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Introduction. Recently, there have been increasing changes in the technology of preparation of cement mixtures and concrete, the use of new components in their composition, since traditional materials are not quite suitable for the construction of hydraulic structures, including the internal coating of pipes and drinking water tanks. However, in addition to improving the characteristics of cement mixtures, additives can have a negative impact on the environment and human health by leaching out of cement into drinking water. The definition of only the main components specified in the “Universal sanitary-epidemiological and hygienic requirements for goods subject to sanitary-epidemiological supervision (control)” (hereinafter - the Universal Requirements) does not provide complete information about the chemical safety of cement materials during the hygienic assessment. Materials and methods. There were studied eleven samples of cement mixtures from various manufacturers repaired of reinforced concrete products and structures of general and special purpose, including those in contact with drinking water, and used for the sanitation of the internal surfaces of steel pipelines (including hot water supply systems) and repair and restoration work. The evaluation of samples was carried out taking into account Universal requirements, and indicators that are not mandatory for the evaluation of these materials were investigated. Results. Hygienic assessment of cement mixtures showed lithium to be detected in some extracts in concentrations from 20 mg/L to 0.18 mg/L, which is 666 times higher than its maximum permissible concentration - 0.03 mg/L. Also, two samples showed a slight excess of the permissible chromium concentration - 0.065 mg/L and 0.09 mg/L (MPC < 0.05). Iron and zinc in insignificant concentrations were found in aqueous extracts; in one of the samples a 2-fold excess of the manganese concentration was observed. One water extract contains silicates at a concentration of 34.24 mg/L, which exceeds their permissible levels in drinking water. The analysis also identified a number of organic compounds related to oxygen-containing compounds (alcohols, phenol derivatives, ketones, esters, phthalates), for most of which no MPC has been established. Limitations. The study was carried out on eleven samples of cement mixtures under standard conditions: infusion in model media for 30 days at room temperature in the ratio: 1 cm2 of the sample surface to 1 cm3 of water. Sampling was carried out on the Days 1, 3, 5, 10, 20 and 30 of research, without changing the test water. It is necessary to conduct similar studies under experimental conditions close to the operating conditions of these materials. Conclusion. Assessing the efficiency of migration from cement-bound materials, it is necessary to take into account their capillary-porous structure on the one hand and the ability to improve the coating properties over time by converting calcium hydroxide present in freshly applied cladding into denser calcium bicarbonate. The migration of chemicals from cement-bound material is to be evaluated by taking into account the specific conditions of their use in the practice of drinking water supply, and the assessment of the additives introduced should be carried out on test cement samples, since it is impossible to theoretically calculate the migration rate of the components from the finished material.

Introduction. Considerable attention is paid to the assessment of acute toxicity of chemical compounds during oral administration due to the different rates of absorption of substances in different animal species and various experimental conditions. Given the pace of development of the chemical industry, researchers are faced with the question of accelerating the study of the properties of substances and filling data gaps. Therefore, quantitative prediction of the toxic properties of substances using mathematical models based on the structure or structural properties of compounds - quantitative structure -activity relationship (QSAR) modeling - is one of the promising areas. The purpose of this study is to create and compare the performance of the obtained mathematical models for predicting the acute toxicity of various classes of chemicals. Materials and methods. The study included four classes of pesticides (organochlorine compounds (OCs), azoles, carbamates, organophosphorus compounds (OPs) in the amount of 100 compounds with descriptors calculated by PaDEL-Descriptors software ver. 2.21. Regression models were constructed in the WEKA software, subjected to an internal validation procedure. Statistical parameters such as the mean square error (RMSE) and the coefficient of determination (r 2) were used to assess the quality of regression models. Results. To predict acute oral toxicity of OCs and OPs, it is optimal to use a model in which neural networks and the support vector method are combined, for carbamates - an ensemble model that includes linear regression and the support vector method. For substances from the azole group, it was not possible to create a model that would meet the necessary requirements: r 2>0.6 for the training set and r 2 >0.5 for cross-validation. Limitations. The study is limited by the number of compounds studied, the class of chemical compounds, and the area of distribution of the results obtained during modeling. Conclusion. In this study, ensemble modelling methods demonstrated the best results in predicting acute oral toxicity for OCs, carbamates, and OPs.

The work is devoted to the study of the formation of bottom sediments and silt, their impact on the state of aquatic ecosystems, effective research methods and their practical application. Due to the continuous anthropogenic load, heavy metals, polycyclic aromatic hydrocarbons and other pollutants constantly accumulate in the silt and bottom formations. They undergo various chemical processes that can produce compounds that are even more toxic. The accumulation of this complex of pollutants subsequently becomes a source of secondary pollution, affecting the quality of water in reservoirs, reducing the species diversity of aquatic organisms and, through migration and movement along food chains, negatively affecting the condition of plants, animals and people, ultimately violating the processes of self-purification. Silt and bottom sediments thus become indicators of water pollution. On secondary deposits, biological processes are inhibited, anaerobic conditions arise, acidity increases, which contributes to the constant release and entry of harmful gases into the atmosphere. One of the main consequences of this process is the greenhouse effect and the violation of the heat balance. One of the ways to monitor bottom sediments is bio testing. In this method, crustaceans are chosen as test organisms because of their sensitivity to pollution, wide distribution. Bio testing can be used as an independent method for assessing the state of aquatic ecosystems, and in their integral assessment. Now in Russia there is no system for assessing the quality of bottom sediments, which greatly complicates the assessment of the state of surface water bodies and the prediction of negative processes. Thus, data on the composition of pollutants in silt and bottom sediments are not applicable for ecological characterization. Therefore, it seems necessary to create a unified methodology and establish interdepartmental communication of specialists in order to fully assess the pollution of water bodies and respond in time to threatening levels.

Introduction. The main reason for the problems of surface reservoirs in many regions of Russia is the non-compliance with sanitary protection zones and the discharge of insufficiently treated wastewater into reservoirs. SanPiN 1.2.3685-21 introduced a list of the new controlled sanitary-microbiological and parasitological safety indicators for disinfected wastewater and surface water bodies. For some indicators, there are no methods of determination in the current methodological documents. In this work, studies were carried out using various methods, including accelerated ones, which make it possible to determine the normalized indicators in wastewater and surface waters. Goals and objectives - optimization of methods for the study of surface and wastewater in the implementation of sanitary-microbiological and sanitary-parasitological control. Materials and methods. Bacteriological, parasitological indicators, as well as coliphages were determined in samples of surface and wastewater. To detect and identify generalized coliform bacteria, E. coli, enterococci, P. aeruginosa and legionella, in addition to membrane filtration and direct seeding methods, test systems (IDEXX) were used: Colilert-18 and Colilert-24, Pseudolert, Enterolert, Legionelert. Obligate anaerobes of C. perfringens were cultured in an anaerobic box (Anaerobic Station A55, Don Whitley Scientific) in an atmosphere of a three-component gas mixture. Species identification of microorganisms was carried out by time-of-flight mass spectrometry (MALDI TOF MS) using a Microflex mass spectrometer with MALDI BioTyper software (Bruker, Germany). Isolation of RNA/DNA of viruses and bacteria was carried out using a set of reagents “AmpliSens. RIBOT-prep.” Results. As a result of the conducted studies, P. aeruginosa; E. coli, R. ornithinolytica, A. hydrophila, A. caviae, A. molluscorum; E. hirae, E. faecium, E.faecalis; C. perfringens; S. lutetiensis, S. suis were isolated and identified from wastewater at all stages of treatment, high fungal contamination was found, and also Group F adenovirus DNA (both in wastewater and surface water samples) and additionally rotovirus and norovirus RNA, Campylobacter DNA. SarsCov-2 virus RNA was not detected in any sample. Lamblia spp., Blastocystis spp. and Cryptosporidium parvum were identified; opportunistic Entamoeba spp.; helminth eggs - Toxocara spp., Hymenolepis diminuta, Hymenolepis nana, Asagis lumbricoides, egg oncospheres Tenia spp.; Nematodes spp. larvae. Limitations. Since clinically significant strains of bacteria, fungi, and parasitic protozoa were found in the studied water samples, it is important to expand knowledge about water sources as reservoirs and spreaders of these pathogens. Conclusion. Monitoring is now urgently needed to quantify pathogens circulating in surface water and wastewater.

Introduction. For many years, two-component polyurethane coatings have been used as suitable systems for the protection and reconstruction of pipes in the practice of domestic drinking water supply. However, polyurethane can be a source of pollutants entering drinking water. Special attention in the hygienic assessment is paid to the main components of plastic, the released solvents and film-forming agents used in the formulation of the material. However, the definition of only priority components (taking into account Uniform sanitary requirements) does not provide complete information about the chemical stability of polymer materials during the hygienic assessment. Materials and methods. Eight different two-component polyurethane coatings of various manufacturers and manufacturers offered for use in drinking water supply are investigated in the work. The evaluation of these samples was carried out taking into account Uniform requirements (2010). Indicators that are not mandatory for the evaluation of polymer materials used in drinking water supply were also investigated. Results. Conducting a hygienic assessment of two-component polyurethane coatings shows fundamentally different chemicals to migrate into the model environment even from materials with the same type of components. When analyzing water extracts, from 9 to 40 organic compounds were identified at different temperatures. Most of them do not have the maximum permissible levels of their content in drinking water and there are no fully conducted toxicological studies of these chemicals to assess their safety for humans. There also were found three samples, from which inorganic components of cadmium and nickel migrated into distilled water above their maximum permissible values. Limitations. This study was conducted on the example of polyurethane coatings, as a particular example of the use of polymer materials in drinking water supply. It is necessary to conduct similar studies on other groups of polymers. Conclusion. At the moment, there are certain contradictions in the methodology and approaches to assessing the migration of chemicals from polymer coatings to drinking water. Therefore, their refinement and standardization is relevant, taking into account the increasing share of the use of polymer materials in human life.

The article discusses a functional-ecological approach to the selection of soils for the purpose of hygienic regulation of chemicals. The functional-ecological approach used to substantiate the choice of soil types in standardization is associated with the analysis of their main, variable functional characteristics including humus state, particle size distribution, oxidizing capacity, sorption capacity, cation exchange capacity, etc. The choice of the type of soil can be made using the data on the classes, distinguished by the parameters of the stability of the functioning of the soils. The approach will allow making a rational choice of soils from all their diversity. According to the degree of stability and development, it is proposed to use contrasting options for soils, taking into account the area they occupy. The functional-ecological approach does not imply the choice of a specific soil characteristic, but takes into account the cumulative assessment of all soil properties according to the principle of their sustainability. In addition, it is advisable to create a network for hygienic rationing and maintain a database of the results obtained throughout the country. The main databases for the literature search were Scopus, Web of Science (WoS), Global Health, CyberLeninka, scientific electronic library elibrary.ru (RSCI). Since this topic affects the formation of an approach in the guidelines for determining the maximum permissible concentration, the review publication included information on National Russian standards, educational (national Atlas of soils of the Russian Federation, WRB - World Reference Base of Soil Resources) and scientific literature.

Many different chemical pollutants get into the hydrosphere with wastewater. An essential source of xenobiotic transfer into the aquatic environment is wastewater treatments plants. The widespread use of drugs, personal care products, cosmetic products, household chemicals, disinfectants and insecticides is directly reflected in their presence in the aquatic environment. It is the reason for the appearance of these chemical components and products of their transformation in surface waters, groundwater, and drinking water. Besides, various industries lead to the formation of a large amount of wastewater contaminated with textile dyes, oil products, silicones, phenols and their derivatives, phthalate ethers, bisphenol A and other substances capable of causing harm to water bodies, harming aquatic biota or even inflicting damage to ecosystems. Substances that have entered wastewater can be transformed into many other compounds during water purification and afterwards under environmental factors. The transformation products can be more toxic than the parent compounds, and some can convert back to the parent compounds under various factors. The search of sources describing researches dedicated to pollutants and their transformation in aqueous systems was carried out in the English-speaking text databases: PubMed, Scopus, Science Direct, Web of Science, Research Gate, Springer Link and scientific electronic library - eLIBRARY.ru.

In the modern economic system, the concept of developing high-technology production shapes the competitiveness and outlook of national economic development. The specifics of high-technology production imply considerable risks emerging across the lifecycle, which requires risk management. The paper explores the aspects of businesses engaged in high-technology production and the risks involved. A classification of risks is proposed for high-technology production in accordance with the requirements set in standard GOST R ISO 9001-2015.

The article presents the results of a review of domestic studies of adherence to treatment in 2010-2020. Authors given the definition of the concept of «compliance». We have identified the key areas of science that are involved in compliance research. Also reviewed the authors research, which describe the structure of compliance, approaches to its study and factors affecting compliance.

Teratomas are tumors which are composed of tissues derived of more than one germ cell layer; they appear between 3-6 weeks of pregnancy and are present more often in females. A prognosis for life depends on the timely diagnosis of the mass and a possibility of surgical treatment. An article presents a case of a female neonate born with severe respiratory insufficiency. Antenatal ultrasound at 19-20 and 30-31 weeks exposed the myoma of the uterus and a probability of large birth weight. Immediately after birth a neonate requested urgent intubation, artificial lung ventilation, intensive therapy for hemodynamic stabilization. The thoracic surgeon suspected the presence of cystic adenomatous malformation upon the chest X-ray and clinical observation data and defined expectant management and prolongation of intensive therapy. Autoptical evidence is a large mediastinal teratoma 10×8×5 cm, weight 135.0 gram, moderate secondary hypoplasia of lungs. Histological processing revealed mass lesion of the anterior mediastinum in a capsule, which was presented with immature discohesive mesenchyme with lymphoid assembly, brain tissue and multiple cysts of different size with inclusions of cartilage tissue. Effective correct and precise antenatal visualization, which can defined the type of maternity hospital, postnatal MRT and timely provided therapy intervention surgical mass removal including — these are key factors of successful management newborns suffering from anterior mediastinal teratomas. The research was carried out in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Local Ethics Committee of these Institutes. The informed consent of the patient was obtained for conducting the studies. No conflict of interest was declared by the authors. Key words: newborn, mediastinal teratoma, diagnostics, therapy.

Introduction. One of the important steps in assessing the nanoparticles (NP) safety is the analysis of mutagenic activity, including the evaluation of gene, chromosomal, and genomic mutations. Material and methods. The purpose of this investigation is to study the ability of different NP aqueus suspensions and the same compounds in microforms to unduce gene mutations in Salmonella/microsome test (Ames test). Anatase titanium dioxide NP coated with simethicone (33.16 ± 16.7 nm, 5-50000 μg/ml), magnetite NP coated with silicate (10 nm, 0.92-575 μg/ml), silver NP coated with аrabian gum (14 ± 0.2 nm, 5-50000 μg/ml), aluminum hydroxide nanofibres (50-70 nm, 24-3000 μg/ml) and multi-walled carbon nanotubes (Taunit MWСNTs, outer diameter 15-40 nm, inner diameter 3-8 nm, length 2 and more microns, 5-50000 μg/ml). In parallel, the mutagenic activity of equivalent microparticles was evaluated in experiments. Ames test (Salmonella/microsomes) registers gene mutations induced by a different mechanism of action, in the variant with preincubation. A set of Salmonella typhimurium indicator strains: TA 100 (base pair substitution mutations), TA 98 and TA 97 (mutations of the frameshift type of the genetic code) were used. Using addition the S9 microsomal activating mixture during the experiment makes it is possible to determine the effect not only of the substances themselves, but also of their metabolites. Conclusion. The investigated nanomaterials as well as their micro analogs in the studied dose range did not induce gene mutations in the Ames test both in presence and absence microsomal activating mixture.

Introduction. The toxicity of carbon nanotubes (CNT), which are chemically inert particles, is thought to be connected with responses of aseptic inflammation and oxidative stress. This study was conducted to determine how far antioxidants may reduce CNT toxicity in laboratory animals. Material and methods. Male Wistar rats were administered by oral gavage with 0.05 or 0.5 mg/kg/day of Tuball© single-walled CNT in vegetable oil for 2 weeks, without a modifier or in combination with Aevit© (mixture of retinol and α-tocopherol given in doses 25,000 IU/kg/day and 25 mg/kg/day correspondingly). Control animals received oil or Aevit without CNT. 10 markers of oxidative stress and 12 clinical chemistry markers were determined in the rat blood samples. Results. Aevit didn’t influence the above biochemical markers, but combination “Aevit + CNT” increased the prooxidant action of CNT and arose biochemical signs of malabsorption, presumably as a result of retinol inhibitory action onto repair of intestinal epithelial cells, damaged by CNT. Discussion. The lack of tocopherol protective action, which usually removes prooxidant effects of high retinol concentrations, can be explained by superposition of two mechanisms: 1) two components of Aevit, in the presence of CNT, may be separated in space, since only retinol has isoprenoid side chain needed for the formation of donor-acceptor complexes with CNT surface; 2) the effects of retinol on cell reproduction, differentiation and wound healing is not related to its anti - or pro-oxidant properties but takes place at the level of target genes transcription after binding of retinoic acid with nuclear receptors RARs and RXRs. The data obtained allowed supposing the mechanism of lung cancer increases in ATBC and CARET trials was not prooxidant action of retinol and its precursor β-carotene, but regulatory inhibition of lung epitheliocytes reparation during its continued damage by cigarette smoke and asbestos fibers by retinoic acid. Conclusion. Aevit (and, probably, other retinoid-containing preparations) can’t be recommended to ensure the safety of humans and animals during oral CNT intake. The results obtained explanation needs both functional activities of retinol, which is simultaneously antioxidant and one of the nuclear regulators; this, in turn, leads to the new assumption about the mechanisms of unsuccessful outcomes in ATBC and CARET trials.

This review is designed to discuss possibilities for the treatment of advanced gastric cancer with reference to the prognostic and predictive value of molecular-biological parameters and the influence of hereditary predisposition to the development of neoplastic process. The data on modern pharmacotherapy of this disease based on the knowledge of molecular-biological parameters are presented including the following markers: HER2/neu, VGFR, c-met, TUBB3, CDH-1, BRCA-1, EGFR, TGF-ß, p53, Ki67 and PCNA. It is emphasized that the role of molecular-biological parameters associated with advanced gastric cancer is ambiguous. The prognostic and predictive significance of some of the markers is confirmed while that of others remains to be elucidated and requires further research.

The paper presents the Paris System for Reporting Urinary Cytology developed by the joint efforts of cytologists, pathologists and urologists in April 2016. We describe 7 accepted categories of cytological diagnoses, the risk of malignancy and recommended clinical management of patients with urinary pathology.

For the first time in Russia the immunophenotype of tumor infiltrated lymphocytes (TIL) was investigated with the use of a method of quantitative flow cytometry. Samples from 104 patients, suffering from solid tumors (such as breast cancer, ovarian cancer, melanoma and oral cavity squamous carcinoma), were analyzed in this investigation. In the difference of cytomorphological analysis, the method of flow cytometry identified TIL in 100% of cases. In the structure of CDS+Т- lymphocytes the ratio CD4/CD8 was equal to 1,1±0,1. Serial gating strategy allowed to assess minor subpopulations of regulatory T-lymphocytes CD45+CD4+CD127+low/neg and CD45+CD8+CD28-CD11b-. Regulatory mechanisms with involvement of CD8 T-cells played the main role in the generation of immune responses at the tissue level ofpatients, suffering from solid tumors, independent of nosological form of disease.