Radiation doses to the population of the Russian Federation in 2020

The article presents estimates of radiation doses of technogenic exposure to personnel and the public due to the normal operation of radiation facilities, exposure to the public due to natural sources and technogenically altered radiation environment, and medical exposure of patients. The doses values were obtained using the Unified System of Individual Dose Control of the Russian Federation citizens for 2020. The authors have analyzed the data contained in the forms of state statistical observation No. 1-DOZ, No. 2-DOZ, No. 3-DOZ and No. 4-DOZ for 2020 submitted by the organizations and territories, the state sanitary and epidemiological supervision of which was carried out by Rospotrebnadzor and Federal Medical Biological Agency of Russia. In the article also were used data obtained within the framework of Radiation-Hygiene Passportization. In 2020, 19 737 organizations dealing with technogenic sources of ionizing radiation submitted forms No. 1-DOZ with the information on the doses to personnel with a total number of 230 318 persons, of which 230 318 persons belonged to the personnel group A and 21 303 persons belonged to the personnel group B. For these groups, the doses were assessed based on results of individual dosimetric control. In 2020, according to Unified System of Individual Dose Control of the Russian Federation citizens data, the average individual annual effective dose of technogenic exposure to the personnel group A was 1.11 mSv, and for the personnel group B it was 0.63 mSv. In 2020, 6 cases of exceeding the average annual effective dose limit (20 mSv) for Group A personnel and 18 cases of exceeding the average annual effective dose limit (5 mSv) for Group B personnel were registered. The total number of X-ray and radiological diagnostic procedures performed in the Russian Federation in 2020 exceeded 275.4 million, or 1.83 procedures per a citizen. The average annual effective dose of medical radiation exposure per one resident of Russia in 2020 was 0.81 mSv, and per procedure – 0.44 mSv. The average annual effective dose of radiation to residents of the Russian Federation from natural sources, according to all measurements for the period from 2001 to 2020, was 3.36 mSv. More than 59% of this dose is associated with the inhalation of radon and its progenies. The average individual annual effective radiation dose to residents the Russian Federation subjects in 2020 ranged from 2.47 mSv (Kamchatka Krai) to 9.06 mSv (Altai Republic) with an average value for the Russian Federation of 4.18 mSv. For eight subjects of the Russian Federation, the average individual annual effective dose to public in 2020 exceeded 5 mSv: the Republics of Buryatia (5.31 mSv), Altai (9.06 mSv), Tyva (6.31 mSv), Magadan (5.07 mSv) and Irkutsk (6.13 mSv) regions, Stavropol (6.31 mSv) and Zabaykalsky (8.19 mSv) krai and the Evreiskaya Autonomous oblast (6.77 mSv).

Radon Monitoring by Alpha Track Detection Using Cn–85 Plastic Track

Radon sources can be found in external and internal radiation. Lead pencil (LP) is often used for drawing, sketching, etc. regardless of age nowadays. Paracetamol (PC) is commonly used around the world especially to treat fever, headache, menstrual pain, and common pain. Hence, the aim is to study the procedures for determining the radon gas comes out from different types of lead pencil and paracetamol. Eight and five samples were collected from different companies of lead pencil and paracetamol, respectively. The samples were measured using the sealed technique in cylindrical plastic containers with CN–85 detectors. After irradiation, the detectors were chemically etched using 2 N sodium hydroxide (NaOH) solution at a temperature of 70 ºC for 62 min. The alpha track density on the surface of detectors was measured using an optical microscope at a magnification of 100×. Tracks on detectors were counted using Image software. Radon concentration values including all samples in this study are within the limits of international which is 1000 Bq/m3. The concentration of radium in LP and PC samples are lower than those reported in previous study. The result of the uranium concentration of both samples is quite low compared with the allowed limit which is 11.7 ppm. Annual effective dose levels are all below the dose limit which is 10 mSv/y. Lastly, there was a linear relationship between radium activity and radon exhalation rate. Therefore, using LP and eating PC cause no danger to humans. All results showed in this study are within internationally permissible limits, and therefore not a threat to human health.

Preliminary results of a vaginal constraint for reducing G2 late vaginal complications after postoperative brachytherapy in endometrial cancer: a prospective analysis

Purpose To evaluate the preliminary results of the use of 68 Gy EQD2(α/β=3 Gy) as a dose limit to the lowest dose in the most exposed 2 cm3 of the vagina in order to reduce G2 late vaginal problems in postoperative endometrial carcinoma (EC). Methods From November 2016 to October 2019, 69 postoperative EC patients receiving vaginal brachytherapy (VBT) ± external beam radiotherapy (EBRT) were prospectively analyzed. The median EBRT dose was 45 Gy (range: 44–50.4 Gy), 1.8−2 Gy/day, 5 fractions(Fr)/week. VBT was administered with the following schedule: 1Fr of 7 Gy after EBRT and 2 daily Fr × 7.5 Gy in exclusive VBT. The dose was prescribed at 0.5 cm from the applicator surface with an active length of 2.5 cm; 56 patients were treated with vaginal cylinders (49–3.5 cm, 6–3 cm, and 1–2.5 cm) and 13 with the colpostat technique. The overall VBT dose was adjusted to meet the vaginal restriction of < 68 Gy EQD2(α/β=3 Gy) at 2 cm3. Late toxicity was prospectively assessed using RTOG scores for bladder and rectum, and the objective LENT-SOMA criteria for vagina. Results With a median follow-up of 31.0 months, no vaginal-cuff recurrences were found. Late toxicity: only 1G1(1.4%) rectal toxicity; 21G1(30.4%) and 3G2(4.3%) vaginal complications. Only one (1.4%) of 3 G2 manifested as vaginal shortening. Conclusions In postoperative EC patients treated with VBT, only one developed G2 vaginal stenosis with the use of 68 Gy EQD2(α/β=3 Gy) as a dose constraint. These preliminary results seem to indicate the value of this dose limit for reducing G2 vaginal stenosis. Nonetheless, these findings should be confirmed in a larger number of patients with longer follow-up.

Introduction to the Special LDLensRad Focus Issue

Recent epidemiological and experimental animal data, as well as reanalyses of data previously accumulated, indicate that the lens of the eye is more radiosensitive than was previously thought. This has resulted in a reduction of the occupational lens dose limit within the European Union countries, Japan and elsewhere. This Commentary introduces the work done by the LDLensRad Consortium contained within this Focus Issue, towards advancement of understanding of the mechanisms of low dose radiation cataract.

Study on Airborne Radionuclide Dispersion in Floating Nuclear Power Plant under the Loss-of-Coolant Accident

Floating nuclear power plant is a kind of nuclear power plant on a barge moored specifically in an area of the sea. In order to study the factors influencing airborne radionuclide dispersion induced by the loss-of-coolant accident in floating nuclear power plant, the floating nuclear power plant platform was taken as the research object, and the dispersion of airborne radionuclide under combined conditions of platform positions, wind directions, and break directions (north, south, west, and east) was simulated by the CFD (computational fluid dynamics) method. The results show that northern and southern breaks have less dangerous island area than western and eastern ones but have more platform dangerous area than the western and eastern ones. The risk of the southern break is the greatest, and that of the western break is the least. Rotating the floating nuclear power plant platform in a certain angle can reduce the damage of loss-of-coolant accident. The effects of the dose received by the personnel under the condition of the severe accident were evaluated based on previous research, showing that the inhalation effective dose and the effective dose of plume immersion exposure were less than the radiation dose limit of 0.25 Sv within two hours in the accident. The results of the study can provide reference for the design of floating nuclear power plant platform and the formulation of emergency plan.

Evaluasi Implementasi Etika Proteksi Radiasi Dalam Pemanfaatan Iptek Nuklir di Indonesia

The Indonesia Government Regulation No. 33 year 2007 concerning Safety of Ionizing Radiation and Safety of Radioactive Sources, which contains the ethical basis for radiation protection nuclear applications in Indonesia, is currently in the process of being revised. Radiation safety principles that will apply are recommended and set internationally from the previous IAEA BSS-115 recommendation to its revision with IAEA GSR Part 3. The principle is strengthened from three principles into ten principles stated in the IAEA Safety Fundamental 1 document by maintaining the previous three principles. These three principles are the principle of justification of decisions to change the radiation exposure situation, applying the dose limit value for individual protection from possible unfairness of the optimization process, and the optimization principle of protection and safety. The principles are compared with the prevailing ethical views and discussed to reduce the gaps in understanding in their application. This principle is discussed in all radiation exposure situations, namely planned exposure, emergency exposure, and existing exposure concluded that by adopting an applied ethical basis in the nuclear field that agreed upon at the global level after being adequately understood and accepted at the national level, regulations would be obtained that were fair, applicable, and respected when moderating conflicts of understanding and interests of the various parties involved in implementing them on radiation safety for the actual dose and potential dose towards effective regulatory while strengthening the regulatory (nuclear) culture in Indonesia.

The Effective Dose Analysis of Head CT-Scan on Adult Patients

This study was aimed to determine the difference of the effective dose from the clinical and theoretical on the head CT-Scan examination of adult patients and compare the data with the permitted dose limit from BAPETEN. The data collected at Haji Hospital Surabaya using MSCT Siemens Somatom Definition AS 64 Slice on five adult patients, aged between 28-67 years old. The step before the scanning process were adjusting the voltage (kV) and current values (mA) on the CT-Scan. The scanning duration for each patient was 4s and resulted in head images with CTDIvol and DLP values displayed on the monitor screen. The effective dose limit value for the head CT scan was 2.8 mSv, according to BAPETEN. The study results showed that the effective dose on head CT Scan examination was below the safe dose limit value, while the different fractions between the clinical and theoretical of Patient A, B, C, D, and E was 4.11%; 5.46%; 6.19%; 6.52%; and 5.42%, respectively.

Radiological Dose Assessment to Members of the Public Using Consumer Products Containing Naturally Occurring Radioactive Materials in Korea

Various products containing a small number of added radionuclides are commonly available for use worldwide. However, frequent use of such products puts the public at risk of radiation exposure. In this study, dose assessments to members of the public using consumer products containing naturally occurring radioactive materials (NORMs) were conducted for various usage scenarios to evaluate the external and internal exposure dose. Data for this study were obtained from previous literature and were statistically analyzed using Boxplot to determine the input data for assessment. A normalized value of activity concentration was used for dose evaluation. In addition to other external and internal dose calculation codes, analytical calculations were used to perform age-dependent. Based on analytical calculations, the highest total effective dose equivalent (TEDE) received from necklace products at the upper whiskers with an activity concentration of 4.21 Bq/g for 238U, 24.4 Bq/g for 232Th, and 0.55 Bq/g for 40K for various age groups is 2.03 mSv/y for 1 year old, 1.24 mSv/y for 10 years old and 1.11 mSv/y for adult, which are above the international commission for radiation protection (ICRP) recommended public dose limit of 1 mSv/y. Results of external and internal exposure dose obtained using Microshield code, IMBA code and Visual Monte Carlo (VMC) code are all below the recommended public dose limit of 1 mSv/y.

The Enhanced Naturally Occurring Radioactivity of Negative Ion Clothing and Attendant Risk

The study investigates commercially available negative ion clothing, and evaluations are made using gamma-ray spectroscopy and Geant4 Monte Carlo simulations. Observed to contain naturally occurring radioactive material (NORM), evaluations are made of the radiological risk arising from the use of these as items of everyday wear, undergarments in particular. Organ doses from these were simulated using the MIRD5 mathematical female phantom, with the incorporation of dose conversion factors (DCFs). At 175 ± 26, 1732 ± 247, and 207 ± 38 Bq, for 238U, 232Th, and 40K respectively, item code S05 was found to possess the greatest activity, while item code S07 was shown to have the least activity, at 2 ± 0.5 and 15 ± 2 Bq, and again for 238U and 232Th, respectively. Sample code S11 recorded least activity, at 29 ± 5 Bq, for 40K. Among the clothing items, sample item code S05 offered the greatest concentrations of Th, U and Zr, with percentage means of 1.23 ± 0.1, 0.045 ± 0.001, and 1.29 ± 0.1, respectively, giving rise to an annual effective dose of 1.57 mSv/y assuming a nominal wearing period of 24 h per day. Accordingly, the annual public dose limit of 1 mSv can be exceeded by their use.

Some aspects of radiation protection in radionuclide therapy departments

The paper presents the data that allow calculate the attenuation factors in lead, tungsten and concrete of various thicknesses or the thickness of shielding made of these materials for a given attenuation factor for the spectra of gamma radiation of 131I and 177Lu radionuclides. Using these data the effectiveness of the protection of supporting equipment (portable containers, shielded syringes, etc.) and the possible doses of external radiation of medical personnel in the radionuclide therapy department were calculated. It is shown that there are short-term operations in the production process when a radiation source (container with a capsule with activity, syringe with activity), being near the body of a medical worker, creates a significant dose rate. For this reason the annual individual dose of external exposure of a medical worker can approach or exceed 1/3 of the dose limit. Calculation of the attenuation of 131I gamma radiation by stationary shield showed that the thickness of walls and floors made of concrete 200 – 400 mm will ensure that the permissible values of the dose rates of gamma radiation in the air do not exceed at annual turnover of activity in the radionuclide therapy department of ~ 3.3 · 1012 Bq.