C. Galinha

Trace elements in wild and orchard honeys.

The present study aims the identification and quantification of trace elements in two types of honey samples: Orchard honey and Wild honey from mainland Portugal. Chemical elements content was assessed by Instrumental Neutron Activation Analysis (INAA). Concentrations were determinated for Ag, As, Br, Ca, Cl, Cs, Cu, Fe, K, La, Mg, Mn, Na, Rb, Sb, Sc, U, V and Zn. The nutritional values of both honey types were evaluated since this product contains some elements that are essential dietary nutrients for humans. Physical properties of the honey samples, such as electrical conductivy and pH, were assessed as well.

Assessment of the Portuguese k 0 -INAA laboratory performance by evaluating internal quality control data

The Portuguese INAA laboratory processes approximately one thousand of multi-matrix samples per year, generating fifteen thousands of results in the same period, using the k0 methodology. In order to ensure that the data produced meets the require quality any sample analysed is processed together with a reference material. Therefore, every year a large amount of results of many reference materials are generated. This work analysed a large database created with the results from the reference materials irradiated in the period 2009–2013. Zeta-scores were calculated and different control charts were created as function of the time period, irradiated mass, reference material and operator. The objective of this work was to recognise human errors, to identify deficiencies in the protocols and to improve the quality of the results generated by the laboratory.

Assessment of bioaccumulation of REEs by plant species in a mining area by INAA

Native plant species, lichens and tailings, sampled from a copper–sulphide mining area located in southern–eastern Portugal, were analysed by neutron activation analysis (INAA) for determination of rare earth elements (REEs). Values of ΣREEs and individual REEs concentration of tailing samples are higher than those of natural background concentrations. The higher values of REEs are found in modern slags and the mixture of oxidized gossan and sulphide disseminated country rocks when compared with the alluvial sediments contaminated by mine tailings. The total concentrations of light REEs are higher than those of heavy REEs in all tailing samples. Distribution patterns of PAAS-normalized REEs in mine tailings show slightly LREE enriched and flat HREE pattern with negative Eu anomaly. Lichens accumulated higher concentration of lanthanides than vascular plants. The elevated levels of REEs in lichen, native plant species and tailing samples reflect the contamination of REEs in São Domingos mining area. The Carlina corymbosa, Erica australis and Lavandula luisierra accumulated the higher amounts of La, Ce and other REEs than the other plant species grown in this mining area.

Neutron activation analysis of wheat samples

The deficiency of essential micronutrients and excess of toxic metals in cereals, an important food items for human nutrition, can cause public health risk. Therefore, before their consumption and adoption of soil supplementation, concentrations of essential micronutrients and metals in cereals should be monitored. This study collected soil and two varieties of wheat samples-Triticum aestivum L. (Jordão/bread wheat), and Triticum durum L. (Marialva/durum wheat) from Elvas area, Portugal and analyzed concentrations of As, Cr, Co, Fe, K, Na, Rb and Zn using Instrumental Neutron Activation Analysis (INAA) to focus on the risk of adverse public health issues. The low variability and moderate concentrations of metals in soils indicated a lower significant effect of environmental input on metal concentrations in agricultural soils. The Cr and Fe concentrations in soils that ranged from 93-117 and 26,400-31,300mg/kg, respectively, were relatively high, but Zn concentration was very low (below detection limit <22mg/kg) indicating that soils should be supplemented with Zn during cultivation. The concentrations of metals in roots and straw of both varieties of wheat decreased in the order of K>Fe>Na>Zn>Cr>Rb>As>Co. Concentrations of As, Co and Cr in root, straw and spike of both varieties were higher than the permissible limits with exception of a few samples. The concentrations of Zn in root, straw and spike were relatively low (4-30mg/kg) indicating the deficiency of an essential micronutrient Zn in wheat cultivated in Portugal. The elemental transfer from soil to plant decreases with increasing growth of the plant. The concentrations of various metals in different parts of wheat followed the order: Root>Straw>Spike. A few root, straw and spike samples showed enrichment of metals, but the majority of the samples showed no enrichment. Potassium is enriched in all samples of root, straw and spike for both varieties of wheat. Relatively to the seed used for cultivation, Jordão presented higher transfer coefficients than Marialva, in particular for Co, Fe, and Na. The Jordão and Marialva cultivars accumulated not statistically significant different concentrations of different metals. The advantages of using INAA are the multielementality, low detection limits and use of solid samples (no need of digestion).

Elemental characterization of bread and durum wheat by instrumental neutron activation analysis

Cereals are by far the most significant agricultural crops, not only due to the sheer amount of their gross-tonnage production and prevalence in human diets worldwide, but also as food vehicles of important items for human nutrition and wellness at large—proteins, dietary fibers and oligoelements, such as selenium, calcium, zinc and iron, to name just a few. Still, some micronutrients feature an uneven distribution in the upper continental crust, and thus in cultivation soils deriving therefrom. Whether soils have always been poor in an essential element, or have just become deprived of it by intensive farming, the result is the same: insufficient soil–plant transfer, feeble-to-nonexistent plant uptake, and, therefore, unsatisfactory dietary distribution of that element through the food chain. Countries that implemented corrective measures or programs of crop biofortification and consumer education have been successful in dealing with some micronutrients’ deficiencies. Given their relative weight in Portuguese diets, cereals are obvious candidates for crop-supplementation strategies that may contribute to an upgrade in the health status of the whole population. A good knowledge of element-baseline data for major cereal varieties (plants) and main production areas (soils) is a pre-requisite though. The present work was aimed at an elemental characterization of cereals and soils from relevant wheat-producing areas of mainland Portugal. This paper is focused on wheat samples—bread and durum wheats; Triticum aestivum L. (Farak and Jordão cultivars) and Triticum durum Desf. (Don Duro and Simeto cultivars), respectively—from the 2009 campaign, collected at Trás-os-Montes, Alto Alentejo and Baixo Alentejo (inland regions). Elemental concentrations were determined by instrumental neutron activation analysis (INAA; k0-variant), and assessed with the k0-IAEA software. Quality control was asserted through the analysis of NIST-SRM® 1567a (Wheat Flour), NIST-SRM® 1568a (Rice Flour) and GBW 07404 (Limy-yellow Soil). Results are discussed and compared to available data from abroad.

Selenium characterisation of the Portuguese bread-wheat archival collection

Abstract. Following the first morphological and taxonomic inventory of Portuguese wheat in 1933, an archival collection of representative varieties has been maintained, replanted and documented by the National Institute of Agricultural and Veterinary Research (INIAV), specifically by its division formerly known as the National Station for Plant Improvement (ENMP-Elvas, now INIAV-Elvas). The INIAV-Elvas wheat collection has always been an invaluable asset in studies of agronomic and/or genetic development of wheat lines, as well as providing a frame of reference for the nutritional evolution of Portuguese wheat crops. This work addresses the status of selenium (Se) in a pool of 46 accessions of bread wheat. Special attention is paid to the (low) levels of Se, for which wheat acts as an important source in human diets, with a view to curbing its deficiency in Portuguese cultivars through biofortification strategies. All grain samples were irradiated at the Portuguese Research Reactor, and total Se was determined through cyclic neutron activation analysis. Our results indicate that the best candidates for an improvement of Se contents in mature grains are cvv. Ideal, Ribeiro (b) and Ribeiro (a), and the worst candidates are cvv. Restauração, Galego Rapado and Rieti.