101 research outputs found
Two significant experiences related to radon in a high risk area in Spain
Número monográfico dedicado al "Proceedings of the International Conference Radon in Environment 2009”Radon is a natural radioactive gas and it is currently accepted as being responsible for lung cancer in some cases. One of the most important sources of indoor radon is from the soil. The radium content of soil is also a very important factor to be taken into account. The natural radiation map of Spain (MARNA) classifies the country into three regions with different levels of natural gamma radiation. There are some areas in Spain with high levels of natural radiation one of those is the province of Salamanca. Western part of this province presents a population of 20 000 inhabitants and 7% of the houses have an indoor radon concentration above 400 Bq•m–3. In this high risk area, the village of Villar de la Yegua is of special interest: 11% of the houses in this village have an indoor radon level below 400 Bq•m–3, 89% have above 400 Bq•m–3 and 71% of the houses have a radon concentration above 1000 Bq•m–3. An old uranium mine site close to this village has been selected for the construction of an experimental pilot house. It is a two
story house located in the place with a very high 226Ra concentration in soil. Radon in soil at 1 m depth has an average level of 250 kBq•m–3. We present in this work the characteristics of the experimental unit located in this high risk area and we describe the zone where one of the Spanish villages with the highest radon concentration is located. This is a very interesting place for further research on indoor radon concentration and it is a unique opportunity of testing radón monitors, radon passive detectors and remedial actions for the mitigation of radon in real conditions. It is common to carry out intercomparison exercises under laboratory conditions. Nonetheless, it is not so common to develop these exercises in real conditions as we have in the experimental unit we present here. We offer in this work the possibility for other research groups of testing their equipments in this unit and we also show the evolution of the works carried out in the locality of Villar de la Yegua
Perfil de compuestos fenólicos y actividad antioxidante de Rhynchostele rossii (Orchidaceae) silvestre y cultivada in vitro
Background and Aims: Rhynchostele rossii is an orchid native to Mexico known as gallinitas (little chickens) that is threatened due to overexploitation for ornamental purposes, as a consequence of which it is necessary to realize efforts for its conservation. To date there are no reports of phytochemical studies of this orchid, although it is well known that species of the Orchidaceae family are a good source of bioactive and nutraceutical compounds (e. g. vanillin). Therefore, the main objective of this research was to establish a R. rossii in vitro germination protocol for propagation and determination of phenolic compounds that contribute to its phytochemical knowledge.Methods: A specimen of a wild plant and some seedlings obtained by in vitro culture were dried, milled and their components extracted with MeOH; anti-free radical activity (DPPH), total phenols and flavonoids were determined by spectrophotometric methods, and individual phenolic compounds were identified and quantified by liquid chromatography coupled to mass spectrometry (LC-MS).Key results: The root of the wild plant showed the highest content of total phenols and flavonoids with 121.60 mg GAE g-1 and 108.73 mg CE g-1, respectively, and the best anti-free radical activity with an IC50 53.63 μg ml-1. Extracts from seedlings obtained by in vitro culture also produced phenolic compounds, showing a total phenolic and flavonoid content of 37.35 mg GAE g-1 and 0.16 mg CE g-1, respectively. One coumarin (scopoletin) , three cinnamic acids (4-coumaric acid, ferulic acid and trans-cinnamic acid), three benzoic acids (vanillic acid, vanillin and 4-hydroxybenzoic acid) and three flavonoids (quercetin-3-D-galactoside, quercetin-3-glucoside and kaempferide) were identified and quantified by LC-MS.Conclusions: This study demonstrates that R. rossii is a potential source of antioxidant metabolites that can be obtained by in vitro culture, without harming the wild specimens.Antecedentes y Objetivos: Rhynchostele rossii es una orquídea nativa de México conocida como gallinitas, que está amenazada debido a su sobreexplotación con fines ornamentales, lo que hace necesario realizar esfuerzos para su conservación. A la fecha, no hay estudios fitoquímicos de esta orquídea, aunque se sabe que las especies de la familia Orchidaceae son una buena fuente de compuestos bioactivos y nutracéuticos (p. ej. vainillina). Por lo anterior, el objetivo principal de esta investigación fue establecer el protocolo de geminación in vitro de R. rossii para la propagación de la especie y la determinación de compuestos fenólicos que contribuyan al conocimiento fitoquímico de esta planta.Métodos: Un ejemplar silvestre y algunas plántulas obtenidas por cultivo in vitro se secaron, molieron y extrajeron con MeOH; se determinó la actividad de anti-radicales libres (DPPH), fenoles y flavonoides totales por métodos espectrofotométricos y algunos fenoles se identificaron y cuantificaron por cromatografía de líquidos acoplada a espectrometría de masas (LC-MS).Resultados clave: La raíz de la planta silvestre mostró el mayor contenido de fenoles y flavonoides totales con 121.60 mg GAE g-1, y 108.73 mg CE g-1, respectivamente, y la mejor actividad anti-radicales libres con una IC50 de 53.63 μg ml-1. Los extractos de las plántulas obtenidas in vitro también produjeron compuestos fenólicos, mostrando un contenido de fenoles y flavonoides totales de 37.35 mg GAE g-1 y 0.16 mg CE g-1, respectivamente, mientras que por LC-MS se identificaron y cuantificaron una cumarina (escopoletina), tres ácidos cinámicos (ácido 4-cumárico, ácido ferúlico y ácido trans-cinamico), tres ácidos benzoicos (ácido vainillico, vainillina y acido 4-hidroxibenzoico) y tres flavonoides (quercetina-3-D-galactósido, quercetina-3-glucósido y kaempferide).Conclusiones: Este estudio muestra que R. rossii es una fuente potencial de metabolitos antioxidantes que pueden obtenerse mediante cultivo in vitro, sin perjudicar a los ejemplares silvestres
A simple national intercomparison of radon in water
Radon-222, a naturally occurring radioactive gas, responsible together with its progeny of around 50% of the average effective dose received by the population, has not been regulated by law until the recent Directive 2013/51 /Euratom. Its transposition into Spanish legislation was made in the recent RD 314/2016, which sets at limit value of 500 Bq l¯¹ for radon-222 in water for human consumption. Intercomparison exercises, such as those carried out by IPROMA SL and the Laboratory of Environmental Radioactivity of the Cantabria University (LARUC) in November 2015 and December 2016, represent the most useful tool available for detecting problems and taking corrective actions necessary for an efficient measurement by part of the laboratories. The participants in these exercises used three techniques: liquid scintillation counting, gamma spectrometry and desorption followed by ionisation chamber detection
The Laboratory of Natural Radiation (LNR) - a place to test radon instruments under variable conditions of radon concentration and climatic variables
The publication of the new European Union Basic Safety Standards represents a remarkable milestone
in the fi eld of radiological protection in terms of adding radon exposure to this framework. Therefore, the
coming years will bring the need to measure radon not only in the workplaces but also in the living spaces as
a direct outcome of the application of the new EU Directive. So, the importance of having reliable instruments
is evident and interlaboratory exercises are becoming more and more popular. However, most of them are carried
out under constant conditions of meteorological variables. We present in this paper a facility to broaden the
interlaboratory comparisons further by adding the study of radon exposures under real conditions of changes in
climatic parameters. In addition, the facility has the possibility to verify the response of radon monitors when
the radon concentration changes several orders of magnitude in a short period of time. Our work shows some
results of one of the interlaboratory exercises carried out in the premises, where the radon levels were rather
homogeneous in the testing room
Radioactivity in drinking water
Número monográfico dedicado al X Congreso Español y I Congreso Iberoamericano de Sanidad Ambiental celebrado los días 28, 29 y 30 de octubre de 2009 en A Coruña.[ES]La directiva europea sobre calidad en el agua potable del año 2003 estableció los límites para los valores de los parámetros radiactivos. Esta directiva europea fue incorporada a la legislación 2003. Los parámetros a analizar son los índices alfa y beta total, el contenido en tritio y la dosis indicativa total. El correspondiente real decreto, en el caso de España, se comenzó a aplicar en el año 2008. No solamente el agua potable procedente de captaciones públicas está sujeta a control, sino que también se deben controlar las aguas comerciales. En ambos casos se han llevado a cabo estudios en todo el mundo. Existe un rango amplio de técnicas para la medida de la radiactividad en el agua de consumo. Este artículo describe tales técnicas e indica cuando se debe aplicar cada una de ellas. Por último, se muestran los resultados más importantes obtenidos tras el análisis de aguas potables y comerciales, tanto en aguas españolas como de fuera de España. Los resultados muestran que se superan los límites en algunos casos y por lo tanto se debe prestar especial atención a fin de reducir los niveles de radiactividad en las aguas potables todo lo posible.[EN]The European Directive on the quality of drinking water in 2003 establishing limits on the values of the radioactive parameters concerning the quality of drinking waters was translated to the Spanish legislation
on 2003. These parameters are the gross alpha and beta indexes, tritium content and total indicative dose. The corresponding Spanish Royal Decree came into force in 2008. Not only tap drinking water is subjected to control of radioactivity but also commercial drinking water. Different estudies have been carried out all over the world in both cases. There is a wide range of techniques for the measurement of radioactivity in water. This article describes these techniques and shows when they must be applied. Finally the most important results obtained after analysis in tap water and commercial water are shown both in Spanish and non-Spanish waters. The results show that limits are overtaken in some cases and special care must be taken in order to reduce the levels of radioactivity in drinking water as much as possible
Radiactividad en aguas de consumo
The European Directive on the quality of drinking water in 2003 establishing limits on the values of the radioactive parameters concerning the quality of drinking waters was translated to the Spanish legislation on 2003. These parameters are the gross alpha and beta indexes, tritium content and total indicative dose. The corresponding Spanish Royal Decree came into force in 2008. Not only tap drinking water is subjected to control of radioactivity but also commercial drinking water. Different estudies have been carried out all over the world in both cases. There is a wide range of techniques for the measurement of radioactivity in water. This article describes these techniques and shows when they must be applied. Finally the most important results obtained after analysis in tap water and commercial water are shown both in Spanish and non-Spanish waters. The results show that limits are overtaken in some cases and special care must be taken in order to reduce the levels of radioactivity in drinking water as much as possible.La directiva europea sobre calidad en el agua potable del año 2003 estableció los límites para los valores de los parámetros radiactivos. Esta directiva europea fue incorporada a la legislación 2003. Los parámetros a analizar son los índices alfa y beta total, el contenido en tritio y la dosis indicativa total. El correspondiente real decreto, en el caso de España, se comenzó a aplicar en el año 2008. No solamente el agua potable procedente de captaciones públicas está sujeta a control, sino que también se deben controlar las aguas comerciales. En ambos casos se han llevado a cabo estudios en todo el mundo. Existe un rango amplio de técnicas para la medida de la radiactividad en el agua de consumo. Este artículo describe tales técnicas e indica cuando se debe aplicar cada una de ellas. Por último, se muestran los resultados más importantes obtenidos tras el análisis de aguas potables y comerciales, tanto en aguas españolas como de fuera de España. Los resultados muestran que se superan los límites en algunos casos y por lo tanto se debe prestar especial atención a fin de reducir los niveles de radiactividad en las aguas potables todo lo posible
Radioactivity in drinking water
Número monográfico dedicado al X Congreso Español y I Congreso Iberoamericano de Sanidad Ambiental celebrado los días 28, 29 y 30 de octubre de 2009 en A Coruña.[ES]La directiva europea sobre calidad en el agua potable del año 2003 estableció los límites para los valores de los parámetros radiactivos. Esta directiva europea fue incorporada a la legislación 2003. Los parámetros a analizar son los índices alfa y beta total, el contenido en tritio y la dosis indicativa total. El correspondiente real decreto, en el caso de España, se comenzó a aplicar en el año 2008. No solamente el agua potable procedente de captaciones públicas está sujeta a control, sino que también se deben controlar las aguas comerciales. En ambos casos se han llevado a cabo estudios en todo el mundo. Existe un rango amplio de técnicas para la medida de la radiactividad en el agua de consumo. Este artículo describe tales técnicas e indica cuando se debe aplicar cada una de ellas. Por último, se muestran los resultados más importantes obtenidos tras el análisis de aguas potables y comerciales, tanto en aguas españolas como de fuera de España. Los resultados muestran que se superan los límites en algunos casos y por lo tanto se debe prestar especial atención a fin de reducir los niveles de radiactividad en las aguas potables todo lo posible.[EN]The European Directive on the quality of drinking water in 2003 establishing limits on the values of the radioactive parameters concerning the quality of drinking waters was translated to the Spanish legislation
on 2003. These parameters are the gross alpha and beta indexes, tritium content and total indicative dose. The corresponding Spanish Royal Decree came into force in 2008. Not only tap drinking water is subjected to control of radioactivity but also commercial drinking water. Different estudies have been carried out all over the world in both cases. There is a wide range of techniques for the measurement of radioactivity in water. This article describes these techniques and shows when they must be applied. Finally the most important results obtained after analysis in tap water and commercial water are shown both in Spanish and non-Spanish waters. The results show that limits are overtaken in some cases and special care must be taken in order to reduce the levels of radioactivity in drinking water as much as possible
Calculation of Response matrix of a BSS with 6LiI scintillator
The response matrix of a Bonner sphere spectrometer was calculated using MCNP 4C and MCNPX 2.4.0 codes. As thermal neutron detector a 0.4 cm £; 0.4 cm 6LiI which is located at the center of a set of polyethylene spheres. The response was calculated for 0, 2, 3, 5, 8, 10, and 12 inches-diameter polyethylene spheres for neutrons whose energy goes from 2.50E(-8) to 100 MeV. The response matrix was calculated for 23 neutron energies, the response functions were energy-interpolated to 51 neutron energies and were compared with a matrix response reported in the literature, in this comparison both response matrices are in agreement. The main differences were found in the bare detector and are attributed to the irradiation conditions and cross sections, for the other detectors the differences are due to the cross sections libraries
Spanish experience on the design of radon surveys based on the use of geogenic information
One of the requirements of the recently approved EU-BSS (European Basic Safety Standards Directive, EURATOM, 2013) is the design and implementation of national radon action plans in the member states (Annex XVIII). Such plans require radon surveys. The analysis of indoor radon data is supported by the existing knowledge about geogenic radiation. With this aim, we used the terrestrial gamma dose rate data from the MARNA project. In addition, we considered other criterion regarding the surface of Spain, population, permeability of rocks, uranium and radium contain in soils because currently no data are available related to soil radon gas concentration and permeability in Spain. Given that, a Spanish radon map was produced which will be part of the European Indoor Radon Map and a component of the European Atlas of Natural Radiation. The map indicates geographical areas with high probability of finding high indoor radon concentrations. This information will support legislation regarding prevention of radon entry both in dwellings and workplaces. In addition, the map will serve as a tool for the development of strategies at all levels: individual dwellings, local, regional and national administration
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