Том 98, № 8 (2019)

Мұқаба

PROBLEM-SOLVING ARTICLES

Problems and prospects of training specialists in preventive toxicology

Onishchenko G., Nikolayeva N., Khamidulina K., Filin A., Korolev A., Nikitenko E.

Аннотация

The new chemical threats, existing and constantly emerging to public health require the improvement of the system of training specialists in the field of preventive toxicology. Preventive toxicology is an independent discipline. However, medical and preventive doctors carrying out hygienic regulation, assessment of toxicity and hazard of chemicals and dealing with prevention and risk assessment of the effects of xenobiotics on human health, have only basic toxicology training. Currently, in the nomenclature of the professional standard in the specialty “Medical and Preventive Business”, the specialty “Preventive Toxicology” is absent, and the number of hours allocated for studying this section is very limited.Diploma education in the field of preventive toxicology is carried out on the basis of the Federal State Educational Standard of Higher Education in the specialty “Medical and Preventive care”, within the framework of which specialized hygienic disciplines with components of preventive toxicology are taught. At the postgraduate education stage, issues of chemical safety and preventive toxicology are addressed only in selected educational institutions, for example, on certification cycles in hygienic specialties, as well as on short-term specialized advanced training cycles.At the Department of Human Ecology and Environmental Hygiene of the I.M. Sechenov First Moscow State Medical University, a separate training module on preventive toxicology was developed and introduced into the educational process. One of the main objectives of the development of this curriculum was the formation of the students’ algorithms for conducting toxicological research and approaches to the evaluation of the results. At this stage of the training, students study in-depth laboratory toxicological methods, the adaptation mechanisms of the organism, and questions of extrapolation of human data obtained in animal experiments, the pathogenesis of intoxication and long-term effects of exposure to harmful substances. The analysis of the system of training specialists in the field of preventive toxicology suggests the need to improve the forms and methods of teaching students, primarily through the development of skills to work with data registries and toxicological laboratories, using the capabilities of research institutes and institutions of the of the Federal Service for Supervision of Consumer Rights Protection and Human Welfare
Hygiene and Sanitation. 2019;98(8):799-803
pages 799-803 views

ENVIRONMENTAL HYGIENE

Hygienic assessment of the safety and efficiency of using ultraviolet plants of the closed type for dsinfection of the air environment in the rooms of inpatient facilities

Rakhmanin Y., Kalinina N., Gaponova E., Zagainova A., Nedachin A., Doskina T.

Аннотация

Introduction. The paper presents the results of the evaluation of the safety and efficiency of using UV irradiators-recirculators of a closed type, used for disinfecting air in the premises of medical facilities.

Material and methods. The studies included three types of UV irradiators-recirculators of the closed type of various brands. The safety assessment included: 1) ultraviolet radiation measurements; 2) the influence of devices on chemical pollution of indoor air; 3) the impact on the natural gas composition and microclimate; 4) measurement of ozone concentrations; 5) measurement of electromagnetic radiation; 6) measurements of sound levels.

Evaluation of the effectiveness of disinfection was performed on the total microbial number; the content of mold fungi and coliphages per 1 m3 of air.

Results. A safety assessment of the operation of closed-type ultraviolet irradiators-recirculators showed  the devices under study, equipped with zone-free mercury lamps to be not sources of ozone and nitrogen dioxide emission into the air. However, from the bodies of two of the investigated devices, UV radiation with a wavelength of 200-280 nm was detected. It is established that UV irradiators-recirculators of the closed type can be sources of increased noise and electromagnetic radiation. The intensity of these factors inside of premises depends on the distance to the operating device. It is established the safe operating distance of such devices. It has been revealed that long-term operation of closed-type UV irradiators-recirculators can give rise elevation of the ambient air temperature and an increase in the concentration of saturated and acyclic hydrocarbons in the air. As a result of the evaluation of the disinfecting effect of the studied UV irradiators-recirculators, a different degree of effectiveness of their influence on the bacterial and fungal flora was established.

Conclusion. The necessity of developing a methodological document regulating the procedure and scope of research in assessing the safety and efficiency of using UV irradiators-recirculators of a closed type for disinfecting air in medical institutions in the presence of people is substantiated.

Hygiene and Sanitation. 2019;98(8):804-810
pages 804-810 views

EXPERIMENTAL INVESTIGATIONS

Experimental hygienic estimation of calcium and magnesium concentrations in drinking water, and its hardness

Trofimovich E., Nedovesova S., Aizman R.

Аннотация

Introduction. The lack of hygienic norms for Mg2+ and Ca2+ in drinking water and the wide ranges of acceptable hygienic norms (AHN) of these cations in water packaged in containers determine the relevance of experimental studies on the substantiation of AHN of Mg2+, Ca2+ and the hardness of drinking water with a centralized water supply to the population.

Material and methods. Chronic experiments were performed on 5 groups of adult Wistar rats (n = 50): control animals received drinking water (Ca2+ 20.0; Mg2+ 6.0 mg/dm3, hardness 1.5-1.8 mEq/dm3); four other groups received model drinking water with different contents of Ca2+ (50, 80, 100 and 140 mg/dm3) and Mg2+ (20, 40, 55 and 85 mg/dm3) by adding CaCl2 or MgSO4 salts to the control water. The effect of these drinking water samples on kidney function, ion osmotic blood parameters, plasma metabolites of lipid and protein metabolism, as well as the concentration of thyroid hormones (T3 and T4) and cortisol were studied.

Results. Prolonged action of increased concentrations of Ca2+ and Mg2+ on the organism was established to cause alterations in fat metabolism, the adaptive activation of osmoregulatory and ion regulatory kidney functions, increasing the concentration of thyroid hormones and a decrease of cortisol titer in plasma. Magnesium led to more pronounced changes in water-salt metabolism, and at a concentration of 85.0 mg/dm3 (7.0 mg-Eq/dm3) – to depletion of secretion of the described hormones.

Conclusion. Based on the obtained results, individual ranges for AHN of calcium and magnesium concentrations in water were recommended. The upper limit of AHN of drinking water total hardness is of 7.0 mg-Eq/dm3 at the joint presence of Ca2+ and Mg2+. The rule of hygienic qualitative and quantitative estimation of calcium and magnesium types of drinking water hardness is formulated.

Hygiene and Sanitation. 2019;98(8):811-819
pages 811-819 views

The role of adrenocortical hormones in the regulation of organism response to intratracheal injections of electrolysis dust to Wistar rats

Khripach L., Knyazeva T., Zheleznyak E., Koganova Z., Pinigin M., Fedotova L., Budarina O., Sabirova Z., Shipulina Z.

Аннотация

Introduction. Adrenocortical hormones play a leading role in the adaptation of human organism to damaging factors.

The aim of this study is to compare levels of cortisol and biochemical markers of organism damage (MOD) in blood samples of rats under a model of electrolysis dust (ED) inhalation exposure. ED being component of emissions in aluminum production and has high content of resinous substances (RS), including 3,4-benzpyrene.

Material and methods. Male Wistar rats were injected ED intratracheally once per month, in doses corresponding to keeping of animals at ED concentrations of 1.0; 5.2 and 25.1 mg/m3, calculated on RS mass. 2 weeks after the 1st and 2nd ED administration and 6 days after the 3rd one, blood serum samples were used for determination of cortisol levels (ELISA) and the following 6 MOD: the intensity of luminol-enchanced chemiluminescence, activities of catalase, N-acetyl-β-D-glucosaminidase (NAG), acid DNAse, acetylesterase and γ-glutamyl transferase (GGT).

Results. 2 weeks after the 1st and 2nd ED administrations (cortisol content 2 times reduced or not changed), similar significant changes were observed in almost all MOD; 2nd experimental point, if comparing with 1st point, had slight increase in oxidative stress and significant rise in GGT activity (a marker of precancer changes) at the maximum dose. On the contrary, 6 days after the 3rd injection of ED, in parallel with the increase of cortisol content in rat blood by 1.5 - 2 times, small significant changes were found for only one marker (NAG). The obtained data fit into existing concepts about protective role of cortisol and biphasic nature of its release into the blood, allow us to consider the absence of MOD, in parallel with rising levels of C, as a transit phase and have common problem aspects with CIRCI syndrome (Critical illness-Related Corticosteroid Insufficiency) in emergency medicine.

Conclusion. Determination of cortisol levels by ELISA assay can be easily incorporated into any toxicological protocol as index of organism adaptive response, but further investigations are needed to clarify its characteristics and to build continuous model from separate time-dose points.

Hygiene and Sanitation. 2019;98(8):820-826
pages 820-826 views

POPULATION HEALTH

Monitoring health indices in females of different age groups

Aminova O., Tyatenkova N., Uvarova Y., Yakovlev S.

Аннотация

Introduction. Health - is a complex and at the same integral multivariable dynamic state, developing in the process of realization of the genetic potential in a particular social and ecological environment, which permits a person to carry out its biological and social functions.

Material and methods. Health indices deteriorate with age. In this situation, special attention should be paid to older age groups. However, recent studies prefer to investigate young people. Data about health status of different age groups is not well investigated. Survey of 415 women aged 20 to 59 years residing on Yaroslavl region has been performed. Evaluation of age-related changes in health indices included questionnaire, morphological and functional examination, definition of physical development and adaptative potential according to the calculated indices and reference values.

Results. The study examined the dynamics of health indices and established a statistically significant difference in the gain in body weight, blood pressure, total blood cholesterol, decreased lung capacity relative to body mass and adaptive capacity of the cardiovascular system with the age. Analysis of the incidence showed that chronic diseases incidence has increased from 56% in the 20-29 years group to 88% among 50-59 years old persons. Diseases of cardiovascular and musculoskeletal system (48-49%) become predominant pathology with age. Evaluation of lifestyle shows that poor physical activity and sleep disorders were registered in 77% and 32% respectively regardless of age. Eating disorders were registered in 41% patients aged of 20-29 years. Ratio tobacco users decreased from 23% to 10% with age, while the number of cigarettes smoked per day was increased.

Сonclusion. The study established the negative dynamics of health indices to be typical for women aged 20-59 years, while the rate of deterioration exceeds the average one in the Russian population. Self-preservation behavior is not predominant in all age groups, it is typical only for 3% of young women and 11-15% of other groups.

Hygiene and Sanitation. 2019;98(8):827-832
pages 827-832 views

Peroxidation of blood lipids in the conditions of application of individual respiratory protection equipment

Byalovsky Y., Kiryushin V., Prokhorov N., Rakitina I.

Аннотация

Introduction. The category of important, but little-studied environmental factors, is the additional respiratory resistance, which is the main factor limiting human performance in the means of individual respiratory protection. Changes in the body that have not been sufficiently studied under conditions of additional respiratory resistance include changes in lipid peroxidation and antioxidant protection. The purpose of this study was to study changes in blood lipid peroxidation using additional respiratory resistance.

Material and methods. The study was conducted on practically healthy subjects of both sexes (78 people), aged from 20 to 36 years. To simulate the conditions of use of personal protective equipment for respiratory organs, inspiratory resistive respiratory loads of 20% of the maximum intraoral pressure were used for the Muller test. The duration of the resistive loads amounted to 3 or 10 minutes. The processes of lipid peroxidation were assessed by changes in the level of malonic dialdehyde, the concentration of free fatty acids, and the dynamics of plasma hydroperoxides. The activity of the antioxidant system was determined by the dynamics of the index of total antioxidant activity, plasma catalase activity. Measurement of serotonin, adrenaline and noradrenaline concentrations in plasma was carried out by the fluorimetric method.

Results. The indices of blood lipid peroxidation are most affected by the duration of use of respiratory protective equipment. Three-minute respiration in the means of individual respiratory protection significantly changed the processes of peroxidation of blood lipids in the direction of inhibition. In particular, there was decreased the concentration of malonic dialdehyde decreased (p <0.01); concentration of free fatty acids (p <0.001), and activity of lipid hydroperoxides (p <0.0001). Under a ten-minute use of personal respiratory protection, the processes of blood lipid peroxidation almost did not change: the content of lipid hydroperoxides and malondialdehyde remained unchanged (p> 0.05) from the initial level.

Conclusion. The antioxidant effects of the values of increased resistance to breathing used by us indicate to the absence of hypoxic stimulation under the action of moderate resistive loads, and resistive stimulation of antioxidant mechanisms. We assume that during the action of resistive respiratory loads, the metabolic function of the lungs is activated, which is associated with increased resorptive processes in the pulmonary vessels, which leads to an enhanced release of biologically active substances from the lungs with antioxidant activity. Enhancement of the absorption of endogenous antioxidants against the background of resistive respiratory loads is a protective response against lipid peroxidation.

Hygiene and Sanitation. 2019;98(8):833-838
pages 833-838 views

The influence of seasons on the development of exacerbations of the most common diseases of the circulatory system. Gender and age peculiarities

Gruzdeva A., Saltykova M., Bobrovnitskii I., Balakaeva A., German S.

Аннотация

Introduction. The aim of the study was to assess seasonal differences in the exacerbations rate of diseases of the circulatory system (DCS), taking into account the nosological form (ICD code), gender and age of patients.

Material and methods. 428 727 emergency medical service (EMS) calls to patients with exacerbations of DCS in Yaroslavl for the period 2012-2017 were analyzed. The EMS calls to men and women were analyzed separately. Four groups were identified: AH (arterial hypertension), CHD (coronary heart disease), RD (rhythm disturbance), CVD (cerebrovascular disease), which were divided into age subgroups. To assess the impact of the seasons of the year, the subgroups “winter” (all emergency calls in the winter period (from December to February) and “summer” (all emergency calls in the summer period (from June to August) were additionally identified.

Results. The calls due to an elevated arterial blood pressure were most frequent among all the EMS calls from DCS patients. Among them, in all age subgroups older than 40, there were significantly more calls from women, while the calls for exacerbation of other DCS were significantly higher from men. In winter, the number of EMS calls for arterial hypertension was significantly higher than in summer in all age subgroups of men and women older than 40 years. For other analyzed DCS, such regularities were not detected.

Conclusion. The patterns revealed in this study should be taken into account both in clinical and preventive practice, and in the organization of work of emergency medical service.

Hygiene and Sanitation. 2019;98(8):839-844
pages 839-844 views

OCCUPATIONAL HEALTH

The selection of the respirators as a result of studies of their workplace protection factors (review)

Kaptsov V., Chirkin A.

Аннотация

Currently, respiratory protective devices (RPD) play an important role in the system of the workers’ protection from the polluted atmosphere in the Russian Federation. The article describes the history of evaluation of workplace protection factors (WPFs) in USA and UK, and their impact on the law requirements for the employers (in developed countries), that determine the selection of RPD for known workplaces’ conditions. WPFs measurements revealed a low efficiency of the four types of RPD compared to measurements in laboratories. This difference prompted a change in the requirements for employers. The Assigned Protection Factors of three types of Powered Air Purifying Respirators (PAPRs) were reduced: for PAPRs with a full facepiece - from 2000 to 40; for PAPRs with hood or helmet - from 1000 to 25; for PAPRs with half mask - from 500 to 50. The Assigned Protection Factor of gas masks was reduced from 900 to 40. Western requirements for selecting RPD are compared with the practice and recommendations for choosing RPD in the RF. There were revealed significant differences increasing the risk of acute poisoning and the development of chronic diseases among workers. Specific recommendations are given to reduce these risks: reduction of air pollution in the workplaces; development of requirements for the selection of RPD in the RF, based on the best Western requirements; participation of the industrial hygienists in the development of requirements for RPD and training materials for the specialists and workers; development and implementation of the Biological Exposure Indices.
Hygiene and Sanitation. 2019;98(8):845-850
pages 845-850 views

The severity of endogenous intoxication and oxidative stress in the blood of workers in contact with glycine derivatives

Miroshnikova D., Kiryushin V., Prokhorov N., Fomina M., Motalova T., Bolshakov A.

Аннотация

Introduction. Currently, the search for markers of the health status of workers in agro-industrial complexes in contact with pesticides continues.

The aim of this study was the assessment of the effect of glyphosate isopropylamine salt on the health of workers in agroindustrial complexes of the Ryazan region according to the severity of endogenous intoxication and oxidative stress in the body.

Materials and methods. Plasma and erythrocytes of peripheral blood of workers were the clinical material for the study. Blood was taken in 87 workers contacted with glyphosate-containing pesticides. As a control group, 20 clinically healthy individuals of the same age category who did not have contact with the pesticides were selected to be studied. The severity of endogenous intoxication was determined by the level of substances of low and medium molecular weight in the plasma and red blood cells. The severity of oxidative stress was determined by the content of the products of oxidative modification of proteins by the method of R.L. Levine modified by E.E. Dubinina.

Results. Statistically significant changes in the severity of endogenous intoxication in the blood plasma and erythrocytes of the study groups and the control group of individuals among machine operators and workers who come into contact with pesticides to a lesser extent were obtained. A statistically significant increase in the level of carbonyl derivatives compared with the control among machine operators who have greater contact with glyphosate-containing pesticides according to the time sheets has been revealed. The level of secondary carbonyl derivatives in machine operators was higher than that of warehouse workers and was statistically significant.

Conclusion. A statistically significant increase in the level of secondary carbonyl derivatives among machine operators as compared with other workers is a late marker of oxidative stress, which indicates to a depletion of the reserve forces of the body. This may be due to longer contact with pesticides based on glyphosate machine operators as compared to other workers in the agro-industrial complexes.

Hygiene and Sanitation. 2019;98(8):851-856
pages 851-856 views

HYGIENE OF CHILDREN AND ADOLESCENTS

Modes of use of the cell phone and health of schoolchildren

Vyatleva O., Kurgansky A.

Аннотация

Introduction. The broad spread of cell phones (CP) among schoolchildren and the absence of age standards for their safe use determined the purpose of the study: to reveal the regimens of CP use, critical for the health of children and adolescents.

Material and methods. In a cross-sectional study in 2008-2010, by the questionnaire data of 2,137 schoolchildren aged 6-15 years there was assessed the impact of CP usage indices (daily number of calls - CN, call duration - CD, and total daily duration of calls - TCDD) on health (the incidence of headaches and sleep disorders, number of colds). Student and Mann-Whitney criteria and assessment of relative risks were used.

Results. The study revealed age-dependent critical values of usage indices (in 6-10 years: CN=2, TCDD=6 minutes.; in 11-13 years: CN=6; in 14-15 years CN=6, CD=3 minutes., TCDD=4 -10 min.), the exceeding of which due to risks: in 6-10 years - to have more than 4 colds a year (OR 2.25, 95% CI 1.09-4.62); in 11-13 years to have several headaches per week (OR 1.61, 95% CI 1.12-2.30); in 14-15 years - to have several headaches (OR 1.79, 95% CI 1.27-2.54) and several sleep disorders (OR 1.66, 95% CI 1.17-2.37) per week.

Discussion. Age differences in critical modes of CP use and in health violations, as well as the importance of radiation intensity are discussed.

Conclusions. Age-related CP use regimens, critical for health, were established. It was shown the need to develop more precise age criteria for safe CP use with taking into account a wider range of health indicators and radiation intensity.

Hygiene and Sanitation. 2019;98(8):857-862
pages 857-862 views

Estimation of efficiency of osteopathic correction of functional state of student organism under increased psycho-emotional loads

Egorova I., Buchnov A., Buynov L., Plakhov N., Usachev V., Mikhailova E., Sorokina L.

Аннотация

Introduction. The social changes happening in the country for the last 25 years negatively affected the state of health of citizens, mainly younger generation. It is expressed in the gain in the morphological and functional of deviations, the general incidence of teenagers, deterioration in psychosomatic health of youth as a result of high compensatory and adaptive exertion up to nervous breakdowns.

Purpose. To estimate efficiency of correction of a functional condition of an organism of students by means of osteopathic influence at the raised psychological and emotional loads during exams.

Material and methods. 15 almost healthy students of pedagogical higher education institution, at the age of 22.4±0.7 under increased psychological and emotional exertion during exams acted as examinees. Changes of indices of the osteopathic status and a functional condition of the central nervous system of students directly before osteopathic correction, right after influence and also in 3 weeks were estimated.

Results. The osteopathic correction was established to promote a significant improvement in students according to values of indices of functional mobility of nervous processes in the cerebral cortex; a mental state on nosological and syndromologic scales; - indices of the osteopathic status

Conclusion. Single osteopathic correction leads to optimization of the mental status, mobility, and steadiness of nervous processes, and also to reduction of processes of excitement in a cerebral cortex both right after influence and in 3 weeks after its carrying out. Also improvement of attention and memory in students in 3 weeks after an influence, and right after carrying out correction - decrease in an uneasiness index in them and the general functional status is noted. Results of research revealed need of carrying out further research on the development of the modes of correction for the purpose of the introduction it in educational process.

Hygiene and Sanitation. 2019;98(8):863-869
pages 863-869 views

FOOD HYGIENE

Hygienic assessment of the thermos car for transporting food products

Tikhova T., Kaptsov V., Korotich L., Leksin A., Morgunov A.

Аннотация

Recently, due to the increasing volume of traffic and the lack of specialized transport, new engineering solutions are being sought, one of which is the modernization of the existing fleet of thermos cars to extend their service life. The aim of this study was the hygienic assessment of the modernized thermos car model 16-6894 for its compliance with the current Rules for the carriage of perishable goods by rail. Perishable goods include food products requiring compliance with certain temperature and humidity conditions during storage and transportation. To confirm the compliance of the temperature in the thermos car with the requirements of sanitary and hygienic rules and regulations, a corresponding study was conducted. According to a special program, tests were carried out to determine the time of heating the air in a thermos car using a simulator of deep-frozen products (frozen water) in order to further establish the deadlines for transportation in the summer and transitional periods of the year. The result of the research was the development of computer software that allows predicting the timing of transportation of any frozen food for certain specified conditions.
Hygiene and Sanitation. 2019;98(8):870-872
pages 870-872 views

Prevalence and forecasting of alimentary risk factors among patients with myocardial infarction

Ivanenko A., Goloschapov-Aksenov R., Kicha D.

Аннотация

Introduction. The high incidence of myocardial infarction (MI) in the population is largely determined by the significant prevalence of risk factors, including alimentaryones. Risk factors for MI are widely studied, however, forecasts of outcomes of MIare not associated with the prognostic significance of specific factors. Estimates have shown the prognostic significance of priority risk factors for myocardial infarction to remain virtually unexplored.

Material and research methods. The object of the study was MI patients treated in hospital. The volume of the study was 162 MI patients (main group) and 140 practically healthy individuals (control group). The subject of the study was the calculation of prognostic coefficients (according to a special formula) based on the analysis of nutritional risk factors for myocardial infarction and an assessment of their prognosticity and prevalence. The sociological method-questioning of patients was applied.

Results. The frequent consumption of salty and fatty foods, butter, a large amount of carbohydrate products, the presence of 2nd and 3rd degree obesity patients were establish to have the greatest prognostic value in MI patients. Monitoring highly predictive nutritional risk factors for MI allows identifying the priority preventive impacts, which, in addition, will not be passive, but active. The methodology for predicting the degree of risk of nutritional factors is confirmed in the context of comparative studies of experience and control groups.

Conclusion. The identification of these nutritional risk factors in a patient visited the polyclinic allows attributing it to a risk group for the development of myocardial infarction with subsequent targeted laboratory and instrumental examination and registration with the dispensary. Assessment of the prevalence and prognostic significance of nutritional risk factors among MI patients provides opportunities for early detection of health abnormalities and the development of preventive actions.

Hygiene and Sanitation. 2019;98(8):873-877
pages 873-877 views

PREVENTIVE MEASURES

Estimation of the efficiency of the dry method of decontamination of surface contamination of alpha-emitting-radionuclides

Korenkov I., Lashchenova T., Shandala N., Ermakov A., Mayzik A.

Аннотация

The article describes the evaluation of the efficiency of using the technology of dry method of decontamination of α-radionuclides from working surfaces of premises for different materials, equipment and building structures.

Materials and methods. Instruments for measuring of ambient dose equivalent rate (ADER) with a lower limit of 0.03 μSv/h. Specific activity of α-radionuclides in the samples was determined by radiometric, radiochemical and spectrometric methods using standard methods in the accredited laboratory. The measurements in situ were also carried out using the ISOCS «CANBERRA» mobile gamma-ray spectrometry system with high purity germanium detector and a collimator. Technological equipment included industrial vacuum cleaner with nozzles; high-pressure device; packing sets for RAW collection; HEPA filters; personal protective equipment.

Results. Maps of spatial distribution of surface α-contamination in the building was constructed. We performed cluster analysis of data for zoning of contaminated surfaces. The decontamination factor for porous (brick, concrete), smooth (wood, brown tiles, laminate) and sticky (bitumen, mastic) surfaces was determined.

Conclusion. The cluster analysis made it possible to identify 4 levels of surface α- and β- contamination, particles/cm2 ∙ min: zone I - for α- above 50, for β- above 10,000; zone II - for α- 5-50, for β- 2,000-10,000; zone III - for α- no more than 5, for β- 2000; zone IV - corresponds to the background values of the workspace surfaces. The dry decontamination method revealed a high content of fine dust aerosol fraction deposited in the lungs. To increase the efficiency of dust suppression, water aerosol with droplet size of 100 - 400 microns and quartz sand with particle size of 100-200 microns were sprayed at the rate of 200-400 g per 1 m2. The decontamination coefficient depends on the coating material and the level of surface contamination: concrete - 91 to 97.8%; brick - 85-86%, wood - 38.8-53%; brownstone tiles - up to 29%; mastic - 22-28%; bitumen - 15.9-20%. To protect the personnel, radiation-hygienic rationing of PM10 and PM2,5 content is necessary.

Hygiene and Sanitation. 2019;98(8):878-884
pages 878-884 views

The effect of fluoride and hydroxyapatite in the composition of toothpastes on the remineralization and acid resistance of enamel

Polyakova M., Babina K., Makeeva I., Prochorov N., Novozhilova N., Doroshina V., Arakelyan M.

Аннотация

Introduction. The use of toothpastes is the most common way for the prevention of caries. There is a variety of different toothpastes available on the market and the choice of the most efficient paste for the particular case is of great interest and importance.

Aims: the purpose of the study was to assess the impact of toothpastes containing hydroxyapatite and fluoride on resistance of enamel to demineralization and enamel remineralization rate.

Material and methods. One hundred sixty patients participated in the study. The test and control groups included 80 patients each: 40 - at the age of 15-17 and 40 at the age of 18-25 who have been using toothpastes with hydroxyapatite or fluoride during 1 year, respectively. The oral hygiene assessment was carried out with the use of Turesky index. The clinical determination of enamel remineralization rate, and enamel resistance to demineralization were assessed to evaluate the remineralizing potential of toothpastes containing hydroxyapatite or fluoride.

Results. There was a statistically significant increase in the values of enamel resistance to demineralization and remineralization rates in all groups comparing to the baseline after 1-3 months of the use of the toothpastes prescribed. It was found that enamel resistance to demineralization and remineralization rates of enamel in the test group were significantly higher (p<0.05) compared with the group of patients using the toothpaste with fluoride.

Conclusion. Use of toothpastes containing hydroxyapatite and fluoride in conjunction with constant control of oral hygiene significantly increased the enamel demineralization resistance and enamel remineralization rate. However, toothpastes with hydroxyapatite were significantly more efficient and exhibited its action earlier in time.

Hygiene and Sanitation. 2019;98(8):885-892
pages 885-892 views

The use of agents based on the bacterium Bacillus thuringiensis var. israelensis for mosquito control

Roslavtseva S.

Аннотация

Mosquito control is necessary to improve the epidemic and, consequently, the sanitary and hygienic situation in human settlements. At the same time, the safest and more environmentally friendly way of controlling is not the fight against adult mosquitoes, but the treatment of reservoirs with microbiological larvicides based on entomopathogenic, aerobic, spore-forming, saprophytic bacteria Bacillus thuringiensis (de Barjac) (Bti). A new serotype of the bacterium B. thuringiensis was found in Israel in the Negev desert. This serotype being more active against larvae of blood-sucking and non-blood-sucking mosquitoes and midges than previously known serotypes, was named israelensis. Bti endotoxin is a typical insecticide with intestinal type of action for different mosquito species. For example, Bti H14 is highly insecticidal to the larvae of Aedes aegypti and Ae. albopictus at very low concentrations. The parasporal body (endotoxin crystal), a crystalline protein consisted of four main polypeptides and two minor polypeptides, possesses of a larvicidal action. Larvicidal activity is associated with a synergistic effect in a combination of four polypeptides. The possibility of development of resistance to products based on Bti and Bacillus sphaericus in populations of mosquitoes (Culicidae) was investigated. The use of domestic microbiological formulations based on Bti («Baktitsid», «Larviol-pasta», and «Antinat») was shown an eradication the larvae of bloodsucking mosquitoes and midges to be possible and rational, since they are not generated resistant populations of mosquitoes. This is confirmed by more than 30 years of the use of such formulations.
Hygiene and Sanitation. 2019;98(8):893-896
pages 893-896 views

Earthworms ecological and epidemiologic contribution to prevention of toxocariasis

Erofeeva V., Maslennikova O.

Аннотация

Introduction. Morbidity toxocariasis, second in prevalence geohelminthiasis in Russia, is a serious problem in recent years, especially in metropolitan areas. The involvement of earthworms in the life cycle of toxocarias remains poorly understood. The role of earthworms (paratenic hosts) in the circulation and prevention of toxocariasis is established. The work is aimed at a contribution finding out of earthworms Еisеniа fеtidа (paratenic hosts) in toxocariasis circulation and prevention.

Material and methods. Nematodes dehelminthization derived from animals. For the first time in Russian Federation, experiments have been conducted on infestation of earthworms Е. fеtidа with infective eggs Tоxоcаrа cаnis and Tоxоcаrа mystax.

Results. In the conducted experiments, possibility is proved of infestation of earthworms Е. fеtidа with infective eggs Т. canis and Т. mystax via earth bacterized with 10000 infective eggs. For the first time migration was proved of ascaridate larvae from intestines to skin-muscular sac of the earthworms.

Conclusion. Besides, investigation was conducted aimed at finding out of the period duration of Т. canis and Т. mystax larvae staying in earthworms’ intestines and sinews.

Hygiene and Sanitation. 2019;98(8):897-902
pages 897-902 views