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1.
Phys Med ; 123: 103412, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38878629

RESUMO

The radiological examination frequency, i.e. the number of examinations performed annually, is necessary for estimating the collective effective dose of the population from medical exposures with ionizing radiation. Examination frequency surveys usually collect data from a limited number of radiological facilities participating in the survey. The collected data are then extrapolated to the existing radiological facilities in a country/region. Thus, the number of facilities and the specific facilities to participate, as well as, the extrapolation method used, are significant elements when designing the survey sample and methodology for examinations frequency assessments. This work attempted to simulate the situation when examination frequency data are collected from a limited number of facilities by investigating several "virtual sample" designs and two extrapolation methods. Comparisons between the calculated - by extrapolation - and the actual examination frequency in the country were made, for several scenarios and examination type data sets. The uncertainties were estimated and discussed thoroughly. The findings of this work highlighted the need for appropriate registry of the existing facilities in a country/region, the categorization of facilities considering the medical sector pattern in the country/region, the representativity and homogeneity of the samples used for a survey, as well as, the necessity for quality control of the collected examination frequency data. The results showed that when the aforementioned conditions were fulfilled, the examination frequency could be calculated with reasonable accuracy, based on data collected from a limited number of facilities. The paper also provides suggestions and tips for the collection and analysis of examination frequency data.


Assuntos
Doses de Radiação , Humanos , Incerteza , Exposição à Radiação/análise
2.
New Solut ; 34(2): 112-119, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38847133

RESUMO

The annual occupational doses for workers at the Ghana Research Reactor-1 facility were assessed for the period 2018-2021. The dose records of monitored staff were retrieved and analysis done for dose distribution and collective effective doses. Thermoluminiscent dosimeters were used to monitor the occupational exposures. The dosimeters were evaluated for the cumulative radiation dose levels using the Harshaw 6600 TLD reader system. Annual dose of 1.52 mSv/year was the maximum acquired by an individual. An annual average effective dose range of 0.20-1.36 mSv was determined for all workers. The annual total collective effective dose was established to be in the range of 0.40-10.08 man-Sv. The 20 mSv annual limit for occupational exposure was not exceeded for monitored workers. The assessment shows that the GHARR-1 facility, in terms of radiation health effects, is a favorable environment for workers since exposures are mostly below occupational exposure limit.


Assuntos
Exposição Ocupacional , Exposição à Radiação , Exposição Ocupacional/análise , Gana , Humanos , Exposição à Radiação/análise , Monitoramento de Radiação/métodos , Doses de Radiação , Reatores Nucleares , Dosimetria Termoluminescente
3.
Radiat Prot Dosimetry ; 200(9): 822-835, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38794881

RESUMO

Cosmic radiation exposure is one of the important health concerns for aircrews. In this work, we constructed a back propagation neural network model for the real-time and rapid assessment of cosmic radiation exposure to the public in aviation. The multi-dimensional dataset for this neural network was created from modeling the process of cosmic ray transportation in magnetic field by geomagnetic cutoff rigidity method and air shower simulation by a Monte Carlo based Geant4 code. The dataset was characterized by parameters including cosmic ray energy spectrum, Kp-index, coordinated universal time, altitude, latitude, and longitude. The effective dose and dose rate was finally converted from the particle fluxes at flight position by the neural network. This work shows a good agreement with other models from International Civil Aviation Organization. It is also illustrated that the effective dose rate by galactic cosmic ray is <10 µSv h-1 and the value during ground level enhancement (GLE) 42 is 4 ~ 10 times larger on the routes calculated in this work. In GLE 69, the effective dose rate reaches several mSv h-1 in the polar region. Based on this model, a real-time warning system is achieved.


Assuntos
Aviação , Radiação Cósmica , Método de Monte Carlo , Redes Neurais de Computação , Doses de Radiação , Monitoramento de Radiação , Humanos , Monitoramento de Radiação/métodos , Exposição Ocupacional/análise , Simulação por Computador , Exposição à Radiação/análise , Aeronaves
4.
Radiat Prot Dosimetry ; 200(7): 693-699, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38679858

RESUMO

This study presented a model applied for potential risk assessment in an interventional radiology setting. The model of potential risk assessment (MARP) consisted of the creation of a scale of indicators ranging from 0 to 5. The radiation levels were categorized according to gender, kind of procedure, value of kerma air product (Pka), and accumulated radiation dose (mGy). The MARP model was applied in 121 institutions over 8 y. A total of 201 656 patient radiation doses (Dose-area product and accumulated kerma) data were launched into the system over time, with an average of 22 406 doses per year. In the context of the workers (cardiologists, radiographers, and nurses) monitored during the MARP application, 8007 cases (with an average of 890 per year) of occupational radiation doses were recorded. This study showed a strategy for quality evaluation in fluoroscopy using a model with a compulsory information system for monitoring safety.


Assuntos
Exposição Ocupacional , Doses de Radiação , Humanos , Fluoroscopia/métodos , Medição de Risco/métodos , Exposição Ocupacional/análise , Exposição Ocupacional/prevenção & controle , Feminino , Masculino , Radiografia Intervencionista/efeitos adversos , Monitoramento de Radiação/métodos , Proteção Radiológica/normas , Proteção Radiológica/métodos , Radiologia Intervencionista/métodos , Radiologia Intervencionista/normas , Exposição à Radiação/análise
5.
Radiat Prot Dosimetry ; 200(7): 640-647, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38648184

RESUMO

According to UNSCEAR, cosmic radiation contributes to ~16% (0.39 mSv/y) of the total dose received by the public at sea level. The exposure to cosmic rays at a specific location is therefore a non-negligible parameter that contributes to the assessment of the overall public exposure to radiation. In this study, simulations were conducted with the Particle and Heavy Ion Transport code System, a Monte Carlo code, to determine the fluxes and effective dose due to cosmic rays received by the population of Douala. In minimum solar activity, the total effective dose considering the contribution of neutron, muon+, muon-, electron, positron and photon, was found to be 0.31 ± 0.02 mSv/y at the ground level. For maximum solar activity, it was found to be 0.27 ± 0.02 mSv/y at ground level. During maximum solar activity, galactic cosmic rays are reduced by solar flares and winds, resulting in an increase in the solar cosmic-ray component and a decrease in the galactic cosmic-ray component on Earth. This ultimately leads to a decrease in the total cosmic radiation on Earth. These results were found to be smaller than the UNSCEAR values, thus suggesting a good estimation for the population of Douala city located near the equatorial line. In fact, the cosmic radiation is more deflected at the equator than near the pole. Muons+ were found to be the main contributors to human exposure to cosmic radiation at ground level, with ~38% of the total effective dose due to cosmic exposure. However, electrons and positrons were found to be the less contributors to cosmic radiation exposure. As regards the obtained results, the population of Douala is not significantly exposed to cosmic radiation.


Assuntos
Radiação Cósmica , Íons Pesados , Método de Monte Carlo , Doses de Radiação , Monitoramento de Radiação , Humanos , Camarões , Monitoramento de Radiação/métodos , Atividade Solar , Simulação por Computador , Exposição à Radiação/análise
6.
Radiat Prot Dosimetry ; 200(7): 623-628, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38527175

RESUMO

Although boron neutron capture therapy (BNCT) causes minor damage to normal cells owing to the nuclear reactions induced by neutrons with major elements of tissues such as hydrogen and nitrogen, it is useful to estimate the accurate exposure dose for radiation protection. This study aims to estimate the contribution of internal exposure in radiation exposure dose for BNCT. The study was performed by referring to clinical studies at a reactor-based BNCT facility on the basis of computational dosimetry. Five irradiation regions of head and neck were selected for the estimation. The results suggest that external exposure occurred primarily in and around the irradiation field. Furthermore, during the exposure dose estimation in BNCT, internal exposure was found to be not negligible, implying that the irradiation regions in treatment planning must be considered for avoiding damage to certain critical organs that are susceptible to internal exposure.


Assuntos
Terapia por Captura de Nêutron de Boro , Terapia por Captura de Nêutron de Boro/métodos , Humanos , Dosagem Radioterapêutica , Nêutrons , Doses de Radiação , Radiometria/métodos , Proteção Radiológica/métodos , Exposição à Radiação/análise , Planejamento da Radioterapia Assistida por Computador/métodos , Método de Monte Carlo , Neoplasias de Cabeça e Pescoço/radioterapia , Imagens de Fantasmas , Simulação por Computador
7.
Radiat Prot Dosimetry ; 200(6): 580-587, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38486458

RESUMO

This study aimed to assess fetal radiation exposure in pregnant women undergoing computed tomography (CT) and rotational angiography (RA) examinations for the diagnosis of pelvic trauma. In addition, this study aimed to compare the dose distributions between the two examinations. Surface and average fetal doses were estimated during CT and RA examinations using a pregnant phantom model and real-time dosemeters. The pregnant model phantom was constructed using an anthropomorphic phantom, and a custom-made abdominal phantom was used to simulate pregnancy. The total average fetal dose received by pregnant women from both CT scans (plain, arterial and equilibrium phases) and a single RA examination was ~60 mGy. Because unnecessary repetition of radiographic examinations, such as CT or conventional 2D angiography can increase the radiation risk, the irradiation range should be limited, if necessary, to reduce overall radiation exposure.


Assuntos
Feto , Pelve , Imagens de Fantasmas , Doses de Radiação , Exposição à Radiação , Tomografia Computadorizada por Raios X , Humanos , Feminino , Gravidez , Exposição à Radiação/análise , Feto/efeitos da radiação , Feto/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Pelve/diagnóstico por imagem , Pelve/efeitos da radiação , Angiografia/métodos , Adulto
8.
Int J Environ Health Res ; 34(2): 1215-1226, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37165966

RESUMO

The variation of dissolved radon levels in water supplies remains of interest since radon ingested through drinking water can give considerable radiation to the lining of the stomach. This study aims to determine the radon concentration levels in bottled spring drinking water (BSW) brands commercially sold in Turkey using a radon gas monitor and to assess the internal radiation exposure caused by the ingestion and inhalation of radon. The activity concentrations of radon analyzed in 77 BSW brands varied from 7.1±0.8 to 28.7±2.7 mBq/L with an average of 15.7±5.1 mBq/L. The total annual effective dose was estimated to assess the radiological risk for three age groups in four different scenarios based on annual drinking water intake. All estimated dose values are well below the recommended reference dose of 100 µSv for drinking water. Therefore, radon gas in the investigated BSW samples poses no significant radiological risk to the public.


Assuntos
Água Potável , Exposição à Radiação , Monitoramento de Radiação , Radônio , Poluentes Radioativos da Água , Radônio/análise , Turquia , Poluentes Radioativos da Água/análise , Exposição à Radiação/análise
9.
J Radiol Prot ; 43(3)2023 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-37699376

RESUMO

The full-scale invasion of Ukraine by Russian military forces on 24 February 2022 put the radiological well-being of the people in Ukraine under unprecedented threat. Apart from the risks linked to operating nuclear power plants, there was substantial evidence of looting of facilities of all kinds, including those holding radioactive materials, as well as the scope for physical disturbance of radioactively contaminated areas and waste storage facilities. The actions of Russian military personnel invading Ukraine through the territory of the Chornobyl Exclusion Zone (the ChEZ) were of serious concern. Before its shutdown a few days after the beginning of the occupation, the automated radiation monitoring system of the ChEZ recorded sharp increases in the gamma-background in several areas which indicated some non-typical processes taking place on its territory. The State Nuclear Regulatory Inspectorate of Ukraine (SNRIU) and its technical support organisation, the Scientific and Technical Centre for Nuclear and Radiation Safety (SSTC NRS), as well as the rest of the professional nuclear community in Ukraine and worldwide, recognised the potential for movement of the radioactive contamination (reaching 101-104kBq m-2Cs-137 in the most of the territory) by the Russian military machinery and personnel to areas outside the ChEZ, creating locally contaminated spots along the routes taken by the invaders towards Kyiv. Certain apprehensions were caused by the inventory carried out after the liberation of the ChEZ which revealed the theft of calibration sources and radioactive samples from laboratories located in Chornobyl. As soon as this information became available to the public, it caused a wide response and anxiety, as a result of which SNRIU made a decision to conduct a radiation survey of the liberated territories in the Kyiv region. The survey was conducted between June and December 2022 by SSTC NRS specialists with the support of DSA. The scope of the survey was limited by available time and resources; however, the total route of the survey was about 840 km, and covered more than 50 settlements and a limited part of the ChEZ. The radiation survey combined the continuous gamma-dose rate measurements by the detectors installed in the laboratory vehicle and additional manual measurements at specified points. As a result of the radiation survey, no deterioration of the radiation situation was observed in the liberated territories. No contaminated objects, radiation sources, or other radioactive material removed from the ChEZ were found either. Measurements of the Cs-137 soil contamination in the ChEZ, although limited, corresponded to the results which had been obtained before the war. It can be concluded that in the surveyed territories, the direct impact on the public in the form of additional radioactive contamination removed from the ChEZ in February-March 2022 was negligible. The same applies to the radiation consequences of forest fires that occurred in the ChEZ during its occupation. However, due to the damage of the radiation monitoring system, explosive hazard, and destruction of transport infrastructure, the consequences of the occupation of the ChEZ by Russian troops will be long-term.


Assuntos
Acidente Nuclear de Chernobyl , Militares , Exposição à Radiação , Humanos , Radioisótopos de Césio/análise , Ucrânia , Ocupações , Exposição à Radiação/análise
10.
Health Phys ; 125(2): 102-108, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37022186

RESUMO

ABSTRACT: Healthcare workers may be exposed to ionizing radiation. Ionizing radiations are an important occupational risk factor for the potential damage they can cause to workers' health. Actually, the attention is focused on diseases caused by damage to radiosensitive organs. The aim of our study is to evaluate the methods used for the assessment of the impact of exposure to low-dose ionizing radiation in a population of healthcare workers (HCWs). The electronic database PubMed was searched by title, abstract, and medical subheadings (MeSH) terms. The extracted data were arranged into tables by dividing bibliographic reference, exposure, and statistical analysis information. The quality assessment was performed with the use of the Newcastle-Ottawa Quality Assessment Scale. The search strategy involved retrieving 15 studies (eight cohorts and seven cross-sectional studies). The univariate tests have been performed in 14 studies (93.3%), and Chi-square and T-test were the most commonly used. Multivariate tests have been performed in 11 studies (73.3%), and the most commonly performed were Logistic and Poisson Regressions. The most rated organ was the thyroid gland (six studies). The annual cumulative effective dose was the most used method to assess the dose rate (seven studies). Due to the characteristics of pathologies involved, a retrospective cohort study with an adequate control group and use of the annual cumulative effective dose to account for exposure could be useful features to obtain the best possible evidence. All the elements were found rarely in studies considered. The need is highlighted for more in-depth studies to investigate this topic.


Assuntos
Exposição Ocupacional , Exposição à Radiação , Humanos , Estudos Retrospectivos , Estudos Transversais , Exposição à Radiação/efeitos adversos , Exposição à Radiação/análise , Pessoal de Saúde , Radiação Ionizante , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise
11.
Radiat Prot Dosimetry ; 199(4): 318-324, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36588454

RESUMO

Occupational radiation doses of 602 medical workers from the departments of Radiology, Thoracic and cardiovascular surgery, Operating room, Nuclear medicine, Radiotherapy and cardiology were evaluated during 2017 to 2021 in three hospitals in Senegal. Each hospital was subdivided into various occupational groups. Whole-body doses Hp(10), local skin doses Hp(0.07) and annual collective dose Hp(10) were measured by OSL (optically stimulated luminescence) dosimetry. The occupational groups with the highest radiation exposures, ~0.185 mSv in 1 y, were in the field of nuclear medicine, radiology, cardiology, Thoracic and cardiovascular surgery and Operating room. All results of the measured annual effective dose were below the ICRP (International Commission on Radiological Protection) dose limits of 20 mSv/y, averaged over any 5-y period.


Assuntos
Medicina Nuclear , Exposição Ocupacional , Exposição à Radiação , Monitoramento de Radiação , Humanos , Doses de Radiação , Monitoramento de Radiação/métodos , Hospitais Comunitários , Senegal , Exposição à Radiação/análise , Exposição Ocupacional/análise
12.
Appl Radiat Isot ; 193: 110626, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36640699

RESUMO

Breast cancer is a common malignancy for females (25% of female cancers) and also has low incidence in males. It was estimated that 1% of all breast malignancies occur in males with mortality rate about 20%, with annual increase in incidence. Risk factors include age, family history, exposure to ionizing radiation and high estrogen and low of androgens hormones level. Diagnosis and screening are challenging due to limiting effectiveness of breast cancer screening. Therefore, patients may expose to ionizing radiation that may contribute in breast cancer incidence in males. In literature, limited studies were published regarding radiation exposure for males during mammography. The objective of this research is to quantify patient doses during male mammogram and to estimate the projected radiogenic risk during the procedure. In total, 42 male patients were undergone mammogram for breast cancer diagnosis during two consecutive years. The mean and range of patient age (years) is 45 (23-80). The mean and standard deviation (SD) of the peak tube potential and tube current time product are 28.64 ± 2. and 149 ± 35.1, respectively. The mean, and range of patients' entrance surface air kerma (ESAK, mGy) per single breast procedure was 5.3 (0.47-27.5). Male patient's received comparable radiation dose per mammogram compared to female procedures. With increasing incidence of male breast cancer, proper guidelines are necessary for the mammographic procedure are necessary to reduce unnecessary radiation doses and radiogenic risk.


Assuntos
Neoplasias da Mama , Exposição à Radiação , Humanos , Feminino , Masculino , Doses de Radiação , Mamografia/métodos , Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Exposição à Radiação/análise
13.
J Appl Clin Med Phys ; 23(8): e13713, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35775691

RESUMO

The most recent statement published by the International Commission on Radiological Protection describes a reduction in the maximum allowable occupational eye lens dose from 150 to 20 mSv/year (averaged over 5-year periods). Exposing the eye lens to radiation is a concern for nuclear medicine staff who handle radionuclide tracers with various levels of photon energy. This study aimed to define the optimal dosimeter and means of measuring the amount of exposure to which the eye lens is exposed during a routine nuclear medicine practice. A RANDO human phantom attached to Glass Badge and Luminess Badge for body or neck, DOSIRIS and VISION for eyes, and nanoDot for body, neck, and eyes was exposed to 99m Tc, 123 I, and 18 F radionuclides. Sealed syringe sources of each radionuclide were positioned 30 cm from the abdomen of the phantom. Estimated exposure based on measurement conditions (i.e., air kerma rate constants, conversion coefficient, distance, activity, and exposure time) was compared measured dose equivalent of each dosimeter. Differences in body, neck, and eye lens dosimeters were statistically analyzed. The 10-mm dose equivalent significantly differed between the Glass Badge and Luminess Badge for the neck, but these were almost equivalent at the body. The 0.07-mm dose equivalent for the nanoDot dosimeters was greatly overestimated compared to the estimated exposure of 99m Tc and 123 I radionuclides. Measured dose equivalents of exposure significantly differed between the body and eye lens dosimeters with respect to 18 F. Although accurately measuring radiation exposure to the eye lenses of nuclear medicine staff is conventionally monitored using dosimeters worn on the chest or abdomen, eye lens dosimeters that provide a 3-mm dose equivalent near the eye would be a more reliable means of assessing radiation doses in the mixed radiation environment of nuclear medicine.


Assuntos
Cristalino , Medicina Nuclear , Exposição Ocupacional , Exposição à Radiação , Proteção Radiológica , Humanos , Exposição Ocupacional/análise , Exposição Ocupacional/prevenção & controle , Doses de Radiação , Exposição à Radiação/análise , Exposição à Radiação/prevenção & controle , Proteção Radiológica/métodos , Radioisótopos
14.
Artigo em Inglês | MEDLINE | ID: mdl-34299788

RESUMO

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.


Assuntos
Exposição à Radiação , Monitoramento de Radiação , Radioatividade , Adulto , Humanos , Lactente , Método de Monte Carlo , Doses de Radiação , Exposição à Radiação/análise , Radioisótopos/análise , República da Coreia
15.
Sci Rep ; 11(1): 6162, 2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33731779

RESUMO

Emergency medical responders (EMRs) who treat victims during a radiation emergency are at risk of radiation exposure. In this study, the exposure dose to EMRs treating hypothetically contaminated patients was estimated using a Monte Carlo simulation, and the findings may be useful for educating EMRs and reducing their anxiety. The Monte Carlo simulation estimated radiation doses for adult computational phantoms based on radioactive contamination conditions and radiation dosages from previous studies. At contamination conditions below the typical upper limit of general Geiger-Müller survey meters, the radiation doses to EMRs were estimated to be less than 1 µSv per hour. In cases with greater contamination due to mishandling of an intense radioactive source (hundreds of GBq), the radiation doses to EMRs could reach approximately 100 mSv per hour. These results imply that a radiological accident with a highly radioactive source could expose EMR to significant radiation that exceeds their dose limit. Thus, authorities and other parties should ensure that EMRs receive appropriate education and training regarding measures that can be taken to protect themselves from the possibility of excessive radiation exposure. The results of this study may provide EMRs with information to take appropriate protective measures, although it is also important that they not hesitate to perform lifesaving measures because of concerns regarding radiation.


Assuntos
Socorristas , Doses de Radiação , Exposição à Radiação/análise , Monitoramento de Radiação , Proteção Radiológica , Humanos , Método de Monte Carlo , Imagens de Fantasmas , Monitoramento de Radiação/instrumentação , Monitoramento de Radiação/métodos , Liberação Nociva de Radioativos
16.
Health Phys ; 120(1): 105-111, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32897987

RESUMO

Cyclotrons used in nuclear medicine imaging accelerate protons, deuterons, and helium ions to bombard a target, which produces nuclear reactions that generate positron-emitting radionuclides. Secondary neutrons are nonuniformly emitted in these reactions and induce heterogeneous activation of the cyclotron components and concrete vault enclosure. This poses radioactive waste management complications when decommissioning a cyclotron facility, since the objective is to ensure that exposures are within regulatory limits and as low as reasonably achievable (ALARA). The McGovern Medical School in The University of Texas Health Science Center in Houston housed a Scanditronix MC40 cyclotron that produced short-lived radioisotopes for Positron Emission Tomography (PET) imaging from 1984 to 2001 until Tropical Storm Allison rendered it inoperable. The purpose of this study was to provide underrepresented Science, Technology, Engineering and Mathematics (STEM) students an ALARA experience with a practical problem encountered in the radiation safety profession. Gamma dose rate measurements were performed with both a Mirion InSpector 1000 spectrometer and Fluke 451P survey meter in the vault at locations identified as hotspots based on preliminary scoping surveys with the Ludlum model 44-9 detector. However, gamma spectra were measured with the spectrometer exclusively at hotspots along the west wall. Results indicated the maximum gamma dose rate of 129 ± 31 nSv h was about 2 times background near the central beam transport line of the now inoperable cyclotron. Furthermore, gamma emission peaks were identified in the spectra from trace amounts of Co and Eu in the vault's concrete walls.


Assuntos
Ciclotrons , Medicina Nuclear/educação , Proteção Radiológica , Humanos , Exposição Ocupacional/análise , Exposição à Radiação/análise , Monitoramento de Radiação , Radiometria , Faculdades de Medicina , Estudantes , Texas
17.
Z Med Phys ; 31(1): 58-64, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33309149

RESUMO

A multicenter study was conducted to assess the radiation exposure of relatives and caregivers of patients suffering from castration resistant prostate cancer with bone metastases and treated with Ra-223 dichloride in an outpatient setting. As Ra-223 and most of its progeny emit alpha particles, especially the internal exposure of persons in the patient's vicinity had to be evaluated. METHODS: The external radiation was measured in distances of 1 m and 2 m. Wipe-tests were taken in the patients' homes to identify significant contaminations and evaluated by liquid scintillation counting. Samples of saliva and sweat were taken and measured using gamma spectrometry. RESULTS: The external exposure from the patients measured 10-20min post injection (p. i.) was<0.080µSv/h in median in 1 m distance (range: below decision threshold (

Assuntos
Cuidadores , Família , Exposição à Radiação/análise , Rádio (Elemento)/efeitos adversos , Humanos , Exposição à Radiação/efeitos adversos
18.
Probl Radiac Med Radiobiol ; 25: 220-229, 2020 Dec.
Artigo em Inglês, Ucraniano | MEDLINE | ID: mdl-33361837

RESUMO

OBJECTIVE: To analyze and evaluate the available information to indoor radon concentration in the context of theimplementation of the radon action plan. OBJECT OF STUDY: indoor radon-222 in dwellings by area and corresponding radiation risks of the population. Measurements were performed using passive track radonometry. The exposure time of the radonometers is atleast 30 days during heating season. Radiation risk calculations were performed according to the dose coefficientsand mathematical models of the ICRP. RESULTS: It was found that for the whole country, reference level 300 Bq/m3 (radon gas) is exceeded in 16 % ofcases. It was found that geometric mean of radon gas levels was 120 Bq/m3 and varies from 35 to 265 Bq/m3 bydifferent area, namely the difference between radon levels in different territories of the country can be up to 7.5times. Variability of radon levels at the district level is also significant. It was found, radon activity concentrationdiffering by almost 10 times by districts with lognormal distribution and a geometric mean of 75 Bq/m3. The analy-sis of radiation risks of the population has established that estimated annual number of lung cancer deaths due toradon in Ukraine is almost 8,900 cases; and а direct economic loss for the country are estimated at more than $450 million a year. CONCLUSIONS: Surveys of radon levels demonstrated significant variation in radon concentrations between different regions. For the whole country, reference level (300 Bq/m3) is exceeded on above 16 % of the dwellings, butpercentage of exceeding varies from 0.1 to 43.0 % by different area. Information on indoor radon concentrationsin almost a third of the country is non-available. For an effective implementation of the Action plan, it makes sense to introduce radon risk mapping.


Assuntos
Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Neoplasias Pulmonares/epidemiologia , Exposição à Radiação/análise , Radônio/análise , Poluentes Radioativos do Ar/toxicidade , Carga Corporal (Radioterapia) , Humanos , Neoplasias Pulmonares/economia , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/patologia , Doses de Radiação , Monitoramento de Radiação/métodos , Radônio/toxicidade , Fatores de Risco , Estações do Ano , Ucrânia/epidemiologia
19.
Probl Radiac Med Radiobiol ; 25: 204-219, 2020 Dec.
Artigo em Inglês, Ucraniano | MEDLINE | ID: mdl-33361836

RESUMO

OBJECTIVE: Basing on the integrated assessment to conduct a comparative statistical analysis as of 2016 of thedemographic state of the areas of Ukraine that are recognized as those with the most intensive radiological con-tamination due to the Chornobyl NPP accident.Study object. The population of the regions of Ukraine with the most intensive radiological contamination due tothe Chornobyl NPP accident and the population of Ukraine as a whole (control). MATERIALS AND METHODS: The data of the State Statistics Service of Ukraine and its regional offices were used asinformation base in this study. Integrated assessment of the demographic situation in a oblast was conducted basedon the calculations of the territorial indices and multidimensional average variable on each region. Demographic,mathematical-statistical, graphic, software-technological methods were used in this study. RESULTS AND CONCLUSION: Radiologically contaminated regions of Ukraine differ significantly: both by the number ofpopulation (from 5800 people in the Poliske region to 105100 people in the Sarny region), and by the variability inthemedical and demographic indicators; bothone from another and compared to data for the country.The results of the calculations of 10 medical and demographic («positive¼ and «negative¼) territorial indices andmultidimensional average variable (P) as integrative assessment of the demographic state have revealed that thebest indicators of the demographic situation in 2016 were in Rokytne (P = 1.249) and Sarny (P = 1.112) regions ofthe Rivne oblast, while the worse indicators were in Kozelets (P = 0.363) and Ripky regions of the Chernihiv oblast.The demographic situation of the Olevsk region of the Zhytomyr oblast (P = 0.947)was the closest to the nationalaverage one. Poliske, Narodychi, Ovruch, Ivankiv and Korosten regions take intermediate position as comparedto theregions of Rivne and Chernihiv oblasts (P = 0.618-0.742).


Assuntos
Acidente Nuclear de Chernobyl , Contaminação Radioativa de Alimentos/análise , Exposição à Radiação/análise , Monitoramento de Radiação/métodos , Carga Corporal (Radioterapia) , Radioisótopos de Césio/análise , Raios gama , Humanos , Doses de Radiação , População Rural , Poluentes Radioativos do Solo/análise , Fatores de Tempo , Ucrânia , Contagem Corporal Total
20.
Radiat Environ Biophys ; 59(4): 643-650, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32728872

RESUMO

The dose limit for the skin of the hand is typically converted to a surface of 1 cm2, which means that one needs to measure point doses in different places on the hand. However, the commonly used method of measuring doses on the hand, i.e., using a dosimetric ring including one or several thermoluminescent detectors worn at the base of a finger, is not adequate for manual procedures such as labeling or radiopharmaceutical injection. Consequently, the purpose of this study was to create and conduct a series of computer simulations that, by recreating the actual working conditions, would provide information on the values of ionizing radiation doses received by the most exposed parts of the hands of employees of radiopharmaceutical production facilities, as well as those of nurses during the injection of radiopharmaceuticals. The simulations were carried out using Monte Carlo radiation transport calculations. The Hp(0.07) personal dose equivalent values obtained for the fingertips of the index and middle fingers of nursing staff and chemists were within the range limited by the minimum and maximum Hp(0.07) values obtained as a result of dosimetric measurements carried out in diagnostic and production centers. Only in the case of the nurse's fingertip, the simulated value of Hp(0.07 slightly exceeded the measured maximum Hp(0.07) value. The comparison of measured and simulated dose values showed that the largest differences in Hp(0.07) values occurred at the thumb tip, and for ring finger and middle finger of some of the nurses investigated.


Assuntos
Fluordesoxiglucose F18 , Exposição Ocupacional/análise , Doses de Radiação , Exposição à Radiação/análise , Radiação Ionizante , Compostos Radiofarmacêuticos , Algoritmos , Simulação por Computador , Feminino , Mãos , Humanos , Método de Monte Carlo , Enfermeiras e Enfermeiros , Tomografia por Emissão de Pósitrons , Pele
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