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1.
PLoS One ; 18(5): e0284482, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37200276

RESUMO

The global fallout from atmospheric nuclear weapons testing in the 1950s and 1960s caused by far the greatest exposure of mankind to ionizing radiation. Surprisingly few epidemiological studies of the possible health effects of atmospheric testing have been conducted. Here, long-term trends in infant mortality rates in the United States (U.S.) and five major European countries (EU5) were examined: The United Kingdom, Germany, France, Italy, and Spain. Bell-shaped deviations from a uniformly decreasing secular trend were found beginning in 1950, with maxima around 1965 in the U.S. and 1970 in EU5. From the difference between observed and predicted infant mortality rates, in the period 1950-2000, the overall increase in infant mortality rates was estimated to be 20.6 (90% CI: 18.6 to 22.9) percent in the U.S. and 14.2 (90% CI: 11.7 to 18.3) percent in EU5 which translates to 568,624 (90% CI: 522,359 to 619,705) excess infant deaths in the U.S. and 559,370 (90% CI: 469,308 to 694,589) in the combined five European countries. The results should be interpreted with caution because they rely on the assumption of a uniformly decreasing secular trend if there had been no nuclear tests, but this cannot be verified. It is concluded that atmospheric nuclear weapons testing may be responsible for the deaths of several million babies in the Northern Hemisphere.


Assuntos
Armas Nucleares , Cinza Radioativa , Lactente , Humanos , Estados Unidos , Cinza Radioativa/análise , Mortalidade Infantil , Europa (Continente)/epidemiologia , Alemanha
2.
Radiat Prot Dosimetry ; 199(8-9): 1012-1020, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37225232

RESUMO

Experiments simulating radioactive dirty bomb explosions in an urban area were performed at the National Institute of NBC Protection (SUJCHBO v.v.i.), Czech Republic. A solution containing 99mTc radionuclide was dispersed by an explosion on an open-air model of a square covered with filters. Subsequently, spectra of gamma rays originating in contaminated filters were measured by a hand-held NaI(Tl) spectrometer and laboratory HPGe spectrometers. The ambient dose equivalent rate at measuring vessels was set as well. Self-made standards had been prepared by dripping a defined amount of 99mTc solution uniformly on the filters to set the 99mTc surface contamination of measured samples. The urban area model's radioactive contamination map was set using previously determined filters' locations. The defined amount of 99mTc solution was dripped non-homogenously on some filters to estimate the impact of non-homogenous filters' coverage by radioactive aerosol' particles.


Assuntos
Armas Nucleares , Monitoramento de Radiação , Explosões , Academias e Institutos , República Tcheca
3.
J Environ Radioact ; 263: 107166, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37059048

RESUMO

Dirty bombs are considered one of the easiest forms of radiological terrorism, a form of terrorism based on the deliberate use of radiological material to cause adverse effects in a target population. One U.S. Government official has even described a dirty bomb attack as "all but inevitable". While people in the vicinity of the blast may experience acute radiation effects, people downwind may unknowingly be contaminated by the radioactive airborne particulate and face increased long-term cancer risk. The likelihood of increased cancer risk depends on the radionuclide used and its specific activity, its aerosolization potential, the particle sizes generated in the blast, and where a person is with respect to the detonation. Different studies have reported that plausible radionuclides for dirty bomb include 60Co, 90Sr, 137Cs, 192Ir, 241Am based on their availability in commercial sources as well as safeguards, the amount needed for adverse health effects, previous mishandling of radionuclides and malicious uses. In order to have increased long-term cancer risk, the radionuclide would have to deposit inside the body by entering the respiratory tract and then possibly migrate to other organs or bones (ground shine is not considered in this paper because areas affected by the event will likely become inaccessible). This implies that the particles will have to be smaller than 10 µm to be inhaled. Experiments involving the detonation of dirty bombs have shown that particles or droplets smaller than 10 µm are generated, independently from the initial radionuclide or its state (e.g., powder, solution). Atmospheric tests have shown that in unobstructed terrain, the radionuclide laden cloud can travel kilometers downwind even for relatively small amounts of explosives. Buildings in the path of the cloud can change the dose rate. For instance, in one experiment with a single building, the dose rate was 1-2 orders of magnitude lower behind the obstacle compared to its front face. For people walking around, the amount of particulate deposited on them and inhaled will depend on their path relative to the cloud, resulting in the counterintuitive result that the closer people may actually not be the ones more at risk because they could simply miss the bulk of the cloud in their wandering. In summary, the long-term cancer risk for people caught in a dirty bomb cloud away from the detonation requires considering where and when the people are, which radionuclide was used, and the layout of the obstacles (e.g., buildings, vegetation) in the path of the cloud.


Assuntos
Neoplasias , Armas Nucleares , Lesões por Radiação , Monitoramento de Radiação , Terrorismo , Humanos , Monitoramento de Radiação/métodos , Neoplasias/complicações
4.
Chemosphere ; 329: 138674, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37054845

RESUMO

Starting from 1952 C.E. more than 540 atmospheric nuclear weapons tests (NWT) were conducted in different locations of the Earth. This lead to the injection of about 2.8 t of 239Pu in the environment, roughly corresponding to a total 239Pu radioactivity of 6.5 PBq. A semiquantitative ICP-MS method was used to measure this isotope in an ice core drilled in Dome C (East Antarctica). The age scale for the ice core studied in this work was built by searching for well-known volcanic signatures and synchronising these sulfate spikes with established ice core chronologies. The reconstructed plutonium deposition history was compared with previously published NWT records, pointing out an overall agreement. The geographical location of the tests was found to be an important parameter strongly affecting the concentration of 239Pu on the Antarctic ice sheet. Despite the low yield of the tests conducted in the 1970s, we highlight their important role in the deposition of radioactivity in Antarctica due to the relative closeness of the testing sites.


Assuntos
Armas Nucleares , Plutônio , Cinza Radioativa , Cinza Radioativa/análise , Regiões Antárticas , Plutônio/análise , Camada de Gelo
6.
Cancer Rep (Hoboken) ; 6(2): e1697, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36806720

RESUMO

BACKGROUND: A mathematical model of the radiation-induced cancer was devised to explain the change of incidence rates pursued by Radiation Effect Research Foundation for 25 years. AIM: The aim of this work is construction of mechanisms of radiation-induced cancer and cancers observed in the daily life. METHODS AND RESULTS: First, we found a way to separate spontaneous cancers from radiation-induced cancers observed among atomic-bomb victims in Hiroshima and Nagasaki districts by using a constructed algorithm. The isolated incidence rates of radiation-induced cancers were reproduced by a two-stage model mechanical collision of impinging radiation with cells and succeeding mutation of the damaged cell to cancer. This model satisfactorily reproduced observed solid cancer incidence rates. We further attempted to construct a mathematical model for the age-dependence of spontaneous cancers appearing in the daily life and concluded that the cancer should be generated at cell division. CONCLUSION: With these findings, we reached to a conclusion that cancers may be suppressed by eliminating damaged cells with mild-dose radiation.


Assuntos
Neoplasias Induzidas por Radiação , Guerra Nuclear , Armas Nucleares , Humanos , Neoplasias Induzidas por Radiação/epidemiologia , Neoplasias Induzidas por Radiação/etiologia , Incidência , Modelos Teóricos
7.
Artigo em Inglês | MEDLINE | ID: mdl-36232066

RESUMO

The current geopolitical situation and the war on Ukraine's territory generate questions about the possible use of a nuclear weapon and create the need to refresh emergency protective plans for the population. Ensuring the protection of public health is a national responsibility, but the problem is of international size and global scale. Radiological or nuclear disasters need suitable decision making at the right time, which determine large effective radiation protection activities to ensure public health is protected, reduce fatalities, radiation disease, and other effects. In this study, a simulation of a single nuclear weapon detonation with an explosion yield of 0.3 and 1 Mt was applied for a hypothetical location, to indicate the required decision making and the need to trigger protocols for the protection of the population. The simulated explosion was located in a city center, in a European country, for the estimation of the size of the effects of the explosion and its consequences for public health. Based on the simulation results and knowledge obtained from historical nuclear events, practical suggestions, discussion, a review of the recommendations was conducted, exacerbated by the time constraints of a public health emergency. Making science-based decisions should encompass clear procedures with specific activities triggered immediately based on confirmed information, acquired from active or/and passive warning systems and radiometric specific analysis provided by authorized laboratories. This study has the potential to support the preparedness of decision makers in the event of a disaster or crisis-related emergency for population health management and summarizes the strengths and weaknesses of the current ability to respond.


Assuntos
Planejamento em Desastres , Armas Nucleares , Proteção Radiológica , Liberação Nociva de Radioativos , Tomada de Decisões , Planejamento em Desastres/métodos , Saúde Pública , Proteção Radiológica/métodos , Liberação Nociva de Radioativos/prevenção & controle
8.
Radiat Prot Dosimetry ; 198(13-15): 896-903, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36083730

RESUMO

Environmental tritium are natural and anthropogenic origins, the distribution has spread in atmosphere, hydrosphere and biosphere as a variety of chemical forms. The natural tritium is produced by nuclear reactions of neutron with N and O in the upper atmosphere, the production rate changes with 11-year cycle of the solar activity. The production and radioactive decay of natural tritium is balanced on the whole earth, results in the inventory of about 1 EBq. Anthropogenic tritium by nuclear weapons testing had been released in 1950s-1960s, at highest intensity just before the Partial Test Ban Treaty in 1963, and the total release would be 186 EBq. In accordance with a peaceful use of nuclear energy, tritium has been releasing to the environment as airborne and liquid effluents from nuclear power plants and nuclear fuel reprocessing plants. The release from the nuclear power plants depends on the reactor type. Other sources are the tritium production facility of military purpose and the consumer products that use tritium as luminescent energy and disposed to landfill site. Internal dose is only concerned on tritium due to low decay energy, suggesting tritium concentrations in drinking water and food are critical for dose evaluation.


Assuntos
Poluentes Radioativos do Ar , Armas Nucleares , Poluentes Radioativos do Ar/análise , Atmosfera , Centrais Nucleares , Trítio/análise
9.
10.
Health Phys ; 123(4): 267-277, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36049133

RESUMO

ABSTRACT: The exposure rate distribution was quantified over a site of three activated potassium bromide radiological dispersal device detonations at the Idaho National Laboratory Radiological Response Training Range with unmanned aerial vehicle (UAV) and ground-based methods. Discussions on the methods' survey characteristics, such as survey time, data spatial resolution, and area coverage, serve to inform those concerned with radiological response and cleanup efforts. Raster scans over the site at 4 m s-1 with 6 m between passes at an altitude of 4 m above ground level were executed with a 2.54 cm × 2.54 cm × 7.62 cm cesium iodide, sodium-doped [CsI(Na)] sensor mounted to a UAV. Exposure rates were calculated from the spectra obtained by the CsI(Na) using a flux unfolding method. Data obtained from the UAV raster were interpolated to produce a continuous exposure rate map across the site. The activity on the ground, inferred from collimated, ground-based sensor (Nomad) measurements in previous work, was used to calculate exposure rate distributions at the same altitude as the UAV-mounted CsI(Na) sensor. Agreement between Nomad and UAV exposure rate distributions is observed at rates up to 1.0 mR h-1 after corrections for ground effects were implemented on the Nomad data. Discrepancies in exposure rate contours are present at higher rates, directly above the detonation locations. In areas of high exposure rate gradients, it is anticipated that a faster UAV-mounted sensor and more refined scans by the UAV will improve characterization of the distribution.


Assuntos
Armas Nucleares , Tecnologia de Sensoriamento Remoto , Brometos , Idaho , Compostos de Potássio , Radiografia
11.
Sci Rep ; 12(1): 16209, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36171442

RESUMO

Many studies on ionizing radiation (IR) exposure during childhood have shown deleterious effects on the central nervous system (CNS), however results regarding adult exposure are inconsistent, and no systematic reviews have been performed. The objectives are to synthesize the findings and draw evidence-based conclusions from epidemiological studies on the risk of benign and malignant brain and CNS tumors in humans exposed to low-to-moderate doses (< 0.5 Gy) of IR during adulthood/young adulthood. A systematic literature search of four electronic databases, supplemented by a hand search, was performed to retrieve relevant epidemiological studies published from 2000 to 2022. Pooled excess relative risk (ERRpooled) was estimated using a random effect model. Eighteen publications were included in the systematic review and twelve out of them were included in a meta-analysis. The following IR sources were considered: atomic bombs, occupational, and environmental exposures. No significant dose-risk association was found for brain/CNS tumors (ERRpooled at 100 mGy = - 0.01; 95% CI: - 0.05, 0.04). Our systematic review and meta-analysis did not show any association between exposure to low-to-moderate doses of IR and risk of CNS tumors. Further studies with histological information and precise dose assessment are needed.


Assuntos
Neoplasias do Sistema Nervoso Central , Armas Nucleares , Exposição Ocupacional , Exposição à Radiação , Adulto , Neoplasias do Sistema Nervoso Central/epidemiologia , Neoplasias do Sistema Nervoso Central/etiologia , Exposição Ambiental , Humanos , Exposição Ocupacional/efeitos adversos , Exposição à Radiação/efeitos adversos , Radiação Ionizante , Adulto Jovem
12.
J Radiat Res ; 63(Supplement_1): i45-i53, 2022 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-35968990

RESUMO

There are two types of exposure to atomic bomb (A-bomb) radiation: exposure to initial radiation released at the time of the detonation of the bomb, and exposure to residual radiation, which remains afterwards. Health hazards caused by exposure from residual radiation have not yet been clarified. The purpose of our study was to reveal the relationships between mortality risk from solid cancer and residual radiation based on data from the early entrants to Hiroshima. It is hard to identify the individual residual radiation doses. However, these are assumed to depend on the date of entry and the entrants' behavior. Individual behavior is thought to be closely related to gender and age at exposure. We investigated a cohort of 45 809 individuals who were living in Hiroshima Prefecture on 1 January 1970 and were registered on the Database of Atomic Bomb Survivors as entrants after the bombing. Poisson regression methods were used to estimate excess relative risks (ERR) with data cross-classified by sex, age at entry, and date of entry. In males in their 20s, 30s, and 40s at entry and in females less than 10 years old and in their 40s at entry, solid cancer mortality risks were significantly higher among persons who entered the city on the day of the bombing than those who entered three or more days later. With adjustments for the age-dependent sensitivities to radiation exposure, it was extrapolated that middle-aged people who entered the city on the day of the bombing were exposed to higher levels of residual radiation than younger people.


Assuntos
Neoplasias , Guerra Nuclear , Armas Nucleares , Criança , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Risco
13.
Med Confl Surviv ; 38(3): 184-202, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35836374

RESUMO

This article attempts to put the Ukrainian conflict in the wider context of nuclear weapons possession and potential use, to point out how its conduct should affect public perception of such use, and the urgency for effective nuclear arms control measures including a determined resolve to implement the United Nations' 2017 Treaty on the Prevention of Nuclear Weapons.


Assuntos
Armas Nucleares , Humanos , Cooperação Internacional , Ucrânia , Nações Unidas
15.
Ber Wiss ; 45(1-2): 219-244, 2022 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-35655358
16.
Eur J Epidemiol ; 37(3): 221-225, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35426580

RESUMO

Recent incidents at nuclear facilities in Ukraine related to the attacks from Russian forces highlight the fragility of nuclear power plants and other nuclear facilities in war and the very real potential for another environmental nuclear disaster and associated health risks in Europe. Nuclear catastrophes from war can occur from radioactive materials released from war threatened nuclear power plants and other nuclear facilities in war zones, in addition to the direct threat from the deployment of nuclear weaponry and can result in immediate and long-term health impacts. Despite historical nuclear catastrophic events, including the Chernobyl nuclear power plant accident and atomic bombings of Hiroshima and Nagasaki, and that for more than a century epidemiologists have studied the consequences of radiation exposures, there are still major unanswered questions regarding radiation risks and human health. Epidemiologists will need to continue to quantify the health effects from exposure to environmental radiation, including background radiation, and are able to contribute to conversations about reliance on nuclear energy and alternative energy futures. As a society we are compelled to rethink our ties to nuclear energy, especially with the potential of increasing reliance on nuclear power amid oil and gas crisis and considering climate change, nuclear warfare, including nuclear weapon testing, and the fragility of humanity and health to even low doses of radiation from these and other natural and unnatural sources.


Assuntos
Acidente Nuclear de Chernobyl , Desastres , Armas Nucleares , Europa (Continente) , Humanos , Reatores Nucleares
17.
Health Phys ; 122(5): 632-644, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35383637

RESUMO

ABSTRACT: Healthcare facilities around the world routinely use radioactive sources to diagnose and treat illness. To effectively manage the security of radioactive sources, these facilities need to understand the risk, which is comprised of threat, vulnerability, and consequences. The threat component of risk requires knowledge of potential adversaries and understanding their capabilities and intentions. To help articulate the multiple layers of threat and support better informed decisions, the research developed a risk-based methodology to evaluate radiological security at the facility level. The methodology is applied to a radiological dispersal device (RDD) incident from three radionuclides of concern: 137Cs, 60Co, and 192Ir. The results of the research have led to the creation of a potential facility risk index (PFRI). The PFRI is mathematically represented as the exponential product of the maximum expected utility among the threat groups, the sum of geographic vulnerability and cultural vulnerability, and net consequences. The PFRI is a novel risk index that quantifies the facility risk on a scale of 1 to 10, 1 being "very low risk" and 10 being "very high risk." A MATLAB-based graphical user interface (GUI) tool was also developed to enable the radiological facility (i.e., healthcare facility) staff to conduct self-assessments and manage their most valuable assets. The PFRI methodology is a useful starting point for any healthcare facility risk assessment and is a valuable input for decision makers considering potential investments in security upgrades.


Assuntos
Radioisótopos de Césio , Armas Nucleares , Humanos , Radioisótopos de Irídio
19.
Appl Radiat Isot ; 184: 110156, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35301173

RESUMO

Operated by the Comprehensive Nuclear-Test-Ban Treaty Organisation, the International Monitoring System is used by almost 200 nations to monitor for nuclear weapons tests. The IMS is still under development, and the Comprehensive Nuclear-Test-Ban Treaty has not yet entered into force, however the radionuclide component has proved instrumental in radically changing both nuclear verification science and researchers' understanding of the dynamic global radiation background. After more than 20 years, the network is mostly complete, however the technology utilised for the particulate monitoring component remains practically the same, despite a number of laboratories developing coincidence systems that can offer orders of magnitude improvements in detection sensitivity and reliability. This paper describes the status of the technology, and the advantages of implementing this within the International Monitoring System. Furthermore, the performance of a prototype system developed by the Comprehensive Nuclear-Test-Ban Treaty Organisation is presented, and the implications of introducing this technology considered.


Assuntos
Poluentes Radioativos do Ar , Armas Nucleares , Monitoramento de Radiação , Poluentes Radioativos do Ar/análise , Poeira , Monitoramento de Radiação/métodos , Radioisótopos/análise , Reprodutibilidade dos Testes , Radioisótopos de Xenônio/análise
20.
Radiat Res ; 197(5): 491-508, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35213725

RESUMO

Recent analysis of all solid cancer incidence (1958-2009) in the Life Span Study (LSS) revealed evidence of upward curvature in the radiation dose response among males but not females. Upward curvature in sex-averaged excess relative risk (ERR) for all solid cancer mortality (1950-2003) was also observed in the 0-2 Gy dose range. As reasons for non-linearity in the LSS are not completely understood, we conducted dose-response analyses for all solid cancer mortality and incidence applying similar methods [1958-2009 follow-up, DS02R1 doses, including subjects not-in-city (NIC) at the time of the bombing] and statistical models. Incident cancers were ascertained from Hiroshima and Nagasaki cancer registries, while cause of death was ascertained from death certificates throughout Japan. The study included 105,444 LSS subjects who were alive and not known to have cancer before January 1, 1958 (80,205 with dose estimates and 25,239 NIC subjects). Between 1958 and 2009, there were 3.1 million person-years (PY) and 22,538 solid cancers for incidence analysis and 3.8 million PY and 15,419 solid cancer deaths for mortality analysis. We fitted sex-specific ERR models adjusted for smoking to both types of data. Over the entire range of doses, solid cancer mortality dose-response exhibited a borderline significant upward curvature among males (P = 0.062) and significant upward curvature among females (P = 0.010); for solid cancer incidence, as before, we found a significant upward curvature among males (P = 0.001) but not among females (P = 0.624). The sex difference in magnitude of dose-response curvature was statistically significant for cancer incidence (P = 0.017) but not for cancer mortality (P = 0.781). The results of analyses in the 0-2 Gy range and restricted lower dose ranges generally supported inferences made about the sex-specific dose-response shape over the entire range of doses for each outcome. Patterns of sex-specific curvature by calendar period (1958-1987 vs. 1988-2009) and age at exposure (0-19 vs. 20-83) varied between mortality and incidence data, particularly among females, although for each outcome there was an indication of curvature among 0-19-year-old male survivors in both calendar periods and among 0-19-year-old female survivors in the recent period. Collectively, our findings indicate that the upward curvature in all solid cancer dose response in the LSS is neither specific to males nor to incidence data; its evidence appears to depend on the composition of sites comprising all solid cancer group and age at exposure or time. Further follow up and site-specific analyses of cancer mortality and incidence will be important to confirm the emerging trend in dose-response curvature among young survivors and unveil the contributing factors and sites.


Assuntos
Neoplasias Induzidas por Radiação , Guerra Nuclear , Armas Nucleares , Adolescente , Adulto , Sobreviventes de Bombas Atômicas , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Japão/epidemiologia , Longevidade , Masculino , Neoplasias Induzidas por Radiação/etiologia , Adulto Jovem
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