Hygiene and Sanitation

Many active ingredients in pesticides are mixtures of isomers. When ingested by humans, crops, or exposed to environmental factors, such a mixture can be completely or partially transformed into the corresponding metabolites over a period of time. Such metamorphoses of mixture components often lead to numerous questions when establishing regulatory requirements for safety indicators and, on the other hand, to difficulties in documenting and presenting research results. This article discusses this issue using the organochlorine pesticide dichlorodiphenyltrichloroethane (DDT) as an example. Its residues in food products are one of the most closely monitored safety indicators in the world, subject to mandatory declaration on all food products in the Russian Federation. Domestic and international approaches to standardizing DDT isomers and metabolites are described. Several methods for determining DDT, ensuring compliance with regulatory requirements, are considered. The main challenges of both DDT standardization and methodological support are identified and outlined. These challenges stem from the ambiguity of the mandatory safety indicator for any food product, defined in CU TR 021/2011 and other technical regulations of the Eurasian Economic Union (EAEU) for food products and food raw materials as “DDT and its metabolites.” An analysis of regulatory requirements for food safety set out in national, interstate, and international documents was conducted using publicly available materials, including technical regulations of the Eurasian Economic Union (EAEU) for food products and food raw materials, documents of the Codex Alimentarius Commission, the European Union, the US Food and Drug Administration (FDA), and the legislation of Japan, Australia, and the People’s Republic of China.

Contribution:
Rakitsky V.N. – concept and design of the study;
Dobreva N.I., Fedorova N.E. – concept and design of the study, collection and processing of material, writing text, editing;
Suslova A.V. – 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 study had no sponsorship.

Received: April 23, 2026 / Revised: June 15, 2026 / Accepted: July 1, 2026 / Published: August 14, 2026

Introduction. In women in the Russian Federation, malignant neoplasms of the breast are the leading oncological pathology, which is a multifactorial disease requiring a comprehensive approach to study.

The aim of the study was to study the features of breast cancer incidence and mortality due to it in women of an industrial city with high level of air pollution.

Materials and methods. The study of breast cancer incidence and mortality among female residents of Novokuznetsk for 2014-2025 was based on an analysis of materials from the territorial Cancer Registry 6FB for the Kemerovo region with statistical processing using the MS Excel package. Gross emissions into the atmosphere and average annual concentrations of carcinogenic pollutants were assessed on the base of official reports for the period 2014–2024. Maximum permissible concentrations of substances were assessed according to the Sanitary Rules and Norms 1.2.3685–21. There were were examined one hundred fifty nine women, 104 of whom had been diagnosed with breast cancer and 55 had no suggestion for cancer of the breast. Using the polymerase chain reaction method, variants of the CYP1A1*2A (rs4646903) gene of the first phase of the xenobiotic biotransformation system were identified in all subjects examined.

Results. In Novokuznetsk, over the past 10 years, there was an increase in the incidence of breast cancer and mortality of it among women. Between 2014 and 2025, the number of women with firstly proven diagnosis increased by 23.4%, while the proportion of early detection of the disease at stage I raised by 16%. The total individual carcinogenic risk corresponded to the permissible (acceptable) level in 2017, 2018, and 2020, and to the alarming level in the remaining years. A positive correlation was found between the incidence of cancer and the total volume of gross emissions into the city’s atmosphere (r_s = 0.45), as well as average annual concentrations of formaldehyde (r_s = 0.19), and benzopyrene (r_s = 0.07). A weak positive correlation was revealed between the number of deaths due to breast cancer and average annual concentrations of benzopyrene. A statistically reliable association was shown between the AA genotype (χ² – 4.04; OR – 2.06) of the phase 1 detoxification gene – CYP1A1*2A (rs4646903) with the risk of breast cancer.

Limitations of the study were determined by the lack of data on average annual carbon (soot) concentrations since 2022 and the need to further increase the sample for genetic studies.

Conclusion. Reducing the incidence and mortality rates of breast cancer requires comprehensive regional scientific approaches, including epidemiological, medico-demographic, hygienic, clinical, and molecular-genetic studies as the basis for integrated information for the elaboration and implementation of early diagnosis and prevention programs for oncological diseases, with a focus on regions with environmental disadvantage.

Compliance with ethical standards. The study was approved by the local Ethics Committee of the Federal State Budgetary Scientific Institution “Research Institute for Complex Problems of Hygiene and Occupational Diseases” (Minutes of meeting No. 2, § 2 of March 11, 2025), and was conducted in accordance with the commonly accepted scientific principles of the Helsinki Declaration of the World Medical Association (2013 edition).

Contribution:
Mikhailova N.N. – concept and design of the study, editing;
Kislitsyna V.V. – collection and processing of material, writing the text;
Baran O.I. – collection and processing of material, writing the text;
Gulyaeva O.N. – collection and processing of material, writing the text;
Ulanova E.V. – processing of material;
Chifranova M.V. – collection of material;
Dolgikh S.A. – collection 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: April 24, 2026 / Accepted: July 1, 2026 / Published: August 14, 2026

Introduction. Heart diseases are the leading cause of death among miners (>60%). Between 2000 and 2016, 1,797 acute cardiovascular events occurred at the workplace, including 467 fatal cases. These are usually classified as ischemic heart disease, but this is not confirmed by microscopy and does not account for direct damage to the heart by coal-rock dust.

Objective. To provide microscopic evidence for defining “dust cardiomyopathy” as a distinct occupational heart disease.

Materials and methods. Heart tissue from 80 miners (work experience from 1 to 30 years) and 30 age‑matched healthy controls was examined using histology, histochemistry, and immunohistochemistry (markers CD34, CD31, α-SMA, TGF-β1, Bcl-2) with morphometric measurements.

Results. With increasing work experience, microvessel walls thickened by 1.5–2.5 times, and endothelial cell area increased by 2–4 times. As early as 1–5 years of exposure, lipofuscin pigment appeared in cardiomyocytes (area 143.7±33.6 µm²), peaking at 12–20 years (159.6±33.4 µm²) — significantly higher than in controls (p<0.001). Cardiomyocyte diameter increased up to 20.02±4.66 µm, heart weight to 530–580 g. For the first time, there was demonstrated a sign of endothelial‑to‑mesenchymal transition as the appearance of CD31 and CD34 proteins in vessel walls.

Limitations. Autopsy remains the gold standard for determining the cause of death. Experimental animal studies also end with autopsy, which does not question their validity. The study was conducted only on material from Kuzbass, using samples from those who died in industrial catastrophes, which requires careful interpretation.

Conclusion. The obtained morphological data provide a scientific basis for distinguishing dust cardiomyopathy as an independent occupational heart disease. Its hallmarks are damage to the inner lining of vessels, perivascular fibrosis, and lipofuscin accumulation. Further clinical studies are needed for final confirmation.

Compliance with ethical standards. The protocol was approved by the local ethics committee (Protocol No. 4, 21.11.2024).

Contribution:
Bondarev O.I. — concept, design, writing, editing;
Filimonov E.S. — material collection, data processing, literature review.
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: April 24, 2026 / Revised: May 17, 2026 / Accepted: July 1, 2026 / Published: August 14, 2026

Introduction. Vibration exposure to the body altering both neurohumoral regulation and functional parameters of the nervous system, leads to the development of tissue hypoxia and damage to cells of various organs. Studies of the effect of this physical factor on other organs have been published, but there are few studies of their biochemical status and morphological state, especially at the early stages of exposure.

The aim of the study was to study the features of changes in the morpho-functional state of the hepatobiliary system in rats in the dynamics of intermittent vibration exposure.

Materials and methods. The experiments were performed on male Wistar rats (n=59) weighing 160-240 g. An experimental group of rats was exposed to vibration at a fundamental frequency of 16 Hz, with a vibration acceleration of 120 dB. Vibration exposure was carried out in an intermittent mode. The morpho-functional state of the hepatobiliary system in rats was studied using a complex of biochemical and histological research methods. Blood sampling was performed in rats from the tail vein after 3, 6 and 9 weeks of the experiment. The biochemical parameters of blood serum, including aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, lactate dehydrogenase, creatine phosphokinase, cholinesterase, and gamma-glutamyl transferase, were detected by standard methods using Vector-Best diagnostic kits. Structural changes due to prolonged vibration exposure were assessed according to the results of morphological investigation of rat liver tissue. The results were processed using the Statistica software 10.0.

Results. At different examination periods, there were discordant reliable changes in the enzyme activity in the blood serum: increased AST activity at week 6 was aligned with the control by the end of the experiment; ALT activity was reliably raised at week 3 of the experiment, decreased to normal values at week 6 and increased again by week 9. There was a reliable decrease in the activity of alkaline phosphatase by the end of the 9^th week of exposure, a decrease in the activity of lactate dehydrogenase and creatine phosphokinase by week 3, a sharp increase by week 6 with a gradual decrease by the end of the experiment. Significant changes in activity by week 6 were detected in cholinesterase and gamma-glutamyl transferase. A comparison of the results of histological changes at the 3^rd, 6^th and 9^th weeks of exposure to vibration on the liver shows progressive morphological and structural changes in tissues, indicating to increasing damage, microcirculation disorders, inflammation and cellular dystrophy. While the changes only begin to appear at week 3, at weeks 6 and 9 they become more pronounced and reach a level associated with chronic tissue damage, which can lead to significant and, most likely, irreversible structural consequences in the future.

Limitations. In vivo experiments limit their number by directive documents on the protection of experimental animals, aimed at shortening research protocols and minimizing the number of test animals without compromising the reliability of the results.

Conclusion. The obtained results allow distinguishing three stages in the dynamics of intermittent vibration exposure to the hepatobiliary system. These stages include the first, during weeks 1–3 of the experiment, triggers adaptive mechanisms in the liver, resulting in increased cellular functional activity; the second stage of decompensation, a transitional period from the body’s physiological response to pathological disorders (week 6 of the experiment); and the third stage, exhaustion (week 9). Vibration exposure leads to an early breakdown of the liver’s compensatory mechanisms and the development of degenerative changes in the parenchyma, with the formation of foci of inflammation.

Compliance with ethical standards. The study was approved by the local Ethics Committee of the Federal State Budgetary Scientific Institution “Research Institute for Complex Problems of Hygiene and Occupational Diseases” (Minutes of meeting No. 4, § 2, dated November 18, 2021). Animal care, feeding, and withdrawal from the experiment were carried out in accordance with the requirements of the European Convention for the Protection of Vertebrate Animals used for Experimental and other Scientific Purposes (ETS No. 123, Strasbourg, March 18, 1986).

Contribution:
Gorokhova L.G. – concept and design of the study, conducting the experiment, material collection and data processing, writing the text;
Gostyaeva E.P. – material collection and data processing;
Zhukova A.G. – writing the text, editing, material collection and data processing.
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: April 24, 2026 / Revised: June 17, 2026 / Accepted: July 1, 2026 / Published: August 14, 2026

Introduction. The combination of the toxic effects of fluoride compounds with known risk factors for cardiovascular diseases can lead to the early development of diastolic ventricular dysfunction, thereby increasing the risk of complications.

Materials and methods. One hundred eighteen workers in the main occupations of the aluminum industry and 62 patients not exposed to fluoride compounds, aged between 40 and 55 years, were examined. All respondents underwent biochemical blood tests and echocardiography using standard methods.

Results. In aluminum production workers, regardless of the presence of concomitant chronic occupational intoxication with fluoride compounds, signs of left ventricular diastolic dysfunction were detected more often (67.8% of the cases) than in the control (29.0%, p<0.0001). Diastolic dysfunction of the left ventricle was more often diagnosed in persons with certain signs of fluoride exposure, suffering from arterial hypertension; diastolic dysfunction of the right ventricle was more common in patients with chronic occupational intoxication with fluoride compounds. In the control group, the prevalence of diastolic ventricular dysfunction did not depend on the presence of arterial hypertension and was significantly lower than in the aluminum workers. A relationship was found between dyslipidemia, atherosclerosis, and left ventricular diastolic parameters. No reliable association was revealed between pulmonary pathology and the development of right ventricular dysfunction. A reliable relationship was found between left ventricular dysfunction parameters and arterial blood pressure levels, as well as work experience under the conditions of exposure to fluoride compounds with ventricular dysfunction parameters.

Limitations. This study was limited to a sample size of workers of the main occupations in the aluminum industry who were examined at the Clinic of the Research Institute for Complex Problems of Hygiene and Occupational Diseases.

Conclusion. Diastolic ventricular dysfunction was detected in more than half of the aluminum industry workers, regardless of the presence of chronic occupational intoxication with fluoride compounds, which, in addition to the influence of arterial hypertension, increase in the level of low-density cholesterol, atherogenicity coefficient, and atherosclerosis, was also affected by the work duration in the conditions of exposure to fluoride compounds.

Compliance with ethical standards. In accordance with the Declaration of Helsinki of the World Medical Association (ed. 2013). the protocol of which met the requirements of the Bioethics Committee of the Research Institute for Complex Problems of Hygiene and Occupational Diseases (Protocol of the Meeting No. 4, § 2 dated November 18, 2021). All participants gave informed voluntary written consent to participate in the study.

Contribution:
Korotenko O.Yu. – concept and design of the study, collection of material, writing the text, editing;
Krasilnikova P.L. – collection 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 26, 2026 / Revised: June 21, 2026/ Accepted: July 1, 2026 / Published: August 14, 2026

Introduction. Prevention of violations related to nutrition being not only a medical and biological, but also a socio-hygienic problem, should be aimed primarily at eliminating the causes leading to these violations. Research shows that nutritional challenges for children remain.

The aim of the study Comparative analysis of calculated data on the food set, chemical composition and caloric content of the introduced diets for children, obtained by various methods.

Materials and methods. The study was carried out at a preschool educational institution during the pilot testing of a new diet (forty children in total). The object of the study was 4–6 years preschoolers living in mono-industry towns in the South of Kuzbass. The actual nutrition during the introduction of the new menu was studied by two methods: using the menu layout method (20 rations were calculated) and the weight-based method (9,600 servings).

Results. The actual consumption of the main macronutrients by children with food was 63–76% of the calculated data according to the menu layouts for proteins, 71–75% for fats and 79–85% for carbohydrates. The study found that during the menu testing period, the actual consumption of dishes and cooked products by children began to increase only on the third week of introducing the new ration; the children gradually got used to the menu. The consumption of milk and fermented milk products by children increased from 63% (of those stated in the menu layout) to 93%; cottage cheese from 71% to 97%; fish dishes from 50% to 77%; potatoes – from 67% to 85%; vegetables from 63% to 85% of the calculated data according to the menu.

Limitations. The study was limited to a sample size of preschool children who received food during the testing period of the new menu.

Conclusion. During the testing of new food rations at a preschool institution, it is entirely justified and appropriate to use the weight-based method for an objective assessment and study of the actual nutritional status of organized population groups.

Compliance with ethical standards. The study was approved by the Bioethics Committee of the Research Institute for Complex Problems of Hygiene and Occupational Diseases (Protocol of the Meeting No. 4 § 1 dated November 18, 2021), conducted in accordance with the commonly accepted scientific principles of the Helsinki Declaration of the World Medical Association (2013 edition). All participants and their legal representatives gave informed voluntary written consent to participate in the study.

Contribution:
Tapeshkina N.V. – the concept and design of the study, writing the text, editing;
Korsakova T.G. – collection of material;
Semenova E.A.– collection of material;
Povarnitsina N.V. – collection of material;
Logunova T.D. – data processing.
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: February 5, 2026 / Revised: July 2, 2026 / Accepted: July 6, 2026 / Published: August 14, 2026

Introduction. Lead nanoparticles are highly toxic and cause severe cell damage. When deposited on the olfactory epithelium in the respiratory tract, lead nanoparticles are captured by olfactory receptors and pass through the synapse into the olfactory bulbs. This can lead to the accumulation of reactive oxygen species and lipid peroxidation in mitochondrial membranes, thereby causing changes in their morphology and functioning, and subsequently inducing cell apoptosis.

The aim of the study. To investigate the effect of lead oxide nanoparticles on the mitochondrial profile of the rat olfactory bulbs following chronic inhalation exposure.

Materials and Methods. Adult female albino Wistar rats were divided into four groups of ten animals each. The experimental animals were chronically exposed to PbO NPs at a concentration of 0.215 mg/m³ for four hours a day, five days a week during four and eight months in a nose-only inhalation toxicity test chamber. After exposure cessation, olfactory bulb samples were collected for electron microscopy. The mitochondrial profile of rat brain neurons was assessed by the degree of damage to the inner membrane.

Results. We observed changes in neuronal mitochondria characteristic of physiological aging. Four-month inhalation exposure to PbO nanoparticles did not lead to significant changes in the mitochondrial matrix while a statistical increase in the mitochondrial health index was observed after 8 months.

Limitations. This study does not include quantitative measurements of the mitochondrial population of neurons.

Conclusions. Chronic 8-month exposure to lead nanoparticles significantly alters the ratio of normal to swollen forms of mitochondria, which may indicate to compensatory mechanisms. The observed changes may be attributed to accumulation of PbO NPs and a shift in their distribution in the olfactory structures, thus highlighting the importance of considering the time factor when assessing the neurotoxicity of lead nanoparticles.

Compliance with ethical standards. Ethics approval was provided by the Local Ethics Committee of the Yekaterinburg Medical Research Center for Prophylaxis and Health Protection in Industrial Workers (protocol No. 4 of July 12, 2022).

Contribution:
Shelomentsev I.G. – study conception and design, scientific editing;
Gorshkolepova A.V. – data collection and processing, draft manuscript preparation;
Muravtseva A.A. – data collection and processing, draft manuscript preparation;
Sutunkova M.P. – study conception and design;
Minigalieva I.A. – study conception and design.
All authors are responsible for the integrity of all parts of the manuscript and approval of its final version.

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

Funding. The study had no sponsorship.

Received: April 13, 2026 / Accepted: July 1, 2026 / Published: August 14, 2026

Introduction. Special relevance should be assigned to investigating a phenomenon of programmed cell death in working age population in the Far North exposed to airborne metals and sub-Arctic climate, with gene polymorphism taken into account.

Materials and methods. We examined adult participants (aged 21–59 years) who lived on territories with subarctic and continental type of climate with different levels of exposure to airborne nickel (n=525). Nickel levels were identified in blood using inductively coupled plasma mass spectrometry; cell death indicators AnnexinV-FITC⁺7AAD^– and AnnexinV-FITC⁺7AAD⁺ – were established with flow cytometry; vascular endothelial growth factor VEGF, immune enzyme assay; IgE to nickel, allergosorbent tests; VEGFA (rs2010963) gene polymorphism, real-time PCR.

Results. The immune profile in adults living in the Far North under low-dose exposure to airborne nickel (1.36 ∙ 10^-³ mg/(kg ∙ day); 0.12 average daily MPC) and with resulting nickel in blood (0.0123±0.0015 µg/cm³) was characterized with excess levels of AnnexinV-FITC⁺7AAD⁺ (R²=0.404–0.503; p=0.029–0.042) and IgE to nickel (R²=0.613; p=0.001). However, exposure to airborne nickel in sub-Arctic climate leads to relative risk RR=1.19 (1.03–1.36); p=0.005) for apoptosis inhibition per the level of AnnexinV-FITC⁺7AAD^– (R²=0.723–0.786; p=0.001–0.016). This risk is associated with the minor C-allele and CC-genotype of the VEGFA (rs2010963) (OR=1.91 (1.03–3.55)–2.93 (1.31–6.57).

Limitations. The reference group samples are limited; the results should be verified in future research

Conclusion. Exposure to airborne nickel in the average daily dose of 1.36 ∙ 10^–³ mg/(kg ∙ day), combined with the minor C-allele and CC-genotype of the VEGFA (rs2010963) induces changes in indices of cell death and the immune profile in adults in the Far North (declining AnnexinV-FITC⁺7AAD^– levels, growing levels of VEGF and IgE to nickel). These genetic and immunological indices can be recommended as key ones in pre-nosologic diagnostics and disease prevention in the far North population.

Compliance with ethical standards. The study was accomplished in conformity with ethical standards stipulated by the Declaration of Helsinki and approved by the local ethics committee of the Federal Scientific Center for Medical and Preventive Health Risk Management Technologies (Meeting Report No. 4 dated April 20, 2025). All participants gave informed voluntary written consent to participate in the study.

Contributions:
Zaitseva N.V. – study concept and design;
Nikonoshina N.А. – data collection and analysis, writing the text;
Dolgikh О.V. – study concept and design, editing the text;
Alikina I.N., Kazakova О.А. – immunogenetic studies;
Chigvintsev V.М. – mathematical modeling.
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 18, 2026 / Accepted: July 1, 2026 / Published: August 14, 2026

Introduction. The problem of air pollution in mono-industry towns, which are based on town-forming enterprises, is currently becoming particularly relevant.

The study aim was to determine the impact of atmospheric pollutants on the health of the population of two mono-industry towns in Khakassia based on the assessment of inhalation risk.

Materials and methods. The study was conducted in Chernogorsk and Sayanogorsk. The state of the atmospheric air is characterized, and the health risks to the population are calculated according to modern methods.

Results. In both mono-industry towns, excess of average annual concentrations of suspended solids, formaldehyde, and benzo(a)pyrene were observed. For acute inhalation exposure to pollutants, all hazard quotients in both towns corresponded to minimal or permissible (acceptable) risk levels, with hazard indices for critical organs and body systems at minimal levels. For chronic inhalation exposure, hazard quotients corresponded to warning levels in both towns over certain years. In 2022 and 2024, a high risk level from benzo(a)pyrene exposure was detected in Chernogorsk. Chronic respiratory risk corresponded to warning levels in both town, while childhood development risk corresponded to high levels in 2022 and warning levels in 2023–2024 in Chernogorsk. The total individual carcinogenic risk to the health of the population of both mono-industry towns was at a permissible (acceptable) level and was determined mainly by the contribution of formaldehyde (about 90%).

Limitations of the study were due to the use of official data on pollutant concentrations for risk calculations.

Conclusions. The results of the assessment of health risks to the population of single-industry towns in Khakassia from exposure to atmospheric pollutants obtained in this study should be used to optimize administrative and management decisions to improve the environmental situation. These results can also serve as objective criteria for the effectiveness of air protection measures implemented in Chernogorsk as part of the federal “Clean Air” project.

Compliance with ethical standards. This study did not require the conclusion of the Ethics Committee.

Contribution:
Kislitsyna V.V. – literature review, writing the text, editing;
Surzhikov D.V. – concept and design of the study, material collecting, writing the text;
Likontseva Yu.S. – data processing;
Golikov R.A. – data collecting and processing.
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: April 24, 2026 / Revised: May 7, 2026 /Accepted: July 1, 2026 / Published: August 14, 2026