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Latent fingerprint developed at the site of crime is considered as crucial physical evidence in forensic investigation. The mixed metal oxides (MXOY, M = Ba, Zn, Al, Ce) nanophosphor was synthesised by irradiating the precursor solution with 60Co gamma radiation followed by solution combustion method. The structural, morphological, optical characteristics and fingerprint imaging were studied using X-ray diffraction (XRD), scanning electron microscopy, UV-visible spectroscopy and powder dusting method, respectively. The XRD results revealed that the average crystallite size is found to be 30 nm with the estimated bandgap of 3.18 eV. The broadband UV exited luminescence of the phosphors was observed at λMax = 330 nm. The PL spectrum shows three emission bands at 432, 444 and 460 nm that corresponds to blue regions, suggesting that the synthesised nanophosphor is a potential luminous material for latent fingerprinting and luminescent devices., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Two commercially available portable Rapid DNA instruments were evaluated for their ability to process 1 µL and 10 µL saliva samples deposited on metal and plastic surfaces and contaminated with surrogates of cesium (Cs)-137, strontium (Sr)-90 and cobalt (Co)-60; radioactive materials potentially released during a nuclear weapon accident or a radiological dispersal device detonation. A comparable success rate was noted for both Rapid DNA instruments when considering the number of complete and balanced DNA profiles, the number of profiles with a minimum of 10 autosomal STR loci (out of 23 [FlexPlex™ 27] or 21 [GlobalFiler™ Express]), and the possibility to search a national DNA database in Canada and the United States. Cobalt had an adverse impact on the quality of the megaplex short tandem repeat (STR) DNA profiles derived on each instrument for two of the three contamination levels tested in this study, i.e., 0.05 M and 0.1 M as reflected by a reduced number of detected alleles and decreased profile peak heights. Strontium exhibited some adverse effect on the Rapid DNA results when used at the highest contamination level (0.1 M) whereas cesium had none. No new artifacts were observed in the Rapid DNA profiles of samples spiked with the non-radiogenic surrogates. Importantly, in the context of a radiological/nuclear (RN) event, the ANDE™ 6C offers the possibility to dispose of all radioactive materials associated with contaminated samples quickly using a chip on which all steps of the Rapid DNA process are performed whereas the RapidHIT™ ID accumulates radioactive materials for many days before disposal. An individual handling 25 samples in a week (5 per day) on the RapidHIT™ ID at a 30.5 cm distance with a 5 min exposure to the radioactive source estimated at every run would exceed the 0.042 µSv/5 min limit with gamma dose rates for Cs at 0.13 mSv and for Co at 3.8 mSv. Beta dose rates calculated for the surrogate isotopes at the three concentrations tested were also above the recommended radiation exposure limit of 1 mSv/yr (0.042 µSv/5 min). Various potential mechanisms of action behind the interference noted for Sr and Co at high concentrations are presented. These elements may play a role in the steps prior to PCR (at the DNA molecule by binding to bases or to phosphate groups), during PCR (at the DNA polymerase as cofactors for catalytic sites), or even during amplified DNA fragment detection (as fluorescence quenchers)., Competing Interests: Declaration of Competing Interest None., (Crown Copyright © 2023. Published by Elsevier B.V. All rights reserved.)

CDC designed a rapid HPGe Bioassay Method for 137 Cs, 60 Co, and 192 Ir that is suitable for a public health response to a radiological incident where people may ingest or inhale radionuclides. The method uses a short count time, small sample volume, and a large volume detector and well size. It measures a patient's urine sample collected post-incident. The levels of concern are directly related to the Clinical Decision Guide levels recommended in the National Council of Radiation Protection 161., (Published by Elsevier Ltd.)

Operational practices in nuclear power utilities often restrict job assignments for workers with internal contamination due to the difficulty of monitoring for new intakes and strict radioactive material controls. However, restriction of job assignments for an extended period (i.e., months to years) may be too conservative. An industry consensus on guidance in these conditions would be helpful for Radiation Safety Officers (RSOs) to allow long term contaminated workers to have less work restrictions.

As a by-product of another measurement, ratios of the single-escape (SE) and double-escape (DE) efficiencies relative to the full-energy-peak efficiency (FE) have been measured for two HPGe detectors for 60 Co. For a 2.5-cm-thick 95 cm 3 crystal the results were SE/FE = 0.000 48 ± 0.000 20 and 0.003 25 ± 0.000 24 for 1173 and 1332 keV gamma-rays, respectively, and DE/FE = 0.000 90 ± 0.000 17 and 0.003 41 ± 0.000 11 for 1173 and 1332 keV, respectively. For a 3.0-cm-thick 84 cm 3 crystal the results were SE/FE = 0.000 67 ± 0.000 32 and 0.003 79 ± 0.000 27 for 1173 and 1332 keV respectively, and DE/FE = 0.001 05 ± 0.000 28 and 0.004 29 ± 0.000 16 for 1173 and 1332 keV, respectively. These measurements may be of relevance in connection with Monte Carlo calculations of HPGe detector efficiencies, and may also suggest a path towards improved atomic cross-section measurements.

The IAEA is currently coordinating a multi-year project to update the TRS-398 Code of Practice for the dosimetry of external beam radiotherapy based on standards of absorbed dose to water. One major aspect of the project is the determination of new beam quality correction factors, k Q , for megavoltage photon beams consistent with developments in radiotherapy dosimetry and technology since the publication of TRS-398 in 2000. Specifically, all values must be based on, or consistent with, the key data of ICRU Report 90. Data sets obtained from Monte Carlo (MC) calculations by advanced users and measurements at primary standards laboratories have been compiled for 23 cylindrical ionization chamber types, consisting of 725 MC-calculated and 179 experimental data points. These have been used to derive consensus k Q values as a function of the beam quality index TPR 20,10 with a combined standard uncertainty of 0.6%. Mean values of MC-derived chamber-specific [Formula: see text] factors for cylindrical and plane-parallel chamber types in 60 Co beams have also been obtained with an estimated uncertainty of 0.4%.

To provide Monte Carlo calculated beam quality correction factors (k Q ) for monoenergetic proton beams using [Formula: see text], a toolkit based on the Monte Carlo code [Formula: see text]. Monte Carlo simulations of six plane-parallel and four cylindrical ionization chambers were carried out. The latest ICRU 90 recommendations on key data for ionizing-radiation dosimetry were used to calculate the electronic stopping powers and to select the mean energy necessary to create an ion pair in air ([Formula: see text]). [Formula: see text] factors were calculated for a 60 Co spectrum at a depth of 5 g cm -2 . f  Q factors and [Formula: see text] ratios as well as k Q factors were calculated at the entrance region of monoenergetic proton beams with energies between 60 MeV and 250 MeV. Additionally, perturbation correction factors for the Exradin A1SL ionization chamber at an energy of 250 MeV were calculated. [Formula: see text] factors agreed within 0.7% or better, f  Q factors within 1.7% or better and [Formula: see text] ratios within 2.2% or better with Monte Carlo calculated values provided in the literature. Furthermore, k Q factors calculated in this work were found to agree within 1% or better with experimentally determined k Q factors provided in the literature, with only two exceptions with deviations of 1.4% and 2.4%. The total perturbation correction factor for the Exradin A1SL chamber was 0.969(7) and hence significantly different than unity in contrast to the assumption from the IAEA TRS-398 code of practice (CoP). [Formula: see text] can be used to calculate k Q factors in clinical proton beams. k Q factors for six plane-parallel and four cylindrical ionization chambers were calculated and provided for the upcoming update of the IAEA TRS-398 CoP.

The primary standard for air kerma of the Slovak Institute of Metrology (SMU) as a part of national standard of dosimetric quantities of gamma radiation NE028/02, based on cylindrical graphite walled cavity ionization chamber was established in 2002 for the 60Co gamma ray beams. Since then the main role of SMU was to continuously maintain, develop and refurbish the standard with related accessory to ensure international equivalence. Since 2002, a re-evaluation of the active volume of the ionizing chamber, correction factors, the key data, due to adoption of ICRU Report 90(1), and changes of the calibrations methods and corrections of the equipment were made to obtain improved parameters. The range was extended for 137Cs gamma ray beams and key comparisons with the Bureau International des Poids et Mesures (BIPM) were performed. ICRU Report 90(1) implementation led to a decrease of the Gray of -0.84% for 60Co and -0.80% for 137Cs., (© The Author(s) 2020. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

In 2016, the EURADOS working group 12 started a project to gather reliable data concerning the behavior of active personal dosemeters (APDs) used by European hospitals in standardized pulsed and hospital fields. This paper concentrates on the tests that deal with the dose rate dependence of APDs in laboratory tests. The dependence on the dose rate was determined for 10 dosemeter types with continuous radiation of a 60Co source and pulsed radiation of the reference radiation facility of Physikalisch-Technische Bundesanstalt. Furthermore, irradiations were done with continuous radiation of a 137Cs source of the Karlsruher Institute of Technology and with continuous X-rays of the two radiation qualites in radiation beams emerging from the X-ray source assembly, RQR5 and RQR8, of Nofer Institute of Occupational Medicine. For the first time, APDs have been systematically investigated under laboratory conditions in a pulsed reference fields according to ISO/TS 18090-1 and the experience gained by these test procedures will be included in the new IEC/TS 63050., (© The Author(s) 2019. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The intercomparison test is a quality assurance activity performed for internal dose assessment. In Korea, the intercomparison test on internal dose assessment was carried out for nuclear facilities in May 2018. The test involved four nuclear facilities in Korea, and seven exposure scenarios were applied. These scenarios cover the intake of 131I, a uranium mixture, 60Co and tritium under various conditions. This paper only reviews the participant results of three scenarios pertinent to the operation of nuclear power plants and adopts the statistical evaluation method, used in international intercomparison tests, to determine the significance values of the results. Although no outliers were established in the test, improvements in the internal dose assessment procedure were derived. These included the selection of intake time, selection of lung absorption type according to the chemical form and consideration of the contribution of previous intake., (© The Author(s) 2019. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Objective: To assess an impact of the Rivne Nuclear Power Plant (RNPP) activity on the control area (CA) environ- ment according to environmental and radiation monitoring data over time of 2011-2017 as a component of the radiation safety system., Materials and Methods: Review of geographical and natural features of the territory of the «Rivne NPP» manufac- turing facility was carried out to assess its CA environment. Assessment of environmental and radiation situation of the CA was carried out according to the data of RNPP monitoring systems and a number of state institutions of Rivne oblast over time of 2011-2017. Opinion of the CA population about the RNPP environmental impact was studied. The sampled population of respondents was calculated based on the total population living in CA. The sampling error no more that 7.0%. Data from sociological survey of population were calculated using the statistical programs., Results: The radiation impact of RNPP on environment is related to emissions and discharges of radioactive sub- stances generated in the production cycle. Over time the total index of radionuclide discharge to the Styr River since 2011 is of a marked downward trend from 2.11 % to 0.18 %. The maximum concentrations of 60Co and 137Cs radionuclides at the three sampling points along the Styr River over time of 2011-2016 were about one thousandth of a percent, and of 131I - one hundredth of a permissible value according to the Radiation Safety Standards of Ukraine (RSSU). Emissions of inert radioactive gases and long-lived nuclides into the atmosphere were less than 0.2 % and iodine emissions were 0.01 % to the emission limit. Average radionuclide concentrations in the natural air of the RNPP CA settlements did not exceed the admissible concentration limit (ACL). Concentrations of chem- ical pollutants in discharges of the RNPP to the Styr River over time of 2012-2017 did not exceed the ACL. Integral wastewaters of municipal enterprises of the CA and RNPP result in an increased index of biochemical oxygen uti- lization and ammonium salt content in the Styr River, exceeding the ACL in fishery reservoir water. No exceedance of ACL of repugnant substances in the open air of settlements was observed regarding the pollutants under study. According to population survey the radiation contamination of territories as a result of the ChNPP accident and RNPP activities, which cause anxiety, are the key factors determining an environmental situation at the place of residence. The correlation coefficients between anxiety index and public estimates of environmental situation are established., Conclusions: Content of radionuclides in emissions and discharges generated in the RNPP production cycle under everyday conditions does not exceed the allowed RSSU-97 values. The combined discharges of collective enterpri- ses and RNPP are the main sources of chemical pollution of surface waters in CA. There is a higher correlation coef- ficient between the anxiety and somatization rates and environmental sphere parameter in rural population com- pared to urban one. The combined effect of environmental, radiation and psychological factors on the RNPP CA population makes the health studies necessary in the latter., (V. A. Prylypko, M. M. Morozova, I. V. Bondarenko, O. O. Petrychenko, O. M. Romanenko, K. K. Tuz, Yu. Yu. Ozerova.)

The majority of the radiation accidents with early acute clinical effects were associated with the orphan sources used in industrial and medical facilities. These accidents involved members of general public, who were entirely unaware of the exposure to the radiation. In such situations, the exposure commonly occurs when the source is in contact with a body of a victim, primarily located in pockets of clothing or in hands. In this research, the average absorbed doses in internal organs, skin and tissues close to the source were assessed using the phantom modeling of contact human exposure by the sealed 192Ir, 137Cs and 60Co gamma sources. The results allow estimating the RBE-weighted absorbed dose values in organs and tissues to assess the possibility and severity of deterministic medical effects caused by the exposure and to compare them with the reference levels established by IAEA for performing the protective and medical actions., (© The Author(s) 2019. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The removal of Co, Sr and Cs ions form simulated radioactive wastewater using forward osmosis (FO) process was investigated. The effect of various factors on nuclide transport was examined, including membrane orientation, NaCl concentration, flow velocity, and the main factors were identified by correlation analysis. The mechanisms of nuclides transfer through membrane were explored. The results indicated that the active layer facing draw solution (AL-DS) had higher nuclide flux than AL-FS. At AL-FS mode, the highest flux of Co, Sr and Cs were only 1.54, 10.22 and 15.63 mg m -2 h -1 respectively by cellulose triacetate with embedded polyester screen support (CTA-ES) membrane. At AL-DS mode, the flux of Co and Cs increased when NaCl concentration and flow velocity increased. Convection, diffusion and electrostatic interactions were found to influence the nuclide transport all together. The Pearson correlation and partial correlation analysis identified that the diffusion coefficient of nuclides and reverse NaCl flux were the most important factors affecting nuclide flux through cellulose triacetate membrane. The water flux, NaCl concentration, flow velocity and partition coefficient were not the main affecting factors for nuclide flux., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Soil transport on fully vegetated land surfaces is typically detachment limited. Rates of soil and nutrient transport, and ultimately long-term landscape evolution, are controlled by processes that supply soil material for entrainment and transport. Despite their on-going nature, many such processes operate at low rates and have not been subject to detailed investigation. We present preliminary findings from a prototype tracing approach to quantify one such process; namely to determine the relative mobility of sediment from earthworm casts on a fully vegetated hillslope surface. A 0.6 ∗ 0.5 m bounded area of pasture was prepared and fifteen intact earthworm casts representing 203 g of soil were labelled with an estimated 216 Bq of caesium-134 ( 134 Cs) activity and evenly distributed across the upslope half of the plot, 0.3-0.6 m from the downslope outlet. A further 15 intact casts representing 190.7 g of soil were labelled with 224 Bq of cobalt-60 ( 60 Co) activity and distributed between 0.3 and 0.0 m from the same outlet. All labelled casts were exposed to natural weather events over 76 days, during which time 186.3 mm of rainfall generated 16 runoff samples. A mass balance was used to partition labelled sediment from the unlabelled material. A total of 27.17 g of 60 Co-labelled casts, equivalent to 14.2% of the original mass deployed, was recovered from a distance of ≤0.3 m from their original locations. In contrast, 8.77 g of 134 Cs-labelled casts, equivalent to 4.3% of the original mass deployed, was recovered from a distance ≥0.3 m from their original locations. Some runoff-derived samples recorded an over-enrichment of radionuclide material, which suggests that intact casts may sorb more material than the original assumption predicts. Ways in which sorption can be more accurately quantified to improve the accuracy of the tracing approach are outlined., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background and Motivation: While small molecules can be used in cancer diagnosis there is a need for imageable diagnostic NanoParticles (NPs) that act as surrogates for the therapeutic NPs. Many NPs are composed of hydrophobic materials so the challenge is to formulate hydrophobic imaging agents. To develop individualized medical treatments based on NP, a first step should be the selection of patients who are likely responders to the treatment as judged by imaging tumor accumulation of NPs. This requires NPs with the same size and structure as the subsequent therapeutic NPs but labelled with a long-lived radionuclide. Cobalt isotopes are good candidates for NP labelling since 55 Co has half-life of 17.5 h and positron energy of 570 keV while 57 Co (t 1/2 271.6 d) is an isotope suited for preclinical single photon emission tomography (SPECT) to visualize biodistribution and pharmacokinetics of NPs. We used the hydrophobic octaethyl porphyrin (OEP) to chelate cobalt and to encapsulate it inside hydrophobic liquid NPs (LNPs). We hypothesized that at least two additional hydrophobic axial ligands (oleylamine, OA) must be provided to the OEP-Co complex in order to encapsulate and retain Co inside LNP., Results: 1. Cobalt chelation by OEP and OA. The association constant of cobalt to OEP was 2.49 × 10 5 M -1 and the formation of the hexacoordinate complex OEP-Co-4OA was measured by spectroscopy. 2. NP formulation and characterization: LNPs were prepared by the fast ethanol injection method and were composed of a liquid core (triolein) surrounded by a lipid monolayer (DSPC:Cholesterol:DSPE-PEG 2000 ). The size of the LNPs loaded with the cobalt complex was 40 ± 5 nm, 3. Encapsulation of OEP-Co-OA: The loading capacity of OEP-Co-OA in LNP was 5 mol%. 4. Retention of OEP- 57 Co-4OA complex in the LNPs: the positive effect of the OA ligands was demonstrated on the stability of the OEP- 57 Co-4OA complex, providing a half-life for retention in PBS of 170 h (7 days) while in the absence of the axial OA ligands was only 22 h. 5 Biodistribution Study: the in vivo biodistribution of LNP was studied in AR42J pancreatic tumor-bearing mice. The estimated half-life of LNPs in blood was about 7.2 h. Remarkably, the accumulation of LNPs in the tumor was as high as 9.4% ID/g 24 h after injection with a doubling time for tumor accumulation of 3.22 h. The most important result was that the nanoparticles could indeed accumulate in the AR42J tumors up to levels greater than those of other NPs previously measured in the same tumor model, and at about half the values reported for the molecular agent 57 Co-DOTATATE., Conclusions: The additional hydrophobic chelator OA was indeed needed to obtain a stable octahedral OEP-Co-4OA. Cobalt was actually well-retained inside LNP in the OEP-Co-4OA complex. The method described in the present work for the core-labelling of LNPs with cobalt is now ready for labeling of NPs with 55 Co, or indeed other hexadentate radionuclides of interest for preclinical in vivo PET-imaging and radio-therapeutics., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The uptake and depuration kinetics of dissolved 109 Cd, 57 Co and 134 Cs were determined experimentally in the European flat oyster Ostrea edulis (Linnaeus, 1758) under different pH conditions (i.e., 8.1, 7.8 and 7.5) for 59 days. Uptake and depuration rates were variable within these elements; no effects were observed under different pH conditions for the uptake biokinetics of 109 Cd and 57 Co and depuration of 109 Cd and 134 Cs in oyster. The uptake and depuration rate constants of 134 Cs differed during the exposure phase between treatments, while the steady state concentration factors (CF ss ) were similar. The resulting Cs activity that was purged during short- and long-term depuration phases differed, while the remaining activities after thirty-nine days depuration phase (RA 39d ) were similar. Co-57 depuration was affected by pCO 2 conditions: RA 39d were found to be significantly higher in oysters reared in normocapnia (pCO 2  = 350 μatm) compared to high pCO 2 conditions. Co-57 tissue distribution did not differ among the variable pCO 2 conditions, while 109 Cd and 134 Cs accumulated in soft tissue of oysters were found to be higher under the highest pCO 2 . Additionally, Cd, Co and Cs were stored differently in various compartments of the oyster cells, i.e. cellular debris, metal-rich granules (MRG) and metallothionein-like proteins (MTLP), respectively. The subcellular sequestration of the elements at the end of the depuration phase did not differ among pH treatments. These results suggest that bioconcentration and tissue/subcellular distribution are element-specific in the oyster, and the effects of higher pCO 2 driven acidification and/or coastal acidification variably influence these processes., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

This paper summarizes the results of the decontamination of the infrastructure materials concrete, limestone, brick and asphalt contaminated with 60 Co, 85 Sr, 137 Cs and 241 Am. The paper focuses on the effect of differences in substrate properties and of the pH of the radionuclide solution used for surface contamination on adsorption or ion exchange of the radionuclides and how these factors affect the decontamination effectiveness. A six-component chemical formulation was used and a process effectiveness of up to 76% was obtained depending on the substrate and radionuclide. Asphalt was the easiest material to decontaminate because of its more hydrophobic nature. Concrete and limestone (and to some extent brick) were less effectively decontaminated as their porous surfaces allowed penetration of radionuclides into water-filled pores in the substrate facilitating adsorption or ion exchange and making them difficult to remove. Brick was the most difficult material to decontaminate because the major component of brick is clay which retains most mono- and divalent ions. The removal of 60 Co, 85 Sr and 137 Cs from the surfaces of concrete, limestone and brick increased when the pH of the radionuclide solutions was moderately acidic to neutral compared to when they were highly acidic. The variability in the test results was similar to that observed in other studies using other decontamination methods, attributed to the inhomogeneity of the substrates used and considered representative of real infrastructure materials., (Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.)

Experimentally and theoretically determined shielding factors for a common light construction dwelling type were obtained and compared. Sources of the gamma-emitting radionuclides 60 Co and 137 Cs were positioned around and on top of a modular building to represent homogeneous fallout. The modular building used was a standard prefabricated structure obtained from a commercial manufacturer. Four reference positions for the gamma radiation detectors were used inside the building. Theoretical dose rate calculations were performed using the Monte Carlo code MCNP6, and additional calculations were performed that compared the shielding factor for 137 Cs and 134 Cs. This work demonstrated the applicability of using MCNP6 for theoretical calculations of radioactive fallout scenarios. Furthermore, the work showed that the shielding effect for modular buildings is almost the same for 134 Cs as for 137 Cs., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

This study aimed to evaluate dose uniformity for 192 Ir and 60 Co stepping sources. High dose rate 192 Ir and 60 Co stepping sources were simulated by the MCNPX Monte Carlo code. To investigate dose uniformity, treatment lengths of 30, 50, 100, and 150 mm with stepping distances of 3, 5, 7, and 10 mm were considered. Finally, dose uniformity for the 192 Ir and 60 Co stepping sources with increasing distances from the source were assessed at these treatment lengths and steps. The findings showed that the dose distribution was non-uniform for regions in close vicinity of the source, especially in the high source steps, but for most points at distances >10 mm from the center of the source, the dose distribution was uniform. For most points, the dose uniformity increased with reduction of the source steps and increments of the transverse distance from the source. The dose non-uniformity was similar for most of the corresponding points of 60 Co and 192 Ir sources with the same treatment lengths and source steps, except at the distance of 150 mm. When using stepping technique for the treatment of tumors, more attention should be focused on treatment planning, especially with higher stepping distances and lower transverse distances from the source.

Source-based calibration methods used for photon attenuation and coincidence summing corrections are time consuming and require multiple certified standards that match sample geometry with varying densities. Three programs which are capable of simulating a variety of sample geometries, matrix compositions, and sample densities have been examined as alternatives. LabSOCS, ANGLE 3 and GESPECOR are effective at generating efficiency curves for food matrices with a range with different densities. The curves generated have been successfully used to determine activity in food samples., (Published by Elsevier Ltd.)

An early warning system for detection of increased levels of radioactivity in outdoor air was operative between 2004 and 2011 at the Swedish air sampling stations. The system consisted of a low resolution detector (NaI), positioned directly behind the filter and measurement of the accumulated radioactivity were performed continuously. An evaluation of the data collected during the period is presented with emphasis on natural occurring radionuclides and their influence on the detectability of anthropogenic radionuclides., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Living organisms have homochiral L-amino acids in proteins and homochiral D-mononucleotides in nucleic acids. The chemical evolutionary process to protein homochirality has been discussed for many years. Although many scenarios have been proposed for homochirality in the monomeric compounds, homochirality in amino acids and mononucleotides does not always guarantee homochirality in polypeptides and polynucleotides. Integrated scenarios containing the pathways from monomer to polymer should be proposed because in the pathways oligomers and polymers as well as monomers racemize (or epimerize), degrade, and condense. This research addresses epimerization and degradation of dipeptides under γ-rays irradiation by a cobalt-60 ( 60 Co) radiation source. The different rate constants of epimerization between diastereomeric dipeptides in the research suggest that the potential pathway toward homochirality could be much more complex.

The paper presents a study of the sorption properties of sediments of different geological ages and lithological types, governing radionuclide retention in the subsurface (up to 160 m beneath the surface) within the area of potential influence of the Northwestern Center of Atomic Energy (NWCAE), St. Petersburg region, RF. The focus of this work is mostly on the sedimentary rocks of two types, i.e., weakly cemented sandstone and lithified clay formations of Cambrian and Vendian series. The first lithological unit is associated with a groundwater reservoir (Lomonosov aquifer), and the second one, with both a relative aquitard in the upper part of the Vendian formation (Kotlin clay) and a regional aquifer (Gdov aquifer) in the lower part of the formation. The main mechanisms responsible for the variability of the sorption distribution coefficient (Kd, defined as the ratio of the concentration of solute on solid phase to its concentration in solution at equilibrium) was identified for radionuclides such as Sr-90, Cs-137, Co-60, Pu-239,240, and Am-241. It was shown that the main factors contributing to the chemical heterogeneity of the Cambrian sandstone were related to the presence of secondary minerals (iron and magnesium oxides and hydroxides produced by the weathering process) in trace amounts, forming correlated layer structures. The statistical analysis of nonlinear isotherms confirmed this conclusion. For the Vendian formation, a determinate trend was established in the Kd change over depth as a result of temporal trends in the sedimentation process and pore-water chemistry. The geostatistical characteristics and the spatial correlation models for describing linear sorption of different radionuclides are not identical, and the exhibition of chemical heterogeneity of sedimentary rock of a particular lithological type depends on radionuclide chemistry. Moreover, variogram analysis for some Kd data sets (both in Cambrian and Vendian formations) demonstrates the total absence of auto-correlation (pure nugget effect). It can be supposed that sampling distances did not allow the evaluation of small-scale variability in sediment sorption properties., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The Dosimetry Laboratory Seibersdorf was the irradiation laboratory for the IC2014 EURADOS intercomparison for individual monitoring. One hundred and twelve whole-body dosimetry systems with 30 dosemeters per dosimetry system participated in the intercomparison. In total, 2240 personal dosemeters were irradiated in photon reference radiation fields on the ISO water slab phantom in terms of personal dose equivalent Hp(10) and Hp(0.07). Two nuclide irradiation systems ((137)Cs and (60)Co gamma radiation) and a 320-kV X-ray radiation unit were used. The irradiation plan consisted of nine irradiation set-ups with five different ISO/IEC photon radiation qualities (S-Cs, S-Co, RQR 7, W-80 and W-150) and two different angles of radiation incidence (0° and 60°). Reference dose equivalent values were in the range of ∼1-500 mSv. Reference values were based on air kerma rate traceable to primary standard calibrations and appropriate conversion coefficients resulting in total expanded measurement uncertainties <6 %., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The individual monitoring service at the Helmholtz Zentrum München has adopted the recommendations of the ISO 4037 and 6980 standards series as base of its dosimetric systems for X-ray, gamma and beta dosimetry. These standards define technical requirements for radiation spectra and measurement processes, but leave flexibility in the implementation of irradiations as well as in the resulting uncertainty in dose or dose rate. This article provides an example for their practical implementation in the Munich IAEA/WHO secondary standard dosimetry laboratory. It focusses on two aspects: automation issues and uncertainties in calibration., (© The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The aim of this paper was to calculate the True Coincidence Summing Correction Factors (TSCFs) for an HPGe coaxial detector in order to correct the summing effect as a result of the presence of (88)Y and (60)Co in a multigamma source used to obtain a calibration efficiency curve. Results were obtained for three volumetric sources using the Monte Carlo toolkit, GEANT4. The first part of this paper deals with modeling the detector in order to obtain a simulated full energy peak efficiency curve. A quantitative comparison between the measured and simulated values was made across the entire energy range under study. The True Summing Correction Factors were calculated for (88)Y and (60)Co using the full peak efficiencies obtained with GEANT4. This methodology was subsequently applied to (134)Cs, and presented a complex decay scheme., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

A new large-volume metal reference standard has been developed. The intended use is for calibration of free-release radioactivity measurement systems and is made up of cast iron tubes placed inside a box of the size of a Euro-pallet (80 × 120 cm). The tubes contain certified activity concentrations of (60)Co (0.290 ± 0.006 Bq g(-1)) and (110m)Ag (3.05 ± 0.09 Bq g(-1)) (reference date: 30 September 2013). They were produced using centrifugal casting from a smelt into which (60)Co was first added and then one piece of neutron irradiated silver wire was progressively diluted. The iron castings were machined to the desirable dimensions. The final material consists of 12 iron tubes of 20 cm outer diameter, 17.6 cm inner diameter, 40 cm length/height and 245.9 kg total mass. This paper describes the reference standard and the process of determining the reference activity values., (© The Author 2015. Published by Oxford University Press.)

The excitation functions of the (54)Fe(d,n)(55)Co, (56)Fe(p,2n)(55)Co and (58)Ni(p,α)(55)Co reactions were analyzed with relevance to the production of the β(+)-emitter (55)Co (T½=17.53 h), a promising cobalt radionuclide for PET imaging. The nuclear model codes ALICE-IPPE, EMPIRE and TALYS were used to check the consistency of the experimental data. The statistically fitted excitation function was employed to calculate the integral yield of the product. The amounts of the radioactive impurities (56)Co and (57)Co were assessed. A comparison of the three investigated production routes is given., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

A portable DNA extraction instrument was evaluated for its ability to decontaminate blood and saliva samples deposited on different surfaces (metal, plastic and glass) contaminated with stable isotopes of cobalt (Co), cesium (Cs), and strontium (Sr) as equivalents to their radiogenic (60)Co, (137)Cs, and (90)Sr isotopes, respectively, that could be released during a nuclear weapon accident or a radiological dispersal device (RDD) detonation. Despite the very high contamination levels tested in this study, successful removal of greater than 99.996% of the Co, Cs, Sr contaminants was achieved based on inductively coupled plasma-mass spectrometry (ICP-MS) and neutron activation analyses carried out on all liquids (including DNA eluates) and solid waste produced during automated DNA extraction. The remaining amounts of Co, Cs and Sr in the DNA eluates, when converted to dose rates (corresponding to (60)Co, (137)Cs and (90)Sr), were determined to be below the recommended dose limits for the general public in most of the scenarios tested. The presence of Co, Cs and Sr contaminants in the cell lysates had no adverse impact on the binding of DNA onto the magnetic DNA IQ™ beads. DNA yields were similar to uncontaminated controls. The remaining Co, Cs and Sr in the DNA eluates did not interfere with real-time PCR DNA quantification. In addition, the quality of the AmpFlSTR(®) Identifiler(®) profiles derived in 26min using an accelerated protocol was very good and comparable to controls. This study emphasizes the use of an accelerated process involving a portable DNA extraction instrument to significantly reduce radioactive dose rates to allow contaminated samples to be processed safely in a forensic mobile laboratory to expedite the identification of individuals potentially involved in the dispersal of nuclear or other radioactive materials., (Crown Copyright © 2016. Published by Elsevier Ireland Ltd. All rights reserved.)

The response of LiF:Mg,Cu,P thermoluminescence dosemeters (type GR-200A) to monoenergetic radiation of energy 28, 35, 38 and 40 keV was evaluated with respect to irradiation with a calibrated (60)Co gamma-ray source. High-precision measurements of the relative air kerma response performed at the SYRMEP beamline of the ELETTRA synchrotron radiation facility (Trieste, Italy) showed a significant deviation of the average response to low-energy X-rays from that to (60)Co, with an over-response from 6 % (at 28 keV) to 22 % (at 40 keV). These data are not consistent with literature data for these dosemeters, where model predictions gave deviation from unity of the relative air kerma response of about 10 %. The authors conclude for the need of additional determinations of the low-energy relative response of GR-200A dosemeters, covering a wider range of monoenergetic energies sampled at a fine energy step, as planned in future experiments by their group at the ELETTRA facility., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Radionuclides released in water systems--as well as heavy metals and organic toxicants--sorb to both the suspended solid particles and the bed sediments. Sorption is usually represented mathematically by the distribution coefficient. This approach implies equilibrium between phases and instantaneous fixation (release) of the pollutant onto (from) the surface of the soil particle. However, empirical evidence suggests that for some radionuclides the fixation is not achieved instantaneously and that the reversibility of the process can be slow. Here the adsorption/desorption kinetics of (60)Co and (137)Cs in fresh water environments were simulated experimentally and later on modelled mathematically, while the influence of the most relevant factors affecting the sorption were taken into account. The experimental results suggest that for adsorption and the desorption more than 24 h are needed to reach equilibrium, moreover, It was observed that the desorption rate constants for (60)Co and (137)Cs lie within ranges which are of two to three orders of magnitude lower than the adsorption rate constants., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

This paper reports response of p-channel MOSFETs (RADFETs) to (60)Co gamma radiation in the 10-50 Gy dose range and signal fading (room temperature annealing) for 100 days after irradiation. RADFETs with three different thicknesses of the gate oxide layer were used. Irradiations were performed at gate biases ranging from 0 to 5 V. Threshold voltage shift was monitored during the irradiations and the subsequent fading. The dependence of the threshold voltage shift on the radiation dose is linear for the RADFETs with 100 nm- and 400 nm-thick gate oxide layers irradiated under the gate biases ranging from 1.25 to 5 V. Also, an exponential dependence of the radiation sensitivity on the gate bias during irradiation was found. The signal fades at room temperature without a gate bias. The results demonstrate that these RADFETs are suitable as sensors of gamma radiation. The threshold voltage shift of the RADFETs with 400 nm- and 1 μm-thick gate oxide layers decreases significantly during the first day after irradiation, which, unfortunately, makes these devices incapable of holding dosimetric information for long periods of time., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) maintains a (60)Co teletherapy source primarily for the calibration of therapy dosemeters. The source and encapsulating head were replaced in early 2010 with an Eldorado 78 head and new (60)Co source. In this article we present the results of ongoing accuracy and stability measurements since the replacement. A number of formal and informal indirect comparisons have been carried out with laboratories holding primary and secondary standards for (60)Co. ARPANSA chambers have also been calibrated at international primary standard laboratories allowing comparison of calibration coefficients and thus (60)Co absorbed dose standards. (60)Co calibration coefficients supplied by manufacturers of chambers were compared to those measured at the ARPANSA when this calibration was traceable to a primary standard. ARPANSA also participates in an annual international mailed dosimetry audit conducted by the International Atomic Energy Agency. The results thus far demonstrate that the absorbed doses to water delivered by the new ARPANSA (60)Co source are consistent with international doses within the stated uncertainties.

This paper presents a method to experimentally validate the beam quality correction factors (kQ) tabulated in IAEA TRS-398 for proton beams and to determine the kQ of non-tabulated ionization chambers (based on the already tabulated values). The method is based exclusively on ionometry and it consists in comparing the reading of two ionization chambers under the same reference conditions in a proton beam quality Q and a reference beam quality (60)Co. This allows one to experimentally determine the ratio between the kQ of the two ionization chambers. In this work, 7 different ionization chamber models were irradiated under the IAEA TRS-398 reference conditions for (60)Co beams and proton beams. For the latter, the reference conditions for both modulated beams (spread-out Bragg peak field) and monoenergetic beams (pseudo-monoenergetic field) were studied. For monoenergetic beams, it was found that the experimental kQ values obtained for plane-parallel chambers are consistent with the values tabulated in IAEA TRS-398; whereas the kQ values obtained for cylindrical chambers are not consistent--being higher than the tabulated values. These results support the suggestion (of previous publications) that the IAEA TRS-398 reference conditions for monoenergetic proton beams should be revised so that the effective point of measurement of cylindrical ionization chambers is taken into account when positioning the reference point of the chamber at the reference depth. For modulated proton beams, the tabulated kQ values of all the ionization chambers studied in this work were found to be consistent with each other--except for the IBA FC65-G, whose experimental kQ value was found to be 0.6% lower than the tabulated one. The kQ of the PTW Advanced Markus chamber, which is not tabulated in IAEA TRS-398, was found to be 0.997 ± 0.042 (k = 2), based on the tabulated value of the PTW Markus chamber.

The authors report the results of an indirect comparison of the standards of absorbed dose to water in high-energy photon beams from a clinical linac and (60)Co radiation beam performed between the National Metrology Institute of Japan (NMIJ) and the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA). Three ionisation chambers were calibrated by the NMIJ in April and June 2013 and by the ARPANSA in May 2013. The average ratios of the calibration coefficients for the three ionisation chambers obtained by the NMIJ to those obtained by the ARPANSA were 0.9994, 1.0040 and 1.0045 for 6-, 10- and 15-MV (18 MV at the ARPANSA) high-energy photon beams, respectively. The relative standard uncertainty of the value was 7.2 × 10(-3). The ratio for (60)Co radiation was 0.9986(66), which is consistent with the results published in the key comparison of BIPM.RI(I)-K4., (© The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Whole-body counters (WBCs) are generally used for monitoring internal radioactive contamination of radiation workers in nuclear power plants. However, it has been found that external contamination is occasionally counted as internal contamination. The previous study was conducted to provide guidance on measuring the exact internal radioactivity using a Canberra WBC. However, there is strong need to verify the application of the previous study to whole-body counting using a different type of WBC, ORTEC StandFAST II. Thus, in this study, several experiments were conducted focusing on the discrimination between external and internal contamination. Finally, it was found that counts from the front and back are still effective to distinguish external contamination from internal contamination for whole-body counting., (© The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Spot samples of shallow groundwaters have been taken between the years 2004 and 2010 near a site formerly used for the dispersal of radioactive liquid wastes. Three sampling points, one clean (upstream), and two downstream of the contamination source, were processed by ultrafiltration (5000 Da cut-off) and Solid Phase Extraction (SPE) to determine the association of selected artificial radionuclides ((60)Co, (137)Cs) with Natural Organic Matter (NOM). The last two sampling episodes (2008 and 2010) also benefited from fluorescence analysis to determine the major character of the NOM. The fluorescence signals are reported as humic-like, fulvic-like and protein-like, which are used to characterize the different NOM types. The NOM from the clean site comprised mostly fine material, whereas the colloidal content (retained by ultrafiltration) was higher (e.g., 15-40% of the Total Organic Carbon - TOC). Most of the 137Cs was present in the colloidal fraction, whereas (60)Co was found in the filtered fraction. Fluorescence analysis, on the other hand, indicated a contrasting behavior between the clean and contaminated sites, with a dominance of protein-like material, a feature usually associated with human impacts. Finally, SPE removed almost quantitatively the protein-like material (>90%), whereas it removed a much smaller fraction of the (137)Cs (<28%). This finding indicates that the (137)Cs preferential binding occurs with a fraction other than the protein-like NOM, likely the fulvic-like or humic-like portion., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) maintains the Australian primary standard of absorbed dose. Until recently, the standard was used to calibrate ionisation chambers only in (60)Co gamma rays. These chambers are then used by radiotherapy clinics to determine linac output, using a correction factor (k Q) to take into account the different spectra of (60)Co and the linac. Over the period 2010-2013, ARPANSA adapted the primary standard to work in megavoltage linac beams, and has developed a calibration service at three photon beams (6, 10 and 18 MV) from an Elekta Synergy linac. We describe the details of the new calibration service, the method validation and the use of the new calibration factors with the International Atomic Energy Agency's TRS-398 dosimetry Code of Practice. The expected changes in absorbed dose measurements in the clinic when shifting from (60)Co to the direct calibration are determined. For a Farmer chamber (model 2571), the measured chamber calibration coefficient is expected to be reduced by 0.4, 1.0 and 1.1 % respectively for these three beams when compared to the factor derived from (60)Co. These results are in overall agreement with international absorbed dose standards and calculations by Muir and Rogers in 2010 of k Q factors using Monte Carlo techniques. The reasons for and against moving to the new service are discussed in the light of the requirements of clinical dosimetry.

Beam quality correction, kQQ0(r), for solid-state detectors diamond, LiF, Li2B4O7, Al2O3, and plastic scintillator are calculated as a function of distance, r, along the transverse axis of the 60Co and 192Ir brachytherapy sources using the Monte Carlo- based EGSnrc code system. This study also includes calculation of detector-specific phantom scatter correction, kphan(r), for solid phantoms such as PMMA, polysty- rene, solid water, virtual water, plastic water, RW1, RW3, A150, and WE210. For 60Co source, kQQ0(r) is about unity and distance-independent for diamond, plastic scintillator, Li2B4O7 and LiF detectors. For this source, kQQ0(r) decreases gradually with r for Al2O3 detector (about 6% smaller than unity at 15 cm). For 192Ir source, kQQ0(r) is about unity and distance-independent for Li2B4O7 detector (overall variation is about 1% in the distance range of 1-15 cm). For this source, kQQ0(r) increases with r for diamond and plastic scintillator (about 6% and 8% larger than unity at 15 cm, respectively). Whereas kQQ0(r) decreases with r gradually for LiF (about 4% smaller than unity at 15 cm) and steeply for Al2O3 (about 25% smaller than unity at 15 cm). For 60Co source, solid water, virtual water, RW1, RW3, and WE210 phantoms are water-equivalent for all the investigated solid-state detectors. Whereas polystyrene and plastic water phantoms are water-equivalent for diamond, plastic scintillator, Li2B4O7 and LiF detectors, but show distance-dependent kphan(r) values for Al2O3 detector. PMMA phantom is water-equivalent at all distances for Al2O3 detector, but shows distance-dependent kphan(r) values for remaining detec- tors. A150 phantom shows distance-dependent kphan(r) values for all the investigated detector materials. For 192Ir source, solid water, virtual water, RW3, and WE210 phantoms are water-equivalent for diamond, plastic scintillator, Li2B4O7 and LiF detectors, but show distance-dependent kphan(r) values for Al2O3 detector. All other phantoms show distance-dependent kphan(r) values for all the detector materials.

Tissue-equivalent proportional counters (TEPCs) are widely used in experimental microdosimetry for characterising the radiation quality in radiation protection and radiation therapy environments. Generally, TEPCs are filled with tissue-equivalent gas mixtures, at low gas pressure, to simulate tissue site sizes similar to the cell nucleus (1 or 2 µm). The TEPC response using Monte Carlo (MC) codes can be applied to supplement experimental measurements. Most of general-purpose MC codes currently available recourse to the condensed-history approach to model the electron transport and do not transport low-energy electrons (<1 keV), which can lead to systematic errors, especially in thin layers and in gas-condensed medium interfaces. In this work, a comparison between experimental microdosimetric spectra of (60)Co and (137)Cs radiation at different simulated sizes (from 1.0 to 3.0 μm) in pure propane versus simulated spectra obtained with two general-purpose codes FLUKA and PENELOPE, which include a detailed simulation of electron-photon transport in arbitrary materials, including gases, is presented., (© The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Purpose: More than 10,000 Taiwanese people were exposed to excessive protracted low-dose rate radiation from contaminated reinforcement bars, which were installed in buildings before 1992. This study was conducted to assess the prevalence of depression amongst the exposed and identify related determinants now that more than two decades have passed since this population was informed of their exposure to radiation., Materials and Methods: We used the Beck depression inventory (BDI)-1A questionnaire to survey 2143 eligible people during their annual physical examinations between March 2009 and December 2009. In total, 1621 people participated in the survey. We employed multivariate logistic regression models with generalized estimating equations method to identify the determinants of depression., Results: The prevalence of depression (BDI-IA score ≥ 12) was 18.7%. Those who exhibited higher cumulative exposure [adjusted odds ratio (OR): 1.46, 95% confidence interval (CI): 1.02-2.07] and a previous history of depression (adjusted OR: 2.49, 95% CI: 1.36-4.58) were significantly associated with the risk of depression, whereas education level was inversely related to depression (adjusted OR: 0.71, 95% CI: 0.50-0.99)., Conclusion: Long-term, low-dose rate radiation exposure early in life might cause subsequent psychological stress and an increased risk of depression decades later.

A severe radiation accident occurred on 14 June 2011 in an industrial irradiation facility for medical equipment sterilization in Bulgaria. Five people were exposed for 5-10 min to a 60Co source containing 137 TBq. The Emergency Department of the National Centre of Radiobiology and Radiation Protection (NCRRP), Bulgaria, put into practice the plans for providing medical care in radiation accidents and the procedures developed for assessment of injury severity, the decision-making algorithm regarding subsequent treatment, and the therapy for persons affected. The activities performed for initial assessment of the severity of injury of irradiated patients were published in 2012. Based on predictive assessments of the severity of radiation damage, it was decided that the victims required hospitalization at a specialized hematology clinic. Percy Hospital in Paris was chosen for this purpose. The aim of this report is to present the results of 1-y follow-up for three of the victims. Sadly, 1 mo after the accident, Patient 4 died from a heart attack. The medical opinion was that this was not a direct outcome of the irradiation. Patient 5 was only followed up for 4 mo (118 d) because medical follow-up is voluntary, and despite repeated calls, the patient did not respond. Medical examinations by a physician as well as hematology and biochemical tests were performed using standard laboratory methods. The obtained results were compared to the victims' personal reference limits obtained from annual health monitoring. After the accident, the recovery to normal content of peripheral blood cells was observed in all victims. Nevertheless, there were observed cases of thrombocytopenia, granulocytopenia, and leucocytopenia at various times after exposure. During the period of observation, morphological changes in red blood cells such as anisomicrocitosis, macrocytes, megalocytes, and polychromatic erythrocytes were demonstrated. During the 1-y observation period, all victims showed immediate hematopoietic recovery within 2 mo after irradiation. Slight hypocellularity of bone marrow was noted at the end of the year.

Quality control (QC) detects changes in the performance of gamma cameras that could adversely affect interpretations of clinical studies. We used plate and sheet (57)Co flood sources to measure extrinsic uniformity during daily QC. Each source, when placed on the top of a collimated detector, allowed the acquisition of uniform images from both detectors, thus reducing the amount of time needed to perform daily QC. No serious problems with the gamma camera system were revealed by visual checks, and changes in detector sensitivity were rapidly determined by observing daily variations in the measured values of extrinsic uniformity. Furthermore, (57)Co flood sources confer advantages in that they shorten the time required for preparation of flood sources and reduce the consequent exposure of medical staff to radiation.

Danube water, sediment and various aquatic organisms (snail, mussel, predatory and omnivorous fish) were collected upstream (at a background site) and downstream of the outlet of the warm water channel of Paks Nuclear Power Plant. Gamma emitters, tissue free-water tritium (TFWT) and total organically-bound tritium (T-OBT) measurements were performed. A slight contribution of the power plant to the natural tritium background concentration was measured in water samples from the Danube section downstream of the warm water channel. Sediment samples also contained elevated tritium concentrations, along with a detectable amount of (60)Co. In the case of biota samples, TFWT exhibited only a very slight difference compared to the tritium concentration of the Danube water, however, the OBT was higher than the tritium concentration in the Danube, independent of the origin of the samples. The elevated OBT concentration in the mollusc samples downstream of the warm water channel may be attributed to the excess emission from the nuclear power plant. The whole data set obtained was used for dose rate calculations and will be contributed to the development of the ERICA database., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Recent developments have seen the expansion of the system of radiological protection for humans to one including protection of the environment against detrimental effects of radiation exposure, although a fully developed framework for integration of human and ecological risk assessment for radionuclides is only at an early stage. In the context of integration, significant differences exist between assessment methodologies for humans and the environment in terms of transfer, exposure, and dosimetry. The aim of this elaboration was to explore possible implications of the simplifications made within the system of environmental radiological protection in terms of the efficacy and robustness of dose-rate predictions. A comparison was conducted between human radiological assessment and environmental radiological assessment for an anthropomorphic surrogate, the results for which, produced by both the environmental and human-oriented risk assessment systems, were critically compared and contrasted. The adopted approach split the calculations into several parts, these being 1) physical transfer in an ecosystem, 2) transfer to humans, 3) internal doses to humans, and 4) external doses to humans. The calculations were carried out using both a human radiological assessment and ecological risk assessment system for the same surrogate. The results of this comparison provided indications as to where the 2 systems are amenable to possible integration and where such integration may prove difficult. Initial stage transport models seem to be an obvious component amenable for integration, although complete integration is arguably unattainable as the differences between endpoints mean that the relevant outputs from the models will not be the same. For the transfer and dosimetry components of 2 typical methodologies, it seems that the efficacy of the environmental system is radionuclide-dependent, the predictions given by the environmental system for (90) Sr and (60) Co being unsatisfactory and those for (239) Pu and (210) Po being evidently poor. Integration in this context might take the form of exploring the biokinetic models developed for humans with regard to selected animals and radionuclides. External dose assessment for environmental and human systems provide results for the surrogate that correspond quite closely providing an indication that integration in this regard is perhaps unnecessary., (© 2013 SETAC.)

The radiological characterisation of nuclear waste is essential for managing storage sites. Determining the concentration of Long-Lived RadioNuclides (LLRN) is fundamental for their long-term management. This paper focuses on the measurement of low (41)Ca concentrations in ions exchange resins used for primary fluid purification in Pressurised Water Reactors (PWR). (41)Ca concentrations were successfully measured by Accelerator Mass Spectrometry (AMS) after the acid digestion of resin samples, followed by radioactive decontamination and isobaric suppression through successive hydroxide, carbonate, nitrate and final CaF2 precipitations. Measured (41)Ca concentrations ranged from 0.02 to 0.03 ng/g, i.e. from 0.06 to 0.09 Bq/g. The (41)Ca/(60)Co activity ratios obtained were remarkably reproducible and in good agreement with the current ratio used for resins management., (© 2013 Elsevier Ltd. All rights reserved.)

Measurements for internal dose assessment are required to be conducted based on the distribution of radionuclides in the body, which may change depending on the lapsed time. In this study, a biokinetic analysis code, which can be used in practical radiation control is developed, and the results of (60)Co and (137)Cs biokinetics are visualised as examples by drawing the depositions for each organ and tissue in a figure of the body as a function of lapsed time. In addition, based on visualised biokinetics, precautions for in vivo measurements are also discussed. These discussions led to the conclusion that the information of visualised biokinetics is useful for actual measurements in practical radiation control.

In this work a method for the evaluation of the activity when a point source containing (60)Co is located in an unknown position within a sample is developed. The method can be applied if the count rate in the 2,505 keV sum peak has an acceptable uncertainty. It is based on the correlation between the apparent efficiency for the 1,173 keV peak and the ratio of the count rate in the sum peak of 2,505 keV and in the 1,332 keV peak. The correlation was observed in the measurements of a (60)Co point source located in various positions in a soil sample. The measurements were done with a 47% efficiency n-type HPGe detector. The correlation is also observed in the measurements and simulations done with a Compton-suppressed spectrometer having a 100% n-type HPGe detector. The results obtained with the proposed method are less affected by the uncertainty of the position of the point source than the results obtained using the standard methods of activity evaluation., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Kinetics of (137)Cs, (60)Co and (85)Sr sorption on powdered building materials in aqueous suspensions at 20 °C for interaction times of 1, 7, 14 and 28 days were studied. The (137)Cs distribution coefficient (Kd) values for all building materials except limestone practically did not change during 28 days of sorption. The Kd ((85)Sr) was several orders of magnitude lower than for (60)Co. The highest values were observed for asphalt and granite. An effective method to study the radionuclide distribution in depth of building materials using layer-by-layer sanding was developed. Using the developed method, the (137)Cs, (60)Co and (85)Sr distribution with depth of selected building materials at different air humidity, time and temperature was studied. Relative humidity (RH) was found to influence significantly the (85)Sr depth distribution in the case of granite (unlike (137)Cs and (60)Co). While (85)Sr penetrated to 0.5 mm in depth of granite at RH 30%, at RH 87% the depth of (85)Sr penetration to granite reached up to 7 mm., (Copyright © 2013 Elsevier Ltd. All rights reserved.)