Individual Exposure Dose Research Articles

Concept of elaboration and operation of the united system for monitoring and recording of individual occupational exposure doses and the National Dose Registry of Ukraine

I n 2014–2018 within the frameworks of the “State social program for enhancement of the state of safety, occupational medicine and workplace environment for 2014-2018”, SE NRCRM had developed the methodological and organizational grounds of the United system for monitoring and registration of individual occupational exposure doses in Ukraine (the System), which were formulated in the respective Concept. The Concept includes the following chapters: the aim, the tasks, basic principles of the System elaboration, roadmaps and solutions, operational aspects of the functioning. The Concept envisages creation of the state (national) dose register, the coordination center, quality assurance program and present various aspects of the System functioning: interactions with data providers, data users, requirements to the scope and quality of the dosimetric data. Special attention is paid to possible risks for implementation, alternative options are considered. Elaboration and operation of the System that is based on the principles formulated in the Concept, will allow prompt accomplishment of the international standards in the area of ra-diation protection and safety. It would provide powerful tool for optimization of the levels of occupational exposure in Ukraine, and, ultimately, reduce negative impact of ionizing radiation on the population of our state Keywords: occupational exposure, radiation protection, doses, registry, occupational safety, dosimetric control. For citation: Chumak VV, Zimina OS, Bazyka DA. Concept of elaboration and operation of the united system for monitoring and recording of individual occupational exposure doses and the National Dose Registry of Ukraine. Journal of the National Academy of Medical Sciences of Ukraine. 2019;25(4):448–56.

Proposed Dose Constraints in the Duties of Radiation Workers at the Department of Nuclear Medicine.

This study aimed to set a dose constraint for certain duties of radiological technologists in the department of nuclear medicine. From 2013 to 2017, the 5 y radiation exposure data of employees performing PET-CT and γ-CAMERA of eight hospitals in Korea were measured individual exposure doses to estimate the frequency and set a representative dose of 75 and 95% from the low dose in the whole category is presented. The dose constraint was 5.5mSv for PET-CT, 4.5mSv for γ-CAMERA and 3.5mSv for Positron Emission Tomography (PET)-Computed Tomography(CT) and Gamma CAMERA (γ-CAMERA). Therefore, it would be appropriate to set a dose-limit value of ~5mSv corresponding to 75-80% of the individual exposure dose of radiological technologists in the department of nuclear medicine. The finding of this study may be used as reference data for setting future radiation dose limits.

ON JUSTIFICATION OF CHANGES IN THE RADON CONTENT RATIONING IN INDOOR AIR

The deadline for the development of the final draft of the new radiation safety standards RSS-2019, harmonized with international recommendations, including the regulation of radon content in the indoor air of residential and public buildings is expected to be finished in 2019. We estimated the possibility and expediency for replacement of the hygienic standard established in RSS -99/2009 with the reference level recommended by the International Basic Safety Standards of IAEA GSR Part 3 on the basis of data analysis results on radon content levels in indoor air of residential and public buildings on the territory of subjects of the Russian Federation. An analysis of the array of measurements results for radon content with a volume of 680,301 measurements taken during the period from 2001 to 2017 in the subjects of the Russian Federation collected as part of Unified State System for Control of Individual Exposure Doses and stored in the Federal database of exposure doses of citizens of the Russian Federation due to the natural and man-made background radiation was carried out. Absolute and relative estimates of the number of radon EEVA values exceeding 200, 150 and 120 Bq/m3 were obtained, both for individual regions and for the country as a whole. The results show that the reduction of hygienic standard of radon EEVA will increase the share of the non-compliant regulatory instruments of residential and public buildings up to 150 Bq/m3 almost in 2 times, up to 120 Bq/m3 almost in 3 times on average in Russia. We formulated a number of proposals aimed at harmonizing the Russian standards of radon content in indoor air with the IAEA recommendations taking into account the economic feasibility and while maintaining the possibility of monitoring compliance with the requirements of radiation population safety.

A STUDY OF LAYERED LENS CHANGE IN THE PROCESS OF CATARACT FORMATION IN PERSONS EXPOSED TO RADIATION AS A RESULT OF RADIATION ACCIDENTS IN THE SOUTHERN URALS

Up to now there is no clear understanding of health risk and type of dose dependence for the population chronically exposed within a range of low and average dose levels (to 1Gy). In this respect studies performed in cohorts with a sufficient number of persons can have a significant potential in providing necessary information. Objective: to study peculiarities of lens opacity in exposed persons at later time after chronic radiation exposure with due account for dose impact and nonradiation factors. The study includes patients from the URCRM registry of exposed population examined by an ophthalmologist in the period 2016-2018 (total 1,377 persons). The same technique of medical examination with photofixation of lens opacity was applied to all examined individuals. A case-control technique was used to conduct the study. Individual exposure doses to lens were calculated on the basis of TRDS-2016 for the first time within the framework of the present study. As a result of the performed study among persons exposed to long-term ionizing low-dose radiation we have determined an exposure dose impact on risk growth of opacity in the posterior capsule and lens nucleus. No reliable statistical dependence of lens change with an increasing exposure dose in anterior capsule and cortical layers as well as colour change of the lens nucleus was obtained. Belonging to different ethnical groups showed no impact on priority opacification development in any lens layers.

Evaluating the feasibility of a personal particle exposure monitor in outdoor and indoor microenvironments in Shanghai, China

ABSTRACTExisting particulate matter (PM) monitors have too low spatiotemporal resolution to properly characterize individual exposure doses. In order to support health impact assessment, it is essential to develop a better method to assess individual exposure by taking account of varied environments in which people spend their time. Compact light-scattering PM monitors can potentially fill this need. This study was conducted to evaluate feasibility of a low-cost PM monitor (Plantower PMS 7003) in indoor and roadside outdoor microenvironments compared to research-grade instruments in Shanghai, China. The monitors exhibited excellent performance with a high linear response and low bias values both in outdoor and indoor tests. The monitors also showed little confounding bias in low relative humidity environments. Taking into account the accessibility and portability of this monitor, the monitors were able to detect the dynamic nature of individual exposures and provide data and knowledge about human exposure assessments.

Human Biomonitoring as a Useful Approach to Health Risk Assessment Compared with Occupational Exposure Assessment of Insecticide Intake: Fundamental Study Focused on Local Populations and Occupational Fields

Human biomonitoring (HBM) is a technique to evaluate chemical exposure level by measuring the levels of chemicals or related substances such as their metabolites or adducts in biological samples (e.g., urine or blood). Compared with exposure assessment by an approach to estimate insecticide intake from diet or the environment, HBM can provide information more specific to an individual exposure dose and can reflect the exact body burden condition at the time of measurement. If the analytical sensitivities, completeness and cost-effectiveness of the method are improved further, HBM might be widely applicable to not only research fields such as epidemiological and occupational study but also routine analysis for effective prevention of the exposure of the human body to chemical substances. In this article, we provide an overview of HBM as a determination method for insecticide exposure markers in urine and its applications, and discuss future research perspectives in the field of environmental and occupational health.

ESTIMATION OF THE CUMULATIVE EXPOSURE FREQUENCY AND CUMULATIVE EFFECTIVE DOSE OF DIAGNOSTIC MEDICAL RADIATION IN THE KOREAN POPULATION FROM 2002 TO 2010.

Along with increase in the frequency and exposure dose from the diagnostic medical radiation procedures, the public's interest in radiation exposure has also been growing. In this study, in order to estimate the Cumulative Exposure Frequency and the cumulative effective dose of diagnostic medical radiation in the Korean population, we included 680 diagnostic medical radiation procedure codes of the Health Insurance Review & Assessment Service's health insurance medical expenses data and adopted the effective dose data from the 2008 report of the United Nations Scientific Committee on the Effects of Atomic Radiation. We combined the data of one million individuals in the national sample cohort database (2002-10) of the National Health Insurance Service. The results revealed that 93.2% (917 972) of the subjects were exposed to diagnostic medical radiation at least once in the past nine years, and the Cumulative Exposure Frequency was 17 286.4 per 1000 individuals with a cumulative effective dose of 5.7 (±17.8) mSv per person. Additionally, 93.1% (854 480) of the subjects had a cumulative effective dose less than 20 mSv, and 0.7% (6139) had a dose that exceeded 100 mSv (extreme), showing that the dosage level was mostly low. However, the number of individuals whose exposure exceeded 100 mSv/y increased 28-fold, from 18 in 2002 to 500 in 2010. In addition, the size of increase also grew each year, suggesting that cancer occurrence due to diagnostic medical radiation may have also increased. In order determine the causal relationship between cancer occurrence and diagnostic medical radiation and setup a guideline for exposure, it is necessary to monitor individual cumulative exposure doses nation-wide and follow up on heavily exposed individuals for an extended period of time.

Occupational and Public Exposure During Normal Operation of Radioactive Waste Disposal Facilities

This paper focuses on occupational and public exposure during operation of disposal facilities receiving liquid and solid radioactive waste of various classes and provides a comparative analysis of the relevant doses: actual and calculated at the design stage. Occupational and public exposure study presented in this paper covers normal operations of a radioactive waste disposal facility receiving waste. Results: Analysis of individual and collective occupational doses was performed based on data collected during operation of near-surface disposal facilities for short-lived intermediate-, lowand very low-level waste in France, as well as nearsurface disposal facilities for long-lived waste in Russia. Further analysis of occupational and public doses calculated at the design stage was completed covering a near-surface disposal facility in Belgium and deep disposal facilities in the United Kingdom and the Nizhne-Kansk rock massive (Russia). The results show that engineering and technical solutions enable almost complete elimination of internal occupational exposure, whereas external exposure doses would fall within the range of values typical for a basic nuclear facility. Conclusion: radioactive waste disposal facilities being developed, constructed and operated meet the safety requirements effective in the Russian Federation and consistent with relevant international recommendations. It has been found that individual occupational exposure doses commensurate with those received by personnel of similar facilities abroad. Furthermore, according to the forecasts, mean individual doses for personnel during radioactive waste disposal would be an order of magnitude lower than the dose limit of 20 mSv/year. As for the public exposure, during normal operation, potential impact is virtually impossible by delaminating boundaries of a nuclear facility sanitary protection zone inside which the disposal facility is located and can be solely attributed to the use of public roads during radioactive waste transportation to the disposal facility site.

Analysis of Individual Exposure Dose of Workers and Clinical Practice Students in Radiation Management Area

Analysis of Individual Exposure Dose of Workers and Clinical Practice Students in Radiation Management Area

Analysis of the eye examination results of 251 radiation medical workers

Objective To analyze the eye health conditions of the radiation medical workers in a hospital. Methods Two hundred and fifty-one radiation medical workers (radiation medical worker group) and two hundred and fifty non-radiation medical workers (control group) were asked about the medical history and examined.The uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), lens, ocular fundus were detected. The results and the annual external exposure dose were analyzed statistically. Results The average annual external exposure dose was (0.68±0.25)mSv. Among these 251 works, there were 249 works (99.2%) whose external exposure doses were lower than 1/10 dose limit of the national basic standards for radiation workers (20mSv/year). There was no one whose external exposure dose exceeded the standard limit. The eye manifestations with high incidence rate were ametropia, asthenopia, dry eye and lens abnormality including transparency reduction, increase of nucleus density and age-related cataract. No radiation cataract cases were detected. The incidence rate of asthenopia and dry eye in the radiation medical worker group was higher than that in the control group (χ2=6.964, P=0.008). The incidence rate of lens abnormality in the radiation medical worker group was also higher than that in control group(χ2=4.876, P=0.027). Conclusion The individual external exposure doses among radiation workers in this hospital are generally at a low level. The incidence rates of asthenopia, dry eye and lens abnormality in the radiation medical worker group are higher than that in the control group, which may be related to the environment and the nature of the work. Key words: Cataract, radiation; Dry eye; Asthenopia; Radiation medical worker; External radiation dose

Radiation-induced alternative transcription and splicing events and their applicability to practical biodosimetry.

Accurate assessment of the individual exposure dose based on easily accessible samples (e.g. blood) immediately following a radiological accident is crucial. We aimed at developing a robust transcription-based signature for biodosimetry from human peripheral blood mononuclear cells irradiated with different doses of X-rays (0.1 and 1.0 Gy) at a dose rate of 0.26 Gy/min. Genome-wide radiation-induced changes in mRNA expression were evaluated at both gene and exon level. Using exon-specific qRT-PCR, we confirmed that several biomarker genes are alternatively spliced or transcribed after irradiation and that different exons of these genes exhibit significantly different levels of induction. Moreover, a significant number of radiation-responsive genes were found to be genomic neighbors. Using three different classification models we found that gene and exon signatures performed equally well on dose prediction, as long as more than 10 features are included. Together, our results highlight the necessity of evaluating gene expression at the level of single exons for radiation biodosimetry in particular and transcriptional biomarker research in general. This approach is especially advisable for practical gene expression-based biodosimetry, for which primer- or probe-based techniques would be the method of choice.

Individual Daily Exposure To Black Carbon In Shanghai, China

Background and Aims: The vast majority of personal exposure to Black Carbon (BC) studies has taken place in developed countries. However, the population activity patterns in China are completely different from those in Western countries. We aimed to identify the activities and microenvironments that make the greatest concentration to individual daily exposure dose in Shanghai, China. Method: We recruited 51 graduate students in a university located in Shanghai, from December 2014 to March 2015. Personal BC was measured using aethalometers every 5 minutes. The Nork software was installed on a small handheld computer, to fill in executed activities and trips (such as studying, eating, transportation, sleeping etc.) and where time is spent each day. The accuracy of Nork software was also checked by consulting the GPS logs. The inhaled dose received by volunteers was determined for each microenvironment/activity. “Exposure (dose) intensity”, which is defined as the ratio of the daily exposure dose fraction to the daily time fraction, was calculated for each activity. Results: Overall mean BC exposure concentration was 5.3 ug/m3. High daily inhaled doses were also observed and were equal to 40.6 ug/day. An in-depth analysis of the exposure/dose experienced by participant revealed that indoor during general activity time made significant contributions to the students' daily dose, due to the time exposured to indoor was substantially longer than that of Western countries. Eating accounted for a lowest contribution of BC exposure. In particular, outdoor activities presented the highest BC dose intensity. Conclusion: Our study generated the prospective evidence that the microenvironment /activity contribution to BC personal exposure in China is very different from Western countries. These data contribute to the scientific literature on effects of air pollution for high exposure settings.

Experience of development and testing of a new model of an anthropomorphic radiodosimetric phantom of the human body ardf-10 "ROMAN"

In 2006-2010 by the commission of the Radiation and Nuclear Safety Authority in Finland applied scientific research and development of a new model of an anthropomorphic radiodosimetric phantom of the human body (the Phantom) were performed, after the development of the production technology and initial testing in 2010-2012 the first serial copy of the Phantom under the name ARDF-10 «ROMAN» was produced.The main application of the new model of the Phantom ARDF-10 «ROMAN»:- increase of the precision of calibration and implementation of the periodic monitoring of Whole body counters (WBC) equipment, standardization of measurement procedure for inter-laboratory comparisons of the incorporated activity.- metrological support of the development and implementation of new methods for human radiation spectrometry:identification of radionuclide content of incorporated activity in the human body;measurements of the activity of incorporated technogenic and natural radionuclides in the whole body and in the lungs;measurements of 90Sr content in the bone tissue.- study of the mechanisms of the intake, distribution, accumulation and excretion of the radionuclides in the human body, such as: - daughter products of 222Rn decay in the respiratory tract, 241Am, other transuranic elements; - isotopes of iodine in the thyroid gland; - radiopharmaceuticals administered to patients for diagnostic and medicinal purposes. - obtaining estimates of spatial-temporal distribution of individual internal exposure dose of a human.The result of the work of recent years has been the creation of hygienic safe standard sample of an anthropomorphic radiodosimetric phantom of the human body ARDF-10 «ROMAN», consisting of 4 anthropometric models of body parts, which are independent assembly units (head phantom, neck phantom, torso phantom, knee phantom). Phantom models are made from simulators of bone, soft (muscle) and lungs biological tissue. The Phantom contains 28 separate elements. To the first Phantom model simulators of organs and body parts with incorporated radionuclides 241Am, 210Pb, 239Pu and U-natural are included. Also the background phantom without radionuclides is produced. Calibration of WBC with planar detectors based on HPGe was performed, sample of persons exposed to the incorporated activity was studied.

THERAPY RELATED ACUTE LEUKAEMIA WITH MITOXANTRONE: 4 YEARS ON, WHAT IS THE RISK AND CAN IT BE LIMITED?

BackgroundTherapy related acute leukaemia (TRAL) is a concern for neurologists and patients when considering treatment with Mitoxantrone for Multiple Sclerosis (MS). In 2008 we performed a literature review to determine...

埼玉県南部地域における電子ポケット線量計を用いた個人外部被ばく線量の測定―東電福島第一原子力発電所事故後と事故前の比較―

埼玉県南部地域における電子ポケット線量計を用いた個人外部被ばく線量の測定―東電福島第一原子力発電所事故後と事故前の比較―

Evaluation of personal dose equivalent using optically stimulated luminescent dosemeters in Marumori after the Fukushima nuclear accident

The personal dose equivalent for 36 Marumori residents living in wooden houses was evaluated using optically stimulated luminescent dosemeters after the Fukushima nuclear accident. The cumulative doses to residents over 200 d from 1 September 2011 ranged from 536 to 1490 µSv. In each resident's house, the indoor and outdoor ambient dose equivalents were measured with an NaI scintillation survey meter. A linear relationship with a slope of 0.5 was found between them; however, the ratio of the indoor to the outdoor ambient dose equivalent varied from 0.36 to 1.0. A better linear relationship was observed between the personal dose equivalent and the indoor ambient dose equivalent compared with that between the personal dose equivalent and the outdoor ambient dose equivalent. These results indicate that the individual exposure dose depends on the indoor ambient dose equivalent rather than the outdoor ambient dose equivalent. These results should be very helpful in obtaining the countermeasures to reduce residents' exposure dose.

핵의학과 분배실 내의 공간선량률 측정

Even though the protective facility is well made with the development of medicine, the spatial dose within the radiation section could increase the exposure of the workers. The spatial dose is always present in distribution room within the Department of Nuclear Medicine, so the spatial dose of the interior distribution room is measured and analyzed for the prediction of the exposure dose. The spatial dose rate was in the distribution room of department of Nuclear Medicine, in , and distribution room. In addition, in case of distribution room, the yearly external exposure dose was when the nurse does IV in 1m in distance. It also showed that the spatial dose rate on the direction of right oblique showed higher than others by the standard of distribution window of distribution room. Therefore, the staying time of the workers should be short during distributing radiopharmaceuticals in the distribution room and the design of the distribution protection is necessary to reduce the exposure in the direction of right oblique of the protection. The utmost endeavors are required to reduce the worker`s individual exposure dose while doing IV.

Individual Radiation Exposure Dose Due to Support Activities at Safe Shelters in Fukushima Prefecture

Immediately after the accidents in the nuclear power stations in Fukushima on March 11, the Japanese Government ordered the evacuation of the residents within a 20-km radius from the station on March 12, and asked various institutions to monitor the contamination levels of the residents. Hirosaki University, which is located 355 km north of Fukushima City, decided to send support staff to Fukushima. This report summarizes the results of the exposure of 13 individual teams from March 15 to June 20. The support teams surveyed more than 5,000 people during this period. Almost all subjects had external contamination levels of less than 13 kcpm on Geiger-Müller (GM) survey meter, which is categorized as “no contamination level.” The 1st team showed the highest external exposure dose, but the 4th team onward showed no significant change. Subsequently, the internal radiation exposure was measured using a whole body counter that indicated undetectable levels in all staff members. Although the measured external radiation exposure dose cannot have serious biological effects on the health of an individual, a follow-up study of the residents in Fukushima and other regions where the radioactive material has spread will be required for a long time.

Ｃｏｍｐｕｔｅｄ Ｒａｄｉｏｇｒａｐｈｙ（ＣＲ）マンモグラフィにおける乳腺含有率の推定

Measurement of a percent glandular tissue composition (%GTC) is important in terms of the estimation of individual patient exposure dose and the prediction of malignancy, and thus a number of reports for estimating %GTC by use of a mammogram have been published. In this study, we propose a method for estimating individual %GTC by use of computed radiography (CR) mammograms. By employing breast-equivalent phantoms that are able to create breast phantom images with various combinations of fat and glandular tissue, as well as the thickness of whole breast, we determined a reference table for converting an each pixel value on CR mammography to the glandular tissue ratio. Therefore, the %GTC for individual breast was estimated by averaging glandular tissue ratio for a whole region. The clinical image data set that consisted of 49 CR mammograms were used for estimating %GTC. A paired comparison method for determining subjective ranking of the degree of breast density was employed in order to demonstrate the validity of our method. The results indicate that the average estimated %GTC was 35.0% (ranged from 12.0% to 67.0%) and they had a increased correlation with the ranking of those obtained by observer test. Therefore, it was suggested that our proposed method would be utilized for estimating the %GTC in objective manner.

ガラスバッジを用いた単純Ｘ線撮影における患者被ばく線量の測定

Radiography is used in medical practices based on the principles of justification and optimization. Patients' exposure doses should be kept as low as still allows for image quality that does not disturb the diagnostic processes. To optimize diagnostic radiological procedures, the international commission on radiological protection (ICRP) advocated the establishment of diagnosis reference levels (DRLs) in the new basic recommendation (Publication 103) in 2007 by stating that "The DRL should be expressed as a readily measurable patient-dose-related quantity for the specified procedure." In this context, a simple and standardized dosimetric method is needed to verify the adaptability of a radiation dose to the DRLs. As a measuring instrument that has good availability, high accuracy, and easy operability, we adopted the glass badge system, which has been used for individual exposure dose management. We evaluated the accuracy of the system as a tool of simplified dosimetry of diagnostic X-rays by comparing it to the standard dosimetry of an ionization chamber. In an energy range of 50 to 140 kV for X-ray exposure, the glass badge showed values within 7% of or closer to those measured by the standard ionization chamber. Moreover, the glass badge measurement was independent of the rectification modes of the X-ray tubes. In conclusion, glass badge measurement is feasible for verifying diagnostic X-ray doses in relation to DRLs and can be widely used in hospitals and clinics.