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This article focuses on the study of Sr in the tooth tissues of Techa riverside residents 60 years after intake. The Techa River was contaminated by radioactive wastes in the 1950s. Contamination of the river system, including water, bottom sediment, floodplain soil, and grass, depended on the distance from the source of releases. Therefore, the average Sr intake was different in different settlements located downstream the river. An additional factor influencing Sr accumulation in the teeth is the rate of tissue mineralization at the time of intake which depended on the donor's age at the time of releases. Measurements of Sr concentration in various dental tissues (enamel, crown, and root dentin) of 166 teeth were performed about 60 years after the main intake using the method of thermoluminescence passive beta detection. The paper presents the current levels of tooth tissue contamination, and the tooth-to-tooth variability of Sr concentration in tooth tissues was assessed for the tissues which were matured at the time of massive liquid radioactive waste releases into the Techa River. A model describing the expected levels of Sr in matured dental tissues depending on age and intake has been elaborated for the population under study. The results obtained will be used for calculation of internal dose in enamel and for interpretation of tooth doses measured by means of the electron paramagnetic resonance method, among the population of the Techa River region. [ABSTRACT FROM AUTHOR]

A collaboration of the EURADOS working group on ‘Internal Dosimetry’ and the United States Transuranium and Uranium Registries (USTUR) has taken place to carry out an intercomparison on measurements and Monte Carlo modelling determining americium deposited in the bone of a USTUR leg phantom. Preliminary results and conclusions of this intercomparison exercise are presented here. [ABSTRACT FROM PUBLISHER]

The possibility of using a single grain OSL attachment system developed by the Riso National Laboratory (Roskilde, Denmark) for assessing the spatial distribution of radionuclides incorporated in human tissues was investigated. Detectors containing arrays of single grains of a-Al2O3:C powder (Landauer Inc., USA) were prepared using aluminium discs (diameter 9.7 mm), which can accommodate 100 single grains in 0.3 mm holes positioned in a 10 × 10 grid. The luminescence and dosimetric properties of each grain were investigated by exposing the detectors to uniform photon radiation fields. After the characterisation of the detectors, the systems were tested to assess the spatial dose rate distribution because of 90Sr incorporated in a tooth sample extracted from an inhabitant of the Techa River region. [ABSTRACT FROM AUTHOR]

Measurements of the response of thermoluminescent (TL) detectors after gamma ray doses high enough to observe signal saturation provide input to microdosimetric models which relate this gamma-ray response with the energy response after low doses of photons (gamma rays and low-energy X rays) and after high-LET irradiation. To measure their gamma ray response up to saturation, LiF:Mg,Ti (MTS-7 and MTT), LiF:Mg,Cu,P (MCP-7), CaSO4:Dy (KCD) and Al2O3:C detectors were irradiated with 60Co gamma rays over the range 1-5000 Gy. The X-ray photon energy response and TL efficiency (relative to gamma rays) after doses of beta rays and alpha particles, were also measured, for CaSO4:Dy and for Al2O3:C. Microdosimetric and track structure modelling was then applied to the experimental data. In a manner similar to LiF:Mg,Cu,P, the experimentally observed under response of α-Al2O3:C to X rays <100 keV, compared with cross-section calculations, is explained as a microdosimetric effect caused by the saturation of response of this detector without prior supralinearity (saturation of traps along the tracks). The enhanced X-ray photon energy response of CaSO4:Dy is related to the supralinearity observed in this material after high gamma ray doses, similarly to that in LiF:Mg,Ti. The discussed model approaches support the general rule relating dose-, energy- and ionisation density-responses in TL detectors: if their gamma ray response is sublinear prior to saturation, the measured photon energy response is lower, and if it is supralinear, it may be higher than that expected from the calculation of the interaction cross sections alone. Since similar rules have been found to apply to other solid-state detector systems, microdosimetry may offer a valuable contribution to solid-state dosimetry even prior to mechanistic explanations of physical phenomena in different TL detectors. [ABSTRACT FROM AUTHOR]

In the current study, the effects of heat treatment on the thermoluminescence (TL) and structural properties of zinc blend samples were studied. The samples were annealed after being heated for different time periods from 2 up to 10 h. The wurtzite hexagonal phase was observed upon heat treatment. It was observed that the presence of hexagonal phase with small percentage enhanced the thermoluminescence effect where the highest intensity was found to be for the sample with 8.2% wurtzite and 91.8% cubic zinc sulphide. The morphology of ZnS particles was studied by the HR-TEM analysis and it displayed an aggregated ZnS nanoparticles with almost uniform shape and size. The TL-glow curves for each sample were analysed using the Computerized Glow Curve Deconvolution (CGCD) and initial rise (IR) methods. Six trapping peaks exist between 0.98 and 1.45 eV through the deconvolution process. The number of peaks increased to 8 peaks for the fourth treatment, located between 0.95 and 1.56 eV. The activation energies and the frequency factors for getting traps were evaluated too., Competing Interests: Declarations. Competing Interests: The authors declare no competing interests., (© 2024. The Author(s).)

The current work was going to study the dosimetric properties of Egyptian muscovite minerals irradiated with β-rays using the thermoluminescence technique (TL). The analysis of the TL glow curves was done using the (T m  - T stop ) and the initial rise methods. The deconvolution of the muscovite glow curves was analyzed to have eight superimposed trapping peaks. These trapes were located at 0.72, 0.80, 0.98, 1.09, 1.19, 1.30, 1.50, and 1.59 eV. Muscovite samples were studied at doses up to 330 Gy and exhibited good linearity in relation to beta radiation. The kinetic parameters, sensitivity, and dosimetric characteristics were evaluated. High accuracy was achieved through the repeatability of TL measurements., (© 2024 John Wiley & Sons Ltd.)

In this study, the preparation and characterization of copper (Cu) and terbium (Tb) co-doped lithium borate glass using spectroscopic and thermoluminescence techniques are reported. A thermal treatment was introduced to increase the degree of crystallinity. The thermoluminescence glow curve signal of the samples displayed upon exposure to beta radiation was measured and analyzed. It was found that the samples doped with 0.1% of copper and co-doped with 0.3% terbium showed the highest thermoluminescent (TL) signal in response to the irradiated dose. The analyses revealed that the glow curves of the doped samples were composed of nine overlapping glow peaks with activation energies between 0.73 and 2.78 eV. As a whole area under the glow curve, the TL signals displayed a linear dose response in the range from 110 mGy to 55 Gy. The minimum detectible dose of the samples was found to be 10.39 µGy. It was found that peaks 1 and 2 disappear after one day of storage. The rest of the peaks (3-9) remain almost constant up to 74 days of storage., (©2023 by Radiation Research Society. All rights of reproduction in any form reserved.)

A potentially tissue-equivalent dosimeter based on lithium tetraborate co-doped with Cu and In was successfully synthesized in two steps melting process. Basic material properties were characterized using Differential scanning calorimetry, X-ray diffraction, and Fourier Transform Infrared Spectroscopy, the dosimetric properties using Thermoluminescence. The highest sensitivity was observed for dopant concentrations of 0.1% Cu and 0.5% In. Tmax-Tstop analysis revealed the existence of eight individual peaks in the composite TL glow curve, which was confirmed by computerized glow curve deconvolution. A linear dose-response was seen up to about 30 Gy, for higher doses saturation effects occurred. The minimum detectable dose was estimated at about 670 μGy. TL peaks, with peak temperature above 150 °C faded to values between 3.3 and 14.9% of the respective of initial values after 70 days storage., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Background: Radiotherapy is one of the most significant treatment modality of head and neck cancers. However, it has various hazards on the normal tissues in the radiation field. One of these affected tissues is the lingual mucosa with their papillae such as circumvallate papilla. The effects of radiation on the lingual specialized mucosa may be represented by radiation-induced mucositis and taste alteration including partial or complete loss of taste., Objectives: The aim of the study was to evaluate the dose-dependent response of circumvallate papillae to gamma radiation by immunohistochemical expression of caspase-3., Material and Methods: Twenty-four adult male albino rats were divided into 3 equal groups irradiated at 2.0, 4.0 and 6.0 Gy whole-body gamma radiation doses. Six non-irradiated rats were used as the control group. The radiation effects on circumvallate papillae were evaluated three days after irradiation via histomorphometric investigation of the papillary size and taste buds' distortion in addition to an immunohistochemical assessment of the apoptotic activity using Caspase-3 marker., Results: Dose-related changes were observed in the circumvallate papillae size and morphology and taste buds affection. The changes were obviously detected in rats irradiated at 4 Gy and 6 Gy doses. The detection of caspase-3 marker was evident in a dose-dependent manner in all the irradiated groups, more noticeably in the taste bud cells., Conclusions: It could be concluded that circumvallate papillae are adversely affected in a dose-dependent manner by gamma radiation particularly in 4 Gy and 6 Gy doses., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 The Authors.)

In this study, thermoluminescence detectors (TLD)-600 and TLD-700 were used under different conditions to study neutron dosimetry for its application in medical dosimetry as albedo dosimeters. 6 LiF has a high cross-section for neutrons and is more sensitive to neutrons than to gamma radiation. Conversely, TLD-700 showed a better response to gamma radiation. Therefore, to obtain the response for neutrons, the responses for TLD-600 and TLD-700 were subtracted. A cadmium sheet was used to absorb incident thermal neutrons so that detector measured only backscattered neutrons from the albedo dosimeter. A Perspex sheet was used as a moderator to thermalize the fast neutron source Am-Be used in the experiment. CR-39 was used to detect fast neutrons and act as an albedo dosimeter when covered with a 10 B disc. Both TLD and CR-39 dosimeters were successful in detecting scattered neutrons in radiotherapy rooms., (© 2021 John Wiley & Sons, Ltd.)

Characterization of thermoluminescence (TL) properties of lithium borate glass samples doped with different concentrations of dysprosium (Dy) was carried out. Samples were prepared using a melting method at 1100°C and irradiated with β-particles. The glass samples doped with 0.1% Dy displayed the best TL dosimetric properties compared with other compositions. Deconvoluted analyses of the glow curves displayed five overlapping TL glow peaks located between 392.0 and 510.3 K. A good linear TL dose-response for β-particles was obtained in the dose range 66.6 mGy to 33.3 Gy. The minimum detectible dose was evaluated to be 205.4 μGy and samples revealed thermal fading in 312 h to 29% of their original value., (© 2020 John Wiley & Sons, Ltd.)

The current study investigated the thermoluminescence (TL) properties of milky quartz samples collected from the Central Eastern Desert, Egypt. The crystallinity and the elemental concentrations of the milky quartz samples were examined using X-ray diffraction and an atomic absorption spectrometer. Samples were irradiated using a gamma source at different doses from 250 mGy up to 2 kGy. For annealing, the samples were heated at 400°C for 1 h, followed by slow cooling. Kinetic analyses for the TL glow curves were performed using new designed TL deconvolution software. The glow curves were composed of six overlapped trapping sites at 428, 468, 498, 545, 586, and 639 K. The samples also displayed a linear dose-response from 0.25 Gy up to 20 Gy and a supralinear response from 20 Gy up to 200 Gy. The samples exhibited very low sensitivity for gamma radiation compared with LiF and the minimum detectable dose was 545 μGy. From its linear nature, it was observed that the sensitivity had changed. This study recommends starting measurements of these milky quartz samples after 4 days to give established measurements., (© 2020 John Wiley & Sons, Ltd.)

The current study characterizes and analyzes glow curves obtained from phosphate glass doped with different concentrations of lanthanum. Kinetic parameters of the glow curves obtained from beta-irradiated phosphate glass samples doped with lanthanum were determined using a newly designed deconvoluted software. The obtained results from the analyses indicated that the glow curves of the phosphate glass samples were composed of five overlapping peaks. The activation energies of the five electron traps were located between 0.622 and 1.133 eV. The obtained kinetic parameters were evaluated using the designed software and another two methods and all revealed good agreement. The first three traps displayed non-first-order behaviour, while the two deep traps obeyed nearly first-order kinetics., (© 2019 John Wiley & Sons, Ltd.)

Two people were exposed to and contaminated with 241 Am. In vivo determinations of the incorporated 241 Am were performed using a whole-body counter and two partial-body counters for the skull and lung, respectively. Additionally, urine samples were analysed to estimate the systemic activity removed from the body. To improve the geometry of the skull measurements, an optimised detector configuration was used, a calibration with three physical phantoms of the human head was conducted, and the morphological variability between the individuals was also considered. The results of the measurements indicate that activity is not deposited in the deep tissues, rather in the skin tissues close to the body surface. Unfortunately, the many open questions relating to the actual circumstances during and after the incident make the interpretation of this case difficult if at all possible.

The present work aims at studying the effect of gamma radiation on the hard dental tissues. Eighty adult male albino rats with weights of about 250 g were used. The rats were irradiated at 0.2, 0.5, 1.0, 2.0, 4.0 and 6.0 Gy whole-body gamma doses. The effects on hard dental tissue samples were investigated after 48 h in histological and ground sections using light microscopy. Areas of acid phosphatase activity were detected using tartrate-resistant acid phosphatase (TRAP) stains. Observation of histological sections revealed disturbance in predentin thickness and odontoblastic layer as the irradiation dose increased. In cementum, widened cementocytes lacunae were occasionally detected even with low irradiated doses. On the other hand, relatively homogenous enamel was detected with darkened areas in enamel surface at doses over than 0.5 Gy. TRAP-positive cells were detected on the surface of the dentin of irradiated groups as well as cementum surface. Minimal detectable changes were observed in ground sections.

The distribution of natural nuclide gamma-ray activities and their respective annual effective dose rates, produced by potassium-40 (⁴⁰K), uranium-238 (²³⁸U), thorium-232 (²³²Th), and radium-226 (²²⁶Ra), were determined for 14 oilfield scale samples from the Middle East. Accumulated radioactive materials concentrate in tubing and surface equipment, and workers at equipment-cleaning facilities and naturally occurring radioactive materials (NORMs) disposal facilities are the population most at risk for exposure to NORM radiation. Gamma-spectra analysis indicated that photo-gamma lines represent the parents of 10 radioactive nuclides: ²³⁴Th, plutonium-239, actinium-228, ²²⁶Ra, lead-212 (²¹²Pb), ²¹⁴Pb, thallium-238 (²⁰⁸Tl), bismuth-212 (²¹²Bi), ²¹⁴Bi, and ⁴⁰K. These nuclides represent the daughters of the natural radioactive series ²³⁸U and ²³²Th with ⁴⁰K as well. The mean activity concentration of ²³⁸U, ²³²Th, and ⁴⁰K were found to be 25.8 ± 11.6, 18.3 ± 8.1, and 4487.2 ± 2.5% Bq kg⁻¹ (average values for 14 samples), respectively. The annual effective dose rates and the absorbed doses in air, both indoor and outdoor, for the samples were obtained as well. The results can be used to assess the respective hazard on workers in the field and represent a basis for revisiting current engineering practices.

Three facilities (CIEMAT, HMGU and HML) have used their in vivo counters to compare two leg phantoms. One was commercially produced with (241)Am activity artificially added to the bone inserts. The other, the United States Transuranium and Uranium Registries' (USTUR) leg phantom, was manufactured from (241)Am-contaminated bones resulting from an intake. The comparison of the two types of leg phantoms showed that the two phantoms are not similar in their activity distributions. An error in a bone activity estimate could be quite large if the commercial leg phantom is used to estimate what is contained in the USTUR leg phantom and, consequently, a real person. As the latter phantom was created as a result of a real contamination, it is deemed to be the more representative of what would actually happen if a person were internally contaminated with (241)Am.