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International Journal of Environmental... Jul 2022We "bathe" in radiation, which is an integral part of our environment [...].
We "bathe" in radiation, which is an integral part of our environment [...].
Topics: Air Pollutants, Radioactive; Air Pollution, Indoor; Environmental Monitoring; Housing; Radiation Monitoring; Radioactivity; Radon
PubMed: 35954633
DOI: 10.3390/ijerph19159276 -
Molecules (Basel, Switzerland) Feb 2023With the wide application of nuclear energy, the problem of radioactive pollution has attracted worldwide attention, and the research on the treatment of radioactive... (Review)
Review
With the wide application of nuclear energy, the problem of radioactive pollution has attracted worldwide attention, and the research on the treatment of radioactive wastewater is imminent. How to treat radioactive wastewater deeply and efficiently has become the most critical issue in the development of nuclear energy technology. The radioactive wastewater produced after using nuclear technology has the characteristics of many kinds, high concentration, and large quantity. Therefore, it is of great significance to study the treatment technology of radioactive wastewater in reprocessing plants. The process flow and waste liquid types of the post-treatment plant are reviewed. The commonly used evaporation concentration, adsorption, precipitation, ion exchange, biotechnology, membrane separation, and photocatalysis are summarized. The basic principles and technological characteristics of them are introduced. The advantages and disadvantages of different single and combined processes are compared, and the development trend of future processing technology is prospected.
Topics: Wastewater; Water Purification; Nuclear Energy; Radioactivity; Biotechnology
PubMed: 36838922
DOI: 10.3390/molecules28041935 -
PloS One 2022Northern Sweden has been the object of intense metal mining in the last decades producing several water-filled open-pits, or pit lakes. Most of these pit lakes have been...
Northern Sweden has been the object of intense metal mining in the last decades producing several water-filled open-pits, or pit lakes. Most of these pit lakes have been limed to maintain a good water quality and to prevent generation of acidic water that could leach the exposed rocks and release metals into water. The aim of this work was to examine the concentration of stable elements and naturally occurring radionuclides in water and sediment samples from pit lakes originating from non-uranium mining activities in Northern Sweden. Surface water and surface sediments were collected from 27 pit lakes in Northern Sweden. Water quality parameters, concentration of stable elements and radionuclides were measured by a water probe, ICP-MS and XRF, and alpha and gamma spectrometry, respectively. Furthermore, a multivariate statistical analysis (PCA) was performed on the water samples and sediments. In general, the quality of the surface water was good, but some lakes had low pH values (2.5-5.7), and high concentrations of Fe (up to 200 mg/L) and other metals (e.g. Zn, Cu). When relating the metal concentrations in sediments in pit lakes with the concentration found in natural lakes, some sites had relatively high levels of Cu, As, Cr and Pb. The activity concentration of 210Po, and U and Th isotopes in water and sediment samples were at environmental levels, as was the ambient dose equivalent rate at these sites (range 0.08-0.14 μSv/h).
Topics: Environmental Monitoring; Geologic Sediments; Lakes; Metals, Heavy; Polonium; Radioactivity; Radioisotopes; Sweden; Water Pollutants, Chemical
PubMed: 35358244
DOI: 10.1371/journal.pone.0266002 -
Scientific Reports Jul 2023Plants absorb water, nutrients and minerals from the soil through their root. Also, minerals, the radionuclides present in the growing media also are absorbed by plant...
Plants absorb water, nutrients and minerals from the soil through their root. Also, minerals, the radionuclides present in the growing media also are absorbed by plant parts following the same pathway. Consequently, it is important to determine the concentrations of these radionuclides in edible plants to access the associated risk to human health. In the present work, the levels of natural radioactivity and the level of some toxic elements in 17 medicinal plants, commonly used in Egypt, were measured using high-purity germanium gamma spectrometry and atomic absorption, respectively. The investigated plants were sub-grouped according to the edible parts into leave samples (n = 8), roots (n = 3), and seeds (n = 6). Also, the specific activity of both radon and thoron was measured by using alpha emitters registration which is emitted from radon and thoron gases in CR-39 nuclear track detectors. Additionally, the concentration of some toxic elements (Cu, Zn, Cd and, Pb) in six samples of medicinal plants was determined by atomic absorption spectrometry.
Topics: Humans; Plants, Medicinal; Metals, Heavy; Radioactivity; Radon; Radioisotopes; Minerals
PubMed: 37414833
DOI: 10.1038/s41598-023-37403-7 -
Frontiers in Public Health 2021The radioactivity induced by proton and heavy ion beam belongs to the ultra-low-activity (ULA). Therefore, the radioactivity and space range of commercial off-line...
The radioactivity induced by proton and heavy ion beam belongs to the ultra-low-activity (ULA). Therefore, the radioactivity and space range of commercial off-line positron emission tomography (PET) acquisition based on ULA should be evaluated accurately to guarantee the reliability of clinical verification. The purpose of this study is to quantify the radioactivity and space range of off-line PET acquisition by simulating the ULA triggered by proton and heavy ion beam. PET equipment validation phantom and low activity F-FDG were used to simulate the ULA with radioactivity of 11.1-1480 Bq/mL. The radioactivity of ULA was evaluated by comparing the radioactivity in the images with the values calculated from the decay function with a radioactivity error tolerance of 5%. The space range of ULA was evaluated by comparing the width of the R50 analyzed activity distribution curve with the actual width of the container with a space range error tolerance of 4 mm. When radioactivity of ULA was >148 Bq/mL, the radioactivity error was <5%. When radioactivity of ULA was >30 Bq/mL, the space range error was below 4 mm. Off-line PET can be used to quantify the radioactivity of proton and heavy ion beam when the ULA exceeds 148 Bq/mL, both in radioactivity and in space range.
Topics: Carbon; Positron-Emission Tomography; Protons; Radioactivity; Reproducibility of Results
PubMed: 34938708
DOI: 10.3389/fpubh.2021.771017 -
The Science of the Total Environment Jan 2022A considerable amount of data has been published on the accumulation of radiocaesium (Cs and particularly, Cs) in wild fungi since the first anthropogenically influenced... (Review)
Review
A considerable amount of data has been published on the accumulation of radiocaesium (Cs and particularly, Cs) in wild fungi since the first anthropogenically influenced releases into the environment due to nuclear weapon testing, usage and subsequently from major accidents at nuclear power plants in Chernobyl (1986) and Fukushima (2011). Wild fungi are particularly susceptible to accumulation of radiocaesium and contamination persists for decades after pollution events. Macromycetes (fruiting bodies, popularly called mushrooms) of the edible fungal species are an important part of the human and forest animal food-webs in many global locations. This review discusses published occurrences of Cs and Cs in twenty four species of Tricholoma mushrooms sourced from the Northern Hemisphere over the last five decades, but also includes some recent data from Italy and Poland. Tricholoma are an ectomycorrhizal species and the interval for contamination to permeate to lower soils layers which host their mycelial networks, results in a delayed manifestation of radioactivity. Available data from Poland, over similar periods, may suggest species selective differences in accumulation, with some fruiting bodies, e.g. T. portentosum, showing lower activity levels relative to others, e.g. T. equestre. Species like T. album, T. sulphurescens and T. terreum also show higher accumulation of radiocaesium, but reported observations are few. The uneven spatial distribution of the data combined with a limited number of observations make it difficult to decipher any temporal contamination patterns from the observations in Polish regions. When data from other European sites is included, a similar variability of Cs activity is apparent but the more recent Ukrainian data appears to show relatively lower activities. K activity in mushrooms which is associated with essential potassium, remains relatively constant. Further monitoring of Cs activity in wild mushrooms would help to consolidate these observations.
Topics: Agaricales; Cesium Radioisotopes; Humans; Mycorrhizae; Poland; Radioactivity; Soil; Tricholoma
PubMed: 34464794
DOI: 10.1016/j.scitotenv.2021.149829 -
Journal of Environmental Radioactivity Mar 2017
Topics: Construction Materials; Radiation Monitoring; Radioactivity
PubMed: 28110793
DOI: 10.1016/j.jenvrad.2017.01.007 -
International Journal of Environmental... Mar 2021Radon (Rn) and thoron (Rn) account for almost two-thirds of the annual average radiation dose received by the Irish population. A detailed study of natural radioactivity...
Radon (Rn) and thoron (Rn) account for almost two-thirds of the annual average radiation dose received by the Irish population. A detailed study of natural radioactivity levels and radon and thoron exhalation rates was carried out in a legislatively designated "high radon" area, as based on existing indoor radon measurements. Indoor radon concentrations, airborne radiometric data and stream sediment geochemistry were collated, and a set of soil samples were taken from the study area. The exhalation rates of radon (E) and thoron (E) for collected samples were determined in the laboratory. The resultant data were classified based on geological and soil type parameters. Geological boundaries were found to be robust classifiers for radon exhalation rates and radon-related variables, whilst soil type classification better differentiates thoron exhalation rates and correlated variables. Linear models were developed to predict the radon and thoron exhalation rates of the study area. Distribution maps of radon and thoron exhalation rates (range: E [0.15-1.84] and E [475-3029] Bq m h) and annual effective dose (with a mean value of 0.84 mSv y) are presented. For some parts of the study area, the calculated annual effective dose exceeds the recommended level of 1 mSv y, illustrating a significant radiation risk. Airborne radiometric data were found to be a powerful and fast tool for the prediction of geogenic radon and thoron risk. This robust method can be used for other areas where airborne radiometric data are available.
Topics: Air Pollutants, Radioactive; Air Pollution, Indoor; Housing; Ireland; Radiation Monitoring; Radioactivity; Radon; Soil
PubMed: 33800209
DOI: 10.3390/ijerph18052709 -
Scientific Reports Nov 2022The main objective of radiotherapy is to exploit the curative potential of ionizing radiation while inflicting minimal radiation-induced damage to healthy tissue and...
The main objective of radiotherapy is to exploit the curative potential of ionizing radiation while inflicting minimal radiation-induced damage to healthy tissue and sensitive organs. Proton beam therapy has been developed to irradiate the tumor with higher precision and dose conformity compared to conventional X-ray irradiation. The dose conformity of this treatment modality may be further improved if narrower proton beams are used. Still, this is limited by multiple Coulomb scattering of protons through tissue. The primary aim of this work was to develop techniques to produce narrow proton beams and investigate the resulting dose profiles. We introduced and assessed three different proton beam shaping techniques: (1) metal collimators (100/150 MeV), (2) focusing of conventional- (100/150 MeV), and (3) focusing of high-energy (350 MeV, shoot-through) proton beams. Focusing was governed by the initial value of the Twiss parameter [Formula: see text] ([Formula: see text]), and can be implemented with magnetic particle accelerator optics. The dose distributions in water were calculated by Monte Carlo simulations using Geant4, and evaluated by target to surface dose ratio (TSDR) in addition to the transverse beam size ([Formula: see text]) at the target. The target was defined as the location of the Bragg peak or the focal point. The different techniques showed greatly differing dose profiles, where focusing gave pronouncedly higher relative target dose and efficient use of primary protons. Metal collimators with radii [Formula: see text] gave low TSDRs ([Formula: see text]) and large [Formula: see text]([Formula: see text]). In contrast, a focused beam of conventional ([Formula: see text]) energy produced a very high TSDR ([Formula: see text]) with similar [Formula: see text] as a collimated beam. High-energy focused beams were able to produce TSDRs [Formula: see text] and [Formula: see text] around 1.5 mm. From this study, it appears very attractive to implement magnetically focused proton beams in radiotherapy of small lesions or tumors in close vicinity to healthy organs at risk. This can also lead to a paradigm change in spatially fractionated radiotherapy. Magnetic focusing would facilitate FLASH irradiation due to low losses of primary protons.
Topics: Proton Therapy; Protons; Monte Carlo Method; Particle Accelerators; Radioactivity; Radiotherapy Dosage
PubMed: 36344543
DOI: 10.1038/s41598-022-22677-0 -
Journal of Nuclear Medicine Technology Mar 2020F-fluciclovine PET is approved for prostate cancer recurrence imaging. According to the radiopharmaceutical package insert, only 3% of the tracer is expected to be...
F-fluciclovine PET is approved for prostate cancer recurrence imaging. According to the radiopharmaceutical package insert, only 3% of the tracer is expected to be excreted in the urine over the first 4 h. Yet, in clinical practice we noticed a higher percentage of bladder excretion. We sought to evaluate and quantify early F-fluciclovine bladder radioactivity and determine whether refraining from voiding before F-fluciclovine injection would mitigate it. In total, 159 patients underwent F-fluciclovine PET/CT imaging as part of their clinical workup. The first 36 patients were instructed to void just before F-fluciclovine injection; the subsequent 123 patients were not asked to void. The SUV and SUV of the bladder, aorta, marrow, liver, and bladder volumes were determined. Comparing SUV of bladder to background, we characterized bladder radioactivity as insignificant (bladder < aorta), mild (bladder > aorta < marrow), moderate (bladder > marrow < liver), or intense (bladder > liver). Differences between the protocols were investigated. Overall, 22% (35/159) of patients had moderate bladder activity and 8.8% (14/159) had intense bladder activity. A negative association was found between bladder volume and SUV A significant difference was found between the voiding and nonvoiding groups, with 38.9% (14/36) versus 17.1% (21/123) of patients, respectively, having moderate bladder activity and 22.2% (8/36) versus 4.9% (6/123) of patients, respectively, having intense bladder activity. Refraining from voiding before F-fluciclovine injection results in significantly lower urinary bladder radioactivity than does purposeful voiding before injection. We have modified our practice accordingly, particularly as moderate and intense bladder activity may mask or mimic local prostate cancer recurrence. Mechanisms underlying this phenomenon should be further investigated.
Topics: Aged; Carboxylic Acids; Cyclobutanes; Humans; Male; Middle Aged; Neoplasm Recurrence, Local; Organs at Risk; Positron Emission Tomography Computed Tomography; Prostate; Prostatic Neoplasms; Radioactivity; Retrospective Studies; Urinary Bladder
PubMed: 31604898
DOI: 10.2967/jnmt.119.230581