Comparing the effect of electron beam, beta and ultraviolet C exposure on the luminescence emission of commercial dosimeters.

This paper reports on the luminescence characterization of TLD-100 (LiF: Ti, Mg), TLD-200 (CaF2: Dy), TLD-400 (CaF2: Mn) and GR-200 (LiF: Mg, Cu, P) dosimeters exposed to electro beam, beta and ultraviolet C radiation -UVC-. All of them show high sensitivity to radiation regardless of whether it is ionizing or partially ionizing radiation based on their luminescence properties (cathodoluminescence -CL- or thermoluminescence -TL-). CL emission differs significantly among them in shape and intensity due to their chemical compositions. LiF samples display three maxima at: (i) 300-450 nm linked to intrinsic and structural defects, (ii) a green waveband probably due to F3+ centres or the presence of hydroxyl groups and (iii) the red-infrared emission band associated with F2 centres. However, CL spectra from the CaF2 dosimeters display meaningful differences due to the dopant. TLD-200 is characterized by an emission with four sharp individual peaks in the green-IR spectral region (due to the Dy3+), whilst TLD-400 exhibits a broad maximum peaked at Ì´500 nm (linked to the Mn2+). On the other hand, the variation in the TL glow curves allows to discriminate the TLDs exposed to beta and UVC radiation since they give rise to different chemical-physical processes and that have been studied from the estimation of the kinetic parameters by means of the Computerised Glow Curve Deconvolution (CGCD) method.

Characterization of Spanish honeys with protected designation of origin "Miel de Granada" according to their mineral content.

Honey attributes such as geographical origin or specified botanical sources often command a premium price due to their organoleptic or pharmacoactive properties. "Miel de Granada" is a highly quality product with protected designation of origin (PDO) which includes six monofloral honeys and two multifloral honeys. Our objective was the characterization of "Miel de Granada" according to their metal content. Metal content was specific enough and allowed discrimination from honeys of different botanical and geographical origins and confirmed the authenticity of PDO labelling as Granada product with the determination of only five elements (K, Na, Ca, Mg and Zn). Chemometric techniques as cluster analysis and ANOVA were used to classify honeys according to their botanical and geographical origin in the metal data. Metal content marks the differences in honey samples and can be used as a tool to assess the quality of honeys. ANOVA showed significant differences among rosemary honeys from different geographical areas despite the botanical factor weight. Our research contributes to the groundwork studies to determine the geographical origin of Spanish honeys.

Contenido hepático de mercurio y plomo en cormorán moñudo (Phalacrocorax aristotelis) y alcatraz atlántico (Morus bassanus) procedentes de las costas de Galicia (España) / Mercury an d lead hep atic con ten t in s hag (Phalacrocorax aristotelis) and gannet (Morus bassanus) from the Galician coast (Spain)

En el presente estudio se han analizado las concentraciones de dos metales pesados (Hg y Pb) en el tejido hepático de dos especies de aves marinas (cormorán moñudo, Phalacrocorax aristotelis, y alcatraz, Morus bassanus), empleando para ello animales aparecidos muertos o moribundos a lo largo de la costa de Galicia. Los ejemplares considerados fueron divididos en dos grupos en función de si habían sido afectados o no por la marea negra causada por el vertido del 'Prestige' en noviembre de 2002, a fin de determinar si dicho vertido había afectado al contenido metálico de estas especies. Tras la digestión de las muestras por vía húmeda, el contenido de ambos metales fue determinado por medio de voltamperometría de redisolución anódica (Pb) y de un analizador directo de mercurio (DMA) (Hg). Considerando la diferencia interespecífica para el Hg total, las concentraciones en cormorán moñudo (media: 4,2-7,6 ppm) fueron siempre mayores que en alcatraz (media: 1,6-1,8 ppm), con un valor máximo superior a 20 ppm (peso húmedo), correspondiente a un animal afectado por la marea negra. Con respecto al Pb, el resultado fue contrario, con niveles ligeramente superiores en los alcatraces con respecto a los cormoranes moñudos, pero en ningún caso superándose el nivel de 0,01 ppm (peso húmedo). Al considerar los dos grupos establecidos (afectados o no por el accidente del 'Prestige'), se pudo evidenciar que el vertido de crudo no afectó de una manera estadísticamente significativa a los niveles de ambos contaminantes metálicos en el tejido hepático de los animales considerados (AU)

At the present work, heavy metal (Hg and Pb) concentrations in hepatic tissue from two seabird species (shag, Phalacrocorax aristotelis, and gannet, Morus bassanus) have been analyzed, by using collected animals which died or were dying along the Galician coast (NW Spain). The considered animals were divided in two groups, considering if they had been affected or not by the oil spill caused by the 'Prestige' in November 2002, and in order to determine if such spill had modified the heavy metal content of such seabird species. After sample wet digestion, heavy metal content was determined using anodic stripping voltammetry (Pb) and direct mercury analyzer (DMA) (Hg). When considering inter-specific differences for total Hg, hepatic concentrations from shag samples (mean: 4.2-7.6 ppm) were higher than those from gannet (mean: 1.6-1.8 ppm), with a maximum value reaching up to 20 ppm (wet weight), corresponding to an animal affected by the oil spill. With regards to Pb content, results were different, with slightly higher levels from gannet samples than those from shag, but never exceeding 0.01 ppm (wet weight). When considering both established groups (affected or not by the 'Prestige' accident), it could be established that the oil spill did not affect on a statistically significant manner the levels of both metallic contaminants on the hepatic tissue of the considered animals (AU)