Technologies (the meeting protocol No. 3 dated March 28, 2025). All participants gave informed voluntary written consent to participate in the study.

Contribution:
Nurislamova T.V., Lear D.N. – concept, study design, editing;
Terentyev G.I. – collection and treatment of material, analysis of obtained data, writing the text;
Subbotina D.Yu., Yakusheva E.A. – collection and treatment of material, analysis of obtained data;
Suvorov D.V. – collection and treatment of material.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interest. The authors declare no conflict of interest.

Funding. The study had no sponsorship.

Received: September 9, 2025 / Revised: October 24, 2025 / Accepted: November 3, 2025 / Published: December 19, 2025

Introduction. A promising direction of nanotoxicology is the study of the effect of gadolinium nanoparticles on the body, which is possible using high-molecular compounds, for example, Siberian larch arabinogalactan, which has a stabilizing effect on nanoparticles.

Materials and methods. As part of experimental studies, subacute (within 10 days) intragastric effects were carried out on outbred sexually mature male white rats (sixty four individuals) of gadolinium nanocomposite encapsulated in a natural polymer matrix of arabinogalactan at a dose of 500 µg/kg body weight and 5000 µg/kg body weight, respectively. The examination took place in 2 stages: immediately after the end of the seed (early period) and 6 months after the end of the exposure (long-term period). The work used a set of studies aimed at determining gonadotoxicity – histological examination of the tissues of the spermatogenic epithelium, morphometrically determined the general indicator of functional activity of the testes – the index of spermatogenesis.

Results. Based on the conducted experimental studies, there has been established gonadotoxic effect of gadolinium nanoparticles on the reproductive system in male rats, expressed in the destruction of the germinal epithelium of the seminal tubules with a violation of the normal process of spermatogenesis with the administration of both doses of the studied nanocomposite, while in the long term the indicators do not return to normal. Also gadolinium nanoparticles have been established to be able to penetrate the hemato-testicular barrier, accumulating in testicular tissues.

Limitations. The number of animals and the set of techniques is sufficient to study the effects of gadolinium nanoparticles encapsulated in the polysaccharide arabinogalactan on the structural and functional state of testicular tissue.

Conclusion. With subacute exposure to gadolinium nanoparticles encapsulated in an arabinogalactan matrix, there has been established their gonadotoxic effect on the male reproductive system, expressed by structural and functional changes in testicular tissue.

Compliance with ethical standards. The work was carried out in accordance with the protocol of experimental research, the principles set out in the European Convention for the Protection of Vertebrate Animals Used for Experiments or Other Scientific Purposes ETS No. 123, GOST 33215-2014 “Guidelines for the care and care of laboratory animals. Rules of equipment of premises and organization of procedures”, Recommendations for euthanasia of experimental animals: Part 1, Part 2. Permission was obtained from the Local Ethics Committee to conduct research (Protocol No. 8 dated 12/15/2023).

Contribution:
Novikov M.A. – concept and design of research, data processing, editing, writing text;
Titov E.A. – concept and design of research, editing;
Pankova A.A. – collection of material and data processing;
Lisetskaya L.G. – data processing;
Sosedova L.M. – concept and design of research, editing, writing text.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Acknowledgment. The team of authors would like to thank Yu.Y. Titova, Head of the Laboratory of functional nanomaterials of the Federal Research Center “A.E. Favorsky Irkutsk Institute of Chemistry’, the Siberian Branch of the Russian Academy of Sciences for her help in conducting research to determine the dimensional characteristics of gadolinium nanoparticles.

Conflict of interest. The authors declare no conflict of interest.

Funding. The study was carried out within the framework of the state assignment of the East Siberian Institute of Medical and Environmental Research.

Received: September 12, 2025 / Accepted: November 3, 2025 / Published: December 19, 2025

Introduction. In recent decades, wildfires have become more frequent and intense in many fire-prone areas. However, the mechanisms of smoke cytotoxicity at the cellular level are poorly understood. The study of peat smoke extract (PSE) cytotoxicity in fibroblasts is an important model for studying the acute and chronic effects of smoke exposure.

Materials and methods. The cytotoxicity of peat smoke was assessed in a series of in vitro experiments using PSE in 8 dilutions (12.5, 25, 37.5, 50, 62.5, 75, 87.5 and 100%) on 3T3-SV forty mouse embryonic fibroblasts. The cytotoxic effect was assessed after 24-hour incubation by determining the concentration of lactate dehydrogenase (LDH) in the culture medium and performing the MTT test; a morphological assessment of the cells was given.

Results. The results of the study indicate that PSE primarily leads to a decrease in the metabolic activity in fibroblasts, as evidenced by a lower value of the mean inhibitory concentration (IC50) (53.6%) calculated by the MTT test. When assessing the cytotoxic effect of PSE in the LDH test, a sharp decrease in cell viability was observed at its concentration above 62.5%, the IC50 value in this test was 57.7%.

Limitations. The study is limited to the investigation of the cytotoxicity of PSE on the 3T3-SV 40 cell culture using morphological assessment, MTT test and determination of LDH concentration.

Conclusion. As a result of the conducted studies, an assessment of the impact of peat smoke on fibroblasts in vitro was carried out, with the help of which a primary toxicological characteristic of PSE was given.

Compliance with ethical standards. The study was approved by the local ethics committee of the East-Siberian Institute of Medical and Ecological Research (Protocol No.7 of 12/15/2023), conducted in accordance with the European Convention for the Protection of Vertebrate Animals Used for Experiments or for Other Scientific Purposes (ETS N 123), Directive 2010/63/EC of the European Parliament and the Council of 09/22/2010 on the protection of animals used for scientific purposes.

Contribution:
Abramova V.A. – concept and design of research, data collection and processing, statistical data processing, text writing, editing;
Vokina V.A. – concept and design of research, data collection and processing, statistical data processing, text writing;
Sosedova L.M. – concept and design of research, editing.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interest. The authors declare no conflict of interest.

Funding. The work was carried out according to the research plan within the framework of the state task.

Received: July 20, 2025 / Revised: October 3, 2025 / Accepted: October 15, 2025 / Published: December 19, 2025

Introduction. The metabolic syndrome (MS) is one of the manifestations of symptoms combination of endocrine and cardiovascular diseases. Its estimated incidence in 2005 was approximately 25% of the world population.

The aim of the study. To determine the prevalence of metabolic syndrome and its components among Irkutsk region residents.

Materials and methods. Seven hundred sixty nine men and 390 women aged 30 to 69 years were examined. Body mass index, glucose levels, and lipid metabolism parameters were calculated for all subjects. Relative abundance was compared using confidence intervals (CI).

Results. MS in the examined sample occurred in 45% (95% CI 42–49) of men and 61% (95% CI 57–66) of women (p<0.05). The prevalence of abdominal obesity among the cohort representatives was 57% (95% CI 54–61) and 79% (95% CI 75–83) in males and females, respectively. In women, the incidence of the cholesterol proatherogenic fraction was statistically significantly higher than in men: 82% (95% CI 76–86) and 70% (95% CI 65–75), respectively. The second most common was elevated triglyceride levels. Its frequency of occurrence was statistically significantly higher in men. The third place was occupied by a criterion associated with certain carbohydrate metabolism disorders. This criterion was statistically significantly more often recorded in females. Low concentration of the cholesterol antiatherogenic fraction as an additional criterion of MS ranked fourth in frequency of occurrence and did not statistically differ in men and women.

Limitations. Individuals living in the Irkutsk region. Subjects aged 30–69 years with no history of diabetes, stroke, or heart attack.

Conclusion. The prevalence of MS in the Irkutsk region is 45–61% for men and women, respectively, which is higher than the global average.

Compliance with ethical standards. The study was conducted in compliance with the ethical standards of the Helsinki Declaration (last revised). Conclusion of the local ethical committee of the East-Siberian Institute of Medical and Ecological Research No. 2 dated December 21, 2023. All participants gave informed voluntary written consent to participate in the study.

Contribution:
Kudaeva I.V. – the concept and design of the study, editing, statistical processing, writing text;
Kucherova N.G. – collection and processing of material, statistical processing;
Lysenko A.A. – collection and processing of material;
Rybakova A.P. – collection and processing of material.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

Conflict of interests. The authors declare no conflict of interests.

Funding. The study had no funding and was performed within the framework of the funds allocated for exploratory scientific research of East-Siberian Institute of Medical and Ecological Research.

Received: October 3, 2025 / Revise d: November 1, 2025 / Accepted: November 3, 2025 / Published: December 19, 2025