Radioecological characteristics of Siberian roe deer (Capreolus pygargus Pal., 1771) inhabiting locations of nuclear weapon tests.

This paper reports the activity concentrations of 137Cs, 90Sr, 239+240Pu, 241Am, and 3Н in the form of tritiated water (НТО) and organically bound tritium (ОBТ) in the tissues and organs of roe deer (Capreolus pygargus Pal., 1771) that inhabit the 'Degelen' test location of the Semipalatinsk Test Site. Tissues and organs were sampled from six deer by killing. The activity concentrations of specific radionuclides in the samples were measured using γ-, α-, and ß-spectrometry. The radionuclide activity concentrations in the tissues and organs showed considerable variation, for example, 0.6-170 Bq kg-1 for 137Cs and 0.3-2.8×103 Bq kg-1 for 90Sr. The activity concentrations of radionuclides in animal muscular tissue did not exceed permissible values for the meat of wild animals. The tissues and organs in the roe deer were arranged as follows in descending order of their ability to accumulate 137Cs and 90Sr: for 137Cs, muscular tissue-kidneys-lungs-spleen-heart-liver-bone tissue; for 90Sr, bone tissue-liver-lungs-muscular tissue-spleen-heart-kidneys. The activity concentrations of 241Am and 239+240Pu did not exceed the minimum detectable activity. Therefore, no quantitative values could be determined for 241Am, and the 239+240Pu activity concentration could be derived for only one sample: 0.5±0.1 Bq kg-1 (liver). The distribution pattern of these radionuclides in the tissues and organs of the roe deer could not be determined because of insufficient data. The HTO volumetric activity in the tissues and organs of the examined animals ranged from 2.6×10-2 to 77 kBq l-1; activity concentration of OBT, 3.0×10-2 to 16 kBq kg-1; and OBT-to-HTO ratios, 2.0×10-3 to 5.3×102. This ratio can serve as an indicator of how long the examined animals stay in radioactively contaminated ecosystems. Within the 'Degelen' site, the activity concentrations of 90Sr and tritium, in the form of HTO and OBT, are expected to be high in the bone tissues, soft tissues, and organs, respectively.

Anti-Ceramide ScFv Prophylaxis for First Responders to a Limited Nuclear Attack.

BACKGROUND/AIMS: After 9/11, multiple government agencies instituted programs aimed at developing medical radiation countermeasures (MRCs) for two syndromes lethal within weeks of a limited nuclear attack; the hematopoietic-acute radiation syndrome (H-ARS) and the higher-dose gastrointestinal-acute radiation syndrome (GI-ARS). While re-purposing drugs that enhance marrow repopulation treats H-ARS, no mitigator protects GI tract. METHODS: We recently reported anti-ceramide 6B5 single-chain variable fragment (scFv) pre-treatment abrogates ongoing small intestinal endothelial apoptosis to rescue Lgr5+ stem cells, preventing GI-ARS lethality in C57B/L6J mice. Here, with US Department of Defense support, we provide evidence that humanized anti-ceramide scFv (CX-01) is a promising prophylactic MRC for first responders, who risk exposure upon entering a radiation-contaminated site. RESULTS: CX-01, when delivered up to 90 min before irradiation, is highly-effective in preventing small intestinal endothelial apoptosis in mice and lethality in both sexes. Unexpectedly, females require an ~2-fold higher CX-01 dose than males for full protection. CX-01 is effective subcutaneously and intramuscularly, a property critical for battlefield use. Increasing the maximally-effective dose 5-fold does not extend duration of bioeffectiveness. CONCLUSION: While CX-01 prevents GI-ARS lethality, structural modification to extend half-life may be necessary to optimize first responder prophylaxis.

Research on the influencing factors of radionuclide fractionation in surface nuclear explosions.

Fractionation plays an important role in the distribution of radioactive isotopes on particles formed in a nuclear explosion. This study examines the variables that affect radionuclide fractionation in surface nuclear explosions, including nuclear explosion yield, nuclear charge, solidification temperature, solidification time, and geological condition. The distribution of radionuclides is calculated using the improved Freiling radial-distribution model and the Bateman equation to describe radionuclide decay. Quantitative analysis is conducted to examine the impact of various influencing factors on the total ß radioactivity. Specifically, the mass chains 89 and 137, as well as mass chains 95 and 144, which represent the radioactive surface and volume distributions are investigated respectively. The results show that the total ß radioactivity increases as the explosion yield increases and as the solidification temperature decreases, and increases slightly as the solidification time increases. The radioactivity will concentrate more on the larger size particles under harder geological conditions. The influencing factors have greater impacts on the radioactive volume distributions than on the surface distributions, and the variations in distinct mass chains under the same influencing factors are inconsistent. Overall, the solidification temperature and the geological condition have significant impacts on the distribution of particle radioactivity, followed by the effects of explosion yield and nuclear charge. The distribution of particle radioactivity is not significantly affected by the solidification time.

Clinical and forensic aspects of potassium iodide: Suddenly in high demand across Europe due to fears of radiation poisoning from a nuclear attack in Ukraine.

Potassium iodide has demonstrated several therapeutic applications over time, being the choice for shielding the thyroid during radiation emergencies involving radioiodine release. Amidst the ongoing military conflict between Ukraine and Russia and the growing concern regarding the potential deployment of nuclear weapons, there has been a surge in the demand for potassium iodide across Europe. This work aimed to comprehensively review the current knowledge regarding the pharmacology, physiology, adverse effects, the protective role in reducing the risk of thyroid cancer and recommendations for potassium iodide use during radiation emergencies. Evidence on adverse effects is scarce, as potassium iodide is generally well-tolerated. Guidelines for thyroid blocking with potassium iodide during radiation emergencies suggest that, among populations vulnerable to radioiodine exposure, the benefits of potassium iodide outweigh the risks of adverse effects. Controversial topics surrounding the utilization of potassium iodide in radiation emergencies include the prophylaxis in iodine-deficient regions and following the detonation of dirty bombs, whether granule formulations versus tablets should be used and mental health concerns. Although the rise in demand seems to be a justified security measure, it is essential to recognize that potassium iodide protects the thyroid from radioiodine and does not impact the body's absorption of other radioactive materials or defend against external radiation exposure.

Genetic Polymorphisms in Cardiovascular Disease: Effects Across Three Generations Exposed to Radiation from the Semipalatinsk Nuclear Test Site.

The population in the areas neighboring the Semipalatinsk Nuclear Test Site (SNTS) in the eastern region of Kazakhstan faces increased cardiovascular disease (CVD) risk. Previous research has not explored gene polymorphisms related to CVD in this population. Therefore, the present study examines the prevalence of six CVD-associated genotypes in three generations exposed to SNTS radiation. The genotyping of ApoE Leu28 → Pro, AGT Met174 → Thr, AGT Met235 → Thr, eNOS T786 → C, PON1 Gln192 → Arg, and EDN 1 Lys198 → Asn was performed using real-time polymerase chain reaction. The present study encompassed a cohort of 218 participants with a familial history of arterial hypertension and/or carotid artery disease spanning at least three generations. The analysis unveiled significant disparities in the prevalence of ApoE Leu28 → Pro, eNOS T786 → C, and PON1 Gln192 → Arg genotypes across different generations. Furthermore, a substantial variation in the distribution of the eNOS T786 → C genotype was observed between individuals of Kazakh and Russian ethnicities. Nevertheless, no significant discrepancies were detected in the frequencies of the investigated genotypes between genders. Further research in this area is warranted to enhance the understanding of the genetic factors contributing to CVD in the population exposed to radiation from the SNTS. Specifically, future studies should broaden the scope of genetic polymorphisms investigated and include representatives of healthy individuals who have not been exposed to radiation as controls.

Investigation of the distribution of transuranic radionuclides in marine sediment at the Montebello Islands, Western Australia.

Three nuclear weapons tests were conducted in the 1950s at the Montebello Islands, Western Australia. The detonations were of different yields and configurations (two tower tests, one ship test), and led to substantial radionuclide contamination within the surrounding terrestrial and marine ecosystems. The region possesses great ecological and recreational significance, particularly within the marine environment. However, studies conducted so far have largely neglected the marine ecosystem which makes up the majority of the Montebello Island Marine Park and in which most test fallout would have deposited. Here we investigated the distribution of the transuranic radionuclides 238Pu, 239,240Pu and 241Am in marine sediment from the Montebello Islands. Marine sediment samples near Operation Mosaic G2 and Operation Hurricane were collected and analysed by gamma and alpha spectrometry. Activity concentrations of 239,240Pu across both series ranged from 45 to 2900 Bq kg-1, while 241Am levels ranged from 2.8 to 70 Bq kg-1. Higher activity concentrations were observed in sediment near the land-based, higher yield Mosaic G2 test, compared with the ship-based, lower yield Hurricane test. Sediment samples located closer to the detonation site were also observed to have higher activity concentrations. Radioactive particles of 0.94 mm and 1.5 mm in diameter were identified by analysis of size-fractioned sediment via investigation of 152Eu levels, photostimulated autoradiography and point gamma spectroscopy. Particles were confirmed to have transuranic radionuclide interiors, with surface coatings which were dominated by vitrified CaCO3. Their long-term resistance to weathering and subsequent persistence in the marine environment can therefore be attributed to their coated structural form. Our study confirms the persistence of transuranic radionuclides in Montebello Island marine sediment and highlights the need for additional studies to improve our understanding of the nuclear legacy in this region.

Modeling Fallout from Nuclear Weapon Detonations: Efficient Activity and Dose Calculation of Radionuclides and Their Progeny.

ABSTRACT: The purpose of this paper is to present a practical method for quick determination of potential radiological doses and contaminations by fallout from nuclear detonations, or other releases, that includes the contributions from all nuclides. We precalculate individual (total) activities of all radionuclides from any initial cocktail and all their ingrowing progeny at a set of pinpoints in time with a logarithmic time-spacing. This is combined with the set of dose conversion factors (DCC) for any exposure pathway to obtain a time-dependent cocktail for the whole release as if it is one substance. An atmospheric dispersion model then provides the thinning coefficient of the released material to give local concentrations and dose rates. Progeny ingrowth is illustrated for pure 238 U and for a nuclear reactor that has been shut down. Efficient dose assessment is demonstrated for fallout from nuclear detonations and compared with the traditional approach of preselecting nuclides for specific endpoints and periods-of-interest. The compound cocktail DCC reduces the assessment of contaminations and potential dose-effects from fallout after a nuclear detonation to (the atmospheric dispersion of) only one tracer substance, representing any cocktail of nuclides and their progeny. This removes the need to follow all separate nuclides or an endpoint-specific preselection of "most important nuclides." As the cocktail DCCs can be precalculated and the atmospheric dispersion of only one tracer substance has to be modelled, our method is fast. The model for calculating cocktail DCCs is freely available, easily coupled to any regular atmospheric dispersion model, and therefore ready for operational use by others.

Bomb radiocarbon evidence for strong global carbon uptake and turnover in terrestrial vegetation.

Vegetation and soils are taking up approximately 30% of anthropogenic carbon dioxide emissions because of small imbalances in large gross carbon exchanges from productivity and turnover that are poorly constrained. We combined a new budget of radiocarbon produced by nuclear bomb testing in the 1960s with model simulations to evaluate carbon cycling in terrestrial vegetation. We found that most state-of-the-art vegetation models used in the Coupled Model Intercomparison Project underestimated the radiocarbon accumulation in vegetation biomass. Our findings, combined with constraints on vegetation carbon stocks and productivity trends, imply that net primary productivity is likely at least 80 petagrams of carbon per year presently, compared with the 43 to 76 petagrams per year predicted by current models. Storage of anthropogenic carbon in terrestrial vegetation is likely more short-lived and vulnerable than previously predicted.

Nuclear Imaginaries and Power in Oppenheimer.

Christopher Nolan's Oppenheimer is in awe of physics and the power it can bestow. Its central character is both mythic and human, and the film critiques and constructs the mythology surrounding him. The film presents science and technology as the individualized work of masculine genius, though it is ultimately more interested in nuclear weapons as political objects than as technological ones. Its nuclear imaginaries contain personal anxieties and stunning spectacle but also forget the nuclear uncanny and the human scale of nuclear weapons.

Consequence assessment of hypothetical urban radiological dispersal device incident in Korea.

Radiological Dispersal Devices (RDDs) are designed to disperse radioactive material over a wide area, leading to significant consequences to the environment and public health. This paper discusses the radiological effects of a potential RDD detonation containing 137Cs and 241Am in the commercial area of Busan, South Korea. The assessment, conducted with HotSpot Health Physics and RESRAD-RDD codes, found that summer had the most significant impact, with a maximum total effective dose equivalent (TEDE) of 280 mSv at 100 m and this decreased to 1 mSv at 4.5 km from the detonation point within the time interval of 35 min.

Neurocognitive Function in Aged Survivors Exposed to Atomic Bomb Radiation In Utero: The Radiation Effects Research Foundation Adult Health Study.

Although some adverse effects on neurocognitive function have been reported in children and adolescents irradiated prenatally during the atomic bombings and the Chernobyl nuclear accident, little information is available for effects on the elderly. Here we evaluate the effects of prenatal exposure to atomic bomb radiation on subjective neurocognitive function in aged survivors. To evaluate neurocognitive impairment, we mailed the Neurocognitive Questionnaire (NCQ), a self-administered scale, to prenatally exposed survivors, including clinic visitors and non-visitors at the time of the 2011 and 2013 Adult Health Study (AHS) examinations. We received replies from 444 individuals (mean age, 66.9 ± 0.6 years). After adjusting for sex, city, and educational background, we found no significant effects of radiation, clinic visit, or interaction between radiation and clinic visit on the scores of the 4 NCQ factors of metacognition, emotional regulation, motivation/organization, and processing speed. Even in analyses considering gestational age at the time of the bombings, none of the 4 NCQ factor scores was related to maternal uterine dose. There remains the limitation that this study consisted of healthy survivors, but we found no significant radiation effect on late-life cognition in people prenatally exposed to atomic bomb radiation.

Implications of "flash" radiotherapy for biodosimetry.

Extremely high dose rate radiation delivery (FLASH) for cancer treatment has been shown to produce less damage to normal tissues while having the same radiotoxic effect on tumor tissue (referred to as the FLASH effect). Research on the FLASH effect has two very pertinent implications for the field of biodosimetry: (1) FLASH is a good model to simulate delivery of prompt radiation from the initial moments after detonating a nuclear weapon and (2) the FLASH effect elucidates how dose rate impacts the biological mechanisms that underlie most types of biological biodosimetry. The impact of dose rate will likely differ for different types of biodosimetry, depending on the specific underlying mechanisms. The greatest impact of FLASH effects is likely to occur for assays based on biological responses to radiation damage, but the consequences of differential effects of dose rates on the accuracy of dose estimates has not been taken into account.