Radiological Incidents Research Articles

Identification of miRNA Associated with Reduced Survival after Whole-Thorax Lung Irradiation in Non-Human Primates.

Thoracic exposure to ionizing radiation can lead to delayed injuries to the heart and lung that are serious and even life-threatening. These injuries are difficult to predict since they manifest over many weeks and months. To identify noninvasive, tissue-specific biomarkers for the early detection of late radiation injury, circulating microRNA (miRNA) levels were measured in non-human primates (NHP, Macaca mulatta) that received a single exposure of whole-thorax lung irradiation (WTLI) at a dose likely to result in 20% or 75% mortality within 180 days (9.8 or 10.7 Gy). Animals were observed for 270 days after WTLI. Approximately 58% of 9.8 Gy WTLI animals (7 of 12) and 94% of 10.7 Gy WTLI animals (15 out of 16) did not survive to the primary end point. Evidence of pulmonary fibrosis/pneumonitis was observed in all animals. Animals that received 10.7 Gy WTLI experienced more severe and early-onset pneumonitis, as indicated by reduced aerated lung volume, high non-sedated respiratory rate, earlier and more frequent dexamethasone treatments, and evidence of onset of heart disease. Radiation-induced changes in the circulating miRNA profile were most prominent within the first 30 days postirradiation, before the manifestation of symptoms, and included miRNA sequences known to regulate pathways associated with pulmonary fibrosis (TGF-β/SMAD signaling) and pneumonitis/inflammation (p53 signaling). The abundance of several circulating miRNA differentially expressed at day 6 or 15, such as miR-199a-3p and miR-25-3p, correlated with statistically significant differences in survival. This study supports the hypothesis that it is feasible to use plasma miRNA profiles to identify individuals at high risk of organ-specific late radiation injury. These miRNA profiles could improve radiation oncology clinical practice and serve as biomarkers to predict who might develop late complications in the aftermath of a radiological or nuclear (RAD-NUC) incident.

DNA resistance to radiation field: forensic genotyping in a radiological incident scenario

The objective of nuclear forensic science is to link an event that involves a radioactive or nuclear material with the personal and material means that have facilitated it. This implies the collection and analysis of any physical evidence of the scene, both radioactive and nuclear material for its characterization as well as classical evidence like DNA, hair, fingerprints or blood. Collecting evidence in these circumstances can be potentially dangerous for the respondent due to the risk of radiation or radioactive contamination, so studying the stability of forensic evidence in the presence of radiation will allow taking a reasonable decision whether the probative utility that the evidence may have exceeds the dangers involved in its collection. In this context, this work addresses the resistance of classical forensic evidences to radiation. Thus, gamma post-irradiation results of DNA profiling from relevant biological samples are presented and discussed providing threshold values of radiation that, depending on the matrix, degrade DNA evidence.

Emphysematous pyelonephritis: experience at a tertiary care hospital in Bangladesh.

Emphysematous pyelonephritis (EPN) is a necrotizing infection of the renal parenchyma, collecting system and/or perinephric tissues, characterized by gas accumulation. We describe clinical, laboratory and imaging characteristics and in-hospital outcomes of patients with EPN. This retrospective observational study was carried out at BIRDEM General Hospital, Dhaka, Bangladesh between 2014 and 2020. We followed 20 patients (mean age 49.4 years; females 70%). Risk factors for EPN were diabetes mellitus (in 100%) and renal stones (in 10%). Fever, loin pain, vomiting and dysuria were common. Complications included acute kidney injury (AKI, 70%; mostly stage 1, 78.6%), hyponatraemia (55%) and bacteraemia (15%). Escherichia coli was the most common (60%) urinary isolate. Most patients (80%) had class 2 EPN, with 15% class 3B and 5% class 3A. Besides medical management, four (20%) required surgery (nephrectomy in 3). Nephrectomised patients had a higher radiological class (p = 0.032) and incidence of AKI (p = 0.034). No deaths occurred. EPN occurred predominantly in female diabetic patients, who presented with fever, loin pain, vomiting and dysuria. Two-thirds of patients had AKI and one-fifth required surgery, and there were no deaths.

Neutron Radiobiology and Dosimetry.

As the U.S. prepares for the possibility of a radiological or nuclear incident, or anticipated lunar and Mars missions, the exposure of individuals to neutron radiation must be considered. More information is needed on how to determine the neutron dose to better estimate the true biological effects of neutrons and mixed-field (i.e., neutron and photon) radiation exposures. While exposure to gamma-ray radiation will cause significant health issues, the addition of neutrons will likely exacerbate the biological effects already anticipated after radiation exposure. To begin to understand the issues and knowledge gaps in these areas, the National Institute of Allergy and Infectious Diseases (NIAID), Radiation Nuclear Countermeasures Program (RNCP), Department of Defense (DoD), Defense Threat Reduction Agency (DTRA), and National Aeronautics and Space Administration (NASA) formed an inter-agency working group to host a Neutron Radiobiology and Dosimetry Workshop on March 7, 2019 in Rockville, MD. Stakeholder interests were clearly positioned, given the differences in the missions of each agency. An overview of neutron dosimetry and neutron radiobiology was included, as well as a historical overview of neutron exposure research. In addition, current research in the fields of biodosimetry and diagnostics, medical countermeasures (MCMs) and treatment, long-term health effects, and computational studies were presented and discussed.

Evaluation of physical retrospective dosimetry methods in a realistic accident scenario: Results of a field test

The radiological incident in Cochabamba (Bolivia, 2002), where members of the general public where exposed to an unshielded Ir-192 radiation source whilst traveling on a bus was replicated here in an attempt to asses and evaluate emerging retrospective dosimetry methodologies using objects of daily life, that are either carried on or close to the human body or can be found in the vicinity of an individual. For this purpose an accidental exposure was simulated under controlled conditions in a secured area and an unshielded radioactive source was placed in the cargo compartment of a bus resembling a Radiological Exposure Device (RED). Water canisters and anthropomorphic phantoms were placed at selected seats on the bus and equipped with personal objects (mobile phones, chip cards) that had reference dosimeters attached to them. At one seat position, additional salt dosimeters and dental ceramics in the phantom were also tested. Two types of 8 h exposures were conducted: one with a source activity similar to the one in Cochabamba (0.65 TBq) and one with a stronger source (1.5 TBq) in order to have more samples with absorbed doses above the detection limit of the different methods. For 43 out of 61 resistor and glass samples from mobile phones, measured doses agreed within error limits with reference doses, but for some materials more research is needed for a more reliable application. In 13 cases outliers with a significant dose over- or underestimation were observed, 10 of these could be identified by combining the results of at least three dose assays. The field test thus evaluated the potential and limitation of retrospective dosimetry using personal objects and demonstrated the importance of using a multi-dosimeter approach to increase robustness of the method.

Facile preparation of liposome-encapsulated Zn–DTPA from soy lecithin for decorporation of radioactive actinides

Diethylenetriaminepentaacetic acid (DTPA) is an attractive decorporation agent that can enhance the excretion of radioactive actinides such as plutonium, americium, and curium after a radiological incident. However, DTPA is excreted in a short period of time after administration. Several formulations have been developed to improve DTPA pharmacokinetics properties. In this project, liposomes were prepared facilely from soy lecithin as a nanocarrier for pulmonary delivery of Zn–DTPA. Lipid hydration, reverse phase evaporation, and mechanical sonication were three methods evaluated for the preparation of liposome-encapsulated Zn-DTPA (lipo-Zn-DTPA). Mechanical sonication was the method of choice due to simple apparatus and facile preparation. Lipo-Zn–DTPA exhibited a hydrodynamic diameter of 178 ± 2 nm and a spherical shape. The loading capacity and encapsulation efficiency of Zn–DTPA were 41 ± 5 mg/g and 10% ± 1%, respectively. Lyophilization of lipo-Zn–DTPA for extended storage did not affect the amount of encapsulated drug or damage the structure of liposomes. An in vivo cytotoxicity test confirmed no serious adverse effect of Zn–DTPA encapsulated lecithin liposomes in rats.

Universal use of alpha/beta mode in liquid scintillation counting analysis for both alpha/beta and single nuclide determination

Nuclear industry advancements and growing concerns about environmental contamination and terrorist activity have increased interest in quantifying radioisotopes in environmental and human samples. Increased presence in the environment, ease of entry into the food chain, nuclear medicine applications, and the possibility of radiological terrorism incidents can lead to human intake of these radionuclides [1,2]. A universal method to screen for and quantify individual radionuclides as well as both levels of alpha and beta emitters would address these concerns.

Uncertainty evaluation for organ dose assessment with optically stimulated luminescence measurements on mobile phone resistors after a radiological incident

A radiological incident may result in members of the public being exposed to high doses of ionizing radiation. Rapid triage and a rough dose assessment is then an important component of the process of identifying people requiring immediate medical attention, supporting clinical observations and widening the scope to categorize those individuals who are potentially exposed but are pre-symptomatic. Optically stimulated luminescence on mobile phone resistors is well established in this context. Previous studies have shown good dosimetric properties and dose reconstruction protocols were optimized in the MULTIBIODOSE project (Bassinet et al., 2014).Evaluation of the full uncertainty budget and the detection limit is of fundamental importance for any personal dosimetry technique. In this work it was investigated how different factors influence the organ dose assessment with optically stimulated luminescence on mobile phone resistors, how one can correct for these, and how much they contribute to the uncertainty. The investigated factors include calibration, zero dose signal, reproducibility, dose response, fading, red light exposure, storage temperature, energy response and conversion from resistor dose to organ dose depending also on exposure scenario and mobile phone position.The uncertainty and detection limit were found to depend strongly on the delay between incident exposure and measurement and knowledge of the incident scenario. The uncertainty also depends strongly on the dose level. Detection limits of the order of 100 mGy were found, which is more than sufficient for triage. For doses around the detection limit the uncertainties related to the zero dose signal and reproducibility are dominant, while for higher doses of the order of grays the uncertainties related to fading and conversion from resistor to organ doses are dominant. For the higher doses the uncertainties are around 50% (k = 2) for known incident scenarios and up to more than 100% (k = 2) for unknown scenarios.Based on the results from this work recommendations are given to further decrease the uncertainty and detection limit for this technique.

Mayapuri Radiological Catastrophe: Good Practices and the Lessons Learnt.

Advances in the peaceful applications of ionizing radiation have brought in its wake the inevitable concern about radioactivity. Almost a decade ago, an infamous unprecedented radiological exposure incident occurred in Delhi, which has not only some positive aspects for imbibing good practices to emulate but also lessons learnt to further improvise the overall management, respectively. The Mayapuri incident at Delhi exposed the lack of awareness and laxity on the part of University of Delhi authorities in disposing of the Cobalt Irradiator, and the further insecure handling of the orphan radioactive source. Since an occurrence like this was unparalleled, it was necessary to flag all interlinked issues and put in place a technology management system that should address them. The methodology includes an in-depth discussion about the good practices and lessons learnt of the then-existing techno-legal systems and the response mechanism to the Mayapuri radiological incident from various departments of repute, both governmental as well as non-governmental. The present article attempts to intensify pragmatic approaches to proactively avert and thwart 'orphan source' incidents like the Mayapuri radiological incident, so that threat to the society is minimal, and putting in place enhanced medical preparedness measures for the management of radiation casualties caused by ignorance, negligence, incompetence, accident, or malicious intention.

Urine gross alpha/beta bioassay method development using liquid scintillation counting techniques.

In the case of a radiological or nuclear incident, valuable information could be obtained in a timely manner by using Liquid Scintillation Counting (LSC) technique through fast screening of urine samples from potentially contaminated persons. This work describes the optimization of LSC parameters on PerkinElmer (PE) Tri-Carb and Quantulus GCT series instruments to develop a rapid method for screening urine in an emergency response situation.

MODELING OF DOSE RATES IN CASE OF A RADIOLOGICAL INCIDENT AT THE IFIN-HH INTERMEDIARY GRAPHITE STORAGE

The low and intermediate level activity wastes resulted from decommissioning of the VVR-S nuclear research reactor belonging to the “Horia Hulubei” National Institute for R&D in Physics and Nuclear Engineering (IFIN-HH), are kept in an intermediary storage facility. The storage is located on the premises of the Institute near Bucharest, Romania and includes activated graphite from the reactor thermal column. In case of a very low probability hypothetical atmospheric radiological dispersal incident such as an unexpected fire, despite all the implemented safety measures, there is a certain radiological risk for the workers and general public due to potential ingestion or inhalation or contact with the radioactive aerosols released on a certain range from the storage building. For estimating the total gamma dose intake and adequate countermeasures for workers and public members, the JRODOS (Real-time On-line Decision Support) code system for off-site emergency management after nuclear accidents was used in the paper.

Heterotopic Ossification of the Vascular Pedicle after Maxillofacial Reconstructive Surgery Using Fibular Free Flap: Introducing New Classification and Retrospective Analysis.

Heterotopic ossification (HO) is one of the described phenomena after maxillofacial reconstructive surgery using fibular free flap (FFF) at the reception-site. The aim of this study was to determine the radiological incidence and form of HO along the fibular vascular pedicle as well as the rate of clinical symptoms if present. CT-scans of 102 patients who underwent jaw reconstructive surgery by using FFF from January 2005 to December 2019 were evaluated concerning the presence of HO. Subsequently, the patient files were evaluated to identify the cases with clinical signs and complications related to the presence of HO. A radiological classification of four different HO types was developed. Out of 102 patients, 29 (28.43%) presented radiological findings of HO. Clinical symptoms were recorded in 10 cases (9.8%) (dysphagia (n = 5), trismus (n = 3), bony masses (n = 2)) and from these only five (4.9%) needed surgical removal of calcified structures. HO occurs significantly in younger patients (mean 52.3 year). In maxillary reconstructions, HO was radiologically visible six months earlier than after mandibular reconstruction. Furthermore, HO is observed after every third maxilla and every fourth mandible reconstruction. This study developed for the first time a classification of four distinct HO patterns. HO types 1 and 2 were mostly observed after mandible reconstruction and type 4 predominantly after maxilla reconstruction.

On the use of retrospective dosimetry to assist in the radiological triage of mass casualties exposed to ionising radiation

The reconstruction of the Cochabamba (Bolivia) radiological incident (IAEA—International Atomic Energy Agency 2004 The Radiological Accident in Cochabamba STI/PUB/1199 (Vienna: IAEA)) was used to assess and evaluate retrospective dosimetry methodologies. For this purpose an unshielded radioactive source was placed inside a transportation vehicle (bus) resembling a radiological exposure device. External doses were assessed using water and anthropomorphic phantoms that were placed at various positions in the vehicle and equipped with both fortuitous dosimeters (chip cards, mobile phones), individual dosimeters (electronic dosimeters, thermoluminescent and optically stimulated luminescence dosimeters) and in three cases also with blood sample tubes in thermos flasks for cytogenetic methods. This paper gives a detailed description of the experimental setup, the results of the reference dosimetry, including organ dose assessment for the phantom closest to the source, and includes a compilation of the main results obtained by the retrospective dosimetry techniques. Comparison is made to the results of dose reconstruction obtained by IAEA during the response to the Cochabamba incident in 2002.

Guidelines for first responders based on results from deploying a mockup radiological dispersal device

During the past 7th Security Framework Program the European Commission funded a research project called CATO (CBRN Crisis management, Architectures, Technologies and Operational procedures) to develop a prototype decision support system for crisis management in addition to providing a suite of guidelines for first responders and incident commanders when dealing with chemical, biological, radiological or nuclear incidents. In order to derive these guidelines a proof-of-concept experiment was setup during which several passive agent (Stable CsCl) dispersions with improvised explosive devices and vehicle-borne improvised explosive devices were carried out. Each dispersion was thoroughly characterised by a number of monitoring devices, including high-volume air samplers and size-segregated air samplers. All environmental and forensic samples were collected by the UK counter terrorism police, following strict labelling and chain-of-custody protocols. The samples were analysed at the Belgian Nuclear Research Center suing the k0 method for instrumental neutron activation technique. A full consequence assessment analysis was carried out assuming that the observed concentration of Cs-133 in samples was Cs-137 instead and use was made of the specific activity of Cs-137. Due to the sensitivity of the information the European Commission classified this research. The resulted reported on in this work have been unclassified and are released to assist emergency planners and first responders to take the necessary precautions. The results indicate that, up to distances of 50 m from ground zero radiation levels will be considerable and therefore live-saving actions must be performed by fire/rescue wearing full protective gear. In addition, low-wind conditions will favor a long airborne residence time and therefore the use of full-face protective gear is a must. In order to protect first responders, a radiation protection specialist is to determine how long people can enter and remain in the contaminated area. The recovery of evidence in the case of a car-bomb will be hard or even impossible due to the high level of radioactive material remaining inside the vehicle.

Urine metabolomics based prediction model approach for radiation exposure

The radiological incidents and terrorism have demanded the need for the development of rapid, precise, and non-invasive technique for detection and quantification of exposed dose of radiation. Though radiation induced metabolic markers have been thoroughly investigated, but reproducibility still needs to be elucidated. The present study aims at assessing the reliability and reproducibility of markers using nuclear magnetic resonance (NMR) spectroscopy and further deriving a logistic regression model based on these markers. C57BL/6 male mice (8–10 weeks) whole body γ-irradiated and sham irradiated controls were used. Urine samples collected at 24 h post dose were investigated using high resolution NMR spectroscopy and the datasets were analyzed using multivariate analysis. Fifteen distinguishable metabolites and 3 metabolic pathways (TCA cycle, taurine and hypotaurine metabolism, primary bile acid biosynthesis) were found to be amended. ROC curve and logistic regression was used to establish a diagnostic model as Logit (p) = log (p/1 − p) = −0.498 + 13.771 (tau) − 3.412 (citrate) − 34.461 (α-KG) + 515.183 (fumarate) with a sensitivity and specificity of 1.00 and 0.964 respectively. The findings demonstrate the proof of concept and the potential of NMR based metabolomics to establish a prediction model that can be implemented as a promising mass screening tool during triage.

Potential Use of Environmental Biological Samples for Retrospective Electron Paramagnetic Resonance Dosimetry of Radiation Accidents

Retrospective dosimetry is one of the most important tools of accident dosimetry for environmental dose estimation when large-scale radiological incidents and nuclear mass-casualty events occur. Electron paramagnetic resonance (EPR) dosimetry is a physical method for the retrospective assessment of absorbed dose based on the measurement of stable radiation-induced radicals in materials. Different from the fast disappearance of radials in aqueous systems, the radials can persist indefinitely in some organized matrices. Therefore, environmental materials contained in creatures from sea or land can be potentially used as environmental dosimeters for a retrospective dose analysis. This study aims to assess the EPR signals of free radicals from environmental biological samples, potentially for the retrospective dose estimation. The evaluated samples involve ox bone, cyclina shell, clam shell, chitin from squid, and human tissue (enamel and fingernail). First, we dehydrate and grind these materials to the powder with different sizes. Subsequently, all materials were irradiated with different doses ranging from 5 Gy to 50 Gy using 6 MV linear accelerator, and EPR spectra of these materials were obtained from the calculation of peak-to-peak amplitudes. The dose-response curve of EPR signals versus irradiated dose for the six materials shows good linearity (R2~0.99). For the grain-size experiment, the ox bone and tooth with 0.5 mm, the chitin with 0.1 mm, and the others with 1 mm have the strongest signal. For the storage temperature experiment, the optimal temperature of storage is at −20 °C for tooth, fingernail, ox bone, and chitin, at 45 °C for clam shell and cyclina shell where the signal fading is minimal. In conclusion, the developed dose-response curves of the six materials may potentially help a fast, rough retrospective dose reconstruction under the environment when radiation accidents occur.

First person profile: C. Norman Coleman, MD: A leading radiation and medical oncologist, Dr. Coleman has worked to improve cancer prevention, treatment, and quality of life on a global level.

First person profile: C. Norman Coleman, MD: A leading radiation and medical oncologist, Dr. Coleman has worked to improve cancer prevention, treatment, and quality of life on a global level.

Cutaneous Radiation Injuries: Models, Assessment and Treatments.

Many cases of human exposures to high-dose radiation have been documented, including individuals exposed during the detonation of atomic bombs in Hiroshima and Nagasaki, nuclear power plant disasters (e.g., Chernobyl), as well as industrial and medical accidents. For many of these exposures, injuries to the skin have been present and have played a significant role in the progression of the injuries and survivability from the radiation exposure. There are also instances of radiation-induced skin complications in routine clinical radiotherapy and radiation diagnostic imaging procedures. In response to the threat of a radiological or nuclear mass casualty incident, the U.S. Department of Health and Human Services tasked the National Institute of Allergy and Infectious Diseases (NIAID) with identifying and funding early- to mid-stage medical countermeasure (MCM) development to treat radiation-induced injuries, including those to the skin. To appropriately assess the severity of radiation-induced skin injuries and determine efficacy of different approaches to mitigate/treat them, it is necessary to develop animal models that appropriately simulate what is seen in humans who have been exposed. In addition, it is important to understand the techniques that are used in other clinical indications (e.g., thermal burns, diabetic ulcers, etc.) to accurately assess the extent of skin injury and progression of healing. For these reasons, the NIAID partnered with two other U.S. Government funding and regulatory agencies, the Biomedical Advanced Research and Development Authority (BARDA) and the Food and Drug Administration (FDA), to identify state-of-the-art methods in assessment of skin injuries, explore animal models to better understand radiation-induced cutaneous damage and investigate treatment approaches. A two-day workshop was convened in May 2019 highlighting talks from 28 subject matter experts across five scientific sessions. This report provides an overview of information that was presented and the subsequent guided discussions.

Cutaneous Radiation Injuries: Models, Assessment and Treatments.

Many cases of human exposures to high-dose radiation have been documented, including individuals exposed during the detonation of atomic bombs in Hiroshima and Nagasaki, nuclear power plant disasters (e.g., Chernobyl), as well as industrial and medical accidents. For many of these exposures, injuries to the skin have been present and have played a significant role in the progression of the injuries and survivability from the radiation exposure. There are also instances of radiation-induced skin complications in routine clinical radiotherapy and radiation diagnostic imaging procedures. In response to the threat of a radiological or nuclear mass casualty incident, the U.S. Department of Health and Human Services tasked the National Institute of Allergy and Infectious Diseases (NIAID) with identifying and funding early- to mid-stage medical countermeasure (MCM) development to treat radiation-induced injuries, including those to the skin. To appropriately assess the severity of radiation-induced skin injuries and determine efficacy of different approaches to mitigate/treat them, it is necessary to develop animal models that appropriately simulate what is seen in humans who have been exposed. In addition, it is important to understand the techniques that are used in other clinical indications (e.g., thermal burns, diabetic ulcers, etc.) to accurately assess the extent of skin injury and progression of healing. For these reasons, the NIAID partnered with two other U.S. Government funding and regulatory agencies, the Biomedical Advanced Research and Development Authority (BARDA) and the Food and Drug Administration (FDA), to identify state-of-the-art methods in assessment of skin injuries, explore animal models to better understand radiation-induced cutaneous damage and investigate treatment approaches. A two-day workshop was convened in May 2019 highlighting talks from 28 subject matter experts across five scientific sessions. This report provides an overview of information that was presented and the subsequent guided discussions.

Summary and recommendations from the workshop ‘Integrating measurements and atmospheric-dispersion modelling to enhance the UK response to radiological atmospheric releases’

Effective preparedness and response to an atmospheric release following a radiological incident relies on information concerning the source, transport and eventual removal of the contaminant. A notable improvement to emergency preparedness and response in the UK to airborne releases of radiological contaminants can be achieved through the integration of information sources, in particular environmental radiological measurements and atmospheric-dispersion modelling. A one-day workshop was organised by the UK Met Office and the University of Bristol, comprising private nuclear facility operators, public bodies, academia and others, on 6 February 2020 in Bristol, UK. The workshop reviewed the current capabilities and challenges of measurements and modelling of airborne radiological contaminants and their integration, and identified improvement pathways. This memorandum provides a summary of recommendations from the workshop.