Introduction. The issues of radiofrequency electromagnetic field in near field human body exposure correct assessment and control methods improvement actualization determined the need to develop a predictive model that provides different exposure conditions in terms of their biological equivalence comparison.

Materials and methods. The problem of laboratory rats and humans equivalent EMF exposure assessment in near and far fields was considered. It is proposed to use a set of criteria that include both the power absorption in the irradiated objects values and the exposure time, allowing to take into account the peculiarities of human body and animals species sensitivity to this factor to solve this problem.

Results. Relations for RF EMF equivalent levels values calculation for concrete biological object in near and far fields are presented. There are presented the ratio to calculate EMF levels in terms of power density and energy exposure to case of human body exposure that is equivalent to experimental conditions of rats exposure.

Discussion. The developed model can be used to compare the experimental conditions of exposure in the near field with PD values for far field (formed electromagnetic wave), which is most important for >300 MHz frequencies, as well as for the interpretation of EMF biological effects obtained in animal experiments to human exposure conditions assess. This provides a biologically based approach to control RF EMF intensity at any distance from the source and the comparison of the field strength levels with the PD values in the zone of the formed electromagnetic wave.

Conclusion. The proposed model takes into account the physical patterns of energy absorption in different objects and differences of organisms species sensitivity to factor exposure; provides the ability to predict critical levels of irradiation for different human body organs and systems, taking into account the time of the factor exposure too.

Introduction. Metabolic syndrome (MS) is currently considered as aninterdisciplinary medical problem, which is due to its wide prevalence and interrelation with the development of cardiovascular diseases and type 2 diabetes. It is of interest to study the combination of MS and respiratory diseases due to their common pathogenetic mechanisms.

Objective is to assess an importance of studying MS in patients with occupational respiratory diseases and a possibility of using laboratory parameters as risk markers for developing occupational respiratory diseases and metabolic syndrome combination.

Materials and methods. The results of examination of 257 patients with occupational bronchopulmonary pathology were analyzed. Additional tests in patients with occupational asthma (OA) included levels of serum leptin and polymorphisms of inflammatory process regulation genes (interleukins–4, 6, 10, tumor necrosis factor-α, C-reactive protein (CRP), leptin receptor).

Study results and discussion. MS was detected in 58.7% of patients with occupational bronchial asthma (OA), in 44.1% of patients with occupational chronic bronchitis, in 48.6% of patients with occupational COPD, and in 38.7% of patients with pneumoconiosis. MS components appeared to be associated with respiratory function parameters. Role of Gln223Arg polymorphisms of leptin receptor gene and C3872T of CRP gene in development of leptin resistance has been confirmed. Findings are that genotype CC (C174G) of IL–6 gene gets 2.5-fold increase of MS development risk (OR=2.507, 95% CI=1.045–6.017), the presence of three or more cytokine gene polymorphisms 2.4 times increases the need to use systemic steroids to control OA (OR=2.449, 95% CI=1.127–5.324).

Conclusion. Measures aimed to prevent the development of metabolic disorders in workers exposed to industrial aerosol are at the same time measures to reduce the risk of developing respiratory diseases and to prevent progression of existing diseases. Using informative laboratory markers can optimize treatment and preventive measures, taking into account the individual characteristics of the organism.

Introduction. Mechanism underlying development of occupational bronchial asthma (OA) caused by exposure to polyvinyl chloride (PVC) aerosols is not completely clear. Complex properties of PVC aerosols components indicate possible development of OA among workers via both non-immune and immune mechanisms.

Objective is to study clinical and genetic characteristics of occupational bronchial asthma development at meat packers’ workplace.

Materials and methods. Examination covered 113 male and female meat-processing plant workers. A group (48 people) appeared to have daily contact with toxic-allergenic aerosols which were released as a smoke into the working area from molten PVC membrane during the meat products packing. All the examinees underwent clinical and functional tests of bronchopulmonary system and molecular genetic studies: identification of hyposecretory alleles of α–1IP gene; determination of genetic polymorphism of GSTM1 and GSTT 1.

Results and discussion. The study proved that exposure to PVC degradation products causes irritation and sensitization of the respiratory tract, visible mucous membranes and skin. The examinees with 5–10 years of service demonstrated reversible obstructive pulmonary ventilation disorders with bronchial hypersensitivity to occupational factors (30 people) and symptoms of bronchial asthma (18 people) of immune and non-immune origin. The asthma phenotypes were determined: occupational — immune and non-immune (11 people) and aggravated by work conditions (7 people). The study proved that individual risk factors of occupational bronchial asthma in meat-packers are: hyposecretory PiMZ variant of α1-PI gene and deletion of glutathione-S-transferase genes (GSTM1 and GSTT 1). The findings prove that meatpackers’ asthma is a multifactorial disease.

Conclusion. Hyposecretory alleles of α1-PI gene appeared to participate in occupational bronchial asthma development. Identified relationships between hyposecretory variants of α1-PI gene, null alleles of glutathione-S-transferase genes (GSTM1 and GSTT 1) carriage, occupational bronchial asthma development and severity suggest that meat-packers’ asthma is a multifactorial disease. This could be an explanation of various phenotypes of occupational bronchial asthma. Problem of occupational bronchial asthma development due to influence of PVC pyrolysis products necessitates further wide clinical, hygienic and molecular genetic studies.

Introduction. Occupational environment and occupational factors determine peculiarities in mastering marine occupations. Some unfavorable occupational educational and ecologic factors appear to cause high level of physical and psychoemotional stress.

Objective is to study features of adaptation to study during occupational training in marine specialties in cadets of a higher marine educational institution, and to conduct medical and psychological rehabilitation.

Material and methods. Examination covered 120 male cadets of 3rd and 4^th years of study: 70 (main group) and 50 (reference group). The age of the cadets was 21±0.4 years. To study characteristics of the cadets’ adaptation, the authors used psychological methods — Spielberger’s State Trait Anxiety Scale and Nemchin’s «Method measuring severity of neuropsychic stress». Statistical analysis was performed with software «Statistica for Windows 10.0».

Study results and discussion. After 3 months of sailing, majority of the cadets appeared to be dysadapted. Deep clinical and laboratory studies proved that 39.4% of the examinees were apparently healthy and 60.6% of those had chronic diseases. Thus, a system of medical psychologic rehabilitation was designed, comprising primary and secondary prophylaxis methods. One of these prevention methods is a recovery complex of measures with intermittent normobaric hypoxia modified by us. The authors determined optimal regime of using intermittent normobaric hypoxia combined with medical rehabilitation.

Conclusions. Adaptational state in cadets of high marine educational institution during professional training in marine occupations is characterized by increased psycho-emotional strain, anxiety and observed in 57.3% of the examinees. Findings are that after 3 months of sailing, majority of the cadets are dysadapted. To prevent morbidity and preserve health, the authors suggested a system of medical and psychologic rehabilitation including intermittent normobaric hypoxia with rehabilitation medical complex. The medical and prophylactic measures help to solve problems of psycho-emotional stress, lower morbidity parameters, prevent dysadaptation disorders, relieve functional overstrain. That preserves and improves the cadets’ health and forms an important stage in prevention of mental and behavioral disorders related to work.

For preparation to ratification of ILO Convention No 188 “On work in fishing sector” by Russian Federation, the authors analyzed national and foreign data on work conditions, occupational and general diseases, occupational traumatism among fishermen. General theses of the Convention were considered in their correspondence to legislation and regulation basis of RF. Suggestions to improve health preservation system in fishing industry were justified.

Introduction. Special evaluation of work conditions sometimes fails in identifying biologic factor as an occupational hazard in work with infected and (or) potentially infected materials (including field, clinical, autopsy samples) suspicious for presence of pathogenic biologic agents, as well as considering allergic component in biologic factor’s influence on workers exposed.

Objective is to improve methods of identification and evaluation of biologic factor, criteria and classification of work conditions for workers exposed to pathogenic biologic agents, for more objective assessment of their work conditions.

Materials and methods. Based on Rospotrebnadzor data, the authors analyzed occupational morbidity caused by exposure to biologic factors over 2005–2017. Analysis also covered work conditions of workers exposed to biologic factors, according to results of workplace certification by work conditions, performed by Testing Laboratory FGBNU «NII MT» over 2001–2013 at 1024 workplaces of medical and non-medical personnel in medical institutions of Moscow, 26 workplaces of FGBNU «N.F. Gamaleya National Research Institute of epidemiology and microbiology» with RF Health Ministry, 32 workplaces in purification facilities MGUP «Promotkhody». Analysis of the work conditions over 2014–2017 was based on results of special evaluation of work conditions at 326 workplaces (data by FGBNU «NII MT»).

Results and discussion. The authors scientifically justified ways to improve quality and adequacy of work conditions evaluation by biologic factor at workplaces of individuals exposed to biologic pathogens. To objectify the work conditions evaluation by biologic factor, the authors suggested a «Classification of work conditions under exposure to biologic factor» that helped to identify and evaluate health risks with consideration of all biologic objects at the workplaces.

Conclusion. Suggested «Classification of work conditions under exposure to biologic factor» helps to identify and evaluate biologic factor as an occupational hazard at all workplaces with pathogenic microbes, as well as analyze occupational health risks for workers and justify measures to minimize those risks.

Introduction. Evidences prove falseness of formula determining maximal allowable level of total energy of laser irradiation in case when eyes or skin are simultaneously exposed to several irradiation sources with various wavelengths. The formula was mentioned in actual «Sanitary rules and regulations for lasers construction and exploitation» Nо 5804–91 and in SanPiN 2.2.4.3359–16, that in a part of VIII section «Laser irradiation atworkplace» are latest acting regulation document on laser safety. SanPiN 2.2.4.13–2–2006 of Belarus Republic and regulation document Nо 299 of Customs Union Commission of Eurasia Economic Community on 28/05/2010 appeared to contain other, more correct formula determining the same maximal allowable level.

Objective was to improve regulation basis in laser safety by correcting mistakes made previously in regulation documents.

Deducing formulae. The article presents thorough and consistent deducing a formula to determine total energy of laser irradiation in case when eyes or skin are simultaneously and jointly exposed to several irradiation sources with various wavelengths. The efforts resulted in the formula that agreed with formulae presented in the regulation document on laser safety of Belarus Republic and in the regulation document Nо 299 of Customs Union Commission of Eurasia Economic Community on 28/05/2010.

Discussion. Correctness of the obtained formula is supported by numerical examples and by comparison with other formulae used in regulation documents on hygienic regulation of other acting factors.

Conclusion. Results of the work are summarized, and emphasis is made on its value for solving problems of improving regulation basis for laser safety.

Respiratory system diseases are one of the main problems in contemporary occupational medicine and exceed one fifth of all occupational diseases. Objective of the review was search and analysis of literature on diagnosis of silicosis as an important occupational disease of respiratory organs, by computed tomography and high-resolution computed tomography, from evidence-based medicine viewpoint.

Objective was to evaluate influence of work conditions on clinical and epidemiologic manifestations of tuberculosis in workers engaged into extraction and processing of uranium ores.

Materials and methods. Retrospective study with total sampling method covered tuberculosis cases in working inhabitants of Krasnokamensk town in Zabaikalsk region, aged 20–60 years (2005–2015). Formed sample (n=94) was divided into two groups: main group — workers of uranium-extracting enterprise (n=40), reference group — workers of enterprises not connected with uranium production (n=54). In the groups analyzed, the study covered longstanding dynamics of morbidity and clinical manifestations of tuberculosis process. Evaluation also included tuberculosis risk in workers of uranium production, in dependence on levels of radiation exposure and length of service.

Results. Higher average long-term level of tuberculosis morbidity was proved to be characteristic for the uranium production workers (Me=70.10/0000 [40.2–115.5]), not depending on level (Me=13.20/0000 [9.7–31.8]) and trend of morbidity among working inhabitants of the town (rs=0.382; p=0.247). Tuberculosis process has more unfavorable clinical manifestations in the uranium production workers with higher level of radiation exposure (group A personnel). Among them, more frequent discharge of the causative agent, in comparison with workers suffering from tuberculosis and having less level of radiation exposure (group B personnel) (52% and 16% respectively; p=0.022). Th e maximal tuberculosis risk was demonstrated for group A personnel with length of service from 5 to 15 years (OP=2.7 [1.1–7.0]).

Conclusion. Work conditions of uranium enterprise workers have negative influence on tuberculosis morbidity level and result in highly contagious types of tuberculosis.

Introduction. Topicality of the study is associated with necessity of physiologic, hygienic and ergonomic basis for methods evaluating tolerance of individual protective means.

Objective is to study possible use of contemporary facilities and investigation methods for functional state of humans and their performance within physiologic, hygienic and ergonomic assessment of individual protective means.

Methods. The authors used analytic methods and considered methodic issues connected with evaluation of human functional state and performance.

Results. Findings are that present regulation basis evaluating influence of individual protective means on human functional state does not consider contemporary novelties in medical equipment, is outdated and requires improvement. The authors justified selection of methods that improve approaches to evaluation of individual protective means in simulated and real industrial conditions. Evidences are that medical and biologic evaluation of individual protective means should study functional state of locomotory system, cardio-respiratory and nervous systems. Ergospirometry is the most informative method to evaluate functional state of cardio-respiratory system, “movements capture” by inertial sensors is the most applicable method to evaluate influence of individual protective means on workers’ mobility, and stabilometry can add existing methods evaluating influence of individual protective means on locomotory and nervous systems.

Conclusions. The studies performed can serve as a basis for improvement of prospective methods of physiologic, hygienic and ergonomic evaluation of individual protective means.

More workers are involved into interaction with graphic user interfaces most part of the working shift. However, low ergonomic qualities or incorrect usage of graphic user interface could result in risk of unfavorable influence on workers’ health. The authors revealed and classified typical scenarios of graphic user interface usage. Various types of graphic user interface and operator occupations are characterized by various parameters of exertion, both biomechanical and psycho-physiological. Among main elements of graphic user interface are presence or absence of mouse or joystick, intuitive clearness, balanced palette, fixed position of graphic elements, comfort level, etc. Review of various graphic user interface and analysis of their characteristics demonstrated possibility of various occupational risk factors. Some disclosed ergonomic problems are connected with incorporation of graphic user interface into various information technologies and systems. The authors presented a role of ergonomic characteristics of graphic user interface for safe and effective work of operators, gave examples of algorithms to visualize large information volumes for easier comprehension and analysis. Correct usage of interactive means of computer visualization with competent design and observing ergonomic principles will optimize mental work in innovative activity and preserve operators’ health. Prospective issues in this sphere are ergonomic interfaces developed with consideration of information hygiene principles, big data analysis technology and automatically generated cognitive graphics.

The authors presented new forms of professional training for specialists in occupational medicine (network type of running educational programs, electronic education and distant training technologies, etc.), based on continuous training concept with module system and creation of competency approach.

Introduction. Typology of diurnal (circadian) human rhythms is actively studied in occupational medicine, from the viewpoint of adaptation to various work conditions including those with shift working schedule. In recent years, evidences outline bimodal chronotype characterized by simultaneously present signs of extreme morning and extreme evening types without dominating one of them. Studies did not cover bimodal chronotype in night-shift workers.

Objective is to evaluate presence of bimodal chronotype in night-shift workers if compared to day-shift schedule.

Materials and methods. Chronotype outlining covered 95 workers divided into 2 groups: first — 55 night-shift workers, second — 40 workers on day schedule. Bimodal chronotype was diagnosed via algorithm based on questionnaire Morningness Eveningness Questionnaire (MEQ) by B.J. Martynhak et al.

Results. Findings are that 7.3% of night-shift workers and 5.0% of workers with day schedule demonstrate bimodal chronotype. Changed chronotype classification leads to smaller share of workers with intermediate chronotype, but quota of morning and evening chronotypes does not change. Possibility of bimodal chronotype should be respected in examination of workers for designing health programs with consideration of chronotype-associated diseases and for better performance due to rational management of working time.

Conclusions. Diagnosis of individual chronotype is a serious part in health programs formation in able-bodied population. Chronotype knowledge helps to minimize possible decrease and losses of performance due to rational working time management and preventive programs aimed to diagnose chronotype-associated health disorders.