Provision of healthy and active longevity is among the most significant trends in the scientific and technical development of the Russian Federation. In this respect, it is highly relevant to perform hygienic assessment of health hazards posed by new materials, nano-sized ones included. At present, materials containing zinc and copper nanoparticles (NPs) are being used more and more widely; this goes for both an alloy (Cu-Zn) or using their oxides separately (CuO, ZnO). This results in exposure involving human health risks. Preliminary assessment revealed high potential hazard posed by Cu-Zn NPs due to, among other things, modified cytotoxicity relative to microparticles (MPs) of its chemical analogue because of the nano-sized phase as well as relative to isolated NPs, which is associated with interaction between the two elements upon combined administration into the body. This necessitates investigations with their focus on comparative assessment and analysis of modified cytotoxicity of the Cu-Zn NPs alloy relative to MPs and isolated NPs in vivo. The study was performed on Wistar rats involving one-time intratracheal exposure to suspensions in the volume of 0.4 cm3, containing Cu-Zn, CuO, ZnO NPs or Cu-Zn MPs in the concentration of 0.013 g/cm3. Cytotoxicity was comparatively assessed 24 hours after the exposure per changes in the cell population in the bronchoalveolar lavage (BAL). Verification of physical properties confirmed that the tested materials contained NPs. Cu-Zn NPs differed from MPs per their size, specific surface area and total pore volume (up to 2118 times). Cytotoxic effects produced by isolated CuO and ZnO NPs were identified by growing levels of alveolar macrophages (1.9 times higher against the control); declining levels of neutrophil leukocytes, monocytes, lymphocytes and neutrophil to macrophage ratio (up to 3.5 times). Cu-Zn alloy NPs are more cytotoxic relative to MPs (up to 6.1 times) and isolated NPs (up to 29 times) as established per growing levels of neutrophil leukocytes and neutrophil to macrophage ratio and per declining levels of alveolar macrophages, monocytes, and lymphocytes. Therefore, the study confirms serious health hazard posed by copper- and zinc-containing NPs, which is manifested, among other things, as cytotoxic effects upon intratracheal exposure in vivo. Cytotoxic effects become stronger upon exposure to Cu-Zn alloy NPs relative to MPs due to the nano-sized phase and relative to isolated NPs due to synergy between the two elements. These findings enrich hygienic concepts about cytotoxicity of copper- and zinc-containing NPs upon isolated and combined exposure in vivo, which makes it possible to provide more effective scientific substantiation for preventive measures and mitigating health risks for exposed population.

Within this study, a phenomenological mathematical model has been developed and parameterized; it is based on the system of evolution equations and designed for quantification of effects produced by age on population cancer risk. The model describes risk dynamics as the function of likelihood of cancer and its severity relying on retrospective population data. The 10th percentile of incidence per administrative territories was used to identify the background age-related component cleared from influence of local carcinogenic factors. The equation parameters were estimated by the least square method. The model parameterization revealed considerable inter-nosology variability in key parameters, which reflected specific features of pathogenesis of different tumor types. Analysis of age-related dynamics in the risk structure revealed that contributions made by specific nosologies were re-distributed systemically. We established progressive predominance of malignant neoplasms of the digestive system in the cancer risk structure since they became the leading age-related pathology in older age groups. A parallel considerable decline was found as regards contributions made by other nosologies, breast cancer included. The resulting picture of age-related evolution of cancer risk shows a discrepancy from the conventional priorities in oncological care, which are often oriented at nosologies with high median incidence. The modeling results highlight the necessity to shift the attention focus on pathologies with the most intensive age-related risk and fatality accumulation. This primarily includes tumors of the digestive system since they make the major contribution to age-related cancer mortality, which is not fully considered within the existing approaches. This emphasizes the necessity to adapt preventive and screening strategies considering the biologically determined structure of population risk. The focus should be shifted on targeted gerontological oncology. The developed model adequately describes age-related carcinogenesis and provides solid basis for assessing additional risks caused by specific endo- and exogenous effects as well as for developing targeted gerontological oncological strategies.

Provision of healthy and active longevity is among the most significant trends in the scientific and technical development of the Russian Federation. In this respect, it is highly relevant to perform hygienic assessment of health hazards posed by new materials, nano-sized ones included. At present, materials containing zinc and copper nanoparticles (NPs) are being used more and more widely; this goes for both an alloy (Cu-Zn) or using their oxides separately (CuO, ZnO). This results in exposure involving human health risks. Preliminary assessment revealed high potential hazard posed by Cu-Zn NPs due to, among other things, modified cytotoxicity relative to microparticles (MPs) of its chemical analogue because of the nano-sized phase as well as relative to isolated NPs, which is associated with interaction between the two elements upon combined administration into the body. This necessitates investigations with their focus on comparative assessment and analysis of modified cytotoxicity of the Cu-Zn NPs alloy relative to MPs and isolated NPs in vivo. The study was performed on Wistar rats involving one-time intratracheal exposure to suspensions in the volume of 0.4 cm3, containing Cu-Zn, CuO, ZnO NPs or Cu-Zn MPs in the concentration of 0.013 g/cm3. Cytotoxicity was comparatively assessed 24 hours after the exposure per changes in the cell population in the bronchoalveolar lavage (BAL). Verification of physical properties confirmed that the tested materials contained NPs. Cu-Zn NPs differed from MPs per their size, specific surface area and total pore volume (up to 2118 times). Cytotoxic effects produced by isolated CuO and ZnO NPs were identified by growing levels of alveolar macrophages (1.9 times higher against the control); declining levels of neutrophil leukocytes, monocytes, lymphocytes and neutrophil to macrophage ratio (up to 3.5 times). Cu-Zn alloy NPs are more cytotoxic relative to MPs (up to 6.1 times) and isolated NPs (up to 29 times) as established per growing levels of neutrophil leukocytes and neutrophil to macrophage ratio and per declining levels of alveolar macrophages, monocytes, and lymphocytes. Therefore, the study confirms serious health hazard posed by copper- and zinc-containing NPs, which is manifested, among other things, as cytotoxic effects upon intratracheal exposure in vivo. Cytotoxic effects become stronger upon exposure to Cu-Zn alloy NPs relative to MPs due to the nano-sized phase and relative to isolated NPs due to synergy between the two elements. These findings enrich hygienic concepts about cytotoxicity of copper- and zinc-containing NPs upon isolated and combined exposure in vivo, which makes it possible to provide more effective scientific substantiation for preventive measures and mitigating health risks for exposed population.

An alarming trend is observed in recent years involving growing incidence of malignant neoplasms of the gastrointestinal tract. It appears to be associated with a non-hereditary etiology. Behavioral factors, lifestyle, nutrition, microbes, the environment and physiological mechanisms of the host may all play a key role in this. This prompted us to study risk factors causing development of malignant neoplasms. The aim of this study was to identify risk factors causing malignant neoplasms of the digestive organs in the Aral Sea region of Uzbekistan (the Republic of Karakalpakstan). These risk factors were established by conducting a case-control analytical epidemiological study involving 307 participants; of them, 151 were respondents with malignant neoplasms of the digestive system and 156 relatively healthy respondents. The study was conducted at the Karakalpakstan branch of the Republican Specialized Scientific and Practical Medical Centre for Oncology and Radiology of the Republic of Uzbekistan. The results of the study have determined that the leading risk factors causing development of digestive cancer are bad habits such as alcohol consumption of 500 ml/week or more (OR = 2.09), smoking 10 or more cigarettes per day (OR = 2.61) and being a current smoker (OR = 2.72). Smoking nasvay, which is common in Central Asia, is also a significant risk factor for digestive cancer in men (OR = 3.587). Dietary habits also play an important role, particularly the consumption of 500 g or more of red meat per week, which creates elevated risks of developing cancer of the digestive organs (OR = 2.08). The physiological balance of the human body determines its health state. Thus, abdominal obesity (OR = 2.24) and a history of being overweight (OR = 2.69) increase the risk of developing malignant neoplasms of the digestive organs. Additionally, the odds ratio (OR) for individuals who prefer hot tea is 1.31 (95 % confidence interval (CI): 0.83–2.07). According to our findings, psycho-emotional states such as stress following the loss of a loved one (OR = 3.25), work involving stressful tasks (OR = 2.84), intense work (OR = 2.17), sleep disorders or insomnia in the last six months (OR = 2.20), and prolonged depression (OR = 2.12) increase the risk of developing digestive cancer. All examined risk factors are manageable and each of them can be a target for primary prevention of malignant neoplasms of the digestive system.

We have examined influence exerted by eight microbiological and chemical environmental factors on mortality, primary incidence and disease prevalence per 19 disease classes in 45 municipalities in Tatarstan, including children, working age population and elderly people, over 2019–2023. The study aimed to identify priority environmental risk factors causing medical-demographic losses of the population per specific classes of diseases and nosologies in Tatarstan. The study tasks included establishing correlations between environmental and medical-demographic factors as well as their strength; building predictive regression models; assessing regression coefficients of additional mortality and morbidity risks. The results obtained by comparative analysis of influence exerted by ambient air, water and soil quality in Tatarstan confirmed the existing national trends in Russia as regards associations between mortality and morbidity and chemical pollution in ambient air, water supply deviating from the existing sanitary-epidemiological rules and standards, soils not conforming to safe standards per microbiological indicators; in addition, we established some health risks specific for Tatarstan. The greatest number of strong correlations was established for ambient air quality; a smaller number of medium correlations was established for water quality; the smallest number of correlations was established for soil quality. Children remain the most susceptible population group as regards primary incidence and disease prevalence. Multifactorial models established that additional risk of environment-associated incidence ranged between 44 and 67 % for children, equaled 57 % for working age population and 30 % for people older than working age per the existing mean morbidity rates per various classes of diseases. A strong direct correlation was established between incidence of neoplasms in children and the proportion of ambient air samples containing NO2 and NH3 in levels beyond the maximum permissible concentration; the same correlation was established between NH3 levels exceeding the maximum permissible concentration and prevalence/incidence of complications of pregnancy and childbirth among working-age women. Regarding mortality, we revealed correlations of varying strength; a strong non-linear correlation was found between all-cause mortality among people older than 80 years and the proportion of air samples containing NO2 in levels beyond its maximum permissible concentration. Predictive models allow us to calculate a positive effect of modifying environmental factors for reducing additional risk of population morbidity and mortality.

Selenium nanoparticles (Se NPs) have found wide application in many human economic activities. Therefore, it is necessary to predict and assess emerging potential health risks. Nanotoxicants can affect the body causing negative effects that have a non-linear dependence on the dose of a toxic substance. There is no consensus on the LD50 of Se NPs. Recent data on the dose-dependent liver response to different exposures of selenium nanoparticles are contradictory. The aim is to study and characterize potentially adverse dose-dependent effects in the liver under exposure to selenium oxide nanoparticles in a subchronic experiment using mathematical models. Exposure was modeled on male rats aged 3 to 4 months, 12 animals in each group. We used three levels of selenium nanoxide doses for subchronic exposure: 3.6, 18, and 36 mg/kg. The research was approved by the Local Ethics Committee of the Yekaterinburg Medical Research Center for Prophylaxis and Health Protection in Industrial Workers (Protocol No. 2 of April 20, 2021). We observed an atypical dose-response relationship between selenium nanooxide exposure and hepatic changes. The negative effects included pronounced changes in mitochondria of liver cells as well as an imbalance of blood enzymes and cellular composition of the liver, which may indicate damage to the organ and impaired secretory functions following the exposure to low and moderate concentrations of SeO nanoparticles. Our findings can be used for determining chemical safety standards for selenium oxide nanoparticles and assessing their health risks.

Socio-economic stability of any state is determined by the health of employable population, formed by an individual’s behavior, which can be aimed both at preserving health (self-preservation) and at its destruction (risky behavior). Based on literature analysis, three groups of factors have been identified that determine an individual's behavior in the field of health: socio-biological, socio-economic, and socio-psychological. These factors gave grounds for developing a mathematical model of multifactorial causation of self-preservation and risky behavior pursued by employable population living in an industrial megacity. The empirical base was formed by data from a formalized survey conducted in 2025 among residents of Perm city (n = 582). The data were analyzed using the SPSS Statistics software. The model was built using the neural network procedure of the multilayer perceptron (MLP). The study has found that health behavior of employable population living in Perm is characterized by a moderate risk profile. This is reflected in a moderate level of commitment to physical activity and medical practices, as well as relatively low manifestation of addictions. The factors identified in the study have a complex interrelationship. At the same time, there is a lack of an unambiguous link between health attitudes and actual implementation of consistent health-preserving behavior. Social support functions as a factor contributing to health preservation, but only with moderate intensity; its excessive manifestation can negate an individual's personal responsibility. In addition, influence of social connections has a bilateral effect: they can both provide support and contribute to formation of unhealthy behaviors through normative pressure. A high level of subjective security perception contributes to increased inclination for self-preservation behavior, while a decrease in this perception initiates the opposite process. The study highlights complex mechanisms of interaction between factors and self-preservation behavior pointing out that practices aimed at preserving health do not always manifest themselves in a systematic and sustainable form. The results substantiate the necessity to conduct investigative search for additional components forming the structure of self-preservation behavior in addition to behavioral practices. Preventive approaches to reducing risky behavior among employable population should take into account specific factors, which determine this behavior in various social groups, and adapt to their specific needs.

Increasing human-induced pollution of water objects, climate change, creation of reservoirs, and a decrease in water flow rates have accelerated saturation of water bodies with biogenic substances, which in turn has caused massive growth and spread of cyanobacteria. Intensification of “blooming” processes in water bodies is observed almost everywhere. In respect to human health hazards, the issue of massive growth of toxic cyanobacteria in surface water bodies used for drinking and recreational purposes is related to the possibility of various cyanotoxins forming in the water. This includes cylindrospermopsin (CYN), which is classified by the World Health Organization as a high-priority environmental pollutant, and this highlights high relevance of studying it. Assessing the experience gained by foreign researchers in studying the content of cyanobacteria in water bodies, it should be noted that there is a fairly wide species diversity of blue-green algae, depending on regional prevalence. In many countries across the globe, the list of substances for drinking water quality control has been expanded to include not only the content of cyanobacteria metabolic products, but also, in some cases, the content of their specific species composition. A number of studies by foreign and Russian researchers have shown the need for timely measures aimed at raising drinking water safety by regulating metabolic products of cyanobacteria. The aim of this study was to substantiate the maximum permissible concentration (MPC) of CYN content in water for household and drinking water use, as well as for recreational needs. The study included analysis of the results obtained by research on the physicochemical properties and toxicity of CYN, as well as a subchronic experiment to investigate general toxic effects and specific ones including neurotoxic, embryotoxic, and teratogenic effects upon conditions intragastric administration to animals. As a result, we established parameters of toxic effects produced by CYN and its hazard category and substantiated the MPC for the chemical in water equal to 1.0 µg/l, the sanitary-toxicological indicator of harm, and the hazard category.

Increased work requirements accompanied by a long period of continuous exposure are the most common predictors of burnout syndrome among healthcare workers. The great variability of Russian and foreign data on prevalence of burnout among healthcare workers indicates some unaccounted factors determining different levels of the studied phenomenon as well as unresolved evaluation and technological approaches to its early prevention within healthcare personnel management. The aim of the study was to create a model for predicting and managing the risks of occupational burnout among general practitioners. A survey was conducted among general practitioners (n = 340) employed at healthcare institutions in Moscow in the period from 2022 to 2023. The survey relied on using the Russian version of the international psychosocial questionnaire COPSOQ III (Long version) adapted for healthcare workers. Burnout levels in doctors with low job satisfaction were determined with reliability p ≤ 0.05 by the Kruskal – Wallis test. Prediction was calculated by using linear regression analysis; models of qualitative target variables were calculated using the Decision Tree method. Relative risks and odds ratio (95 % CI) were calculated as a quantitative measure of effects. Statistically significant differences per 38 psychosocial factors were confirmed at p < 0.0001. In a representative sample of doctors with low job satisfaction, those with the high level of burnout accounted for 1.72 %; ‘Norm’, 43.10 %; ‘Low’, 55.18 %. On the example of the Decision Tree model, the study described an algorithm for managing evaluation parameters of low job satisfaction, which was significant for managing risks of occupational burnout in general practitioners and depended on intra-organizational psychosocial factors ‘Uncertainty over Working Conditions’, ‘Work Life Conflicts’ and ‘Depressive symptoms’ and contributed to an increase up to 80 % or decrease down to 3.0 % depending on their impact in an occupational environment. The study findings substantiate the fact that an increase in medical and social effectiveness of healthcare workers can be based on employing developed organizational technologies for preventing critical levels of low job satisfaction and occupational burnout in general practitioners as well as declining quality of rendered healthcare services. The risk management algorithm offers to consider levels of job dissatisfaction, occupational burnout and the factors with the greatest influence of psychosocial working conditions and individual traits of general practitioners.