Introduction. The interrelationships of vibration sickness (VS) and prognostically unfavorable acute cardiovascular events have not been studied sufficiently.

The study aims to determine the frequency and phenotype of adverse cardiovascular events in patients with vibration disease in comparison with people working in vibration conditions, without occupational diseases and in dynamics over 10 years.

Materials and methods. Study design: a retrospective, observational, single-center study. Vibration induced disease patients (n=1505) and workers exposed to vibration above occupational exposure limits without occupational diseases (n=1505) were included. The authors have obtained the data from the registry of the Center for Occupational Pathology and the medical information system. The endpoints were cases of myocardial infarction and unstable angina. Using the pseudorandomization method, the scientists compared the groups by gender, age, and type of production vibration. They determined the relative risk (RR) and 95% confidence interval (CI) of the event under study. To assess the 10-year dynamics of adverse cardiovascular events in the main group, the experts calculated moving averages of morbidity with an interval of two years. The significance level is p<0.05.

Results. Patients with vibration sickness had a higher incidence of all endpoints, relative risk (95% CI) 2.18 (1.79–2.65), acute myocardial infarction, RR 3.00 (2.13–4.22), with ST segment elevation, RR 4.73 (2.72–8.22) and without ST segment elevation, RR 2.04 (1.29–3.21), unstable angina, RR 1.78 (1.38–2.29). In the subgroups of myocardial infarction in patients with vibration disease, scientists noted an increase in the proportion of multivessel damage, RR 1.63 (1.09–2.43), as well as myocardial infarction without coronary artery obstruction (MICAO), RR 2.67 (1.002–7.10), MICAO and unstable angina in combination with signs of ischemia according to the results of stress tests or myocardial scintigraphy.

The authors observed the maximum increase in the relative risk and the number of associated acute forms of coronary heart disease in patients with vibration syndrome from exposure to local or combined vibration. The relative risk increased with the second degree of severity of the disease. During the 10-year follow-up period, the incidence of acute forms of coronary heart disease in the VS group increased: 1.6 times regardless of the nosological form, 1.9 times — acute myocardial infarction with ST segment elevation, 1.6 times — without ST segment elevation, and 1.5 times — unstable angina.

Conclusion. Vibration sickness is associated with an increased frequency of adverse cardiovascular events and is a promising risk factor.

Ethics. The study was conducted in compliance with the ethical principles set out in the Helsinki Declaration of the World Medical Association and in accordance with the Ethical standards and regulations stipulated in the Bulletin of the Higher Attestation Commission of the Ministry of Education, Russian Federation, No. 3 of 2002. The study was approved by the Ethics Committee of the Federal State Budgetary Educational Institution of Higher Medical Education of the Ministry of Health, Russian Federation, Protocol No. 161 dated 10/14/2024.

Contributions:
Shpagina L.A. — research concept and design, data collection and analysis, text writing;
Sergeev V.A. — research concept and design, data collection and analysis, text writing;
Kondyurina E.G. — data collection and analysis, text writing;
Zelenskaya V.V. — data collection and analysis, writing text;
Kotova O.S. — data collection and analysis, text writing;
Karmanovskaya S.A. — data collection and analysis, writing text;
Kuznetsova G.V. — data collection and analysis, text writing;
Kamneva N.V. — data collection and analysis, writing text.

Funding. The study had no funding.

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

Received: 21.07.2025 / Accepted: 25.07.2025 / Published: 05.09.2025

Introduction. Working in a chemical production environment is associated with a high risk of developing cardiovascular diseases (CVD) in workers.

The study aims to consider the characteristics of the immune and genetic status of workers with cardiovascular pathology engaged in the production of mineral fertilizers.

Materials and methods. The observation group included 74 people (with a history of CVD). The comparison group included 85 people (conditionally healthy, with no history of CVD). The work used immunological methods: allergosorbent test with an enzyme label, membrane immunofluorescence on a flow cytometer, ELISA. To statistically process the results of the study, the authors used the following criteria: Student's t-test, Mann–Whitney U-test, relative risk index (RR), odds ratio (OR) and 95% confidence interval (CI). The significance of the differences was considered significant at p<0.05.

Results. The observation group had elevated levels of IgG specific to N-nitrosodimethylamine (RR=1.10; 95% CI=0.93–1.29), VEGF (RR=1.72; 95% CI=0.64–4.61), CD304⁺ (NRP1) (RR=1.76; 95% CI=1.04–2.97) and Notch 1 receptor (RR=1.89; 95% CI=1.05–3.39). Comparative assessment of frequency of alleles and genotypes of the endothelial NO-synthase gene eNOS Glu298Asp (rs1799983) revealed authentically 10% higher frequency of the G allele (OR=2.53 (CI=1.23–5.22), RR=1.28 (CI=1.06–1.55), р≤0.05) and 1.67 times higher frequency of the GG genotype (OR=3.72 (CI=1.49–9.29), р≤0.05) in the observation group.

Limitations. Limitations of the study are associated with a limited sample used as the observation group.

Conclusion. Established elevated expression of cell differentiation clusters of neuropilin-1 CD 304⁺ (RR=1.76; 95% CI=1.04–2.97) and transmembrane receptor protein Notch 1 (RR=1.89; 95% CI=1.05–3.93) against higher frequency of the G allele and GG genotype of the eNOS Glu298Asp gene increases likelihood of changes in endothelium, impaired vascular wall permeability and development of cardiovascular pathology in conditions of biocontamination with nitrosamines among workers working in the production of mineral fertilizers.

Ethics. The work was carried out in accordance with the principles of the Helsinki Declaration. The protocol and design of the study were approved by the local committee of the Federal Research Foundation "Federal Scientific Center for Medical and Preventive Technologies for Public Health Risk Management" dated 03/13/2024, Protocol No. 2.

Contributions:
Zaitseva N.V. — concept and design of the study;
Chelakova Yu.A. — data collection and processing, text writing, editing;
Dolgikh O.V. — concept and design of research, editing.

Funding. The study had no funding.

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

Received: 18.04.2025 / Accepted: 15.07.2025 / Published: 05.09.2025

Introduction. The worsening situation with increasing mortality from cardiovascular diseases among the able-bodied population requires the development of new concepts for diagnosis, treatment, and, above all, algorithms for preventive measures. Workers engaged in underground coal mining are exposed to a complex of harmful production factors that provoke the development and progression of metabolic disorders, which allows them to be classified as a group of increased cardiac risk. The search for markers of early cardiometabolic disorders is necessary for a comprehensive approach to assessing the cardiovascular risk in these workers. The inclusion of new informative indicators in the screening program for the most vulnerable population will increase the effectiveness of preventive measures and reduce the risk of developing cardiovascular pathology.

The study aims to analyze the relationship between the level of total testosterone and indicators of cardiometabolic disorders in workers engaged in underground coal mining.

Materials and methods. The scientists have conducted an in-depth survey of 76 workers engaged in underground coal mining, aged 37 to 49 years. The authors have evaluated the parameters of lipid and carbohydrate metabolism, markers of inflammation, and the level of total testosterone. Comparison groups were formed depending on the level of testosterone.

Results. Workers engaged in underground coal mining with testosterone levels within the lower quartile range showed significant (p<0.05) changes in the state of carbohydrate and lipid metabolism, and higher levels of highly sensitive C-reactive protein compared with those with testosterone levels within the upper quartile range. Using ROC analysis, a threshold level of total testosterone was established, below which an increased risk of cardiometabolic disorders at the age of 37–49 years is predicted — 11.22 nmol/l.

Limitations. The study is limited to a sample of surveyed workers engaged in underground coal mining in the age range of 37–49 years.

Conclusion. The obtained results indicate a relationship between a decrease in total testosterone levels and the development of disorders of carbohydrate and lipid metabolism, activation of inflammatory processes, which indicates the importance of including testosterone in a set of indicators to assess the risk of cardiometabolic disorders in workers engaged in underground coal mining.

Ethics. The study was conducted in compliance with ethical standards for conducting medical research involving humans in accordance with the requirements of the Helsinki Declaration of the World Medical Association. The study was approved by the conclusion of the local Ethics Committee of the Izmerov Research Institute of Occupational Health (minutes of the meeting No. 5 dated 08/02/2023).

Contributions:
Kuzmina L.P. — research design, text editing;
Kislyakova A.A. — conducting research, statistical data processing, writing and editing text;
Kolyaskina M.M. — conducting research, statistical data processing, writing and editing text;
Khotuleva A.G. — conducting research, statistical data processing, writing and editing text;
Anokhin N.N.— writing and editing text.

Funding. The study had no funding.

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

Received: 04.07.2025 / Accepted: 21.07.2025 / Published: 05.09.2025

Introduction. Currently, the hygienic characteristics of the working conditions of employees of enterprises with harmful working conditions are based mainly on the standard method of workplace air sampling without taking into account individual physiological parameters, different degrees of physical exertion of employees at individual levels of the technological process during the work shift.

The study aims to make a comparative assessment of the air pollution indicators of the working area of workers of the nickel electrolysis workshop using standard and individual sampling methods.

Materials and methods. The scientists have conducted research at mining and metallurgical enterprises of the Murmansk region located in the European part of the Arctic zone of the Russian Federation. These enterprises are part of the mining complex of the region and are engaged in the extraction and processing of copper-nickel sulfide ores in order to obtain finished products — electrolytic nickel. The authors conducted air sampling in industrial premises using standard methods using individual samplers during a work shift.The nickel content in the aerosol was determined using a polarographic method based on the reduction of nickel dimethylglyoximate complexes on a mercury droplet electrode in the presence of chloride‑ammonia buffer and sodium sulfite. The method of inductively coupled plasma atomic emission spectrometry was used to analyze the metal content.

Results. A comparative analysis of the results showed that the use of individual sampling devices makes it possible to objectively assess the level of exposure to toxic water-soluble nickel compounds. Experts have established that the method of individual sampling in terms of the frequency of exceeding the maximum permissible concentration in the air of the working area by 30.5%, compared with the standard procedure, gives a more accurate picture of the degree of risk of harm to the health of workers with harmful chemical factors. The use of individual sampling techniques can increase the objectivity of the results of control and supervisory measures in the field of occupational health and expert decisions in establishing a link between diseases and the profession of workers in harmful chemical industries.

Limitations. Conducting studies on the hygienic assessment of chemical air pollution in the working area in the production facilities of the nickel electrolysis workshop was difficult due to the difficulties of passing the admission procedure to the territory of the metallurgical enterprise.

Conclusion. Hygienic characteristics of chemical air pollution in the work area using the method of individual sampling significantly increases the objectivity of quantifying the risk to the health of chemical industry workers and reduces the time required for laboratory tests.

Ethics. The study does not require the provision of an opinion from the biomedical Ethics Committee or other documents.

Contributions:
Shilov V.V. — concept, editing and approval of the final version of the article;
Nikanov A.N. — collection and statistical processing of the material, editing of the article;
Barinov V.A. — research concept and design, editing;
Petrukhin N.N. — statistical processing of the material and editing of the article;
Andreenko O.N. — research design and article editing.
All co-authors — responsibility for the integrity of all parts of the article.

Funding. The study had no funding.

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

Received: 11.07.2025 / Accepted: 23.07.2025 / Published: 05.09.2025

Introduction. The multidimensional (medical, social, economic, legal, moral and ethical) problem of professional hearing disability remains one of the most urgent in occupational health.

This is due to the fact that indicators of occupational hearing loss occupy the first place in the structure of occupational morbidity, without a downward trend, as well as an increase in the number of workers with professional hearing disability and a wide prevalence of risk factors for hearing impairment — noise, infra- and ultrasound, vibration, heating microclimate, chemical ototoxic factors, certain types of work, for which the condition of the hearing organ is important.

The study aims to optimize the risk management of the professional unfitness of hearing workers to work under the influence of physical, chemical ototoxic factors and certain types of work.

Materials and methods. The authors have carried out an expert and analytical study. At the first stage, experts conducted a comparative analysis of regulatory legal acts regulating the procedure for conducting mandatory preliminary and periodic medical examinations (PME) for the period 1957–2021.

At the second stage, they analyzed and statistically processed data from the "MEDIALOG" medical information system, including the results of PME performed at the Institute's clinic in 2019–2023 (a total of 104,482 people aged 20 to 80 years, including 5,177 with medical contraindications, 1300 of them for hearing). According to the GOST R ISO 1999-2017 model, the attributive risk of hearing loss for employees of various classes of working conditions, age, and length of service groups is calculated, and a single-digit index of professional unfitness is justified.

Results. The authors proposed measures to optimize the PME of workers in terms of physical, chemical, ototoxic factors and certain types of work (adjusting the scope of research and the list of medical contraindications). In the structure of medical contraindications to work with harmful and(or) dangerous industrial factors and types of work identified in 5,177 employees (hereinafter referred to as medical contraindications), diseases of the eye and its accessory apparatus (ICD-10, class VII) occupy the first place — 26.39%, the second — diseases of the ear and mastoid process (ICD-10, class VIII) — 25.11%, the third — circulatory diseases (ICD-10, class IX) — 12.63%. The frequency of identified medical contraindications per 10,000 examined patients amounted to 495.49 cases, professional unfitness — 190.75 cases. Of the 1,300 workers (mostly men) with medical contraindications to hearing, 44.9% were more often registered in the age groups 50-59 years old and 27.10% in the age groups 60-69 years old, 1,028 people had a sensorineural form of hearing loss (79.08%). 842 people (64.7%) and 455 people (35.0%) were found eligible, with an average age of 53.7±0.3 years and 56.1±0.5 years, respectively (p<0.05). The frequency of identified (per 10,000 examined) hearing contraindications amounted to 124.42 cases, occupational unfitness — 43.55 cases, preliminary diagnoses of occupational diseases — bilateral sensorineural hearing loss — 27.09 cases. The largest share of professionally unsuitable workers (64.6%) is accounted for by workers in professions associated with increased noise levels, 29.4% by those who work at height, and 6.0% by those who work in contact with lead and its inorganic compounds. According to the attributive risk data (a model according to GOST R ISO 1999-2017), an overestimation of the criterion values of the hearing thresholds adopted in the classification of clinical recommendations (2024) was confirmed, and a single-digit indicator of professional hearing disability was justified.

Conclusion. The improvement of regulations governing the conduct of medical examinations will improve the effectiveness of medical examinations and the examination of the professional suitability of employees. In order to implement risk-based prevention or risk management, it is necessary that the PME and the examination of professional aptitude be completed by organizing the rehabilitation of employees and developing individual preventive measures taking into account the attributive risk of hearing impairment.

Limitations. The study is limited by the number of employees who have undergone mandatory pre-employment and periodic medical examinations, types of economic activities and professions.

Ethics. This study did not require the conclusion of an Ethics Committee.

Contributions:
Prokopenko L.V. — research concept and design, data collection and interpretation, text writing;
Lagutina A.V. — data collection, processing and interpretation, text writing;
Kuryerov N.N. — data processing.

Funding. The study had funding.

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

Received: 00.00.2025 / Accepted: 31.07.2025 / Published: 05.09.2025

Introduction. Modern livestock enterprises ensure the country's food security. The implemented automation of technological processes can reduce the impact of traditional harmful factors. In this regard, it is the biological factor that is one of the main occupational risk factors. The widespread use of antibiotics and feed additives contributes to the emergence of multidrug‑resistant strains. Antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARG) are circulating among animals and the environment and can pose a danger to people in contact with animals.

The study aims to evaluate the content and resistance to antibacterial drugs (with the identification of resistance genes) of priority gram-positive microorganisms that cause opportunistic infections in the production environment of the livestock complex.

Materials and methods. The authors analyzed the content of gram-positive strains of microorganisms detected in the production environment of livestock complexes and studied the antibiotic sensitivity of isolated strains of Staphylococcus aureus and Enterococcus faecalis. The scientists conducted the diagnosis of methicillin resistance in 89 isolates of Staphylococcus aureus by PCR with hybridization-fluorescence detection.

Results. The content of microorganisms in the air of the working area ranges from 112,124 to 242,700 thousand microbial bodies/m³. Gram-positive flora dominates, with representatives of the genus Enterococcus predominating (in 60±5.3% of samples). The total content of bacteria of the genus Staphylococcus is up to 20±4.6% of samples.

In the structure of microorganisms, when examining flushes from surfaces in the work area, the predominance of strains of the genus Staphylococcus (in 90±3.8% of samples) and the genus Enterococcus (in 95.0±0.5% of samples) was established, the species Enterococcus faecalis was isolated in 85.0±2.7% of samples.

Gram-negative flora was identified in 40±1.6% of samples (Proteus vulgaris, Echerichia coli, Citrobacter freundii, Klebsiella spp. in the amount of 10⁶ CFU/tampon). The bulk of the isolated microorganisms consisted of 2-3-component cultures (90±1.6%). The strains demonstrate resistance to: tetracyclines (100%), macrolides (88.2%), fluoroquinolones (ciprofloxacin — 35.3%, norfloxacin — 41.2%), lincosamides (clindamycin — 88.3%); aminoglycosides (amikacin — 82%, gentamicin — 58.8%, tobramycin — 88.2%), penicillins (ampicillin — 57%) and glycopeptides (vancomycin — 46.6%).

All Staphylococcus aureus is characterized by simultaneous resistance to several antibiotics. In the studied sample, Staphylococcus aureus methicillin resistance (mecA) DNA was identified in 38.2% of the analyzed samples.

All isolates of the Enterococcus faecalis species demonstrate 100% resistance to imipenem and erythromycin, and sensitivity to ampicillin in 90.1% of cases. Up to 90% of the strains are resistant to gentamicin, levofloxacin and ceftriaxone. Half (50.0±5.50%) of Enterococcus faecalis isolates have multiple drug resistance (to three or more classes of antibacterial drugs).

Limitations. The limitation of this study is the simultaneous sampling in winter, before cleaning and disinfection of premises and equipment.

Conclusion. To assess the health risks of employees of livestock enterprises, a comprehensive sampling strategy using additional sampling methods, as well as the use of a combination of various nutrient media and molecular methods for isolating resistance genes of identified microorganisms, is of paramount importance. Reduction of microbial contamination of the air should be ensured by compliance with the regulated requirements for the sanitary and hygienic maintenance of animals. Comprehensive health improvement plans should include preventive and focal disinfection, disinfection and deratization. Due to the growing need for the rational use of available antimicrobial drugs, taking into account the spectrum of their activity and the profile of antibiotic resistance of the main pathogens, the results of the research can be used in the treatment of inflammatory diseases in employees of these enterprises.

Ethics. The conducted research did not require the conclusion of the Ethics Committee.

Contributions:
Masyagutova L.M. — review of publications on the topic, analysis of literary sources, generalization of data;
Gizatullina L.G. — sampling for bacteriological analysis, conducting research, analyzing the results;
Bakirov A.B. — data synthesis, editing;
Zaidullin I.I. — material processing, editing.
All co-authors — responsibility for approving the final version of the article and ensuring the integrity of all parts of the article.

Funding. The study had no funding.

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

Received: 17.07.2025 / Accepted: 24.07.2025 / Published: 05.09.2025

Introduction. Pollution of the environment with tetracycline is caused by both emissions from pharmaceutical production and the introduction of antibiotic residues with manure as fertilizer, which requires the development of methods for cleaning, monitoring the content and studying the stability of the substance in the soil to reduce environmental risks.

The study aims to investigate the stability of tetracycline and the determination of its transformation products in the soil environment.

Materials and methods. Preparation of standard tetracycline solutions and their loading into the soil. Extraction of tetracycline from soil with EDTA-McIlwain buffer followed by purification by solid phase extraction. Analysis of extracts by chromatography with tandem mass spectrometry for quantitative and qualitative determination of the starting material and its transformation products. Comparative analysis of mass spectra of soil extracts to identify new decomposition products and assess the rate of degradation.

Results. In soil, tetracycline undergoes gradual transformation with a half-life of 5–7 days for sod-podzolic soil and 8–12 days for chernozem; at the same time, decarboxamidation, deamination and dehydroxylation products accumulate, and researchers have also discovered previously undescribed compounds (m/z 679 and 701) with a suspected dimeric structure. Regardless of the type of soil, the composition of the transformation products was the same, which indicates similar mechanisms of antibiotic decomposition in different soil conditions.

Limitations. The authors conducted the study in laboratory conditions using artificially contaminated soil samples, which may not fully reflect the complexity and diversity of real soil ecosystems and natural tetracycline transformation processes. They studied only two types of soil (sod-podzolic and chernozem), while in nature there is a much greater variety of soils with different physico-chemical properties that can significantly affect the rate and nature of the breakdown of the antibiotic. Experts identified the decay products only from mass spectrometric data without confirming their structure using additional methods (for example, NMR-spectroscopy), which leaves the possibility of erroneous interpretation of the composition of the products.

Conclusions. Tetracycline decomposes rapidly in the soil to form new transformation products, including previously undescribed ones, which can significantly affect environmental safety and requires further study of their properties and consequences for the environment.

Ethics. The study does not require the provision of an opinion from the biomedical Ethics Committee or other documents.

Contributions:
Antropova N.A. — collecting and processing material, performing experimental work, writing text, editing;
Streletskiy A.V. — concept and design of research, collection and processing of material, experimental work, statistical processing, text writing, editing;
Ushakova O.V. — research concept and design, editing;
Yudin S.M. — editing.

Funding. The study was conducted with financial support as part of a government assignment.

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

Received: 29.07.2025 / Accepted: 02.08.2025 / Published: 05.09.2025