The article is devoted to development prospects of nuclear medicine in the Russian Federation. One of the first to provide nuclear medicine in Soviet Union was A.I. Burnasyan. He headed the 3d Directorate General of Ministry of Health (the FMBA of Russia at present). The Institute of Biophysics and the Institute of Medical Radiology (Obninsk), was established in the 50s – 60s of the 20th century, laid the foundation for nuclear medicine and developed it. With their efforts, nuclear medicine in USSR has become the world leader. However, in the 1980s – 1990s, there was a serious lag in this area due to radiophobia that arose after the Chernobyl accident, as well as the collapse of the USSR and the severe economic crisis, overcoming which in the beginning of the 21st century made it possible to pay considerable attention to nuclear medicine. Today the FMBA of Russia leads in the development and application of nuclear medicine technology. In the departments of the FMBA of Russia – the Siberian Research and Clinical Center (Krasnoyarsk) and Northern Medical Clinical Center N.A. Semashko (Arkhangelsk) – carries out high-tech diagnostics and treatment of cancer, neurological and cardiac diseases. Currently, in Dimitrovgrad city, the creation of the Federal High-Tech Center for Medical Radiology of the FMBA of Russia (FHCMR, FMBA of Russia) under the state program “Establishment of Federal Centers of Medical Radiological Technologies” is being completed. FHCMR, FMBA of Russia will provide high-tech medical care to the assigned contingent of the FMBA of Russia and the adult population of the Central, Volga, North-West federal districts. In the article noted the need for training specialists in the nuclear medicine. Training of specialists is already being conducted at the Training and Education Center of the Federal Siberian Research and Clinical Center of the FMBA of Russia. An important aspect of the introduction of nuclear medicine technologies and the operation of such centers are issues of legal regulation. The article pays attention to the licensing of nuclear medicine objects in accordance with the requirements of the Federal Law No. 170-FZ of November 21, 1995 “On the Use of Atomic Energy”. The tasks that need to be addressed for the development of nuclear medicine technologies are formulated, including through the implementation of the public-private partnership mechanism, as well as by expanding international cooperation with the EAEU member states.

The current paper is devoted to the outcomes of the 66-th UNSCEAR Session which took place in Vienna during 10–14 June 2018. Within the framework of the meetings of the Working Group and subgroups the documents on the following projects were discussed: R.733. Evaluation of selected health effects and inference of risk due to radiation exposure. R.734. Evaluation of medical exposures to ionizing radiation. R.735. Evaluation of occupational exposures to ionizing radiation. R.736. Lung cancer from exposure to radon. R.737. Biological mechanisms relevant for the inference of cancer risks from low-dose radiation. R.738. Levels and effects of radiation exposure due to the accident at the Fukushima Daiichi nuclear power station: implications of information published since the 2013 UNSCEAR report. R.739. Second primary cancer after radiotherapy. R.740. Epidemiological studies of radiation and cancer. The Committee also discussed: the future research program; report to the UN General Assembly; implementation of a strategy plan to improve collection, analysis and dissemination of data on radiation exposure; public outreach activity including the strategy for the period 2020–2024.

Current paper is devoted to the main outcomes of the 64th UNSCEAR Session which took place in Vienna during 10 – 14 June 2018. Within the framework of the meetings of the working group and subgroups the documents on the following projects were discussed: - Biological mechanisms influencing health effects from low-dose radiation exposure. - Developments since the 2013 UNSCEAR report on the levels and effects of radiation exposure due to the nuclear accident following the great East-Japan earthquake and tsunami: review of 2016 scientific literature including an evaluation of thyroid cancer data in regions affected by the Chernobyl accident. - Exposure of patients to ionizing radiation. - Exposure of workers to ionizing radiation. - Selected evaluations of health effects and of risk inference due to radiation exposure. - Lung cancer from exposure to radon and to penetrating radiation. In the course of the discussion, some organizational issues such as preparation of UNSCEAR publications, feasibility of establishing standing working groups, public outreach activities, future research program, report to the General Assembly etc., were considered.

Purpose: A synthetic study of published data on the growth and development of laboratory rats (albino random-bred, Wistar and Long–Evans) depending on the period of their breeding since 1906 was carried out. Material and methods: Data for the dynamics of growth and age periods of rats were used for calculations and general analysis. Results: Acceleration in terms of age–weight indices for strain animals was found: in conditions of complete diets ad libitum the contemporary rats grew several times faster than the bred ones of 1906–1932. For random-bred rats only the tendency to acceleration was obtained. For more than a century, the Wistar males showed an inverse linear correlation between the breeding year and the age (in weeks) at the of the onset of puberty period (according to the Spearman test: r = –0.952; p = 0.00026; Pearson’s criterion: r = –0.950, p = 0.0003). There was also a direct correlation between the body mass of rats at the time of puberty onset and the year of their breeding (according to the Spearman test: r = 0.975; p = 0.005; Pearson criterion: r = 0.927; p = 0.023). The possible reasons for the acceleration of laboratory growth of rats, which are unlikely to be analogous to the factors presumably causing the known ‘growth acceleration’ in humans (changes in natural and artificial lighting, the effect of heterosis, improvement of socio-hygienic conditions, the growth of information flow, warming of the climate, change in the geomagnetic or radiation background, etc.) were discussed. Apparently, in addition to the probability of special and/or subconscious selection during century, the stimulation of rat acceleration may be explained by the ‘increase in living space and resources’ due to improved standards for keeping animals in the modern period (fewer animals in the cage or even an individual cage). In random-bred animals such standards can be apply for economic reasons to a lesser extent. Conclusions: It is concluded that the physiological, anatomical, possibly behavioral and other standards and patterns for strain rats, including, possibly, its radiosensitivity, published even 30 years ago, and especially more than 50 years ago, should be cautiously transferred to the animals grown under present-day conditions.

Purpose: To estimate the impact of 3H-thymidine on DNA double strand breaks (DSBs) induction in cultured human mesenchymal stem cells (MSC). Material and methods: Isolation and cultivation of human bone marrow MSC was carried out according to a standard procedure. A sterile solution of 3H-thymidine with different specific radioactivity was added to the cell culture and incubated under the conditions of the CO2 incubator for 24 hours. The specific radioactivity of 3H-thymidine in the incubation medium was 50–1600 kBq/ml. To evaluate quantitatively the DSBs, an immunocytochemical analysis of the DSB marker – γH2AX foci histone was used. Additionally, the proportion of dividing cells was estimated using an immunocytochemical analysis of the cell proliferation marker, the Ki67 protein. Results: It was shown that 24 h incubation of human MSC in a culture medium results in a dose-dependent increase in γH2AX foci. There is a linear increase in the foci γH2AX in the range of 50–400 kBq/ml, after which the relative quantitative yield of foci per unit of specific radioactivity begins to decrease. In general, the dose-effect relationship is approximated by the quadratic function y = 3.13 + 50.80x – 12.38x2 (R2 = 0.99), where y is the number of foci γH2AX in the cell nucleus, and x is the specific radioactivity in 1000 kBq/ml. It was found that incubation of human MSC in a culture medium containing 800 and 1600 kBq/ml of 3H-thymidine resulted in a statistically significant decrease in the cells proliferative activity compared to the control of ~1.25 and 1.41 respectively. The peculiar biological limitation of tritium accumulation in the cell nucleus explains well the nonlinear character of the dependence of the formation of DSBs on the specific radioactivity of 3H-thymidine in the culture medium observed in our study. Conclusion: Quantitative analysis of γH2AX foci has proved to be a highly reproducible and highly sensitive method for evaluating the induction of DSBs in living cells under the action of 3H-thymidine. An analysis of the foci of γH2AX will be useful for accurate estimating the quantitative yield of DBS in living cells per dose of 3H-thymidine β-radiation. To do this, it is necessary to make a correct calculation of the doses received by the cells taking into account the microdistribution of 3H-thymidine in the cell volume and its accumulation in the DNA of living cells.

Purpose: To obtain data of radiation survey in workplaces of the personnel of the Priargun Production Mountain Chemical Association (OJSC PPMCA), who work at the premises of the ground facilities. Material and methods: In the course of the radiation survey. Integral track methods were used to measure radon activity concentration by REI-1 track cameras of the TRACK-REI-1M kit. To assess the activity balance factor between radon and its radionuclide progenies, short term measurements of radon activity concentration (AC) and effective equilibrium concentration (EEC) of radon by handle radiometers of radon and its progenies. Gamma dose rate was measured by handle dosimeters. Results: Annual AC, EEC and effective dose due to radon and external gamma exposures in workplaces at the ground facilities of OJSC PPMCA have been obtained. Total number of the inspected workshops is 138, including 121 workshops occupied by the A group personnel, and 17 – by the B group personnel. Conclusions: It was shown that annual doses 20 mSv could be exceeded for the A group personnel who work at three workshops shaft 8K of the mine-2, one workshop of building 630A of the Hydro-metallurgical Plant and one workshop of shaft 5 B of G mine. In the workshops of the B group personnel, 5 mSv annual effective doses can be exceeded 2 and more times at the premises of canteen number 18 and administrative domestic building of mine-2.

Purpose: To share the experience in regulation of radiation safety and protection of workers involved in management of the spent nuclear fuel (SNF) and radioactive waste (RW), as well as radiation protection of the population and environment in the vicinity of sites for temporary storage at Andreeva Bay on the Kola Peninsula. Material and methods: Spent fuel from Russian nuclear powered submarines has been stored at shore based facilities for more than 20 years, notably at Andreeva Bay. The storage facilities were for some years poorly maintained and a significant fraction of the fuel that is still in store at the site wais damaged. Over the last years, hugemuch work has been done to improve the technical infrastructure and prepare for removal of the SNF from the temporary stores, management of existing RW. Results: This paper presents progress with projects of the FMBA of Russia and NRPA cooperation for regulation of radiation safety and protection. During the researches, the following issues were addressed: radiological threat assessment to identify the priority directions of regulation; detailed analysis of the radiation situation on sites, at the territories and nearby the sites; radiation control and monitoring of the environmental conditions; development of the computer maps and geo-information system; emergency preparedness and response; improvement of radiation safety culture; etc. Based on the received results of monitoring and assessment of the current risks, site-specific regulatory documents have been developed for the bodies and institutions under the FMBA of Russia involved in the activities to control the facility. Those documents include the requirements for: radiation protection of workers and population; personal dose monitoring; the RW management including the very low level RW; implementation of the environmental monitoring; radiation monitoring nearby the Andreeva Bay SevRAO facility; and remediation of the sites as remediation criteria and regulations. The next stage of work is to carry out the regulation of large-scale removal of SNF during 2017–2021 and its subsequent transfer to Mayak PA, and operations to bring the infrastructure of the site into the hsafe conditions, i.e., ecological remediation of the site – by 2025. Lessons learnt from this work are being used in support of improved international recommendations and guidance on how to address legacy issues. Conclusion: The experience accumulated during regulation of the remediation process of the former Naval Coastal Technical Bases, has helped to identify new relevant areas of improvement of the regulatory supervision at nuclear legacy sites. The study of potential hazard of radiation exposure to the personnel during technological operations of SNF and RW management is very important issue. In this light, the regulator in cooperation of the operator should develop some effective and efficient activities for dose monitoring. When dealing with the protection of the population and environment, a methodology of comprehensive radiation and chemical monitoring should be developed and models of radiation and chemical risks should be improved taking into account features of contamination of the site under remediation. An important link of the social focus of the regulator and the operator is to improve strategies of public communications near legacy sites under remediation.