Maximum Permissible Concentration Research Articles

Endothelial dysfunction in combination of occupational pathology of the respiratory system and atherosclerosis in coal industry workers

Introduction. The increasing prevalence of cardiovascular pathology among industrial workers determines the importance of studying not only occupational diseases, but also their combination with diseases of the circulatory system. Endothelial dysfunction is a key link in the pathogenesis of atherosclerosis. Evaluation of endothelial function indicators in occupational respiratory diseases in combination with atherosclerosis in workers of the coal mining industry is an urgent task. The study aims to consider the indicators of endothelial function in miners with occupational respiratory diseases in combination with atherosclerosis. Materials and methods. The authors have examined 88 miners with previously diagnosed occupational respiratory diseases (chronic dust bronchitis, anthracosilicosis, chronic obstructive pulmonary disease), 45 of them showed signs of atherosclerosis. There were two comparison groups without signs of atherosclerosis: 44 miners who work long-term in harmful working conditions, without lung pathology (control group) and 42 residents of Novokuznetsk who have never worked in harmful working conditions, and without lung pathology (unexposed group). Results. We found that miners with occupational respiratory diseases in combination with atherosclerosis had several forms of endothelial dysfunction: vasomotor (decreased synthesis of nitric oxide, increased endothelin-1 levels), hemostatic (increased levels of Willebrand factor), adhesive (increased levels of endothelial adhesion molecules sVCAM-1). The development of respiratory insufficiency in miners with occupational respiratory diseases increases endothelial dysfunction: miners with respiratory insufficiency have lower levels of nitric oxide (NO), higher levels of endothelin-1 and endothelial adhesion molecules sVCAM-1 than miners without respiratory insufficiency. There are correlations between indicators of endothelial function and production factors: with work experience in harmful working conditions, the level of the average concentration of coal-rock dust in the workplace and the frequency of exceeding the maximum permissible concentration of coal-rock dust. Limitations. The study is limited to a sample of workers in the main professions of coal mines who were examined at the Research Institute of Complex Hygiene Problems and Occupational Diseases, aged 40 to 54 years, with more than 15 years of experience working in underground dust conditions. Conclusion. Miners with occupational respiratory diseases in combination with atherosclerosis develop several forms of endothelial dysfunction: vasomotor, hemostatic, adhesive. The development of respiratory failure increases endothelial dysfunction. Ethics. This medical study involving a human as a subject was carried out in compliance with the Ethical principles presented in the latest version of the Helsinki Declaration, developed by the World Medical Association.

Environmental monitoring of heavy metal content in the hydrographic network of a large city river

ABSTRACT Samples of edaphotopes were taken from a depth of 0–15 cm for analyses in this study. It was found that the water in the areas of the Hnidavske swamp and Teremnivski ponds was the most polluted. The level of Zn (0.01 mg/dm3) exceeded the maximum permissible concentration (MPC) at site 5 (Lypnyany village, outside the city of Lutsk, the content was 0.015 mg/dm3) and Hnidavske marsh (0.019 mg/dm3). At all study sites, Cr (0.001 mg/dm3) ranging from 0.002 to 0.005 mg/dm3, Co (0.005 mg/dm3) from 0.008 to 0.01 mg/dm3, and Ni (0.01 mg/dm3) from 0.02 to 0.036 mg/dm3 were also found to exceed the MPC. However, Cd levels (0.005 mg/dm3) did not exceed the MPC and was within the normal range at all study sites (0.0016–0.003 mg/dm3).

Polyaromatic hydrocarbons of small reservoirs of the Tomsk region

Relevance. The assessment of the state of natural waters includes the determination of a number of physico-chemical indicators, on the basis of which various indices and classifications are developed. However, they do not take into account a number of pollutants that have a significant impact on the state of the reservoir, for example, polyaromatic hydrocarbons. The article considers some aspects of determining priority pollutants, which include polyaromatic hydrocarbons, according to environmental hazard criteria: toxicity, carcinogenicity, prevalence, frequency of occurrence, source of origin (anthropogenic or natural). Hydrochemical parameters such as pH, dissolved oxygen content, biological oxygen consumption (BPK5), and ion content are taken into account to determine water quality. An attempt was made to assess the impact of polyaromatic hydrocarbons on the ecological state of water bodies and to take into account their contribution to changes in the values of the water pollution index. All these data prove the relevance of the study. Aim. To establish the composition of polyaromatic hydrocarbons in the surface waters of small reservoirs of the Tomsk region to assess anthropogenic load and to show the relationship with the indices of natural water quality. Methods. Extraction, liquid adsorption chromatography, high-performance liquid chromatography, capillary electrophoresis, amperometry, titrimetry. Results. Small lakes of the Tomsk region were studied for the content of 13 polyaromatic hydrocarbons. The authors have carried out the identification by high-performance liquid chromatography with fluorimetric detection. The total content of polyaromatic compounds in the studied surface water samples varies from 0.37 to 0.54 mcg/l. In the polyaromatic hydrocarbons mixture in aqueous samples, there is an increased content of light 2–3 nuclear polyarenes with better solubility (naphthalene, fluorene and phenanthrene), as well as benz[a]anthracene. The content of inorganic components represented by cations and anions does not exceed the maximum permissible concentrations. The water pollution index was calculated; all lakes are moderately polluted, closer to polluted. The paper demonstrates the dependence of the water pollution index coefficient on the content of high-molecular polyaromatic hydrocarbons and the ratio of high-molecular to low-molecular polyaromatic hydrocarbons. It is shown that the higher the value of the water pollution index coefficient, the higher the proportion of difficult-to-oxidize components in surface waters.

Response of oxidative stress and neurotoxicity biomarkers in rainbow trout (Oncorhynchus mykiss) after exposure to six-metal mixtures

ABSTRACT The activity of liver catalase and brain acetylcholinesterase was assessed in rainbow trout (Oncorhynchus mykiss) after 7- and 14-day exposure to a six-metal mixture at the maximum permissible concentrations accepted for inland waters in the EU (2013/39/EU; 2008/105/EC) (Zn − 0.1, Ni − 0.034, Cu − 0.01, Cr − 0.01, Cd − 0.0015 and Pb − 0.014 mg L−1) and to the same six-metal mixtures with tenfold reduced concentration of Cu and Cr ions. A statistically significant increase of up to 26% of catalase and 52% of acetylcholinesterase activity was observed in rainbow trout after 7 days of exposure to the six-metal mixture at the maximum permissible concentrations in comparison to a control group. After 14-day treatment, neither CAT nor AChE showed significant response to all tested metal mixtures. The six-metal mixture with the tenfold reduced concentration of Cr increased brain AChE activity in O. mykiss after 7 days of exposure (35%). Enhancement of catalase activity caused by the mixture of the six metals at the maximum permissible concentrations and the increased acetylcholinesterase activity in response to the same metal mixture and mixture with tenfold reduced Cr concentration after 7 days of exposure indicates the induction of oxidative stress and disturbance of cholinergic system homeostasis respectively.

Scientific substantiation of the maximum permissible concentration of the pharmaceutical substance osimertinib mesylate in the air of the working area

Introduction. Osimertinib, a 3rd generation epidermal growth factor receptor tyrosine kinase inhibitor, is currently the only drug registered for the treatment of metastatic non-small cell lung cancer in patients with a positive T790M mutation status. The production of osimertinib mesylate is planned on the territory of the Russian Federation, which necessitates research to substantiate the hygienic standard for the aerosol content of the substance in the air of the working area. Conducting research to substantiate the maximum permissible concentration of a substance requires significant material and time resources, while using the results of preclinical and clinical studies, mathematical modeling of processes, and risk assessment methodology allows for a comprehensive assessment of the substance, while significantly reducing the time and cost of work. The study aims to scientifically substantiate the maximum permissible concentration of the pharmaceutical substance osimertinib mesylate in the air of the working area using data from toxicological studies and mathematical modeling of the effects of the substance on humans in industrial conditions. Materials and methods. The materials used were domestic and international databases, reports, research protocols, scientific articles and monographs containing information on the physico-chemical and toxic properties, pharmacotherapeutic activity of osimertinib. Results. The specialists have conducted hygienic regulation of osimertinib, taking into account data on its toxicity, danger, pharmacotherapeutic activity, side effects, long-term consequences, pharmacokinetic studies and modeling. To substantiate the value of the maximum permissible concentration, the authors used the reference points: an inactive NOEL level of 1 mg/­kg/­day for general toxic effect, established in a 92-day experiment on rats with intragastric administration; the lowest observed level of adverse effects of LOAEL is 0.5 mg/kg/day for general toxic effect, established in a 180-day experiment on dogs with intragastric administration; the level that does not cause adverse effects of NOAEL is 10 mg/kg/day for general toxic effect, established in a 180-day experiment on mice with intragastric administration. Safe concentrations of osimertinib in the air of the work area were evaluated using reference points, including the pharmacological effect and the minimum daily therapeutic dose; toxicokinetic modeling of concentrations of a substance in the human body under production conditions and the level of minimal risk. Limitation. The study is limited to the review of open literature sources describing the toxicological/toxicokinetic characteristics of osimertinib mesylate. Conclusion. The most stringent indicators of safe exposure levels, established on the basis of pharmacological effect and toxicokinetic modeling in dogs, allowed us to recommend 0.005 mg/m3, aerosol, hazard class 1 as the maximum permissible concentration in the air of the working area for osimertinib mesylate. Ethics. This study did not require the conclusion of the Ethics Committee.

Assessment of the public health risk caused by exposure to atmospheric emissions from an aluminum plant

Introduction. Aluminum production is accompanied by emissions of pollutants that can negatively affect the environment and public health. The study aims to determine the impact of atmospheric emissions from an aluminum plant on the health of the population of the city of Novokuznetsk based on a risk assessment. Materials and methods. The volume of maximum permissible emissions of the Novokuznetsk Aluminum Plant was used in the work. Experts calculated the maximum and average concentrations of substances at 40 exposure points. The maximum permissible concentrations of substances were determined in accordance with SanPiN 1.2.3685-21. The authors calculated the carcinogenic risk and the risk of non-carcinogenic effects in accordance with the Guidelines 2.1.10.1920-04. They carried out the classification of risk levels based on methodological recommendations 2.1.10.0156-19. 2.1.10. Results. The authors have selected pollutants were for risk assessment: inorganic dust with a SiO2 content of <20%, sulfur dioxide, benz(a)pyrene, hydrogen fluoride, carbon monoxide, nitrogen dioxide, suspended solids, nitrogen oxide, carbon (soot). The maximum concentrations were 0.1–3.77 MPC for inorganic dust (SiO2<20%), 0.1–2.64 MPC for hydrogen fluoride and 0.05–1.74 MPC for sulfur dioxide; average concentrations were up to 9.16 MPC for benz(a)pyrene. The hazard indices for acute exposure are at an acceptable level; For chronic exposures, they correspond to alarming and high levels, reaching the highest value (13.469) at a point located closer to the sources of emissions. Hazard indices for critical organs and systems in acute exposures are at acceptable or minimum (target) levels, in chronic exposures they correspond to alarming and high-risk levels. The respiratory and immune systems are most affected. The total individual carcinogenic risk ranges from 4×10–7 to 8×10–6, without exceeding the upper limit of the permissible risk. Residents of the Kuznetsk district of the city are most affected by emissions. Limitations. The main limitation in the work carried out was the use of calculated concentrations of pollutants for risk assessment without the use of in-kind indicators. Conclusion. Elevated concentrations of pollutants were detected in the atmospheric air of residential areas adjacent to the territory of the aluminum plant, which determine alarming and high levels of non-carcinogenic risk to public health. Ethics. This study did not require the conclusion of the Ethics Committee.

Assessment of the risk to the health of the population living in the zone influenced by atmospheric emissions from the engineering industry

Introduction. During operation, machine-building enterprises emit pollutants that can negatively affect the health of the population. The study aims to determine the impact of emissions from a machine–building plant, as well as background atmospheric pollution, on the health risk of the population of Novokuznetsk. Materials and methods. The work used data from the volume of maximum permissible emissions of a machine-building plant. The researchers calculated the maximum and average concentrations of pollutants using the "ECOcenter – Standard" program at 36 exposure points selected on the city map. Experts determined the maximum permissible concentrations of pollutants in the atmosphere in accordance with SanPiN 1.2.3685-21. The authors calculated the risks to public health in accordance with the Guidelines R 2.1.10.1920-04. The classification of risk levels was carried out on the basis of MP 2.1.10.0156-19. 2.1.10. Scientists also made a risk assessment considering background atmospheric pollution. Results. Specialists carried out a risk assessment from exposure to nitrogen dioxide, carbon monoxide, sulfur dioxide, carbon (soot), inorganic dust, hexavalent chromium. The maximum and average concentrations of pollutants, as well as the maximum concentrations calculated taking into account background pollution, did not exceed the maximum permissible level. The average concentrations of nitrogen dioxide and hexavalent chromium, taking into account the background, exceeded the hygienic standard. The values of the hazard indices for acute and chronic exposures without taking into account the background, as well as for acute exposures taking into account the background, corresponded to the minimum (target) risk level. The values of the hazard indices for chronic inhalation effects, considering the background, corresponded to the alarming risk level at five points, amounting to 3.084–3.800. With chronic exposure, taking into account the background, an alarming level of risk was revealed for the effect on the respiratory organs (at four points the hazard index was 3.117 to 3.616) and blood (at three points the hazard index was in the range from 3.090 to 3.433). The total individual carcinogenic risk, excluding background, did not exceed the permissible level, ranging from 1.08×10–8 to 2.43×10–7 at different points, taking into account the background, amounted to 1.79×10–4–2.26×10–4, which corresponds to an alarming level. Hexavalent chromium makes the main contribution to the formation of carcinogenic risk. Limitations. Calculated concentrations of pollutants were used to assess the risks. Conclusion. The risks from exposure to atmospheric emissions from the machine-building plant correspond to the minimum (target) level. Background concentrations of toxic substances in chronic inhalation exposures determine an alarming level of non-carcinogenic risk at five points, as well as an alarming level of carcinogenic risk at all points of exposure. Ethics. This study did not require the conclusion of the Ethics Committee.

Geoecological Assessment of Fluorine Contamination of Environmental Components in the Zone of Influence of an Abandoned Rare-metal Mine in the Murmansk Region

A geoecological assessment of fluorine contamination of environmental components in the zone of influence of an abandoned rare-metal mine in the Murmansk region was carried out. Samples were taken of loparite ore enrichment tailings, soils around the tailings pond and the Loparitovy, Alluaiv, Azimut creeks and the watercourse flowing through the mine after the mining impact. The content of water-soluble fluorine in the collected samples was determined. No exceedance of maximum permissible concentration (MPC) of fluorides in soil was found. Increased content of fluoride ions (up to 15 MPC) in water samples from the watercourse was recorded. It is concluded that the production facility closed more than 15 years ago has a negative impact on ecosystems.

Assessment and condition of a small river in urbanized areas (with the example of the river Kurdyum of the municipal formation “Saratov city”)

The results of the study of the ecological status of the Kurdyum river within the municipal formation “Saratov city” are presented. The hydrochemical regime, hydrophilic flora and vegetation of the watercourse were studied in the 2022–2023 field seasons. The ecological status of the river by structural parameters of macrophytes was assessed. The species composition of aquatic plants in the river Kurdyum was represented by 41 macrophyte species belonging to 32 genera, 23 families and three divisions (Charophyta, Polypodiophyta, and Magnoliophyta). The families Potamogetonaceae, Asteraceae, Poaceae, Typhaceae and Ranunculaceae predominated by the number of species. The genus Potamogeton contained the greatest number of species (four) while other genera were represented by one – two species. Hydrophytes were a numerous ecological group, accounting for 51% of the total number of species. New locations of species rare for the Saratov region (Myriophyllum verticillatum and Zannichellia palustris) were revealed. The vegetation cover of the Kurdyum river is characterized by the greatest phytocenotic diversity of true aquatic vegetation. The impoverishment of the phytocenotic composition of helophytic and hygrophytic vegetation is explained by the lack of favorable conditions for the development of their phytocenoses (the watercourse has abrasion banks along a significant length) or trampling and eating by grazing animals. The studied river is characterized by species diversity in comparison with previously studied urban watercourses. Index comparison has revealed an inverse relationship between species diversity and the level of anthropogenic load. Cluster analysis has revealed that the structure of flora and vegetation from the source to the mouth of the river is not homogeneous and is formed under the influence of a combination of hydrological, chemical and anthropogenic factors. The results of our chemical analysis of the water showed that the maximum permissible concentrations of Fe, Zn, Cu, surfactants, NO2 and NH3 were exceeded throughout the river. However, the environmental indicators assessed based on the structural parameters of macrophytes allow us to consider the ecological status of the watercourse satisfactory. Thus, the Kurdyum river is moderately polluted with a high trophic status.

Speciation of cadmium in river waters at different contents (model experiment results)

The data of cadmium forms with a possible increase in technogenic load are presented. The experiments carried out made it possible to simulate the features of the redistribution of chemical forms of cadmium in river waters when it enters in concentrations exceeding the maximum permissible concentrations (MPC). It has been shown that most of the introduced cadmium can pass from dissolved to suspended form, thereby promoting the deposition of suspended particles to the bottom at low flow rates.

A comparative study between the efficacy of fertigation and spraying procedures in terms of the content of Cadmium (Cd) and Arsenic (As) in greenhouse cucumber.

A comparative study between fertigation and spraying procedures in terms of the status of Cadmium (Cd) and Arsenic (As) in greenhouse cucumber was conducted as a two-factor split plot based on a randomized complete block design with three replications at the Soil and Water Research Institute, Karaj, Iran in 2023. The main and sub-factors were respectively fertigation and spraying that were used in two levels [the maximum permissible concentration of Cd and As in granular triple super phosphate fertilizer (25ppm Cd and 50ppm As) and the minimum permissible concentration of these metals in granular triple super phosphate fertilizer (5ppm Cd and 5ppm As)]. Spraying was done in three modes (spraying of leaves, leaves and fruit, and fruit). On average, the results showed that the order of the concentration of Cd in plant tissues (DW) was as leaf (0.284mg/kg) > fruit peel (0.102mg/kg) > fruit peel + flesh (0.054mg/kg) > fruit flesh (0.044mg/kg). This order for As was as leaf (0.608mg/kg) > fruit flesh (0.127mg/kg) > fruit peel + flesh (0.109mg/kg) > fruit peel (0.072mg/kg). Based on the measurements, the spraying procedure accumulated more amounts of Cd and As in the fruit (i.e., peel + flesh) than the fertigation procedure. In general, it is concluded that under soilless culture, the status of heavy metals in plant tissues of greenhouse cucumber is related to the nature of the metal, the organ exposed to the metal, and the fertilization procedure. Because there is the risk of contamination of vegetables grown in the areas fertigated and sprayed with poor-quality nutrient solutions in terms of the content of heavy metals, the frequency of fertigation and spraying needs to be monitored continuously for the quality of the vegetables cultivated in greenhouses.

Внутригодовая динамика химического состава воды в устье реки Баксан

The article presents the results of a study of the intra-annual dynamics of the chemical composition of water at the mouth of the Baksan River in 2023. The intra-annual dynamics of transparency, pH, mineralization, hardness, permanganate oxidizability, content of macrocomponents (bicarbonates, chlorides, sulfates, nitrites, nitrates) and iron compounds were studied. According to average annual values, the water of the studied object has average hardness and belongs to the hydrocarbonate, fresh waters of rivers of average mineralization. An excess of the maximum permissible concentration for sulfates, nitrates and iron compounds was detected. It is shown that the hydrochemical regime of the studied water body is interconnected with level and thermal regimes and is influenced by anthropogenic factors. The data obtained are necessary to identify patterns of distribution of substances in natural geosystems located in the Malka River basin, of which the Baksan River is a first-order tributary.

Cloud point extraction and characterization of zinc oxide nanoparticles isolated from infant milk formulas

The increasing presence of nanoparticles in food products, especially in those consumed by sensitive populations like infants, raises justified health concerns. The presence of zinc oxide nanoparticles (ZnO-NPs) in three different commercial infant milk formulas were analyzed. In addition, one maternal food supplement was included in this study. Notably, existing regulations lack specificity regarding the size distribution of nanoparticles (NPs) and the maximum permissible concentrations in commercial infant products. Except in one sample, the total zinc content exceeded the reported amount in the nutritional label, which varied from 34 to 119 µg/g. This work validated the cloud point extraction (CPE) technique for the effective isolation of ZnO-NPs from the selected products. CPE was then used to evaluate the ZnO-NPs concentrations in commercially available infant formulas and maternal supplements. Using inductively coupled plasma optical emission spectrometry (ICP-OES), the ZnO-NPs and total Zn concentrations were determined. The ZnO-NPs concentration ranged from 16 to 39 µg/g, representing a considerable portion of the total zinc content. Transmission electron microscopy (TEM) analysis indicated the presence of nanoparticles with an average diameter of 6.3 nm. The NPs size could determine their cell internalization, and thus, the potential cytotoxic effects are discussed. These findings underscore the need for rigorous isolation and quantification of nanoparticles from infant milk formulas, and as an inevitable first step for in vitro and in vivo toxicity studies to address the potential health impact of nanoparticles in food products.

Oil pollution near the ports of Aktau, Kuryk and Ersai (the Caspian Sea): Satellite and in-situ data

To study oil pollution on the surface of the Caspian Sea in the area of the ports of Aktau, Kuryk and Ersai, the archives of radar data obtained from the synthetic aperture radars of the Sentinel-1 satellite constellation belonging to the European Space Agency for the period 2013 - 2022 were selected. For this purpose, a specialized satellite information service “See the Caspian Sea” (STCS) (http://caspian.geosmis.ru) created in 2023 jointly by Space Research Institute and Shirshov Institute of Oceanology of Russian Academy of Sciences was used. This system is specifically designed for the Caspian Sea and is created on the basis of the existing “See the Sea” (STS) service, which is part of the “IKI-Monitoring” Center for Collective Use established in Space Research Institute. For a given polygon in the region of the ports of Aktau, Kuryk and Ersai, in the STCS system, time series archives consisting of more than 3,700 radar images were examined. Each image was manually analyzed to identify dark areas of reduced radar signal that could be identified as oil contamination. A total of 15 oil slicks were discovered, up to 89 km in length and up to 8 km2 in area. A satellite image of each oil slick is presented in the article, as well as its main characteristics. In addition, as part of the project “Satellite monitoring of the water areas of the ports of Aktau and Kuryk”, sea water samples were taken in the area of the ports of Aktau and Kuryk, which showed the content of oil products in the range of 0.014-0.1 mg/dm3. Thus, the resulting concentrations turned out to be less than the maximum permissible concentration of 0.1 mg per liter.

Chronic and Periodic Effects of Smoke from Crop Residue Combustion on Soil Enzymatic Activity

Wildfires lead to the emission of large volumes of toxic smoke, which is transported hundreds of kilometres away from the fires and can have a negative impact on soil, biota and humans. A series of modelling experiments on pyrogenic fumigation of soil were carried out to assess the effects of gaseous products from wildfires on soil biochemical parameters. The effects of chronic exposure to gaseous substances and periodic, repetitive effects of smoke exposure on soil were determined. The results were compared with a single intensive smoke exposure. It was found that pyrogenic impact significantly affected the change of enzymatic activity of ordinary chernozem. The degree of influence depended on the duration and periodicity of smoke exposure. In all experiments enzymes of oxidoreductase class (catalase, peroxidase, polyphenol oxidase) were more sensitive to fumigation than invertase from hydrolase class. The reason of suppression of enzymatic activity of soils is high concentrations of toxic gases. The following concentrations exceeded the maximum permissible concentrations for atmospheric air: CO 714 times, phenol (hydroxybenzene) 441 times, acetaldehyde 24100 times, formaldehyde 190 times. Accumulation of polycyclic aromatic hydrocarbons (PAHs) in soil after fumigation was revealed, the total content of PAHs was 377 ng/g. The highest values were recorded for naphthalene, where the concentration was 4.4 times higher than the maximum permissible and phenanthrene 2.8 times higher than the maximum permissible. It was found that 60-minute intensive smoke affects the soil to a lesser extent than chronic and periodic. Indicators of enzymatic activity of chernozem after such fumigation decreased by 15-33% depending on the enzyme, in chronic and periodic by 41-84 and 31-78%, respectively. The obtained data indicate a significant effect of smoke on enzymatic activity of soils under chronic and periodic exposure to gaseous products of combustion.

Sanitary and Chemical Analysis of Drinking Water and Laboratory Control of the Content of Toxic Elements of Pesticides and Mycotoxins in Food Products

Relevance of the study: nutrition is the most important factor in maintaining health, normal growth and development of children and adolescents, preventing a number of diseases, maintaining high performance of the adult population, maintaining active longevity. Drinking water and food are necessary for the existence of humans and all life on Earth. Issues related to increasing responsibility for the effectiveness and objectivity of quality control of drinking water and food products are relevant in guaranteeing their safety for the health of consumers. Objectives of the study: to study the quality of drinking water and the efficiency of the water supply system in Osh in the period from 2020 to 2023; analysis of compliance of drinking water quality with sanitary and chemical standards; development of recommendations for improving the quality of water and the water supply system in Osh. Determination of toxic elements, pesticides and mycotoxins in food products, determination of physicochemical indicators and toxic elements in drinking water, pesticides and mycotoxins in food products was carried out in accordance with regulatory documents of GOST and the maximum permissible concentration. The test results showed the normal and permissible levels of pH, total iron, fluorides, hardness, dry residue, ammonia, nitrates, etc. in water, and the content of aflatoxin B1, the mass concentration of cadmium and lead, hexachlorane, dichlorodiphenyltrichloroethane in food products. For a more in-depth analysis, it is recommended to use additional data on climatic conditions, geological features of the region, as well as the demographic situation in Osh.

Radiological monitoring and assessment of the radiation situation in the Kungur Ice Cave

This article presents the results of comprehensive radiological studies conducted in 2021 in order to assess the radiation situation in the Kungur Ice Cave (hereinafter referred to as the KIC). Since the cave is a fairly popular sightseeing object, therefore, the safety of both tourists and workers is a key task for scientific study. The radiation safety assessment was carried out taking into account the parameters of the radiation (gamma) background, measurements of radon and thoron concentrations, microclimatic indicators (air temperature, humidity), airflow rate, illumination and calculation of the indicator of a special assessment of working conditions (SAWC). Such comprehensive and detailed studies were conducted in the KIC for the first time, allowing some patterns to be identified and confirmed. For the indicators of gamma-activity and radon concentration, there is a clear dependence on the season of the year, which is directly related to microclimatic indicators, as well as to compliance with the ventilation regulations that have been established in the cave. The applied ventilation modes provide safe values of the radiation background and toron. In the summer months, the average radon content in the cave exceeds the maximum permissible concentrations by a factor of 7, which required calculation of the time of work in the cave. For the first time, special assessment of working conditions has been calculated for Kungur Ice Cave, but only for the winter period. The SAWC is defined for a working group consisting of engineers, workers and guides, taking into account such parameters as temperature, illumination, humidity, severity and intensity of labor and ionizing radiation (radiation background). According to preliminary data, the overall assessment of labor based on all parameters falls under the “harmful” class of conditions.

PREVENTION OF TECHNOLOGICAL EMERGENCIES IN THE WARFARE ZONE

In a war zone, there are potential risks of the spread of an emergency due to harmful (polluting) substances in the environment above the maximum permissible concentrations. The causes of the danger are explosions, detonations, chemical spills, military vehicles, shelling or destruction of the infrastructure of oil facilities, and damage to the infrastructure of water supply and drainage. Method of preventing emergencies of a technological nature includes procedures using modern technologies and information systems to ensure timely response and minimise risks for the population and the environment. The algorithm for implementing the method of technological emergency prevention due to harmful (polluting) substances in the atmospheric air above the maximum permissible concentration in the combat zone consists of procedures. Procedures include work on planning and preparation, measurement and data collection, data analysis and processing, management decision-making, and control. Using a laser complex to prevent emergencies is an innovative approach that helps to identify potential threats and control their development accurately and effectively. The laser complex solves the dual task of detecting and immediately evaluating polluting gases and aerosols. The article also describes the algorithm for preventing technological emergencies due to harmful (polluting) substances in drinking water above the maximum permissible concentration in the combat zone. Groundwater is the predominant object of danger. The procedures consist of collecting and analysing statistical data, deciding the priority of monitoring areas, determining goals by types of hazards, setting tasks, choosing a monitoring scheme, determining monitoring procedures and their characteristics, solving monitoring issues, monitoring, making management decisions to limit the spread of the consequences of hazards. Effective emergency prevention procedures planned and carried out using modern tools and instruments can contain the spread of the consequences of a technological emergency, limiting the number of victims and injured and the area of hazard spread. Keywords: soil, air, monitoring, laser complex, emergency.

Changes in the Chemical Composition and Antimicrobial Activity of Linden, Buckwheat and Sunflower Honey Stored at Low Temperatures

Natural bee honey can change its physicochemical and biological properties during storage. Literature data on long-term storage of honey at low temperatures (from 0 to -20 °C) indicate that this ensures the stability of some physicochemical parameters. Despite the potential benefits of these temperature regimes for practical use, it is important to consider their potential negative effects on honey quality. The aim of this study was to investigate the influence of various temperature conditions on the physicochemical and biochemical parameters of linden, buckwheat, and sunflower honeys during storage for 12 months. For the first time, a wide range of physicochemical parameters of honey samples was analyzed before and during storage for 12 months at temperatures of 18, 10, 5, 0, -5, -10 and -18 (±2) °C. The evaluation of the physicochemical parameters before storage demonstrated that the samples fully complied with the Interstate Standards. Throughout the storage period, the HMF level remained stable at -18 °C, whereas it significantly increased at higher temperatures; for example, after 12 months at 18 °C, the increase ranged from 472.5% to 488.1%, depending on the botanical origin of the honey. However, maximum permissible concentration – MPC (25 mg/kg) was not exceeded. A decrease in the activity of diastase, D-glucose-1-oxidase and catalase was observed at all temperature conditions already during the first month of storage. Minimal changes were observed at 0 and 5 °C. Hydrogen peroxide (H2O2) remained stable in this temperature range. Moisture content, total mass fraction of reducing sugars, and acidity did not change significantly in all samples. An antimicrobial study using test cultures found that honey stored at 5 and 0 °C had the greatest inhibitory effect. The data obtained demonstrates that the optimal temperature range for 12-month storage of honey is between 5 and 0 °C. These findings can be used as supplementary guidance when making amendments to regulatory documents governing storage requirements for this product.

Spraying or fertigation? looking for the better method in terms of the lower concentration of Pb and Ni in greenhouse cucumber.

This study was conducted to investigate the status of Lead (Pb) and Nickel (Ni) in greenhouse cucumber affected by fertigation and spraying as a factorial split plot arrangement based on a randomized complete block design (RCBD) with three replications at Soil and Water Research Institute, Karaj, Iran in 2023. The main and sub-plots were respectively fertigation and spraying that was applied in two levels [the minimum permissible concentration of these metals in granular triple super phosphate fertilizer (five ppm Pb and five ppm Ni) as the control treatment, and the maximum permissible concentration of Pb and Ni in granular triple super phosphate fertilizer (50 ppm Pb and 100 ppm Ni)]. Spraying was done in three modes (spraying leaves, leaves + fruit, and fruit). Based on the results, the highest concentration of Pb in the fruit (fruit peel + fruit flesh) (0.295 mg/kg DW) was recorded in the fertigation + spraying with the maximum permissible concentrations of Pb and Ni treatments. A general comparison between the two fertilization methods showed that the sprayingmethod accumulated a higher concentration of Pb in the fruit (i.e., peel + flesh) than the fertigation method. The reverse of this status happened for Ni, so the fertigation method accumulated a higher concentration of Ni in the fruit (skin + flesh) compared to the spraying method. On average, the order of Pb concentration in different organs was as follows: leaf (0.765mg/kg) > fruit peel (0.232mg/kg) > fruit peel + flesh (0.174mg/kg) > fruit flesh (0.129mg/kg). This order for Ni was as follows: fruit flesh (0.597mg/kg) > fruit peel + flesh (0.345mg/kg) > leaf (0.3mg/kg) > fruit peel (0.175mg/kg). These orders show that the status of the heavy metals in plant tissues is related to the nature of the metal, the type of the organ, and the method of fertilization.