卷 68, 编号 4 (2023)

The article is dedicated to the jubilee event - the 95th anniversary of a world-famous scientist, an outstanding figure in the national medical science, one of the pioneer organizers of healthcare and the creators of the nuclear shield of our country, our Teacher – Academician Leonid Andreyevich Ilyin.

Purpose: To justify the necessity to update the radiation safety standards in our country and to propose the main directions for revising the Russian regulatory framework in the field of radiation safety.

Material and methods: This paper considers the phases of development of the radiation safety regulation system in Russia. It is noted that for the first time a full-fledged three-level system of radiation safety regulation was created in Russia in the early 2000s. A generalized analysis of new international documents in the field of radiation safety system, which are worth using in the Russian regulatory framework, is presented.

Results: The main directions of the revision of the Russian regulatory framework in the field of radiation safety are:

introduction of new concepts and current terminology;

introduction of “soft” standards, which are reference levels and the so-called “dose constraints” (it is desirable to give this term a different Russian name);

updating the principles and standards of emergency response;

updating the dose coefficients taking into account new biokinetic models, extension of the list of radionuclides and pathways;

introduction of special approaches in the field of internal dosimetry and regulation of radiation protection of workers under management of radionuclides with a long effective half-life of clearance from the human body (isotopes of plutonium and ⁹⁰Sr);

use of principles and standards according to the concept of exclusion, exemption, and clearance to justify the criteria for classifying various media as radioactive waste and waste with a high content of radionuclides;

development of standards and rules for maintaining the radiation safety of workers and the public during the decommissioning of radiation facilities and the rehabilitation of contaminated areas.

Conclusion: For the successful implementation of the work to be done, it is important to combine the efforts of the Russian scientists and practitioners who have accumulated extensive experience in the field of radiation safety. The high potential of the Russian specialists makes it possible to carry out this work in a short time. A necessary condition for the implementation of these works is the introduction of amendments to the Federal Law of 09.01.1996 No. 3-FL «On Radiation Safety of the Public».

Purpose: To assess the state of radiation safety at nuclear facilities of the FSCCRO.

Material and methods: The Federal Scientific Clinical Center for Medical Radiology and Oncology of the FMBA of Russia has three radiation-hazardous facilities on one site, which implies the need for strict compliance with all radiation safety requirements. As a part of the study, the analysis of reports based on the Safety Guidelines for the Use of Atomic Energy, was carried out in order to comply with the requirements of regulatory documents on radiation safety when performing work on the declared types of activities, taking into account the specifics of the institution’s “closed cycle” working mode. The article also presents the annual exposure doses of the category of personnel working with technogenic sources of ionizing radiation (group A) or being under the terms works in the field of their impact (group B) for the period from 2020 to 2022. The analysis of collective and mean radiation doses of the Group A personnel is done for the specified period.

Results: A three-year analysis of the state of radiation safety at the Center showed that the radiation situation at nuclear facilities meets the requirements of the current legislation of the Russian Federation in terms of radiation parameters. There were no cases of exceeding the established control levels of personnel individual radiation doses for the period 2020-2022 as of March 3, 2023.

Conclusion: There are no deviations from the requirements of regulatory documents on radiation safety when performing work on the declared types of activities. The experience of the radiation safety service of the Center can be used when commissioning similar facilities on the territory of the Russian Federation.

Purpose: To study the effect of the radiation dose rate on the dynamics of peripheral blood indicators in various periods of chronic radiation syndrome (CRS), which developed as a result of professional prolonged radiation exposure in a cohort of former employees of the Mayak plant who underwent inpatient examination at the clinic of the A.I. Burnazyan Federal Medical Biophysical Center of the FMBA of Russia in the period up to 1995.

Material and methods: The study of the dynamics of absolute peripheral blood indices in former employees of Mayak plant who were exposed to prolonged industrial radiation with a dose rate of less than 0.001 Gy/day (25 people), 0.003‒0.007 Gy/day (12 people) and 0.008‒0.07 G/day (15 people) during the periods of formation, outcomes and immediate, as well as long-term consequences of CRS.

Statistical processing of the material was performed using the IBM SPSS Statistics software package 23.0 using the Kruskal–Wallis criteria and the Mann–Whitney U-test for independent samples. The results obtained were considered statistically reliable at p < 0.05.

Results: In a group of patients irradiated with a dose rate of 0.008‒0.07 Gy/day during the periods of formation, as well as the outcomes and immediate consequences of CRS, platelet-, leuco- and deep neutropenia were noted. A decrease in the number of erythrocytes and hemoglobin was detected only in the period of outcomes and immediate consequences. The development of agranulocytosis and anemic syndrome are signs that distinguish the course of CRS in this group of patients from the clinical picture of typical CRS. In the period of long-term consequences, 60 % of patients (9 out of 15) developed oncohematological diseases.

At an irradiation power of 0.003‒0.007 Gy/day anemic syndrome was found in 4 out of 12 patients. Leukopenia was observed in the periods of outcomes and immediate consequences. Granulocytopenia was detected in all three periods of the course of CRS. In the long term, 2 patients from this group developed oncohematological diseases

At an irradiation power of less than 0.001 Gy/day shallow thrombocytopenia and neutropenia are noted in the periods of outcomes and immediate consequences of CRS. In the period of long-term consequences, all the average values of peripheral blood indicators correspond to normal levels.

Conclusions: With prolonged irradiation of a person with a dose rate of 0.008‒0.07 Gy/ day or more, with the accumulation of a total dose of 1.7‒9.6 Gy and a contact duration of 6‒96 months, one can expect the development of CRS with a peculiar subacute clinical course of bone marrow syndrome (BMS), manifested by the defeat of all three hematopoietic sprouts, the development of agranulocytosis, anemia and, probably, in 60 % of cases of leukemia development with an unfavorable prognosis for the patient’s life. The main factor determining this feature of the course of BMC CRS is the dose rate, which exceeds 0.008 Gy / day (2 Gr/year).

At a dose rate of 0.003‒0.007 Gy / day (0.7‒1.7 Gy / year), the course of CRS with the development of agranulocytosis is possible in 25 %, anemia – in 33 % of observations. This course of the disease is most likely with a dose rate approaching the upper limit of the named range and high total doses. In other cases, the course of the disease is favorable. In the long-term period, moderate, transient leuko-, neutro- and thrombocytopenia are possible.

With prolonged irradiation with a dose rate of less than 0.001 Gy / day (0.25 Gy / year), the course of the disease is relatively favorable with almost complete restoration of hematopoiesis in the long term.

A meta-analysis of studies of the ‘Standardized mortality ratio’ (SMR, in % compared with the general population) indexes of overall mortality and mortality from all malignant neoplasms for nuclear workers (NW) from 15 countries (for 2007), as well as for workers dealing with the most toxic heavy metals (Hg, Cd, Pb, Cu) and beta-naphthylamine (a carcinogenic antioxidant previously used in the manufacture of paints) was carried out. For NW, a ‘Healthy worker effect’ (HWE) was found for both indexes (SMR = 62 (95 % CI: 56; 69) and 74 (95 % CI: 69; 78), respectively). The obtained SMR values for NW were compared with data for other professional groups (the results of meta-analyses and individual studies with maximum and minimum SMR values: from cosmonauts/astronauts, pilots and athletes, to work with chemical compounds in general or with their individual types (solvents, heavy metals, beta-naphthylamine), as well as with asbestos. It was found that the level of HWE for NW is comparable to that for one group of athletes and is significantly (1.30–1.45 times) higher than for chemical production personnel, although the combined data for NW is not final.

For workers in the chemical industry as a whole, according to published meta-analyses, HWE was also found in SMR, but weak: the value for total mortality was 90 (95 % CI: 87; 92). At the same time, mortality from all malignant neoplasms compared with the population did not reveal a clear HWE, but was not increased either. The most harmful types of employment are, on the rise, work with heavy metals, in coal mines, with beta-naphthylamine and with asbestos.

The data obtained eliminates the prevailing stereotypes and can improve the image of employment in the nuclear and chemical industries in general.

Purpose: To assess the radiation risk of cataracts among the Chernobyl clean-up workers (liquidators), considering the impact of concomitant diseases on this risk and to determine the dose threshold for the development of cataracts.

Material and methods: Radiation risks of cataract incidence were studied in the cohort of liquidators of the consequences of the accident at the Chernobyl nuclear power plant, observed in the system of the National Radiation and Epidemiological Register (NRER) from 1986 to 2021. Among the 62,828 male liquidators, 9,461 new cases of cataracts were detected. The average age of the liquidators at the beginning of exposure was 34 years, the average absorbed dose of external gamma exposure of the whole body was 0.132 Gy, the maximum dose was 1.5 Gy, and the average duration of exposure was 2.5 months. To analyze the relationships of cataract incidence with other diseases and with the dose, a statistical method of link analysis, free from the type of distribution, as well as logistic regression models, were used.

Results: The radiation risk of cataracts in the cohort of liquidators who did not have diagnoses of diabetes mellitus, hypoparathyroidism, malnutrition and myotonic disorders depends on the presence of concomitant diseases in the patient: glaucoma (ICD-10 H40–H42), hyperopia (H52.0), myopia (H52.1) or presbyopia (H52.4). For liquidators with comorbidities, radiation risk is statistically significant only 15 years after exposure, with an excess relative risk of ERR/Gy=0.46 with 90 % CI (0.06; 0.90). For liquidators without comorbidities, ERR/Gy decrease over time: from 4.42 with 90 % CI (0.72; 13.41) in the first 5 years, to zero risk 15 years after exposure. Nonparametric estimates of the relative risk (RR) of cataracts for the dose groups of liquidators are consistent with the estimates of ERR/Gy in the linear non-threshold (LNT) model. The determination of the dose threshold for cataracts according to the LNT model, in accordance with the recommendations of the ICRP, leads to estimates from 1.2 Gy to 13.3 Gy, depending on the presence or absence of cataract concomitant diseases in the liquidators.

Conclusions: At present, there are no epidemiological evidence for reducing the equivalent dose limit for the lens of the eye for occupational exposure in planned exposure situations at the level of 150 mSv per year, previously established by the recommendations of the ICRP in 2007 and the current Russian radiation safety standards NRB-99/2009.

Инсульт – это состояние острого нарушения мозгового кровообращения (ОНМК), продолжающееся более 24 часов, с соответствующей зоне поражения неврологической симптоматикой. Данное состояние может приводить к тяжёлой инвалидизации, стойким нарушениям двигательных, когнитивных функций ребёнка, и даже смерти. Самые распространенные причины инсультов у детей: аневризмы сосудов, сосудистые мальформации, тромбофилия, нейроинфекции, ревматологические и онкологические заболевания. По мере изучения патогенетических особенностей новой коронавирусной инфекции (COVID-19) были выявлены механизмы, способствующие развитию ОНМК, в том числе и у детей. Данные механизмы могут иметь значение и в развитии ОНМК при течении иных острых респираторных вирусных инфекций. Благодаря развитию и повышению доступности таких методов диагностики как магнитно-резонансная томография (МРТ), компьютерная томография (КТ), стало возможным выявлять инсульты на самых ранних стадиях. Комплексное обследование, включающее в себя данные клинического, лабораторного, инструментального обследования, нейровизуализационные методики, необходимо для верификации и патогенетического лечения ОНМК у детей и взрослых.

В данной статье затронуты проблемы ранней диагностики детского инсульта и особенности выбора лучевого метода исследования. Ниже представлен клинический случай пациента 11 лет, с генетически детерминированной склонностью к тромбозам, ранее перенесшего острое респираторное заболевание, с последствиями в виде ОНМК по ишемическому типу в бассейне левой средней мозговой артерии, а именно в зоне кровоснабжения передней ворсинчатой артерии.

Introduction: The leading protective mechanism of the lungs is the processes of deposition of inhaled substances and mucociliary clearance (MCC), the optimal method for studying which is dynamic radioaerosol scintigraphy. are not available on the market. The applicant in this regard for a number of characteristics is the radiopharmaceutical from albumin, produced in the Russian Federation under the brand name Macrotech (M). It is used for perfusion scintigraphy to verify primarily pulmonary embolism and its ability to study deposition of inhalants and MCC has not been studied.

Purpose: To study the aerodynamic properties of M dispersion and to determine the possibilities of its use for dynamic radioaerosol scintigraphy of the lungs in order to assess the processes of deposition of inhaled substances and MCC.

Material and methods: To study the aerodynamic properties of M, on which the assessment of the deposition of inhaled substances and MCC significantly depends, we studied the dispersion of its particles in different states, and studied them in shape and morphology. An ultrasonic inhaler TuR USI-50 (Germany) generated an aerosol from a suspension of M in distilled water. To study the dispersion in air, laser spectrometry was used using the Spraytec Malvern Instruments system (Great Britain). The protein content in the initial suspension and dispersible aerosol, collected in the form of a condensate, was determined using an Immulite 2000 XPi immunochemical analyzer (Siemens, USA).The shape and morphology of the particles were studied using scanning electron microscopy using.

Results: The study of the aerodynamic properties of the dispersion of M indicated that its particles are involved in the dynamics of the movement of the airflow and the flight of water particles generated by the inhaler. The dispersity of the aerosol generated from the suspension M averaged about 5 μm and did not significantly depend on the concentration of the radiopharmaceutical and did not depend on the studied dispersion intensity and airflow rate set using an inhaler. The morphology of M particles was characterized by a complex shape and roughness.

Conclusion: The aerodynamic characteristics of M are not optimal for studying the processes of deposition and MCC. However, a final verdict requires a direct assessment of the deposition of the inhaled radioaerosol generated from this preparation.