Introduction. The high risk of infection of healthcare workers dictates the need to study their working conditions during the COVID-19 pandemic.

The study aims to research the working conditions of medical workers during the COVID–19 pandemic in multidisciplinary medical and preventive organizations.

Materials and methods. Analysis of working conditions of medical workers of medical and preventive organizations. The study design is a closed population (four medical institutions were randomly selected), a target group (doctors and nurses). The authors analyzed the staffing table and 16 reports on a special assessment of working conditions at 1,251 workplaces (1,845 medical workers, of which 787 doctors, 1,058 nurses). Statistical analysis included: standard methods of descriptive statistics, determination of relationships by logistic regression (odds ratios (OR) and 95% confidence intervals (OR CI)). p<0.05 was taken as the critical level of significance.

Results. The largest number of ill medical workers provided assistance to patients without signs of COVID-19 both in hospitals (86.06% of doctors, 85.85% of nurses) and in outpatient polyclinic treatment and prevention organizations (90.31% of doctors, 92.05% of nurses). The probability of getting sick COVID-19 was maximum in an infectious diseases hospital (compared with emergency departments OR 2.049; 95% OR CI 1.194–4.608 and diagnostic and treatment units of medical institutions OR 3,057; 95% OR CI 1,876–4,98). The workplaces of medical workers who have undergone COVID-19 in infectious diseases hospitals and specialized teams are classified as harmful class 1–3 degrees, and workers are classified as high occupational risk groups according to SARS-CoV-2. The probability of getting sick with COVID-19 is significantly higher when in contact with pathogens of infectious diseases (class of working conditions 3.3 compared to 3.1 or 3.2).

Conclusion. The workplaces of medical workers who have undergone COVID-19 in infectious diseases hospitals and specialized brigades are classified as harmful class of the first to third degree, and workers are classified as high occupational risk groups for COVID–19.

Ethics. Scientists have conducted the study in compliance with the Ethical principles set out in the Helsinki Declaration of 1975 with amendments of 1983 and obtaining the informed consent of patients.

Contribution:
Shpagina L.A. — research concept and design, writing the text;
Kotova O.S. — writing the text;
Likhenko-Logvinenko K.V. — data collection and processing, writing the text;
Astrakov S.V. — data collection and processing;
Kalinichenko A.V. — data collection and processing;
Gerasimenko O.N. — data collection and processing;
Karmanovskaya S.A. — data collection and processing;
Chebykin D.V. — data collection and processing;
Kuzmina L.P. — writing the text;
Bukhtiyarov I.V. — writing the text.
All the authors — have made a significant contribution to the search and analytical work and the preparation of the article.

Gratitude. The authors are grateful to teams of City Clinical Hospital No. 2, Novosibirsk, City Clinical Hospital No. 25, Novosibirsk, SBHI of the Novosibirsk Region "Clinical consultative and diagnostic polyclinic No. 27", Hospital for War Veterans No. 3 for help in conducting the study.

Funding. The study had no funding.

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

Received: 30.03.2023 / Accepted: 10.04.2023 / Published: 05.05.2023

Introduction. With the growth of urbanization processes, the problem of professional exposure to electric and magnetic fields of industrial frequency is an increasingly relevant topic. Recently, the scientists paid a special attention to the long-term health consequences associated with prolonged exposure to harmful physical factors. The previously obtained data on the increase in the levels of lipid metabolism and hormonal and metabolic disorders in workers exposed to electric and magnetic fields of industrial frequency determine the relevance of studying adipokine metabolism and assessing genetic risk factors for predisposition to cardiovascular pathology in employees of the electric power industry.

The study aims to research the relationship of biochemical and molecular genetic markers of adipokine metabolism with indicators of hormonal and metabolic disorders for a comprehensive assessment of cardiovascular risk in workers exposed to electric and magnetic fields of industrial frequency.

Materials and methods. The researchers examined 144 employees of the main group engaged in the repair and operation of power grid facilities and 40 employees of the control group who are not exposed to electromagnetic fields of industrial frequency.The concentration of leptin and adiponectin was determined in blood serum samples. The authors have calculated the ratio of adiponectin to leptin. We have performed a molecular genetic study of single nucleotide polymorphisms of leptin (LEP) G2548A (rs7799039), leptin receptor (LEPR) A668G (rs1137101) and adiponectin type two receptor (ADIPOR2) G795A (rs16928751) genes.

Results. The staff of the main group revealed a higher level of leptin (8.1 (3.7; 14.4) ng/ml) relative to the same indicator in the control group (6.0 (4.1; 11.1) ng/ml), p<0.028. Levels of leptin and adiponectin moderately and weakly correlate with hormonal and metabolic parameters. In the group of employees with less than 10 years of experience, a higher level of adiponectin was established compared to the group with 11–20 years of experience (6.1 (4.6; 9.1) mcg/ml and 4.5 (3.6; 6.4) mcg/ml, respectively); with an increase in work experience of more than 20 years, a significant increase in the concentration of leptin was found (p<0.05). Scientists have identified the significance of single-nucleotide polymorphisms of the LEPR, LEP, ADIPOR2 genes in the development of abdominal obesity, an increase in cholesterol levels and a decrease in the level of total testosterone in workers exposed to electric and magnetic fields of industrial frequency.

Limitations. The study is limited to the number of surveyed (144 employees).

Conclusion. The results of the study indicate the relationship of biochemical and molecular genetic markers of adipokine metabolism with indicators of hormonal and metabolic disorders in employees exposed to electric and magnetic fields of industrial frequency. When examining workers exposed to electric and magnetic fields of industrial frequency, the use of clinical and laboratory markers of adipokine metabolism (biochemical, molecular genetic) is informative in a comprehensive assessment of cardiovascular risk.

Ethics. The work complies with ethical standards developed in accordance with the Helsinki Declaration of the World Medical Association "Ethical Principles of conducting Scientific medical research with human participation" as amended in 2000 and the "Rules of Clinical Practice in the Russian Federation" approved by Order of the Ministry of Health of the Russian Federation No. 200n dated 01.04.2016. Informed consent to participate in the study was received from each of the surveyed, approved in accordance with the established procedure by the local ethics committee of Izmerov Research Institute of Occupational Health (minutes of the meeting of the Ethics committee of Izmerov Research Institute of Occupational Health No. 4 dated 12/25/2013).

Contribution:
Kislyakova A.A. — research concept and design, data collection and processing, text writing;
Kuzmina L.P. — concept and design of the study, editing;
Khotuleva A.G. — concept and design of research, writing, editing;
Bezrukavnikova L.M. — editing.

Funding. The study had no funding.

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

Received: 03.04.2023 / Accepted 13.04.2023 / Published 05.05.2023

Introduction. The work of medical personnel in the extreme conditions of the COVID-19 pandemic is related to the impact of nervous and emotional labor tension, high visual loads, which contributes to the formation of fatigue and overwork and requires the attention of labor physiologists.

The study aims to substantiate the methodology of physiological assessment of functional fatigue of medical workers during work in a covid hospital to determine the duration of periods of work in a pandemic.

Materials and methods. Comprehensive physiological and hygienic studies of the medical staff of the covid hospital during 6 months of work were aimed at a physiological study of the state of the cardiovascular system with the study of the characteristics of the response to stress loads (ECG registration on a 12-channel electrocardiograph and continuously using Holter monitoring, determination of the vegetative Kerdo index and Kvass endurance coefficient), the study of psychological conditions, hygienic assessment of the intensity of the labor process. The researchers have studied the physiological state of the central nervous system and the visual analyzer according to generally accepted methods. The authors have studied the features of neurohumoral regulation (the main mediator of the stress-implementing system — cortisol) in medical workers. We have carried out a total of 1728 measurements of psychophysiological indicators. The scientists carried out statistical data processing of the received data using statistical programs Statistika 10, Microsoft Excel 2010.

Results. The researchers found that indicators of the functional state of the cardiovascular system, reflecting the degree of adaptation of the body of medical workers to industrial activity, can be used to determine physiologically justified work periods in a pandemic, further accumulation of scientific data and risk assessment of medical workers. After four months of work in medical organizations with COVID-19, the formation of an unfavorable functional state in medical personnel is reflected in changes in ECG and systemic blood pressure, increased detrenability of the cardiovascular system, the predominance of sympathetic influences.

Limitations. There are quantitative restrictions due to the number of medical staff of the  hospital with COVID-19.

Conclusion. Pronounced loads on the visual analyzer when watching video terminal screens against the background of nervous and emotional labor tension are the leading professional factors and determine the formation of the functional state of overwork (third degree) in the medical staff of the hospital with COVID-19.

Ethics. The study was approved by the Local Ethics Committee of the Izmerov Research Institute of Occupational Health (Protocol No. 4 of 04/14/2021).

Contribution:
Bukhtiyarov I.V. — concept and design of the study;
Zaitseva A.V. — data collection and processing, text writing;
Serikov V.V. — concept and design of the study;
Yushkova O.I. — writing, editing;
Kapustina A.V. — data collection and processing, analysis of material on medical personnel;
Forverts A.Yu. — editing.

Funding. The study had no funding.

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

Received: 07.04.2023 / Accepted: 12.04.2023 / Published: 05.05.2023

Introduction. When performing work in open areas in the summer, electrical engineering personnel use shunt shielding kits to protect against industrial frequency electric fields. However, the use of personal protective equipment has an additional thermal load on the human body, which is assessed, among other things, by changes in the indicators of the functional state of the cardiovascular system.

The study aims to assess the variability of the heart rate when working in shunting screening kits under conditions of modeling the thermal load of the environment.

Materials and methods. The study carried out in seven volunteers using power frequency electric field personal protective equipment. Heart rate variability assessed for simulated elevated thermal load environment. The volunteers worked with physical activity (walking) of 60 minutes treadmill and 15 minutes rest in the same climatic conditions (recovery period) after. Temperature and humidity inside shunting shielding personal suit recorded. The determination and statistical analysis of heart rate variability based in electrocardiogram were performed. Based on the recording of an electrocardiogram, the authors carried out the determination and statistical analysis of heart rate variability indicators.

Results. Volunteers heart rate variability analysis showed that stress index median values during work and recovery periods were 345 cu and 96 cu without shunting shielding personal suit. Work in shunting shielding personal suit showed that stress index median values were 196 cu and in recovery period 152 cu. RR-interval median values under work in personal protective equipment were lower (0.552 s) than without personal protective equipment (0.617 s). The results revealed the tendency to body thermoregulatory mechanisms strain increase in work time, characterized by RR-intervals differences with personal protective equipment use and without (ΔRR) — 0.057 s, and organism partial recovery during rest time (ΔRR — 0.113 s) with personal protective equipment.

Limitations. The number of volunteers was due to the limited duration of the study.

Conclusion. The results of cardiovascular system functional state assessment by heart rate variability indicate stress with regulatory systems overstrain with and without personal protective equipment. Power frequency electric field personal protective equipment makes additional external thermal load to human body as stress index (196 cu), RR-intervals (0.552 s) in work period and slight decrease in recovery period (152 cu and 0.566 s). Stress index high values in the recovery period associated with prolonged environment thermal load exposure due to climatic parameters and volunteers staying in PPE after the end of physical work.

Ethics. The Local Ethics Committee of the Izmerov Research Institute of Occupational Health approved this study carried out under the WMA Declaration of Helsinki (record № 3 from 23.03.2022).

Contribution:
Perov S.Yu. — concept, design and organization of research;
Sazhina M.V. — collecting material and data processing, writing tex;
Konshina T.A. — collecting material and data processing, writing text;
Levchenkov D.I. — data processing, text writing.

Funding. The study had no funding.

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

Received: 24.04.2023 / Accepted: 25.04.2023 / Published: 05.05.2023

A systematic review, combining analysis (on means after deleting outliers from samples) and meta-analysis for Standardized mortality ratio (SMR) versus the general population for total and all-cancer mortality for professional drivers (men only) of various countries (cohorts of Great Britain, Denmark, Iceland, Italy, Canada, Russia, Singapore, Switzerland and Sweden (1988–2002); data for the USA (1978) were not available; 13 papers in total) were conducted. The criteria for the search and selection of sources (PubMed, Google, Cochrane Systematic Reviews and reference lists of publications) were: a) a cohort of drivers only, without adding other employees of auto enterprises; b) the presence in the study of index of total mortality (‘all causes’) and/or mortality from all malignant neoplasms (‘all cancer’); c) the expression of mortality rates only in the SMR index.

A combined analysis and meta-analysis showed a weak healthy worker effect (HWE; meta-analysis: SMR=0.92, 95% confidence intervals (CI): 0.85, 0.99, the presence of HWE was judged by the value of the upper CI<1.0). There are also trends towards HWE for overall mortality for taxi and truck drivers (SMR=0.9–0.93), but the samples are too small to draw conclusions. For other groups of drivers HWE was not found.

In both types of synthetic studies, no SMR for HWE was observed for mortality from all malignancies, either for the general group of drivers (8 countries; 16 cohorts) or for individual occupational groups. There were slight increases in SMR (by 3–10%), the magnitude of which, according to epidemiological canons, is difficult to prove, and according to the risk scale by R.R. Monson corresponds to no effect.

The absence of significant risks both in terms of the integral indicator of well-being (life expectancy, inversely proportional to SMR), and in terms of mortality from all types of malignant neoplasms for professional drivers makes it unlikely that the population of Russia will experience increased mortality due to ever-increasing mass motorization.

Contribution:
Koterov A.N. — the concept and design of the study, data collection and processing, writing the text, editing;
Ushenkova L.N. — data collection and processing, editing.

Funding. As part of the broader budget theme of the FMBA of Russia; without other sources of funding and sponsorship.

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

Received: 17.01.2023 / Accepted: 24.01.2023 / Published: 05.05.2023

In metrology, measurement uncertainty is an expression of the statistical variance of values attributed to a measured quantity. All measurements are subject to uncertainty, and the measurement result is complete only when it is accompanied by data on the uncertainty associated with it. The scientists have considered the main provisions of the current regulatory and methodological documents on the problem of accounting for uncertainty values when measuring physical factors of a non-ionizing nature and evaluating their results. In particular, the fundamental in terms of the definition and application of measurement uncertainty GOST 34100.1–2017/ISO/IEC Guide 98-3:2008 is considered in detail. The authors highlighted the issues of taking into account measurement uncertainty in the hygienic assessment of physical factors of the production environment, including the rules for evaluating measurement results taking into account uncertainty, a list of certified methods for measuring physical factors in the workplace indicating the parameters of extended uncertainty, ways to reduce uncertainty.

Funding. The study had no funding.

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

Received: 03.04.2023 / Accepted: 20.04.2023 / Published: 05.05.202

The use of personal protective equipment (PPE) is one of the ways to preserve the health of employees in adverse working conditions. PPE remains one of the key tools for minimizing the impact of harmful and dangerous factors. Scientists create and use PPE to reduce accidents, serious injuries, poisoning, the likelihood of developing professionally caused, occupational diseases that often remain undetected. It is important to use PPE efficiently by employees of various industries. The effectiveness of their use in the workplace largely depends on the right choice, the employer's awareness of the risks, training in ways to check the serviceability, correct use, control. The lack of training or its insufficiency leads to inevitable mistakes in the selection and application of PPE. Unfortunately, not all existing PPE are effective enough, because they are not always of proper quality, are not individually selected, and are not able to give warning signals about the presence of danger. Employees should take into account that PPE can create: harmful and sometimes dangerous inconveniences for health; a false sense of security in case of improper use, loss of efficiency in case of incorrect storage or maintenance; complicate working conditions. The correct use of PPE depends on the behavior of the worker. It is advisable to take into account the nature of labor operations and the severity of the work performed; the protective properties of PPE, depending on the type and quality of materials used for their manufacture; product design. Competent selection of PPE, compliance with the terms of their operation can reduce professional risks. To date, specialists have developed modern "smart" PPE, as well as intelligent systems to improve the efficiency of existing PPE.

Funding. The study had no funding.

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

Received: 03.04.2023 / Accepted: 21.04.2023 / Published: 05.05.2023