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1.
J Environ Radioact ; 255: 107030, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36191507

RESUMO

137Cs and 241Pu (via 241Am) concentrations were measured γ-spectrometrically on air filters from the early 1960s (mainly from 1964-66) from Vienna, Austria, and an alpine station in Salzburg, Austria. Accelerator mass spectrometry (AMS) was used to determine 240Pu/239Pu, 236U/238U and 233U/236U atom ratios as well as 236U, 239Pu and 240Pu atom concentrations. The maximum 236U/238U atom ratio of these unique undisturbed global fallout samples was (1.19 ± 0.31) × 10-5 in spring 1964. The 233U/236U atom ratios were found within (0.15-0.49) × 10-2 and indicate that the weapons tests of the early 1960s can be excluded as 233U source. The 236U/239Pu atom ratios were calculated in the range of 0.22-0.48.


Assuntos
Filtros de Ar , Plutônio , Monitoramento de Radiação , Cinza Radioativa , Urânio , Monitoramento de Radiação/métodos , Áustria , Estudos Retrospectivos , Plutônio/análise , Cinza Radioativa/análise , Urânio/análise
2.
Environ Sci Pollut Res Int ; 29(57): 85777-85788, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35595889

RESUMO

The Aare river system in Switzerland, with two nuclear power plants on the banks of the river, and its intermediate lakes and reservoirs, provides a unique opportunity to analyze the contribution of different sources to the radioactive contamination. Sediment cores were collected from two lakes and a reservoir, all connected by the river Aare. In order to study the influence of the Chernobyl accident, one sediment core was collected from a lake in the southern part of Switzerland. The sediment cores were sliced and analyzed with gamma ray spectrometry. Plutonium, americium, and uranium were extracted radiochemically, and their concentrations were measured with a sector field ICP-MS. The uranium isotope ratios were further measured with a multi collector ICP-MS. The maximum 137Cs activity from the Chernobyl accident and the Pu and 137Cs activities associated to the 1963 global fallout maximum were well identified in sediments from all three lakes. High-resolution records of plutonium isotopes in the zone of the sediments corresponding to the period of maximum fallout from the atmospheric nuclear weapon testing showed distinct fingerprints, depending on the different test activities. Pu isotope ratios could be used to detect non-global fallout plutonium. The ratio 241Am/241Pu was used to determine the age of the plutonium. Despite of very low 241Pu and 241Am concentrations, the calculated plutonium production dates seemed to be reasonable for the sediment layers corresponding to the NWT tests. The calculated production date of the plutonium in the upper most 15 cm of the sediment core seemed to be younger. The reason for this could be additional non-global fallout plutonium. For the lake sediments, natural ratios for 235U/238U and enriched or depleted ratios for 234U/238U were measured, depending on the lake. A small increase of the 236U/238U ratio could be recognized for the NWT zone in all three lakes and, for Lake Lugano, a further distinct increase in the Chernobyl layer.


Assuntos
Plutônio , Cinza Radioativa , Urânio , Poluentes Radioativos da Água , Plutônio/análise , Amerício/análise , Lagos , Urânio/análise , Poluentes Radioativos da Água/análise , Suíça , Sedimentos Geológicos/química , Radioisótopos de Césio/análise , Isótopos/análise , Cinza Radioativa/análise
3.
Sci Total Environ ; 806(Pt 1): 150482, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34844331

RESUMO

This work reports the first high-resolution deposition records of anthropogenic uranium (236U and 233U) in a sediment core taken at the continental slope of the Philippine Sea off Mindanao Island in the equatorial northwest Pacific Ocean. Two notable peaks were observed in both profiles of 236U and 233U concentrations, with a narrower peak in 1951-1957 corresponding to close-in Pacific Proving Grounds (PPG) signal, and a broader peak in 1960s-1980s corresponding to the global fallout from nuclear weapons testing. 236U and 233U areal cumulative inventories in the studied sediment core are (2.79 ± 0.20) ∙ 1012 atom ∙ m-2 and (3.12 ± 0.41) ∙ 1010 atom ∙ m-2, respectively, about 20-30% of reported 233U and 236U inventories from the direct global fallout deposition. The overall 233U/236U atomic ratios obtained in this work vary within (0.3-3.5) âˆ™ 10-2, with an integrated 233U/236U atomic ratio of (1.12 ± 0.17) âˆ™ 10-2. The contribution from global fallout and close-in PPG fallout to 236U in the sediment core is estimated to be about 69% and 31%, respectively. We believe the main driving process for anthropogenic uranium deposition in the Philippine sediment is continuous scavenging of dissolved 236U from the surface seawater by sinking particles.


Assuntos
Plutônio , Monitoramento de Radiação , Cinza Radioativa , Urânio , Poluentes Radioativos da Água , Oceano Pacífico , Filipinas , Plutônio/análise , Cinza Radioativa/análise , Poluentes Radioativos da Água/análise
4.
Cancer Invest ; 39(10): 902-907, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34486897

RESUMO

The Japanese Lifespan Study (LSS) of the A-Bomb survivors is the principal basis of the current legal radiological framework. Evidence provided for the first time here shows that internal exposure to radiologically significant quantities of Uranium-234 contained in sub-micron particle rainout from the un-fissioned weapon warhead, the Black Rain, is a missing exposure in the LSS analysis. It is argued that this is responsible for a background excess cancer risk in all the LSS dose groups. This, together with epidemiological evidence based on unexposed controls falsifies the LSS cancer vs. dose regression coefficients for internal exposure.


Assuntos
Sobreviventes de Bombas Atômicas , Longevidade , Neoplasias Induzidas por Radiação/mortalidade , Guerra Nuclear , Exposição à Radiação/efeitos adversos , Cinza Radioativa/efeitos adversos , Chuva/química , Humanos , Japão , Urânio
5.
Nat Commun ; 12(1): 823, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33547296

RESUMO

We present an application of multi-isotopic fingerprints (i.e., 236U/238U, 233U/236U, 236U/129I and 129I/127I) for the discovery of previously unrecognized sources of anthropogenic radioactivity. Our data indicate a source of reactor 236U in the Baltic Sea in addition to inputs from the two European reprocessing plants and global fallout. This additional reactor 236U may come from unreported discharges from Swedish nuclear research facilities as supported by high 236U levels in sediment nearby Studsvik, or from accidental leakages of spent nuclear fuel disposed on the Baltic seafloor, either reported or unreported. Such leakages would indicate problems with the radiological safety of seafloor disposal, and may be accompanied by releases of other radionuclides. The results demonstrate the high sensitivity of multi-isotopic tracer systems, especially the 233U/236U signature, to distinguish environmental emissions of unrevealed radioactive releases for nuclear safeguards, emergency preparedness and environmental tracer studies.


Assuntos
Radioisótopos/análise , Água do Mar/análise , Urânio/análise , Poluentes Radioativos da Água/análise , Países Bálticos , Humanos , Cinza Radioativa/análise , Suécia
6.
Health Phys ; 119(4): 504-516, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32881735

RESUMO

The Trinity test device contained about 6 kg of plutonium as its fission source, resulting in a fission yield of 21 kT. However, only about 15% of the Pu actually underwent fission. The remaining unfissioned plutonium eventually was vaporized in the fireball and after cooling, was deposited downwind from the test site along with the various fission and activation products produced in the explosion. Using data from radiochemical analyses of soil samples collected postshot (most many years later), supplemented by model estimates of plutonium deposition density estimated from reported exposure rates at 12 h postshot, we have estimated the total activity and geographical distribution of the deposition density of this unfissioned plutonium in New Mexico. A majority (about 80%) of the unfissioned plutonium was deposited within the state of New Mexico, most in a relatively small area about 30-100 km downwind (the Chupadera Mesa area). For most of the state, the deposition density was a small fraction of the subsequent deposition density of Pu from Nevada Test Site tests (1951-1958) and later from global fallout from the large US and Russian thermonuclear tests (1952-1962). The fraction of the total unfissioned Pu that was deposited in New Mexico from Trinity was greater than the fraction of fission products deposited. Due to plutonium being highly refractory, a greater fraction of the Pu was incorporated into large particles that fell out closer to the test site as opposed to more volatile fission products (such as Cs and I) that tend to deposit on the surface of smaller particles that travel farther before depositing. The plutonium deposited as a result of the Trinity test was unlikely to have resulted in significant health risks to the downwind population.


Assuntos
Poluentes Radioativos do Ar/análise , Exposição por Inalação/análise , Fissão Nuclear , Plutônio/análise , Cinza Radioativa/análise , Medição de Risco/métodos , Poluentes Radioativos do Solo/análise , Radioisótopos de Césio/análise , Humanos , Radioisótopos do Iodo/análise , Armas Nucleares/estatística & dados numéricos , Doses de Radiação , Monitoramento de Radiação
7.
Chemosphere ; 239: 124783, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31726517

RESUMO

This research concerned radioactivity of lichens and mosses from coastal zones of the Canadian Arctic and Alaska. Over 50 samples were collected from 7 positions during two scientific expeditions in 2012 and 2013. The tundra contamination caused by anthropogenic radionuclides was relatively low, reaching mean values with SD's of: 17.4 ±â€¯3.5 Bq/kg for 90Sr, 14.0 ±â€¯2.9 Bq/kg for 134Cs, 38.4 ±â€¯7.5 Bq/kg for 137Cs, 0.86 ±â€¯0.24 Bq/kg for 239+240Pu, 0.065 ±â€¯0.017 Bq/kg for 238Pu and 0.50 ±â€¯0.13 Bq/kg for 241Am. The increase of activity concentration with increasing latitudes was noticed mostly in regard to 90Sr, Pu isotopes and 241Am. The analysis of isotopic ratios exhibited dominant contribution of the global fallout (+SNAP 9A satellite re-entry fallout) for the presence of plutonium isotopes and 241Am. The Fukushima fallout signature was identified in a few lichens from Alaska. However, the influence of additional unknown factor on the occurrence of 90Sr and 137Cs has been detected in western part of Canadian Arctic. Natural radioisotopes of thorium and uranium were found throughout the entire investigated region and the average values of activity concentration with SD's were as follows: 2.92 ±â€¯0.47 Bq/kg for 230Th, 2.61 ±â€¯0.48 Bq/kg for 232Th, 4.32 ±â€¯0.80 Bq/kg for 234U and 3.97 ±â€¯0.71 Bq/kg for 238U. Examined Western Arctic tundra was not affected with any technically enhanced natural radioactivity.


Assuntos
Poluentes Radioativos do Ar/análise , Briófitas/química , Líquens/química , Cinza Radioativa/análise , Poluentes Radioativos do Solo/análise , Poluentes Radioativos da Água/análise , Alaska , Regiões Árticas , Canadá , Radioisótopos de Césio/análise , Acidente Nuclear de Fukushima , Plutônio/análise , Monitoramento de Radiação/métodos , Tório/análise , Urânio/análise
8.
Probl Radiac Med Radiobiol ; 24: 439-448, 2019 Dec.
Artigo em Inglês, Ucraniano | MEDLINE | ID: mdl-31841485

RESUMO

OBJECTIVE: to identify the psycho-emotional state of children - residents of radioactively contaminated territories and children displaced from the zone of armed conflict in the south-east of Ukraine, and evaluate the effectiveness of art therapy application to correct its disturbances. MATERIALS AND METHODS: The psycho-emotional state was determined in 113 children, of which 57 children from radioactively contaminated territories with 137Cs content in the body from 269 Bq to 7024 Bq (group I) and 56 chil- dren displaced from the zone of military conflict in the Southeast of Ukraine (group II). The age of children ranged from 10 to 17 years. The children were hospitalized to the childrens' clinics of the NRCRM because of functional dis- orders and chronic somatic pathology. The psycho-emotional state of children was evaluated using the «non-exis- tent animal¼ test. It was analyzed for three symptoms - anxiety, aggressiveness and neuropsychiatric exhaustion and was evaluated by scoring points. Correction of the psychoemotional condition was carried out by the method of art therapy in the form of a serial drawing. Psychological testing was performed twice: at admission to the hospital and after the end of the art therapy. RESULTS: The results of the primary examination of the psycho-emotional state of children by the «non-existent ani- mal¼ test showed that in children - residents of radioactively contaminated territories the state of anxiety was reg- istered in all 57 children (100 %), the state of aggression - in 38 children (66.7%); exhaustion - in 37 children (64.9 %). In children who have been displaced from the zone of armed conflict in the south-east of Ukraine, the state of anxiety was also registered in all 56 children (100 %), the status of aggression was determined in 53 chil- dren (94.6 %), and the state of exhaustion - in 44 children (78.6 %). It was established that in children displaced from the combat zone in the Southeast of Ukraine, the quantitative indices of anxiety and aggression states were sig- nificantly higher than in children living in radioactively contaminated territories (p < 0.001), whereas nor by frequen- cy, nor by the degree of severity of exhaustion state they did not clearly differ (p > 0.05). Correlation analysis with the definition of Spearman's criterion did not reveal likely association between the content of 137Cs in the body of children - residents of radioactively contaminated territories and the peculiarities of their psycho-emotional state. CONCLUSIONS: The use of the art therapy method in the form of a serial drawing for children - residents of radioac- tively contaminated territories and children moved from the combat zone in the south-east of Ukraine, led to a sig- nificant positive effect, which was characterized by a decrease in the manifestations of symptoms of anxiety and aggressiveness. The state of exhaustion was less well corrected and its indices only had a tendency to improve. Thus, the method of art therapy in the form of a serial drawing is characterized by efficiency, simplicity of execution, low cost, it can be widely used in children's teams to correct disorders of the psycho-emotional state.


Assuntos
Ansiedade/terapia , Conflitos Armados/psicologia , Arteterapia/métodos , Acidente Nuclear de Chernobyl , Fadiga/terapia , Adolescente , Agressão/psicologia , Ansiedade/etiologia , Ansiedade/fisiopatologia , Ansiedade/psicologia , Radioisótopos de Césio/análise , Criança , Fadiga/etiologia , Fadiga/fisiopatologia , Fadiga/psicologia , Feminino , Migração Humana , Humanos , Masculino , Exposição à Radiação/efeitos adversos , Cinza Radioativa/efeitos adversos , Radiometria , Ucrânia
10.
Health Phys ; 117(2): 118-132, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31225827

RESUMO

Dedication: The research of the US Transuranium and Uranium Registries relies heavily upon postmortem autopsy findings and radiochemical analysis of tissues. The enormous debt owed to those now-deceased registrants who unselfishly voluntarily participated in the US Transuranium and Uranium Registries program through postmortem donation of their tissues and to those still-living registrants who have volunteered to be future postmortem tissue donors is hereby acknowledged with gratitude. The scientific findings derived from postmortem analysis of these tissues have been instrumental in advancing our understanding of the actinide elements in humans and have led to refinement, validation, and confidence in safety standards for those who work with these elements as well as for the general public. To these generous and anonymous persons who made this ultimate contribution, this paper is dedicated with great thanks and admiration.


Assuntos
Exposição Ocupacional/análise , Proteção Radiológica/estatística & dados numéricos , Cinza Radioativa/análise , Sistema de Registros/estatística & dados numéricos , Doadores de Tecidos , Urânio/análise , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Plutônio/análise , Doses de Radiação , Adulto Jovem
11.
J Environ Radioact ; 205-206: 17-23, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31082674

RESUMO

Anthropogenic radionuclides, like 236U and 239,240Pu, are present in the environment as a result of global fallout from nuclear weapons tests conducted in the 1950s and 1960s and can potentially be used as tracers in soil erosion and sediment movement studies. Here, we report data on 236U and 239,240Pu in soil samples from the Motueka Valley (New Zealand) and for the first time from two remote islands Rarotonga and Atiu (Cook Islands) in the South Pacific. 236U and 239,240Pu were measured using Accelerator Mass Spectrometry (AMS) at the Australian National University. The 236U and 239Pu isotope concentrations versus soil depth and the 240Pu/239Pu and 236U/239Pu isotope ratios are discussed for each site. The radionuclide depth dependence revealed any soil disturbance, whereas the isotopic signatures indicated the source of the radionuclides' origin.


Assuntos
Plutônio/análise , Monitoramento de Radiação , Cinza Radioativa/análise , Poluentes Radioativos do Solo/análise , Urânio/análise , Espectrometria de Massas , Nova Zelândia , Polinésia
12.
J Environ Radioact ; 197: 1-8, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30463028

RESUMO

More nuclear power plants continue to be built in China. Due to its long half-life, radiotoxicity and potential application as an environmental tracer, 236U is one of the most important artificial radionuclides deserving more study since activity data are important for risk assessment. However, the ultra-trace activity of 236U and its dilution by natural uranium isotopes make it difficult to distinguish its sources and there are only limited global fallout 236U data for present in Chinese environmental samples. In order to understand the background levels for uranium isotopes, especially 236U, and clarify their sources, inductively coupled plasma tandem mass spectrometry (ICP-MS/MS) was applied to analyze uranium isotopes in 48 soil samples from Hunan Province, China. The 234U, 235U, 238U and 236U concentrations were measured as 9.91-33.7, 0.312-1.43, 6.63-28.7 Bq kg-1 and (1.61-21.3) × 107 atoms g-1, while, the 236U/238U, 234U/238U and 235U/238U atom ratios were (0.470-4.91) × 10-8, (5.10-9.31) × 10-5, and (7.11-7.82) × 10-3, respectively. The uranium isotopic fractionation may be due to irrigation of the agricultural lands where the samples were collected. Considering the facts that neither previous nuclear tests nor nuclear accidents had occurred in Hunan Province and the present 236U/238U atom ratios were included in the range of global fallout values in other areas, it may be concluded that 236U in soils from Hunan Province is mainly from global fallout. To the best of the authors' knowledge, the presence of global fallout 236U in soil samples from China has been confirmed for the first time, and these values may be useful as background data for risk assessment in the future.


Assuntos
Monitoramento de Radiação , Cinza Radioativa/análise , Poluentes Radioativos do Solo/análise , Urânio/análise , China , Centrais Nucleares , Liberação Nociva de Radioativos , Solo/química
13.
J Environ Radioact ; 192: 478-484, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30096706

RESUMO

236U, 239Pu and 240Pu are present in soils mainly as a result of the local- and global-fallout from the atmospheric nuclear weapons tests carried out mainly in the 1950's and 1960's. In this work we provide new data on the presence of 236U and 239,240Pu in surface soils (i.e. up to 5 cm depth) from Chile and Africa. The results were obtained by low-energy Accelerator Mass Spectrometry (AMS). In the case of the Chilean samples, 236U/239Pu atom ratios show a high variability and are in general higher than the reported value for the global fallout in the Northern Hemisphere, ranging from 0.2 to 1.5. The 236U atomic concentrations range from 3.5 × 106 to 9.1 × 106 atoms/g, and are at least two orders of magnitude lower than the reported values in the Northern Hemisphere. The measured 240Pu/239Pu atom ratio in soils from South-Africa and Mozambique are of about 0.17, in agreement with the expected one for global-fallout at those coordinates. To best knowledge of the authors the present work is the first publication on 236U concentrations and 236U/239Pu atom ratios in soils from South-America and Africa.


Assuntos
Plutônio/análise , Monitoramento de Radiação , Cinza Radioativa/análise , Poluentes Radioativos do Solo/análise , Urânio/análise , Chile , Armas Nucleares , África do Sul
14.
Isotopes Environ Health Stud ; 54(5): 451-462, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30081672

RESUMO

The monitoring and evaluation of radioactive content in samples of PM10 aerosols have been investigated. The specific radioactivity concentrations (SRC) of 234U, 235U, 238U and 232Th were determined using inductively coupled plasma-sector field mass spectrometry in 13 samples collected in Mexico City and 8 samples collected in Cuernavaca in the centre of Mexico. The SRC of the radioisotopes analysed in PM10 were larger than those reported in PM2.5. The enrichment factor was greater than 5, indicating anthropogenic influences in both sites. The activity ratios of these isotopes in the samples were determined. The 235U/238U ratio showed variations with respect to the natural value, while the 234U/238U and 232Th/238U ratios did not show any secular equilibrium in all sites, corroborating that the increase of uranium is not influenced by natural sources. The annual dose results obtained have no impact on health.


Assuntos
Aerossóis/análise , Poluentes Radioativos do Ar/análise , Tório/análise , Urânio/análise , Cidades , Monitoramento Ambiental/métodos , Espectrometria de Massas/métodos , México , Material Particulado/análise , Cinza Radioativa
15.
J Environ Radioact ; 192: 75-80, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29890360

RESUMO

Tea plantations may be strongly affected by radioactive fallout. Tea plantations on the Turkish coast of the Black Sea were heavily contaminated by the fallout from the reactor fire at the Chernobyl nuclear power plant in 1986. Two years later, the contamination level was reduced by about 90%. When tea is brewed, the original contamination in the tea leaves is more or less leached into the tea water. While most of the radiocaesium (60-80%) is washed out by brewing, most of the radiostrontium remains in the leaves (70-80%). In food laws, a dilution factor of 40-50 is considered for tea brewing. Most laws only define limit values for radiocaesium. Radiostrontium is not specially regulated, even though its dose coefficients for ingestion are higher than the corresponding coefficients for radiocaesium. Radiostrontium in tea occurs primarily from global fallout (bomb tests from 1945-1965).


Assuntos
Monitoramento de Radiação , Cinza Radioativa/análise , Poluentes Radioativos do Solo/análise , Chá/química , Armas Nucleares , Liberação Nociva de Radioativos , Turquia
16.
J Environ Radioact ; 186: 152-160, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29061309

RESUMO

There are very few data available of 236U in marine sediment cores. In this study we present the results from the first oceanic depth profile of 236U in a sediment core sampled in the North Atlantic Ocean, at the PAP site (4500 m depth, Porcupine Abyssal Plain (PAP) site, 49°0' N, 16°30' W). Additionally, the sediment core was radiologically characterized through the measurement of anthropogenic 137Cs, 239Pu, 240Pu, 129I and 14C and natural 210Pb, 40K and 226Ra. The measured 236U concentrations decrease from about 90·106 at g-1 at the seafloor down to 0.5·106 at g-1 at 6 cm depth. They are several orders of magnitude lower than the reported values for soils from the Northern Hemisphere solely influenced by global fallout (i.e. from 2700·106 to 7500·106 at g-1). 236U/238U atom ratios measured are at least three orders of magnitude above the estimated level for the naturally occurring dissolved uranium. The obtained inventories are 1·1012 at m-2 for 236U, 80 Bq m-2 for 137Cs, 45 Bq m-2 for 239+240Pu and 2.6·1012 at m-2 for 129I. Atomic ratios for 236U/239Pu, 137Cs/236U and 129I/236U, obtained from the inventories are 0.036, 0.11 and 2.5 respectively. Concentration profiles show mobilization probably due to bioturbation from the abundant detritivore holothurian species living at the PAP site sea-floor. The range of 236U, 137Cs, 239+240Pu and 129I values, inventories and ratios of these anthropogenic radionuclides are more similar to the values due to fall-out than values from a contribution from the Nuclear Fuel Reprocessing Plants dispersed to the south-west of the North Atlantic Ocean. However, signs of an additional source are detected and might be associated to the nuclear wastes dumped on the Eastern North Atlantic Ocean.


Assuntos
Sedimentos Geológicos/química , Cinza Radioativa/análise , Urânio/análise , Poluentes Radioativos da Água/análise , Oceano Atlântico , Monitoramento de Radiação
17.
Artigo em Inglês | MEDLINE | ID: mdl-28578647

RESUMO

BACKGROUND: On 26th April, 1986 the greatest accident of nuclear plant in Czernobyl occured and isotopes with high percentage of release were erupted: 33-Xe, 131-I, 132-Te, 134-Cs and 137-Cs. The radioactivity of the isotopes was very high - for instance: 33-Xe 6500 PBq, 131-I 1760 PBq. Rest of the 15 isotopes represented similar radioactivity with shorter percentage of release. The most exposed group of people were 237 liquidators, and 11600 people living around had to be evacuated when the limit dose for a person (5mSv) was crossed. Ionizing radiation on the molecular level produces high energy radicals, water radiolysis and ionization of the atoms leading to damage of the enzymes activity centers and receptors, cell membranes DNA, intracellular lysosomes, and especially important for ATP synthesis - mitochondria. These destructions lead to tissue and organs damage. OBJECTIVE: The aim of this article is the presentation of the protective property of iodine application in the case of nuclear accident. METHODS: In Poland at that time, effective iodine prophylaxis did not exist. In the face of such exposition, a special Governement Commission was appointed. When permissioned maximal dose for children and adolescents 50mSv appeared in some areas of the country, the Commission made a decision about obligatory administration of a single pharmacological dose of potassium iodide for all children and adolescents till age 16. No relevant recent patents were available for this WHO report. RESULTS: In this way, the dose of 131-I to thyroid for inhabitants in high, moderated, and low contaminated regions were reduced by about 45%. However, from 1987 to 1997 increase in prevalence of the differentiated thyroid cancer in adults in Polish population especially in women over 40 years old in the southern part of Poland was observed. CONCLUSION: Actually in European countries work 185 nuclear power plants and to 2045 another 100 is planned. In 1999, WHO issued recommendations on iodine prophylaxis in the case of nuclear accident.


Assuntos
Acidente Nuclear de Chernobyl , Suplementos Nutricionais , Exposição Ambiental/efeitos adversos , Neoplasias Induzidas por Radiação/prevenção & controle , Iodeto de Potássio/administração & dosagem , Exposição à Radiação/efeitos adversos , Cinza Radioativa/efeitos adversos , Neoplasias da Glândula Tireoide/prevenção & controle , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Política de Saúde , Humanos , Lactente , Recém-Nascido , Masculino , Neoplasias Induzidas por Radiação/diagnóstico , Neoplasias Induzidas por Radiação/epidemiologia , Polônia/epidemiologia , Prevalência , Fatores de Proteção , Fatores de Risco , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/epidemiologia , Fatores de Tempo
18.
J Environ Radioact ; 178-179: 349-353, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28526526

RESUMO

A slice from a Porites Lutea coral core collected inside the Enewetak Atoll lagoon, within 15 km of all major nuclear tests conducted at the atoll, was analysed for 236U, 239Pu and 240Pu over the time interval 1952-1964 using a higher time resolution than previously reported for a parallel slice from the same core. In addition two sediment samples from the Koa and Oak craters were analysed. The strong peaks in the concentrations of 236U and 239Pu in the testing years are confirmed to be considerably wider than the flushing time of the lagoon. This is likely due to the growth mechanism of the coral. Following the last test in 1958 atom concentrations of both 236U and 239Pu decreased from their peak values by more than 95% and showed a seasonal signal thereafter. Between 1959 and 1964 the weighted average of the 240Pu/239Pu atom ratio is 0.124 ± 0.008 which is similar to that in the lagoon sediments (0.129 ± 0.006) but quite distinct from the global fallout value of ∼0.18. This, and the high 239,240Pu and 236U concentrations in the sediments, provides clear evidence that the post-testing signal in the coral is dominated by remobilisation of the isotopes from the lagoon sediments rather than from global fallout.


Assuntos
Armas Nucleares , Plutônio/análise , Monitoramento de Radiação , Cinza Radioativa/análise , Urânio/análise , Poluentes Radioativos da Água/análise
19.
J Environ Radioact ; 169-170: 70-78, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28088697

RESUMO

The first extensive study on 236U in the North Pacific Ocean has been conducted. The vertical distribution of 236U/238U isotopic ratios and the 236U concentrations were analysed on seven depth profiles, and large variations with depth were found. The range of 236U/238U isotopic ratios was from (0.09 ± 0.03) × 10-10 to (14.1 ± 2.2) × 10-10, which corresponds to 236U concentrations of (0.69 ± 0.24) × 105 atoms/kg and (119 ± 21) × 105 atoms/kg, respectively. The variations in 236U concentrations could mainly be attributed to the different water masses in the North Pacific Ocean and their formation processes. Uranium-236 inventories on the water column of each sampling station were calculated and varied between (3.89 ± 0.08) × 1012 atoms/m2 and (7.03 ± 0.50) × 1012 atoms/m2, which is lower than in former studies on comparable latitudes in the North Atlantic Ocean and the Sea of Japan. The low inventories of 236U found for the North Pacific Ocean in this study can be explained by the lack of additional input sources of artificial radionuclides, apart from global and regional/local fallout. This study expands the use of 236U as oceanographic circulation tracer to yet another ocean basin and shows that this isotope can be used for tracing circulation patterns of water masses in the Pacific Ocean.


Assuntos
Monitoramento de Radiação , Cinza Radioativa/análise , Urânio/análise , Poluentes Radioativos da Água/análise , Japão , Oceano Pacífico
20.
Nat Prod Commun ; 12(2): 263-265, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30428227

RESUMO

In March, 2011, large amounts of radioactive materials were released from the Fukushima Daiichi nuclear power plant after the nuclear accident. Especially, for humans, internal exposure to ¹³7Cs and 9°Sr radionuclides presents very high risks because of their very long physical half-lives (¹³7Cs: 30.2 years, 9°Sr: 28.9 years). Therefore, it is important to inhibit the absorption of radioactive materials and to promote the excretion of them from the body through feces. The aim of this.study was to explore foods, their components and various chemicals showing adsorption properties to Cs and Sr. Sodium alginate (ALA-Na) strongly adsorbed Cs and Sr compared with other samples. Chondroitin sulfate, carboxymethyl cellulose sodium (CMC-Na), methyl cellulose (MC) and apple polyphenols (AP; high molecule weight) also showed adsorption potency to Cs in that order. For Sr adsorption, kelp, CMC-Na, MC, AP (high molecule weight), laminaran and Jew's mallow exhibited adsorbing effects in that order. These samples might be useful and safe tools to protect from the adverse effects induced by internal exposure to these radioactive materials.


Assuntos
Radioisótopos de Césio/química , Análise de Alimentos , Contaminação Radioativa de Alimentos/análise , Acidente Nuclear de Fukushima , Radioisótopos de Estrôncio/química , Adsorção , Cinza Radioativa
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