scispace - formally typeset
Search or ask a question

Showing papers in "Radiation Protection Dosimetry in 2012"


Journal ArticleDOI
TL;DR: This paper exploits the possibility of using commercial software for thermoluminescence and optically stimulated luminescence curve deconvolution analysis to both experimental and reference glow curves resulted from the GLOw Curve ANalysis INtercomparison project.
Abstract: This paper exploits the possibility of using commercial software for thermoluminescence and optically stimulated luminescence curve deconvolution analysis. The widely used software package Microsoft Excel, with the Solver utility has been used to perform deconvolution analysis to both experimental and reference glow curves resulted from the GLOw Curve ANalysis INtercomparison project. The simple interface of this programme combined with the powerful Solver utility, allows the analysis of complex stimulated luminescence curves into their components and the evaluation of the associated luminescence parameters.

178 citations


Journal ArticleDOI

147 citations


Journal ArticleDOI
F. Gharbi1, M. Oueslati1, W. Abdelli1, M. Samaali1, M. Ben Tekaya1 
TL;DR: Results indicate no significant radiological hazards arise from using such materials in building construction.
Abstract: Building materials can expose public and workers to radiation because of their content of radium, thorium and potassium isotopes. This is why it is very important from the radiological point of view to survey the natural radioactivity content of commonly used building materials in any country. This work consists of the measurement of (226)Ra, (232)Th and (40)K activity concentrations in a variety of commonly used building materials in Tunisia and on the estimation of their radiological hazard. The maximum value of radium equivalent for the studied materials was equal to 169 Bq kg(-1) and corresponds to the clay brick, which is lower than the recommended value of 370 Bq kg(-1). In this work, several radiological indexes were calculated and were found to be under their highest permitted limit.

131 citations



Journal ArticleDOI
TL;DR: Concentrations of primordial radionuclides in common construction materials collected from the south-west coastal region of India were determined using a high-purity germanium gamma-ray spectrometer to assess any radiological contamination due to construction materials in future.
Abstract: Concentrations of primordial radionuclides in common construction materials collected from the south-west coastal region of India were determined using a high-purity germanium gamma-ray spectrometer. Average specific activities (Bq kg(-1)) for (238)U((226)Ra) in cement, brick, soil and stone samples were obtained as 54 ± 13, 21 ± 4, 50 ± 12 and 46 ± 8, respectively. Respective values of (232)Th were obtained as 65 ± 10, 21 ± 3, 58 ± 10 and 57 ± 12. Concentrations of (40)K radionuclide in cement, brick, soil and stone samples were found to be 440 ± 91, 290 ± 20, 380 ± 61 and 432 ± 64, respectively. To evaluate the radiological hazards, radium equivalent activity, various hazard indices, absorbed dose rate and annual effective dose have been calculated, and compared with the literature values. Obtained data could be used as reference information to assess any radiological contamination due to construction materials in future.

80 citations



Journal ArticleDOI
TL;DR: RENEB will provide a mechanism for quick, efficient and reliable support within the European radiation emergency management and concurrently contribute to increased safety in the field of radiation protection.
Abstract: In Europe, a network for biological dosimetry has been created to strengthen the emergency preparedness and response capabilities in case of a large-scale nuclear accident or radiological emergency. Through the RENEB (Realising the European Network of Biodosimetry) project, 23 experienced laboratories from 16 European countries will establish a sustainable network for rapid, comprehensive and standardised biodosimetry provision that would be urgently required in an emergency situation on European ground. The foundation of the network is formed by five main pillars: (1) the ad hoc operational basis, (2) a basis of future developments, (3) an effective quality-management system, (4) arrangements to guarantee long-term sustainability and (5) awareness of the existence of RENEB. RENEB will thus provide a mechanism for quick, efficient and reliable support within the European radiation emergency management. The scientific basis of RENEB will concurrently contribute to increased safety in the field of radiation protection.

64 citations


Journal ArticleDOI
TL;DR: There is a need for a focus on education and awareness by all levels of government, and in partnership with key stakeholders, to encourage Canadians to take action to reduce the risk from indoor radon exposure.
Abstract: Exposure to indoor radon has been determined to be the second leading cause of lung cancer after tobacco smoking. Canadian population risk of radon induced lung cancer was assessed in 2005 with the radon distribution characteristics determined from a radon survey carried out in the late 1970s in 19 cities. In that survey, a grab sampling method was used to measure radon levels. The observed radon concentration in 14,000 Canadian homes surveyed followed a log-normal distribution with a geometric mean (GM) of 11.2 Bq m(-3) and a geometric standard deviation (GSD) of 3.9. Based on the information from that survey, it was estimated that ∼10 % of lung cancers in Canada resulted from indoor radon exposure. To gain a better understanding of radon concentrations in homes across the country, a national residential radon survey was launched in April 2009. In the recent survey, long-term (3 month or longer) indoor radon measurements were made in roughly 14 000 homes in 121 health regions across Canada. The observed radon concentrations follow, as expected, a log-normal distribution with a GM of 41.9 Bq m(-3) and a GSD of 2.8. Based on the more accurate radon distribution characteristics obtained from the recent cross-Canada radon survey, a re-assessment of Canadian population risk for radon induced lung cancer was undertaken. The theoretical estimates show that 16 % of lung cancer deaths among Canadians are attributable to indoor radon exposure. These results strongly suggest the ongoing need for the Canadian National Radon Program. In particular, there is a need for a focus on education and awareness by all levels of government, and in partnership with key stakeholders, to encourage Canadians to take action to reduce the risk from indoor radon exposure.

64 citations


Journal ArticleDOI
TL;DR: An analysis of the thyroid cancer incidence in the population of the most contaminated territories of Bryansk, Kaluga, Oryol and Tula oblasts affected by the Chernobyl accident found that no radiation risks of a thyroid cancer among people of 18 y of age at exposure and older were found.
Abstract: This study presents an analysis of the thyroid cancer incidence in the population of the most contaminated territories of Bryansk, Kaluga, Oryol and Tula oblasts affected by the Chernobyl accident. The follow-up period is 1991-2008, and the cohort size is 309 130 people. For that period 978 thyroid cancer cases were detected. The excess relative risk per 1 Gy (ERR/Gy) is found to be statistically significant for children and adolescents (0-17 y of age) at the time of the Chernobyl accident (ERR/Gy=3.22; 95 % confidence interval (1.56; 5.81). In boys, the ERR/Gy was higher than in girls -6.54 and 2.24, respectively. A statistically significant decrease in ERR/Gy with time since exposure, by a factor of 0.37 per 10 y, was observed for the whole cohort and for boys separately, but not for girls. No radiation risks of a thyroid cancer among people of 18 y of age at exposure and older were found.

63 citations


Journal ArticleDOI
TL;DR: The conversion coefficients from air kerma to H(p)(3) for the cylinder phantom are supplied for X- and gamma radiation qualities defined in ISO 4037.
Abstract: The International Organization for Standardization (ISO) has issued a standard series on photon reference radiation qualities (ISO 4037). In this series, no conversion coefficients are contained for the quantity personal dose equivalent at a 3 mm depth, H(p)(3). In the past, for this quantity, a slab phantom was recommended as a calibration phantom; however, a cylinder phantom much better approximates the shape of a human head than a slab phantom. Therefore, in this work, the conversion coefficients from air kerma to H(p)(3) for the cylinder phantom are supplied for X- and gamma radiation qualities defined in ISO 4037.

61 citations


Journal ArticleDOI
TL;DR: The methods used to estimate typical organ-specific doses delivered by CT scans to children are described and an organ dose database from Monte Carlo radiation transport-based computer simulations using a series of computational human phantoms from newborn to adults for both male and female was established, which is the first detailed paediatric CT scan database for the UK.
Abstract: Despite great potential benefits, there are concerns about the possible harm from medical imaging including the risk of radiation-related cancer. There are particular concerns about computed tomography (CT) scans in children because both radiation dose and sensitivity to radiation for children are typically higher than for adults undergoing equivalent procedures. As direct empirical data on the cancer risks from CT scans are lacking, the authors are conducting a retrospective cohort study of over 240 000 children in the UK who underwent CT scans. The main objective of the study is to quantify the magnitude of the cancer risk in relation to the radiation dose from CT scans. In this paper, the methods used to estimate typical organ-specific doses delivered by CT scans to children are described. An organ dose database from Monte Carlo radiation transport-based computer simulations using a series of computational human phantoms from newborn to adults for both male and female was established. Organ doses vary with patient size and sex, examination types and CT technical settings. Therefore, information on patient age, sex and examination type from electronic radiology information systems and technical settings obtained from two national surveys in the UK were used to estimate radiation dose. Absorbed doses to the brain, thyroid, breast and red bone marrow were calculated for reference male and female individuals with the ages of newborns, 1, 5, 10, 15 and 20 y for a total of 17 different scan types in the pre- and post-2001 time periods. In general, estimated organ doses were slightly higher for females than males which might be attributed to the smaller body size of the females. The younger children received higher doses in pre-2001 period when adult CT settings were typically used for children. Paediatric-specific adjustments were assumed to be used more frequently after 2001, since then radiation doses to children have often been smaller than those to adults. The database here is the first detailed organ-specific paediatric CT scan database for the UK. As well as forming the basis for the UK study, the results and description of the methods will also serve as a key resource for paediatric CT scan studies currently underway in other countries.

Journal ArticleDOI
TL;DR: Current diagnostic reference levels (DRLs) for the diagnostic trunk CT are too high for CT combined with PET, only performed in France for attenuation correction and localisation, and not for diagnostic purpose.
Abstract: A national survey of patient doses from 'whole-body PET-CT' examinations was conducted within all French nuclear medicine departments in 2011. Data related to injected [(18)F]-fluorodeoxyglucose (FDG) activity and to computerised tomography (CT) parameters were received from 56 positron emission tomography (PET)-CT units (answer rate: ∼60 %). The average specific injected FDG activity was equal to 4.3 MBq kg(-1), in agreement with European recommendations. The new 'time-of-flight' technology enabled to decreasing the specific activity down to 3.5 MBq kg(-1). The results have shown that current diagnostic reference levels (DRLs) for the diagnostic trunk CT are too high for CT combined with PET, only performed in France for attenuation correction and localisation, and not for diagnostic purpose. Despite wide variations between PET-CT units (4-fold factor in CTDI(vol)), DRLs equal to 8 mGy (CTDI(vol)) and 750 mGy cm (dose-length product) could be proposed for whole-body PET-CT. The average effective dose related to whole-body PET-CT examination in France has been assessed to ∼14 mSv.

Journal ArticleDOI
TL;DR: A simple model for proton relative biological effectiveness (RBE) was found to be able to reproduce the measured RBE values as a function of LET, depth and dose for a specific cell line.
Abstract: A simple model for proton relative biological effectiveness (RBE) is proposed. It describes the RBE as a function of proton depth, the dose and the linear energy transfer (LET) when proton passes through tissue-like materials. Radiobiological parameters were first obtained by fitting the published experimental cell survival data. The dose-averaged LET values were calculated for 250-MeV proton beam in a water phantom by using GEANT4 Monte Carlo simulation code and were then used as input values to calculate the values of RBE as function of depths. The model was also applied to proton spread-out Bragg peak, where the increasing RBE with depth causes an extended RBE-weighted dose in the distal fall-off region. This model was found to be able to reproduce the measured RBE values as a function of LET, depth and dose for a specific cell line.

Journal ArticleDOI
TL;DR: (222)Rn measurements in water samples collected from 27 wells and 19 taps that were supplied from the investigated wells were conducted using the AlphaGUARD PQ 2000PRO radon gas analyser at sites across several geologic formations within the city of Bursa, Turkey.
Abstract: (222)Rn measurements in water samples collected from 27 wells and 19 taps that were supplied from the investigated wells were conducted using the AlphaGUARD PQ 2000PRO radon gas analyser at sites across several geologic formations within the city of Bursa, Turkey. The measured radon concentrations ranged from 1.46 to 53.64 Bq l(-1) for well water and from 0.91 to 12.58 Bq l(-1) for tap water. Of the 27 sites sampled, only 7 had radon levels above the safe limit of 11.1 Bq l(-1) recommended by the USEPA. In general, all determined concentrations were well below the 100 Bq l(-1) revised reference level proposed by the European Union. These values of radon concentrations in water samples are compared with those reported from other countries. Doses resulting from the consumption of these waters were calculated. The minimum and the maximum annual mean effective doses due to (222)Rn intake through water consumption were 0.02 µSv a(-1) and 1.11 µSv a(-1), respectively.

Journal ArticleDOI
TL;DR: Investigation of dosimetric properties of alumina substrates and aspects of using mobile phones as personal dosemeters found favourable dosimetry characteristics, but anomalous fading had to be properly corrected in order for sufficient precision in dose estimate.
Abstract: Alumina substrate can be found in electronic components used in portable electronic devices. The material is radiation sensitive and can be applied in dosimetry using thermally or optically stimulated luminescence. Electronic portable devices such as mobile phones, USB flash discs, mp3 players, etc., which are worn close to the body, can represent personal dosemeters for members of the general public in situations of large-scale radiation accidents or malevolent acts with radioactive materials. This study investigated dosimetric properties of alumina substrates and aspects of using mobile phones as personal dosemeters. The alumina substrates exhibited favourable dosimetry characteristics. However, anomalous fading had to be properly corrected in order to achieve sufficient precision in dose estimate. Trial dose reconstruction performed by means of two mobile phones proved that mobile phones can be used for reconstruction of personal doses.

Journal ArticleDOI
TL;DR: The radium equivalent activity Ra(eq) and the external hazard index H(ex) of surface soils of Vietnam are lower than the corresponding permissible limits of 370 Bq kg(-1) and 1, respectively, and therefore, soil from Vietnam is safe for the human population when it is used as a building material.
Abstract: In this study, natural radioactivity in surface soils of Vietnam and external dose assessment to human population, deduced from activities of (226)Ra, (232)Th and (40)K nuclides, were determined. From 528 soil samples collected in 63 provinces of Vietnam, including five centrally governed cities, the average activities were obtained and equal to 42.77 ± 18.15 Bq kg(-1) for (226)Ra, 59.84 ± 19.81 Bq kg(-1) for (232)Th and 411.93 ± 230.69 Bq kg(-1) for (40)K. The outdoor absorbed dose rates (OADRs) in air at 1 m above the ground level for 63 provinces were calculated, and their average value was 71.72 ± 24.72 nGy h(-1), with a range from 17.45 to 149.40 nGy h(-1). The population-weighted OADR of Vietnam was 66.70 nGy h(-1), which lies in the range of 18-93 nGy h(-1) found in the World. From the OADRs obtained, it was estimated that the outdoor annual effective dose and indoor annual effective dose to the population were 0.082 and 0.458 mSv, which are higher than the corresponding values 0.07 and 0.41 mSv, respectively, of the World. The radium equivalent activity Ra(eq) and the external hazard index H(ex) of surface soils of Vietnam are lower than the corresponding permissible limits of 370 Bq kg(-1) and 1, respectively. Therefore, soil from Vietnam is safe for the human population when it is used as a building material.

Journal ArticleDOI
TL;DR: Although this study was performed with limited samples, DLP for adult patients were at comparable levels for all anatomical regions, and DRLs of paediatric head CTs reported from the EU or Syria tended to be higher in Japan.
Abstract: Optimisation of computed tomography (CT) parameters is important in avoiding excess radiation exposure. The aim of this study is to establish the diagnostic reference levels (DRL) of CT in Japan by using dose-length product (DLP). Datasheets were sent to all hospitals/clinics which had CT scanner(s) in Gunma prefecture. Data were obtained for all patients who underwent CT during a single month (June 2010), and the distributions of DLP were evaluated for eight anatomical regions and five patient age groups. The DRL was defined as the 25th and 75th percentiles of DLP. Datasheets were collected from 80 of 192 hospitals/clinics (26 090 patients). DLP for head CT of paediatric patients tended to be higher in Japan compared with DRLs of paediatric head CTs reported from the EU or Syria. Although this study was performed with limited samples, DLP for adult patients were at comparable levels for all anatomical regions.

Journal ArticleDOI
TL;DR: In this article, autologous adipose-derived regenerative cells (ADRCs) were injected in the wound bed and margin along with the injection of mixture of fat and ADRCs in the periphery.
Abstract: Effective therapy for chronic radiation injuries, such as ulcers, is prone to infection. Stiffness is expected since the therapeutic radiation often involves wider and deeper tissues and often requires extensive debridement and reconstruction, which are not sometimes appropriate for elderly and compromised hosts. Autologous adipose-derived regenerative cells (ADRCs) are highly yielding, forming relatively elderly aged consecutive 10 cases, 63.6±14.9 y (52-89 y), with mean radiation dose of 75.0±35.4 Gy (50-120 Gy) were included with at least 10-month follow-up. Minimal debridement and ADRC injection in the wound bed and margin along with the injection of mixture of fat and ADRCs in the periphery were tested for efficacy and regenerated tissue quality by clinically as well as imaging by computed tomography and magnetic resonance imaging. Uncultured ADRCs of 1.6±1.3×10(7) cells were obtained. All cases healed uneventfully after 6.6±3.2 weeks (2-10 weeks) post-operatively. The done site morbidity was negligible and without major complications, such as paralysis or massive haematoma. The regenerated tissue quality was significantly superior to the pre-operative one and the mixture of fat and ADRCs connected to the intact tissue was very soft and pliable. Mean follow-up at 1.9±0.8 y (0.9-2.9 y) revealed no recurrence or new ulceration after treatment. Thus, the ADRCs treatment for decades-long radiation injuries is effective, safe and improves the quality of wounds.


Journal ArticleDOI
TL;DR: The methodology and dosimetric models used to calculate these organ doses are described and the resulting doses for unit exposure to each source (radon gas, radon progeny and LLR) are presented.
Abstract: Epidemiological studies on uranium miners are being carried out to quantify the risk of cancer based on organ dose calculations. Mathematical models have been applied to calculate the annual absorbed doses to regions of the lung, red bone marrow, liver, kidney and stomach for each individual miner arising from exposure to radon gas, radon progeny and long-lived radionuclides (LLR) present in the uranium ore dust and to external gamma radiation. The methodology and dosimetric models used to calculate these organ doses are described and the resulting doses for unit exposure to each source (radon gas, radon progeny and LLR) are presented. The results of dosimetric calculations for a typical German miner are also given. For this miner, the absorbed dose to the central regions of the lung is dominated by the dose arising from exposure to radon progeny, whereas the absorbed dose to the red bone marrow is dominated by the external gamma dose. The uncertainties in the absorbed dose to regions of the lung arising from unit exposure to radon progeny are also discussed. These dose estimates are being used in epidemiological studies of cancer in uranium miners.

Journal ArticleDOI
TL;DR: Five samples of investigated commercial granite stones do not satisfy the safety criterion illustrated by UNSCEAR, but all investigated samples meet the exemption dose limit of 0.3 mSv y(-1).
Abstract: Due to increasing concern about environmental radiological protection, specific radioactivity concentrations of (226)Ra, (232)Th and (40)K in different types of commonly used granite stone samples collected from the Tehran city of Iran have been determined by means of a high-resolution HPGe gamma-spectroscopy system. The activity concentrations of (232)Th, (226)Ra and (40)K in the selected granite samples ranged from 18 to 178, 6 to 160 and 556 to 1539 Bq kg(-1), respectively. The radium equivalent activities (Ra(eq)) are lower than the limit of 370 Bq kg(-1) set by NEA-OECD [Nuclear Energy Agency. Exposure to radiation from natural radioactivity in building materials. Report by NEA Group of Experts. OECD (1979)], except in two samples. The internal hazard indexes have been found well below the acceptable limit in most of the samples. Five samples of investigated commercial granite stones do not satisfy the safety criterion illustrated by UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation. Exposure from natural sources of radiation. Report to the General Assembly (1993). Applying dose criteria recently recommended by the EC [European Commission Report on Radiological Protection Principles Concerning the Natural Radioactivity of Building Materials. Radiation Protection 112 (1999)] for superficial materials, all investigated samples meet the exemption dose limit of 0.3 mSv y(-1).

Journal ArticleDOI
TL;DR: The ImPACT CT Patient Dosimetry Calculator was used to compute values of organ doses for adult body CT examinations and the average cancer risk for chest/abdomen/pelvis CT examinations was higher than the cancer risk caused by 'sensitive organs'.
Abstract: The purpose of the study is to estimate cancer risks from the amount of radiation used to perform body computed tomography (CT) examination. The ImPACT CT Patient Dosimetry Calculator was used to compute values of organ doses for adult body CT examinations. The radiation used to perform each examination was quantified by the dose-length product (DLP). Patient organ doses were converted into corresponding age and sex dependent cancer risks using data from BEIR VII. Results are presented for cancer risks per unit DLP and unit effective dose for 11 sensitive organs, as well as estimates of the contribution from 'other organs'. For patients who differ from a standard sized adult, correction factors based on the patient weight and antero-posterior dimension are provided to adjust organ doses and the corresponding risks. At constant incident radiation intensity, for CT examinations that include the chest, risks for females are markedly higher than those for males, whereas for examinations that include the pelvis, risks in males were slightly higher than those in females. In abdominal CT scans, risks for males and female patients are very similar. For abdominal CT scans, increasing the patient age from 20 to 80 resulted in a reduction in patient risks of nearly a factor of 5. The average cancer risk for chest/abdomen/pelvis CT examinations was ∼26 % higher than the cancer risk caused by 'sensitive organs'. Doses and radiation risks in 80 kg adults were ∼10 % lower than those in 70 kg patients. Cancer risks in body CT can be estimated from the examination DLP by accounting for sex, age, as well as patient physical characteristics.

Journal ArticleDOI
TL;DR: Non-ionising radiation-monitoring networks in Greece are used to assess the changes in the outdoor electromagnetic environment with respect to location and time and there is a difference in the electric field between daytime and night, but not between morning and afternoon.
Abstract: Non-ionising radiation-monitoring networks were initiated as a result of the public concerns about the potential health effects from telecommunication emissions. In the present study, the data acquired from such networks in Greece are used to assess the changes in the outdoor electromagnetic environment with respect to location and time. The study shows that there is a statistically significant difference between the urban (median electric field: 1.1 V m(-1)) and the rural (median electric field: 0.3 V m(-1)) installations of monitoring units and also shows that there is a median diurnal variation (daily maximum to minimum) of 20.2 and 33.8 % for the broadcasting and mobile telecommunication emissions, respectively. Moreover, there is a difference in the electric field between daytime and night, but not between morning and afternoon. The results are in line with previously published data from spot measurements, monitoring networks and personal exposimeter studies performed in several European countries.

Journal ArticleDOI
TL;DR: The basic ideas of the dilatancy theory are presented which in principle can explain the occurrence of earthquake forerunners and the reasons for radon anomalies in soil gas and in ground water are clarified and a possible classification of radon anomaly is given.
Abstract: The observation of anomalies in the radon concentration in soil gas and ground water before earthquakes initiated systematic investigations on earthquake precursor phenomena. The question what is needed for a meaningful earthquake prediction as well as what types of precursory effects can be expected is shortly discussed. The basic ideas of the dilatancy theory are presented which in principle can explain the occurrence of earthquake forerunners. The reasons for radon anomalies in soil gas and in ground water are clarified and a possible classification of radon anomalies is given.

Journal ArticleDOI
TL;DR: In order to determine the existing capacity of BioDoseNet member laboratories, including their expertise and in vivo experience, involvement in national and international activities, problems, needs and prospects, an in-depth survey was conducted.
Abstract: Biodosimetry is an essential tool for providing timely assessments of radiation exposure, particularly when physical dosimetry is unavailable or unreliable. For mass-casualty events involving public exposure to ionising radiation, it is paramount to rapidly provide this dose information for medical management of casualties. The dicentric chromosome assay is currently the most reliable accepted method for biodosimetry; however, in a mass-casualty scenario, the throughput of this assay will be challenged by its time-consuming nature and the specific expertise required. To address this limitation, many countries have established expertise in cytogenetic biodosimetry and started developing surge capabilities through setting up regional networks to deal with emergency situations. To capitalise on this growing expertise and organise it into an internationally coordinated laboratory network, the World Health Organization has created and launched a global biodosimetry network (BioDoseNet). In order to determine the existing capacity of BioDoseNet member laboratories, including their expertise and in vivo experience, involvement in national and international activities, problems, needs and prospects, an in-depth survey was conducted. These survey results provide significant information on the current state of emergency cytogenetic biodosimetry capabilities around the world.

Journal ArticleDOI
TL;DR: Major contaminants from venting and hydrogen explosions at the Fukushima Daiichi nuclear reactors between 12 and 15 March 2011 were transported northwestward and deposited on soil and plants via precipitation and it is anticipated that decomposition of fallen leaves will promote recycling of radionuclides in the environment.
Abstract: Major contaminants from venting and hydrogen explosions at the Fukushima Daiichi nuclear reactors between 12 and 15 March 2011 were transported northwestward and deposited on soil and plants via precipitation. Surface soils and plant leaves were sampled at 64 sites in the Fukushima Prefecture. The highest concentrations of (134)Cs (84.4 kBq kg(-1)) and (137)Cs (82.0 kBq kg(-1)) in surface soils were observed at Nagadoro in Iidate village located 32 km northwest from the Fukushima Daiichi nuclear power plant. Furthermore, (131)I, (129)Te, (129 m)Te, (110 m)Ag and (140)La were detected in the same samples. Outer surface of plant leaves, such as bamboo, cabbage and grasses were highly contaminated at the high-dose rate areas of Tsushima and Minami-Tsushima in Namie town. Mugwort leaves that grew after the pollution event had extremely low concentration of radionuclides; however, the plant/soil radiocaesium ratio was 0.023 ± 0.006. It is anticipated that decomposition of fallen leaves will promote recycling of radionuclides in the environment.

Journal ArticleDOI
TL;DR: Thoron and its progeny concentrations were found to be comparatively high in the area and a comparison between the results obtained with various techniques is presented in this paper.
Abstract: Rn and its progeny. The results of thoron and its progeny measurements in the houses of highbackground radiation area (HBRA) of the southeastern coast of Odisha, India presented here. This area is one of the high back-ground radiation areas in India with a large deposit of monazite sand which is the probable source of thoron. Both active andpassive methods were employed for the measurement of thoron and its progeny in cement, brick and mud houses in the studyarea. Thoron concentration was measured using RAD-7 and Raduet. A CR-39 track detector was employed for the measure-ment of environmental thoron progeny, both in active and passive modes. Thoron and its progeny concentrations were found tobe comparatively high in the area. A comparison between the results obtainedwith varioustechniques is presented in this paper.

Journal ArticleDOI
TL;DR: The radiation exposure of fingers, thyroid and eyes of workers handling radiopharmaceuticals during various nuclear medicine procedures was measured using thermoluminescent dosemeters, and special concern should be devoted to the handling of (18)F.
Abstract: The radiation exposure of fingers, thyroid and eyes of workers handling radiopharmaceuticals during various nuclear medicine procedures was measured using thermoluminescent dosemeters. Dosemeters were placed on the finger tips of 19 workers on several different occasions for various procedures. Additionally, the routinely determined whole-body doses to various groups of workers were analysed. The finger dose measurements demonstrated clear differences between the various tasks, from 0.0012 µGy MBq(-1) (unpacking and installing (99)Mo/(99m)Tc-generator) to 3.0 µGy MBq(-1) (syringe withdrawal, injection and waste handling of (18)F-FDG). As long as the worker was handling (99m)Tc, the dose to the fingers was well below the ICRP dose limits, even when the activity was high. Special concern should, however, be devoted to the handling of (18)F, since the dose to the fingers could easily reach the dose limits. The estimated dose to eyes and thyroid was well below the dose limits. Since the introduction of the positron emission tomography/computed tomography facility, the annual whole-body dose has increased for those directly involved in the handling of (18)F. The annual whole-body dose of 0.2-2.5 mGy was, however, well below the dose limits.

Journal ArticleDOI
TL;DR: The use of a figure-of-merit (FOM) is a relatively new concept as a tool in digital mammography permitting quantitative assessment in terms of image quality and patient dose and this review summarises the available evidence.
Abstract: The use of image quality parameters in digital mammography such as contrast-to-noise ratio (CNR), signal-to-noise ratio (SNR) and detective quantum efficiency (DQE) has been widespread, with the intention of detector evaluation and/or quantitative evaluation of the system performance. These parameters are useful in ensuring adequate system performance when tests are done against international standards or guidelines. Parameters like CNR are relative quantities that lie within a range that is manufacturer and system dependent. The use of a figure-of-merit (FOM) is a relatively new concept as a tool in digital mammography permitting quantitative assessment in terms of image quality and patient dose. This review summarises the available evidence for the use and applicability of an FOM in digital mammography.

Journal ArticleDOI
TL;DR: Comparing FFDMs, the photon counting scanning-slit technology provides significantly lower MGDs than direct and indirect conversion digital technology, and the choice of target/filter combination influences the MGD, and has to be optimised with regard to breast thickness.
Abstract: This is a pre-copy-editing, author-produced PDF of an article accepted for publication in Radiation protection dosimetry following peer review. The definitive publisher-authenticated version Hauge, I. H. R., Pedersen, K., Sanderud, A., Hofvind, S. & Olerud, H. M. (2011). Patient doses from screen-film and full-field digital mammography in a population-based screening programme. Radiation protection dosimetry is available online at: http://dx.doi.org/10.1093/rpd/ncq598.