Introduction. COVID-19 has had a particular impact on the health of medical workers who are in the most intense contact with infected people. This is confirmed by foreign studies. There have been no epidemiological studies on the mortality of medical workers from COVID-19 in Russia.

The study aims to conduct a comparative analysis of mortality from COVID-19 in professional groups of staff of a large medical network and the Russian population.

Materials and methods. Based on depersonalized information from the network of healthcare institutions of Russian Railways-Medicine JSC on the gender and age composition of staff and those who died during the three years of the pandemic and Rosstat data on the sex and age of the population and the number of deaths for 2020-2022 (form C-51), a cohort epidemiological study of mortality from COVID-19 of medical workers compared with the Russian population was performed.

The researchers formed two groups — male and female. Both groups included medical (doctors, middle and junior medical staff) and non-medical workers. During the period from 01.01.2020 to 31.12.2022, the number of person-years of follow-up was 25,099 in the male cohort and 134,208 in the female cohort. 40 men and 73 women died. The second stage of the study was an in-depth analysis of mortality in individual years of the pandemic based on age-standardized mortality rates for each of the occupational groups. Standardization was carried out using the direct method.

Results. In the male cohort, the risk of dying from COVID-19 was significantly higher than the population risk (SIR=1.86; 95% CI 1.05–3.31). The indicator was formed due to the high risk in the professional group of doctors (SIR=1.96; 95% CI 1.06-3.62). Female doctors had a SIR=1.37, but the differences were unreliable (95% CI 0.77–2.44). In the remaining professional groups of the female cohort, the death rate was significantly lower than the population level.

An analysis of standardized mortality rates in individual years of the pandemic showed that mortality from COVID-19 was particularly high in the first year. Male doctors had a 3.97-fold higher mortality rate than the population and 3.6-fold higher mortality rate for women. There was also a tendency to an increased mortality rate among men in the group of secondary medical personnel. In the remaining occupational groups of both sexes, mortality rates were significantly lower than in the population. In 2021 and 2022, the indicators for non-medical and medical workers were significantly lower than in the population, or no differences were found.

Limitations. Lack of data on the specific place of work of medical personnel (hospital, polyclinic, etc.).

Conclusion. It was found that in Russia's largest medical network during the COVID-19 pandemic, a high risk of death compared to the Russian population was registered among doctors of both sexes and male nursing staff in the first year of the pandemic (2020). This deserves further study and points to the need to adapt the healthcare system to possible new challenges.

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

Contributions:
Bukhtiyarov I.V. — research concept and design, editing, approval of article final version;
Tikhonova G.I. — research concept and design, writing and editing the text, responsibility for the integrity of all parts of the article;
Strizhakov L.A. — concept and design of research, editing;
Gorchakova T.Yu. — collecting material and data processing, writing text, editing;
Khvalyuk P.O. — collecting literature data, writing text;
Pershin S.E. — writing the text;
Kostenko N.A. — material collection and data processing;
Kovalevsky E.V. — concept and design of research, editing;
Tskhomariia I.M. — collecting literature data, writing text;
Ustarkhanova A.K. — data processing and visualization.

Funding. The study had no funding.

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

Received: 21.04.2025 / Accepted: 30.04.2025 / Published: 08.05.2025

Introduction. Preservation of labor potential of coal industry workers seems to be a priority direction in occupational medicine. The realization of this direction is possible due to the introduction of systemic medical and preventive technologies both in the industry as a whole and at individual workplaces of miners. A characteristic feature of professional activity of coal industry workers is not only being in harmful and hazardous working conditions but also increased requirements to the qualification of the workers, labor motivation, responsibility, emotional stability, working capacity. Under the influence of harmful factors caused by professional activity, a negative state of overexertion can develop — professional stress, which increases the risk of developing professional burnout and occupationally related diseases.

The aim of the study is to assess the level of professional burnout and occupational stress factors affecting the health and working life expectancy of workers engaged in underground coal mining.

Materials and methods. The authors conducted psychological testing to identify professional burnout (Maslach Burnout Inventory, n=252) and its degree according to the model of Golembiewski and Munzenrieder, labor stressors (Spielberger labor stress questionnaire, n=171), stress resistance and social adaptation (Holmes and Rahe stress scale, n=249). Nine professional groups of mine workers (n=252) took part in the study: mine fitters, mine workers, mine face workers, drilling rig operators, mining and demolition machine operators, mechanics, assistant site supervisors, sinkers and electricians. Each worker gave informed voluntary consent to participate in the study.

Results. The main contribution to the development of professional burnout is made by the factor of reduction of personal achievements: a high level of this factor was revealed in 129 mine workers — 51.2%. A high level of the depersonalization factor was noted in 48 workers out of 252 — 19.0%, while a correlation was noted between age and the level of the factor: r(250)=0.133, p=0.035. A high level of emotional exhaustion was noted only in 12 miners out of 252 — 4.8%, which determines a small number of workers with a high degree of burnout — 11.5%. Leading work stressors were identified for each professional group of workers. No relationship was found between the level of social stress, the number of stressful events per year and burnout factors (p>0.05).

Limitations. For a comprehensive assessment of the health of workers, it is important to conduct physiological and psychophysiological studies in the dynamics of the work shift, as well as a hygienic assessment of working conditions. However, conducting these studies is difficult due to the complexity of the procedure for admission to the mine, as well as the presence of spark-proof equipment. The study is also limited to conducting psychological testing on workers of only one mine, which requires further study of the issue to increase the representativeness of the data obtained.

Conclusion. Professional burnout of mine workers is caused by the cognitive-emotional factor of reducing personal achievements associated with work stressors. It is necessary to pay attention to situational and organizational characteristics, measures to reduce the impact of identified stressors. Identifying sources of stress will help improve working conditions and increase the efficiency and reliability of workers, extend their working longevity.

Ethics. The study was conducted in accordance with the Declaration of Helsinki and approved by the Local Ethical Committee of FSBSI IRIOH, protocol No. 5 of 02.08.2023.

Contributions:
Kuzmina L.P. — research concept and design, editing;
Tolmachev D.A. — research concept and design, data collection, writing, editing;
Golovkova N.P. — research concept and design, editing;
Eremeeva A.G. — conception and design of the study, data collection, writing, editing;
Kalinina S.A. — conception and design of the study, data collection, writing, editing;
Lyubimova M.S. — conception and design of the study, text writing, editing;
Tskhomaria I.M. — conception and design of the study, text writing, editing;
Varakuta I.S. — research concept and design, data collection, editing;
Chasovskikh E.V. — research concept and design, data collection, editing.

Funding. The study was conducted as part of research work No. FGFE-2023-0014

Conflict of interest. The authors declare that there is no conflict of interest.

Received: 12.02.2025 / Accepted: 18.03.2025 / Published: 08.05.2025

Introduction. At workplaces of high and extra-high voltage open switchgears there are high levels of power frequency electric (EF) and magnetic fields (MF), which can exceed the maximum permissible levels (MPL). In case of exceeding the MPL, ensuring electromagnetic safety is realized by using personal protective equipment (PPE). All EF PPE certificated in homogeneous EF test, but in real conditions at electrotechnical staff workplaces are the heterogeneous EF.

The study aims to hygienic assessment at workplaces of electric power facilities and shielding suit protective properties investigation in full-scale and laboratory conditions.

Materials and methods. Hygienic assessment of EF and MF was carried out at the ground workplaces of the electrical staff while performing works at 220, 330, 500 and 750 kV switchgears. Studies of suit protective properties were carried out according to domestic and international methods using three PPE with different sets.

Results. EF hygienic assessment showed exceeding of MPL at all investigated objects with the EF maximum level 29,91 kV/m. Shielding suit protective properties evaluation showed that all PPE had sufficient protective properties of Russian requirements for ground workplace (30 dB).

Limitations. The limitation in the number of studied electric power facilities is due to the difficulties of obtaining access to such facilities.

Conclusions. EF hygienic assessment showed exceeding MPL at all investigated objects. The EF maximum values were fixed at 750 kV switchgear (29,91 kV/m). Exceeding the MPL for the whole work time in 5 kV/m at all studied objects on average amounted to more than 60% of the territories of all objects.

The protective properties suit evaluation in full-scale and laboratory conditions showed adequate results (does not exceed 20%) and the possibility of assessing the protective properties effectiveness using a Russian Federation methodology as well as international.

Ethics. The study did not require an ethical committee opinion.

Contributions:
Perov S.Yu. — concept and design, collecting and processing data, writing text, editing;
Dremin A.I. — collecting and processing data, writing text.

Funding. The study had no funding.

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

Received: 14.03.2025 / Accepted: 03.04.2025 / Published: 08.05.2025

Introduction. Diseases of the musculoskeletal system from functional overexertion in response to prolonged intense workload at the workplace, have so far occupied one of the leading places in occupational pathology. However, a number of questions regarding the diagnosis of fatigue of the peripheral neuromuscular apparatus, the conditions for its transition to overwork and overstrain require further study. In connection with the development of the concept of viscoelastic properties of skeletal muscles, it became possible to objectively assess the state of the peripheral link of the neuromuscular apparatus at different levels of fatigue, which makes it possible to clarify the mechanisms of the development of diseases of the musculoskeletal system from functional overstrain.

The study aims to explore the dynamics of indicators of biomechanical and viscoelastic properties of skeletal muscles during the development of local muscle fatigue and to find out the possibility of using these indicators for an objective assessment of the state of fatigue of the musculoskeletal system.

Results. A myotonometric study revealed an increase in the biomechanical properties of the muscles of the forearm — tone and stiffness and a decrease in the viscoelastic properties of creep and relaxation time, more pronounced during overwork. Changes in elasticity are less significant, since its parameters depend on the anatomical and structural properties of the muscle.

A positive relationship was established between muscle strength measured by dynamometry and the tone and stiffness of wrist flexors obtained by myotonometry.

Limitations. Limitations relate to the small sample of subjects.

Conclusion. It was found that for the most objective assessment of muscle fatigue, a set of indicators was used, including the determination of muscle strength by the dynamometric method, tone, rigidity, creep and relaxation time according to myotonometry.

The identified changes in the properties of muscle tissue not only expand our ideas about the development of fatigue but also clarify the mechanisms of the formation of diseases of the musculoskeletal system from functional overstrain.

Ethics. This human subject study was conducted in compliance with the ethical principles presented in the latest version of the Declaration of Helsinki developed by the World Medical Association.

Contributions:
Suvorov V.G. — study concept and design, literature analysis, writing the final version of the article;
Shitova E.S. — material acquisition and data processing, writing a preliminary version of the text.

Funding. The study had no funding.

Conflict of interest. Authors declare no conflict of interest.

Received: 07.04.2025 / Accepted: 10.04.2025 / Published: 08.05.2025

Introduction. Prolonged exposure to the factors of nervous and stressful mental labor forms unfavorable stress conditions of physiological systems, increasing the risk of developing occupational diseases, including pathology of the cardiovascular system. Numerous studies devoted to the study of the functional state have not revealed a sufficiently unified approach to its assessment, which determines the relevance of this work.

The study aims to develop criteria and methods for assessing the functional state and factors of the labor process of workers in neuropsychiatric labor, taking into account people of different age groups to preserve health and labor potential.

Materials and methods. The researchers assessed the functional state according to pre-shift medical control data on professional groups of ground transport drivers and employees of locomotive crews of Russian Railways, which were selected and analyzed based on gender and age differences. According to the indicators of heart rate, blood pressure, scientists calculated the production parameters of hemodynamics (peripheral resistance, minute volume), indices of the cardiovascular system (Index of Functional Changes, Myznikov index, Kerdo vegetative index), which revealed a close correlation with age. The authors carried out statistical processing of the obtained data using IBM SPSS Statistics 26 software.

Results. Based on the database of pre-trip medical examinations, specialists have developed a model for the step-by-step geometric construction of nonlinear fluctuations of the cardiovascular system, which allows us to assess and predict the functional state of a person, the degree of disturbance of vegetative balance, and the risks of developing pathology in the cardiovascular system. Based on the parameters of the digital profiles of employees, taking into account gender and age characteristics, new algorithms for assessing the functional state for monitoring the working capacity of employees were introduced into the existing digital information system of the Institute's Medical Information System.

Conclusion. The researchers have developed a criterion apparatus and a set of methods for assessing the indicators of the functional state of the body (according to the indicators of the cardiovascular system) in conditions of neuro-emotional labor activity, taking into account the influence of factors of tension and severity of the labor process on the health of workers (risks of arterial hypertension) of various gender and age groups in modern conditions. Based on the results of comprehensive studies of workers in neuropsychiatric mental labor, the standards of work intensity were improved, and the authors proposed a new version of the indicator "Work with information load and creative content (% of shift time)".

Limitations. There are limitations due to the peculiarities of collecting (obtaining) physiological data during pre-trip medical examinations.

Ethics. The study was approved by the local Ethical Committee of Izmerov Research Institute of Occupational Health (protocol No. 1 of February 16, 2022).

Contributions:
Glukhov D.V. — concept and design of the study;
Yushkova O.I. — text writing, editing;
Kapustina A.V. — collecting and processing material, text writing;
Forverts A.Yu. — collection and processing of material, editing.

Funding. The study had no funding.

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

Received: 03.04.2025 /Accepted: 04.04.2025 / Published: 08.05.2025

Introduction. The COVID‑19 pandemic has become a global stressful factor for population health in most countries, including Russia. Although the elderly population was most affected, the pandemic had a significant impact on the health of the working-age population. In the course of this study, it was necessary to find out exactly how.

The study aims to consider the patterns of the COVID‑19 pandemic's impact on morbidity and mortality in Russia's working-age population.

Materials and methods. The authors analyzed data for the Russian Federation from the medical reporting form No. 12 and Rosstat data on mortality from tables C 51. We used reports for 3 years before the COVID 19 pandemic (2017–2019) and for 3 years after the pandemic (2020–2022). Data on the primary morbidity and mortality of the working-age population were selected in the reports. The age related incidence of COVID-19 according to form No. 16 VN and age related mortality from COVID-19 according to tables C-51 for 3 years of the pandemic were also analyzed for 10 age groups, separately for men and women. For the calculations, the researchers used Rosstat data on the population.

Results. During the pandemic, there was a marked increase in the incidence of respiratory diseases (by 19.7%–34.6%) in parallel with the increase in the incidence of COVID-19, which suggests an incomplete diagnosis of COVID-19 cases. At the beginning of the pandemic, in addition to COVID-19, there was a significant increase in mortality from respiratory diseases (by 21.4%–36.6%), circulatory system diseases (by 4.4%–10.0%) and digestive diseases (by 12.6%–20.8%), which may indicate the negative impact of coronavirus on a number of organs and body systems. When analyzing the age distribution of COVID-19 incidence, it was found that in all age groups, during all years of the pandemic, the incidence among women was much higher than among men (1.3–1.7 times), however, an analysis of age-related mortality rates from COVID-19 found higher values in men (1.2–1.7 times), this may indicate an insufficient detection rate of COVID-19 cases among men.

Conclusion. The pattern of changes in the morbidity and mortality rates of the working‑age population during the COVID-19 pandemic indicates the significant damage caused by the coronavirus to the health of this category of the population. Some data suggest incomplete diagnosis of COVID‑19 cases, especially in the male population.

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

Contributions:
Pershin S.E. — research concept and design, analysis data, text writing, editing;
Tikhonova G.I. — concept and design of research, editing;
Gorchakova T.Y. — analysis data, editing;
Khvalyuk P.O. — analysis data, editing.

Funding. The study had no sponsorship.

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

Received: 25.03.2025 / Accepted: 08.04.2025 / Published: 08.05.2025

Introduction. Currently, the problem of wildfires is acquiring a global scale, and in the conditions of climate change, their further increase is predicted. The constant increase in the scale of wildfires and long-term annual smoke pollution of vast territories dictate the need to study the mechanisms of combustion products toxicity, including the assessment of their neurotoxic effect.

The study aims to assess the effect of acute peat smoke intoxication on the indices of the functional state of the central nervous system of white rats.

Materials and methods. The studies were performed on 20 white outbred male rats exposed to peat smoke for 4 hours. A day after the end of the exposure, the animals were examined using the open field and Morris water maze tests. EEG indices were also assessed.

Results. Exposure to peat smoke for 4 hours was accompanied by a pronounced inhibition of the motor and exploratory activity of white rats, as evidenced by a decrease in the distance traveled and a decrease in the area of the studied arena compared to the control group. The results of electroencephalography revealed a statistically significant decrease in the average EEG amplitude in the left and right hemispheres by 23% and 20%, and a decrease in the average signal power in the θ-frequency range by 10–11%, α-rhythm and β1-rhythm — by 22-27%.

Conclusion. Our results indicate that a single 4-hour inhalation exposure to smoke from thermal destruction of peat containing the main components: CO — 24 mg/m³ and PM_2.5 — 0.32 mg/m³ causes changes in both the rats' behavior and EEG parameters. In the formation of neurotoxicity in rats when inhaling smoke from thermal destruction of peat, the leading role belongs to solid particles with a diameter of less than 2.5 μm (PM_2.5). Even though the CO content in the air of the inoculation chambers was close to the maximum permissible level in the air of the working area, in combination with PM_2.5 and other gases of the smoke fraction, the occurrence of a potentiation of the toxic effect is likely.

Limitations. The study is limited to examining behavioral and electroencephalographic parameters in male albino rats exposed to peat smoke for 4 hours.

Ethics. The study was carried out in compliance with the principles set out in the European Convention for the Protection of Vertebrate Animals used for Experimental and other Scientific Purposes ETS N123, GOST 33215-2014 and approved by the Ethics Committee of the East Siberian Institute of Medical and Ecological Research (Protocol No. 7 dated December 15, 2023).

Contributions:
Vokina V.A. — concept, data collection, formal analysis, manuscript creation and editing, data administration;
Sosedova L.M. — concept, methodology, literature search, manuscript writing and editing;
Rukavishnikov V.S. — concept, methodology, administration.
All co-authors — approval of the final version and responsibility for the integrity of all parts of the manuscript.

Funding. The study was carried out according to the research plan within the framework of the state assignment.

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

Received: 27.03.2025 / Accepted: 14.04.2025 / Published: 08.05.2025

Hypersensitivity pneumonitis (HP) is an interstitial lung disease characterized by an immunological reaction of the lung parenchyma in response to certain antigens in a susceptible individual. According to the literature, the prevalence of HP is 1–4 cases per 100 thousand population. Identifying HP is a complex task and requires an integrated approach with the participation of different specialists, since currently there is no "gold standard" for its diagnosis. A clinical observation of a patient with HP that developed against the background of his professional activity is presented. Incomplete taking of the patient's medical history and insufficient consideration of the possible influence of work environment factors on the onset of the disease led to a delay in getting a correct diagnosis and prescribing appropriate treatment.

Contributions:
Pavlyukova M.V. — research concept and design, data collection and processing, text writing, editing;
Tikhomirova O.A. — data collection and processing, editing;
Frangu R.K. — data collection and processing, editing;
Stafeev A.N. — research concept and design, text writing, editing;
Mirzakhamidova S.S. — research concept and design, data collection and processing, editing;
Neklyudova G.V. — concept and design of research, editing;
Rachina S.A. — research concept and design, text writing, editing;
Avdeev S.N. — research concept and design, text writing, editing.

Funding. The study had no funding.

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

Received: 27.02.2025 / Accepted: 01.04.2025 / Published: 08.05.2025

The article provides a brief historical overview of the work of the Gorky Research Institute for Hygiene and Occupational Pathology (at present, the Federal Budgetary Scientific Institution "Nizhny Novgorod Research Institute for Hygiene and Occupational Pathology" of Rospotrebnadzor) during the Great Patriotic War of 1941-1945. It describes the work of the organization at the plants of the Dzerzhinsky Chemical Complex, which produced large volumes of toxic, flammable and explosive substances during the Great Patriotic War, as well as the peculiarities of the scientific activity of the Institute at the defense engineering enterprises located in the Gorky Region.

Apart from the description of the practical work of the Institute, the article provides data on the scientific work of the Institute, which did not stop even in the difficult conditions of wartime. It presents data on the organization by the Institute of a series of scientific and practical conferences during the war, the ultimate goal of which was the fastest possible implementation of the results of scientific developments of the Gorky Research Institute for Hygiene and Occupational Pathology employees into practice. The article gives information on the scientific publications published during the Great Patriotic War, as well as on thesis defense for academic degrees by the Institute's scientific staff.

Contributions:
Umnyagina I.A. — concept of the article, editing;
Kolesov S.A. — collecting and processing data, editing;
Fedotova I.V. — collecting and processing data, editing;
Lavrentyeva S.M. — collecting and processing data, editing.

Funding. The study had no funding.

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

Received: 14.03.2025 / Accepted: 16.04.2025 / Published: 08.05.2025