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1.
Environ Int ; 169: 107505, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36115249

RESUMEN

Anthropogenic release of tritium from nuclear facilities is expected to increase significantly in the coming decades, which may cause radiation exposure to humans through the contamination of water and food chains. It is necessary and urgent to acquire detailed information about tritium in various environments for studying its behavior and assessing the potential radiation risk. In the atmosphere, although the passive sampling technique provides a low-cost and convenient way to characterize the dynamics of tritiated water vapor (HTO), a single, simple sampler configuration makes it difficult to collect sufficient and representative samples within the expected period from different environments. In this study, we systematically studied the impacts of sampler configurations on sampling performance and proposed a modifiable sampler design by scaling sampler geometry and adjusting absorbent to achieve different monitoring demands. The samplers were subsequently deployed at five sites in China and Germany for the field calibration and the measured results exhibited a good agreement between the adsorption process obtained in sites corrected with diffusion coefficient and the one calibrated in Shanghai. This suggests the feasibility of predicting sampling performance in the field based on known data. Finally, we developed a strategy for sampler modification and selection in different environments and demonstrated that using easily obtainable environmental data, our sampler can be optimized for any area without any time-consuming preliminary experiments. This work provides a scientific basis for establishing high-resolution atmospheric HTO database and expands the conventional empirical sampler design paradigm by demonstrating the feasibility of using quantitative indices for sampler performance customization.


Asunto(s)
Monitoreo del Ambiente , Contaminantes Químicos del Agua , Calibración , China , Monitoreo del Ambiente/métodos , Humanos , Vapor , Tritio/análisis , Contaminantes Químicos del Agua/análisis
2.
Risk Anal ; 42(11): 2421-2439, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35871635

RESUMEN

Regulators and policymakers are routinely challenged with explaining complex concepts concerning risk. Part of the challenge is helping external and internal stakeholders to understand the context behind risk-related information and decisions. This paper will describe the historical evolution of the safety and regulatory framework for an important category in the nuclear industry-defense nuclear facilities owned and operated by the US Department of Energy. In parallel with describing this evolution, three major events which occurred external to the complex of defense nuclear facilities will be summarized, and their impact on the maturation of the Department's safety and regulatory framework will be discussed. Finally, integrated with these two threads of discussion will be a chronicle of the changing set of involved organizations and the expanding set of external stakeholders involved in risk decisions-and therefore, the risk communications ecosystem surrounding defense nuclear facilities. It will be noted that this system was once describable as a classic "iron triangle," but now has progressed to a complex network of federal and state organizations, numerous congressional committees, and expanding sets of external stakeholders. It is hoped that a comprehensive discussion of the context of risk assessment in the defense nuclear facilities complex-addressing historical insights, organizational evolution, and the maturing structure of regulation-will provide enhanced opportunities for building trust and understanding in this complex environment.


Asunto(s)
Comunicación , Ecosistema , Medición de Riesgo , Reactores Nucleares
3.
J Environ Radioact ; 212: 106129, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31885364

RESUMEN

Between October 2017 and May 2019, measurements of tritium in rainwater were carried out at several sites in north-west France. Tritium is an important tracer for hydroclimatic studies and this work provided up-to-date data that we compared with Global Network for Isotopes in Precipitation (GNIP) measurements. Of the various sites studied, some could potentially be affected by atmospheric gaseous emissions from the nuclear industries in the region (reprocessing plant, nuclear power plant). On our reference site, the activities measured in rainwater are often below the decision threshold (<0.15 Bq.L-1). Two other sites with little impact from nuclear industries have mean activities of less than 0.7 Bq.L-1. At the two Cherbourg sites closer to the nuclear industries, the activities in rainwater are slightly higher on average, though still close to 1 Bq.L-1, but the activities are more variable when the rainfall accompanies an air mass from the Orano La Hague nuclear site. Using existing GNIP data and a simple model to simulate predicted data up to 2019, it is shown that all our measured data are comparable with the predicted activities for GNIP stations with a marine influence, in the case of the reference site and the sites with little impact from nuclear industries, and for GNIP stations with a continental influence, in the case of the other sites. Seasonal variation in activities was detected, with greater activities in the spring-summer period corresponding to the well known 'spring leak' phenomenon. This study also reveals significant differences between the activities measured on the western side of France (influenced by the Atlantic Ocean) and those measured in a continental zone. The mean levels of tritium in rainwater in France, excluding any nuclear influence, can be estimated on average at less than 0.3 Bq.L-1 in the western marine zone, and at around 1 Bq.L-1 in the continental zones.


Asunto(s)
Monitoreo de Radiación , Contaminantes Radiactivos del Aire , Océano Atlántico , Francia , Tritio
4.
Nucleus (La Habana) ; (66): 32-38, jul.-dic. 2019. graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1091398

RESUMEN

RESUMEN En tributo a los cinco siglos de ciudad el Centro de Isótopos hace recuento de su actividad. La obtención de compuestos marcados con radionucleidos y otros trabajos radioquímicos en el Instituto de Física Nuclear, inaugurado en 1969, estimularon las aplicaciones de las fuentes radiactivas abiertas, por lo que puede considerarse el antecedente organizado más palpable del centro. Posteriormente en los años 80, la Secretaria Ejecutiva para Asuntos Nucleares aceleró, diversificó y amplió las aplicaciones, desarrolló la formación de cuadros y especialistas y la colaboración internacional. La puesta en operación del Centro de Estudios Aplicados al Desarrollo de la Energía Nuclear coincidió con la consolidación de un grupo de instituciones de investigación y producción biotecnológica y con el auge de las aplicaciones en Medicina Nuclear. Pronto se reconoció que no era posible continuar el manejo de un inventario cada vez mayor de radionucleidos, por lo que se diseñó y construyó un centro especializado a ciclo completo: investigación-desarrollo, producción y comercialización, el CENTIS. Durante su integración en 1994 a la Agencia de Energía Nuclear, se concluyó la inversión y se establecieron las metodologías de producción de los más importantes radiofármacos. En más de 20 años de labor CENTIS se ha convertido en el principal soporte de la Medicina Nuclear del país. Con sus capacidades metrológicas en la magnitud radiactividad y sus investigaciones no clínicas y clínicas, se inserta de forma cada vez más estrecha en la vida socio-económica del país y su capital. En el trabajo se detallan los principales resultados de cada etapa en lo relacionado a la misión del centro y se hace una valoración técnica de hacia dónde se encaminan acciones en favor de sus sectores destino: salud e investigación biomédica. Lustros en favor de siglos.


ABSTRACT To commemorate the 500th anniversary of the city of Havana, the Isotope Center reviews its activity since its creation. The production of radionuclidemarked compounds and other radiochemical work at the Institute of Nuclear Physics, inaugurated in 1969, stimulated the applications of open radioactive sources, which can be considered as the most tangible organized antecedent of the center. Later in the 1980s, the Executive Secretary for Nuclear Affairs accelerated, diversified and expanded nuclear applications, developed the training of highly qualified staff and experts as well as international cooperation. The creation of the Center for Applied Nuclear Development Studies coincided with the consolidation of a group of biotechnological research and production institutions and with these applications gaining importance in Nuclear Medicine. It was soon recognized that it was not possible to continue managing a growing inventory of radionuclides. As a result, CENTIS, a specialized center with a complete cycle, was designed and built, which comprised not only research and development, but also production and marketing. When in 1994 CENTIS became part of the Nuclear Energy Agency, investment was concluded and the production methodologies of the most important radiopharmaceuticals were established. In more than 20 years of work CENTIS has become the main support of Nuclear Medicine in the country. With its metrological capabilities in the magnitude of radioactivity and its non-clinical and clinical research, it is increasingly part of the socio-economic life of the country and its capital. In this paper the main results of each stage are detailed in relation to the mission of the center and a technical assessment is made regarding the actions taken to favor their target sectors: health and biomedical research. Periods of five years in favor of centuries.

5.
Environ Res ; 172: 586-595, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30875512

RESUMEN

Remediation of lands contaminated with radionuclides and hazardous chemicals provides an ongoing challenge for many countries. It is particularly problematic for remediation of old industrial sites remaining from World War II and the Cold War. Remediating and restoring large sites is often costly, time-consuming, and involves complex planning and sequencing, as well as consideration of future land use policies. The goal of remediation is to reduce contamination, reduce risk to humans and the environment, and restore land to productive land uses, and ultimately, to sustainability. Often reducing risk to people takes precedence over protecting ecological resources in overall planning, characterization, and execution of remediation strategies. This paper examines when and how stakeholders, including anyone interested and affected by remediation on ecological resources, can become involved in the planning, decision-making, and implementation of remediation. There is a formal process under federal law (e.g. CERCLA) in the US for examining risk to resources, including indicator species. However, there are other informal points during the cleanup process when managers should consider the value of ecological resources, the public may express their concerns for particular ecological resources, and ecologists may provide data and expert advice early in the process as critical decisions are being made about remediation that impact ecological resources. The framework presented in this paper for increasing sustainability of ecological resources has three periods of intervention 1) major decision points, 2) process interdiction points, and 3) remediation action points. Major decision points include site and problem identification, regional ecological resource and local land use practice determination, remediation goals and options determination, and other local issues. Interdiction points include examining remediation options, and in-depth assessments of ecological resources on-site. Remediation action points are aimed at reducing risk to ecological resources during remediation, and include defining the remediation site and buffer, understanding the effects of timing and sequencing of remediation, education of all remediation personnel, and specific suggestions for reducing risk during active remediation. While this framework was developed for Department of Energy remediation sites, it is applicable to brownfields and other contaminated lands world-wide. The overall goal is to provide interested and affected parties with a framework for protecting and enhancing ecological resources during the planning and execution of remediation on contaminated lands.


Asunto(s)
Ecología , Restauración y Remediación Ambiental , Residuos Industriales , Conducta de Reducción del Riesgo , Restauración y Remediación Ambiental/métodos , Sustancias Peligrosas , Humanos
6.
Environ Monit Assess ; 190(8): 478, 2018 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-30030638

RESUMEN

Many countries are faced with monumental cleanup tasks remaining from World War II and the Cold War and consistent methodologies are essential to assess the risk from pollutants and the risk from cleanup. In the USA, the Department of Energy (DOE), and other federal and state agencies need to be able to rapidly evaluate the risk to ecological resources for remediation projects. While ecological risk assessments for radionuclides and other contaminants can be performed for different species, evaluations of species assemblages, communities, and ecosystems is more difficult. We summarize an evaluation method for ecological resources on individual remediation units that will allow comparison among a large number of units and that can be modified and applied to the DOE complex-wide. We evaluated the deactivation and decommissioning (D & D) facilities at the Hanford site as case studies. Remediation of these sites has the potential to provide harm to, or increase the value of, ecological resources during and after the process. The evaluation method includes three categories: (1) general steps, (2) ecological descriptions, and (3) ecological ratings. The general steps include identifying the categories of resources (level of resource value), identifying the units to be evaluated (e.g., remediation units), identifying a reasonable ecological buffer around the evaluation units, identifying the remediation options (from milestones or other agreements), and developing a rating scale. Ecological descriptions include identifying previous ecological values of specific areas on the evaluation unit, conducting field studies to assess the current conditions, and summarizing the percent of each resource value on the evaluation unit and buffer area. The ecological risk of harm is determined by using the rating scale to evaluate the potential harm to the ecological (and eco-cultural) resources on each evaluation unit currently, during remediation, and in the post-remediation phase. Currently, the risks (potential harm) to ecological resources on the D & D facilities at the Hanford site are non-discernible, but they increase to very high (for reactors) during remediation when there is physical disruption, increased traffic and personnel, and possible increased contamination. Following remediation, the potential harm to ecological resources is low, and the value may be increased due to restoration of native vegetation on sites that were largely industrial prior to remediation. These methods provide managers, regulators, tribes, and the general public with assurance that ecological and eco-cultural resources and the environment are being protected during and following remediation.


Asunto(s)
Monitoreo del Ambiente/métodos , Restauración y Remediación Ambiental/métodos , Sustancias Peligrosas/análisis , Residuos Peligrosos/análisis , Animales , Ecología/métodos , Ecosistema , Contaminantes Ambientales/análisis , Contaminación Ambiental/análisis , Agencias Gubernamentales , Radioisótopos/análisis , Medición de Riesgo , Porcinos
7.
J Environ Radioact ; 189: 67-78, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29625370

RESUMEN

Ambient gamma dose, radon, and rainfall have been monitored in southern Bucharest, Romania, from 2010 to 2016. The seasonal cycle of background ambient gamma dose peaked between July and October (100-105 nSv h-1), with minimum values in February (75-80 nSv h-1), the time of maximum snow cover. Based on 10 m a.g.l. radon concentrations, the ambient gamma dose increased by around 1 nSv h-1 for every 5 Bq m-3 increase in radon. Radon variability attributable to diurnal changes in atmospheric mixing contributed less than 15 nSv h-1 to the overall variability in ambient gamma dose, a factor of 4 more than synoptic timescale changes in air mass fetch. By contrast, precipitation-related enhancements of the ambient gamma dose were 15-80 nSv h-1. To facilitate routine analysis, and account in part for occasional equipment failure, an automated method for identifying precipitation spikes in the ambient gamma dose was developed. Lastly, a simple model for predicting rainfall-related enhancement of the ambient gamma dose is tested against rainfall observations from events of contrasting duration and intensity. Results are also compared with those from previously published models of simple and complex formulation. Generally, the model performed very well. When simulations underestimated observations the absolute difference was typically less than the natural variability in ambient gamma dose arising from atmospheric mixing influences. Consequently, combined use of the automated event detection method and the simple model of this study could enable the ambient gamma dose "attention limit" (which indicates a potential radiological emergency) to be reduced from 200 to 400% above background to 25-50%.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Contaminación Radiactiva del Aire/estadística & datos numéricos , Monitoreo de Radiación , Radón/análisis , Rayos gamma , Dosis de Radiación , Rumanía
8.
J Environ Radioact ; 178-179: 253-264, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28917181

RESUMEN

Knowledge of the background activity concentrations of anthropogenic radionuclides before the start of operations of the new nuclear facilities in Belarus is of great value worldwide. Inland water bodies in Lithuania (specifically the Neris River, the Nemunas River and the Curonian Lagoon) are near the site of the Belarusian NPP under construction and, for this reason, sediments and flooded soils from these sensitive areas were analysed for radiocesium and plutonium isotopes (macrophytes were analysed only for 137Cs) in 2011-2012. The 137Cs and 239+240Pu activity concentrations in bottom sediments from the Nemunas River, sampled in 1995-1996 and re-calculated to the year 2016, were compared with those of 2011-2012. The obtained activity of 137Cs in bottom sediments of the Nemunas River and Curonian Lagoon varied from 1 Bq/kg to 47.0 Bq/kg. The activity of 137Cs in the tested soils ranged from 5.3 B g/kg to 32.9 Bq/kg. The 239+240Pu activity in bottom sediments of the studied sampling sites varied between 0.016 and 0.34 Bq/kg and in flooded soils from 0.064 to 0.55 Bq/kg. The 238Pu activity values were very low or lower than the detection limit. The activity of 137Cs in macrophytes varied from values lower than the detection limit to 6 Bq/kg. A strong positive linear correlation for bottom sediments was calculated between: 239+240Pu and total organic carbon (TOC), r = 0.86, p-value 0.01; 239+240Pu and silt, r = 0.80, p-value 0.029; 137Cs and silt, r = 0.78, p-value 0.04; and 137Cs and TOC, r = 0.85, p-value 0.015. The similar peculiarities of 137Cs and 239+240Pu accumulation in bottom sediments and flooded soil allow us to assume that 137Cs can be used as a tracer for 239+240Pu in the initial stage of searching for radionuclide accumulation zones. A remaining impact of the Chernobyl fallout in average comprised: in the Lower Nemunas River and Curonian Lagoon sediments - 51%, in the Middle Nemunas River -90% and in the floodplains of the Nemunas River - 59%, while the provenance of plutonium in studied bottom sediments and flooded soil was the global fallout.


Asunto(s)
Radioisótopos de Cesio/análisis , Contaminantes Radiactivos del Agua/análisis , Sedimentos Geológicos/química , Lituania , Plantas de Energía Nuclear , Monitoreo de Radiación , Ceniza Radiactiva/análisis , República de Belarús , Ríos , Contaminantes Radiactivos del Suelo/análisis
9.
Radiat Environ Biophys ; 56(1): 111-120, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28035471

RESUMEN

Health effects of close residential proximity to nuclear facilities have been a concern for both the general public and health professionals. Here, a study is reported examining the association between maternal residential proximity to nuclear facilities and low birth weight (LBW) in offspring using data from 1996 through 2008 in Texas, USA. A case-control study design was used together with a proximity-based model for exposure assessment. First, the LBW case/control births were categorized into multiple proximity groups based on distances between their maternal residences and nuclear facilities. Then, a binary logistic regression model was used to examine the association between maternal residential proximity to nuclear facilities and low birth weight in offspring. The odds ratios were adjusted for birth year, public health region of maternal residence, child's sex, gestational weeks, maternal age, education, and race/ethnicity. In addition, sensitivity analyses were conducted for the model. Compared with the reference group (more than 50 km from a nuclear facility), the exposed groups did not show a statistically significant increase in LBW risk [adjusted odds ratio (aOR) 0.91 (95% confidence interval (CI): 0.81, 1.03) for group 40-50 km; aOR 0.98 (CI 0.84, 1.13) for group 30-40 km; aOR 0.95 (CI 0.79, 1.15) for group 20-30 km; aOR 0.86 (CI 0.70, 1.04) for group 10-20 km; and aOR 0.98 (CI 0.59, 1.61) for group 0-10 km]. These results were also confirmed by results of the sensitivity analyses. The results suggest that maternal residential proximity to nuclear facilities is not a significant factor for LBW in offspring.


Asunto(s)
Vivienda , Recién Nacido de Bajo Peso , Exposición Materna/efectos adversos , Plantas de Energía Nuclear , Exposición a la Radiación/efectos adversos , Femenino , Humanos , Masculino , Embarazo , Texas , Factores de Tiempo
10.
Early Hum Dev ; 91(12): 841-50, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26527392

RESUMEN

It has long been known that ionizing radiation causes genetic mutations and that nuclear bomb testing, nuclear accidents, and the regular and incidental emissions of nuclear facilities enhance environmental radioactivity. For this reason, the carcinogenic and genetic impact of ionizing radiation has been an escalating issue for environmental health and human health studies in the past decades. The Windscale fire (1957) and the Chernobyl accident (1986) caused alterations to the human birth sex ratio at national levels across Europe, and childhood cancer and childhood leukemia are consistently elevated near nuclear power plants. These findings are generalized and corroborated by the observation of increased sex ratios near nuclear facilities in Austria, France, Germany, Luxembourg, Switzerland, and The Netherlands. We present a concise review of the pertinent literature and we complement our review by spatiotemporal analyses of historical and most recent data. Evidence of genetic damage by elevated environmental radioactivity is provided.


Asunto(s)
Radiación Ionizante , Liberación de Radiactividad Peligrosa , Razón de Masculinidad , Accidente Nuclear de Chernóbil , Exposición a Riesgos Ambientales , Femenino , Humanos , Recién Nacido , Masculino , Parto
11.
Anon.
Nucleus (La Habana) ; (56): 5-16, jul.-dic. 2014.
Artículo en Español | LILACS | ID: lil-745155

RESUMEN

En el presente artículo se resume una perspectiva histórica de la experiencia nacional en el desarrollo de la Física Nuclear, con énfasis especial en su vínculo con el Programa Nuclear Cubano,y los resultados científicos tecnológicos y de impacto socioeconómico obtenidos. Para sustentar el desarrollo de la nucleoenergética e instalaciones nucleares, se recoge la creación de instituciones especializadas, la formación de profesionales y de colectivos interdisciplinarios de físicos nucleares, teóricos, experimentadores, ingenieros y de otras especialidades. También se abordan las múltiples aplicaciones pacíficas introducidas en el país y en particular las asociadas al programa científico nuclear...


The present article summarizes an historical perspective of the national experience in Nuclear Physics development, with particular emphasis on its relationship with the Cuban Nuclear Program, its scientific and technological achievements, and its social and economic impact. Multiple peaceful applications introduced in the country and specifically those related to the Nuclear Power Program are also included. In order to support nuclear energy as well as nuclear power plants, specialized institutions were created, in addition to the training of professionals and interdisciplinary research groups in theoretical and experimental nuclear physics, engineering and in other different specialties...

12.
China Medical Equipment ; (12): 2-4, 2014.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-443348

RESUMEN

Objective: To provide reference for on-site medical emergency preparedness and response to nuclear facilities of our country. Methods: On the basis of laws, regulations and standards as well as our experience and research in this field. Results: To provide effective advice for on-site medical emergency preparedness and response. Conclusion:Introduce unclear accident influence, unclear accident emergency system and so on.

13.
Indian J Occup Environ Med ; 12(3): 122-7, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20040970

RESUMEN

Safety in nuclear power plants (NPPs) in India is a very important topic and it is necessary to dissipate correct information to all the readers and the public at large. In this article, I have briefly described how the safety in our NPPs is maintained. Safety is accorded overriding priority in all the activities. NPPs in India are not only safe but are also well regulated, have proper radiological protection of workers and the public, regular surveillance, dosimetry, approved standard operating and maintenance procedures, a well-defined waste management methodology, proper well documented and periodically rehearsed emergency preparedness and disaster management plans. The NPPs have occupational health policies covering periodic medical examinations, dosimetry and bioassay and are backed-up by fully equipped Personnel Decontamination Centers manned by doctors qualified in Occupational and Industrial Health. All the operating plants are ISO 14001 and IS 18001 certified plants. The Nuclear Power Corporation of India Limited today has 17 operating plants and five plants under construction, and our scientists and engineers are fully geared to take up many more in order to meet the national requirements.

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