Search results for "Trace elements"
showing 10 items of 165 documents
Influence of nutritional variables on the onset of necrotizing enterocolitis in preterm infants: A case-control study.
2016
• Minimal enteral feeding should be early initiated and prolonged for at least 5–7 days in the most immature newborn.
Preliminary study on trace metal content in manna extracted from Fraxinus angustifolia cultivars in Madonie (Sicily, Italy)
2019
The manna is a product obtained from the elaborate sap solidification that comes out from the incisions made on the stem of some species of the genus Fraxinus L. In this study, we have analyzed 12 samples of manna to determine the chemical composition. Twenty elements (Al, As, Ba, Cd, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Pb, Rb, Sb, Se, Sr, U, V, Zn) were determined using an Inductively Coupled Plasma Mass Spectrometer. The results show that the most abundant elements are Fe > Rb > Al > Cu > Ba > Zn > Sr with median concentrations in the range of 0.9 – 10mg kg-1. The remaining elements exhibit median concentrations in the range of 0.0003 -0.5 mg kg-1. The manna also can be cons…
Chronological records of metal deposition in sediments from the Strait of Sicily, central Mediterranean: assessing natural fluxes and anthropogenic a…
2010
Abstract Sediment box-cores were recovered from the Strait of Sicily along two onshore–offshore transects in water depths of 29–500 m. Samples were dated by 210 Pb and analysed for major and trace elements. Inspections of chronological profiles integrated with application of statistical algorithms to the geochemical dataset and supported by in situ hydrological observations were used to assess factors driving element distributions. Mineralogical and chemical variability of sediments offshore of the southwestern Sicily coast reflect the irregular sea floor morphology of the Adventure Bank. Anthropogenic inputs explain enrichments with respect to background values for Sb, As, Pb, and Hg, that…
Trace element accumulation and elutriate toxicity in surface sediment in northernTunisia (Tunis Gulf, southern Mediterranean)
2017
International audience; Metal concentrations in sediments were investigated in the Gulf of Tunis, Tunisia, in relation to anthropic activities along the Mejerda River and Ghar El Melh Lagoon, with effluents discharged into the gulf. Distribution of grain size showed that the silty fraction is dominant with 53%, while sand and clay averages are 34 and 12% respectively. Zn concentration increased in the vicinity of the Mejerda River while Pb was at its highest levels at the outlet of Ghar El Mehl Lagoon. Sediment elutriate toxicity, as measured by oyster embryo bioassays, ranged from 10 to 45% abnormalities after 24 h, but no relation was found between metal concentration and sediment toxicit…
Gull-derived trace elements trigger small-scale contamination in a remote Mediterranean nature reserve
2013
The role of a yellow-legged gull (Larus michahellis) small colony in conveying trace elements (As, Cd, Cr, Cu, Ni, Pb, THg, V, Zn) was assessed in a Mediterranean nature reserve (Marinello ponds) at various spatial and temporal scales. Trace element concentrations in guano were high and seasonally variable. In contrast, contamination in the ponds was not influenced by season but showed strong spatial variability among ponds, according to the different guano input. Biogenic enrichment factor B confirmed the role of gulls in the release of trace elements through guano subsidies. In addition, comparing trace element pond concentrations to the US NOAA’s SQGs, As, Cu and Ni showed contamination …
Spatial relations of heavy metals in arable and greenhouse soils of a Mediterranean environment region (Spain)
2013
This study characterises and compares Cr, Ni, Pb, Cu, Zn and Cd (HMs) contents and the main edaphic parameters in arable soils (AS) from western areas of the Andalusian Autonomous Community (SE Spain) with greenhouse soils (GS) from the province of Almería, one of the most productive agricultural systems in Europe. We explored 199 GS and 142 AS, representing local and regional scales of variation in this important Mediterranean area. The hazardousness of HMs was particularly relevant in GS where agricultural practices, which centre on maximising production, end up with products that finally enter the human food chain directly. Despite their similar edaphic characteristics, the main differen…
Trace elements release from volcanic ashes to seawater. Natural concentrations in Central Mediterranean sea.
2009
Distributions and concentrations of many minor and trace elements in epicontinental basins, as Mediterranean Sea, are mainly driven to atmospheric fallout from surroundings. This mechanism supplies an estimated yearly flux of about 1000 kg km-2 of terrigenous matter of different nature on the whole Mediterranean basin. Dissolution of these materials and processes occurring at solid-liquid interface along the water column drive the distributions of many trace elements as V, Cr, Mn, Co, Cu, and Pb with contents ranging from pmol l-1 (Co, Cd, Pb) to nmol l-1 scale in Mediterranean seawater, with some local differences in the basin. The unwinding of an oceanographic cruise in the coastal waters…
Metabolite and mineral profiling of “Violetto di Niscemi” and “Spinoso di Menfi” globe artichokes by 1H-NMR and ICP-MS
2016
Globe artichoke has been long considered a nutraceutical food for its valuable content of bioactive compounds. However, beside a well-known polyphenol profile, poor information is available about its metabolite and mineral composition. The aim of this study was to investigate edible parts of Sicilian artichokes, ‘Spinoso di Menfi’ and ‘Violetto di Niscemi’, by 1H NMR and ICP-MS for elucidating these compositional aspects. Although bracts and hearts of both artichokes shared a very similar metabolite pattern, ‘Spinoso di Menfi’ showed a higher number of metabolites, such as amino acids and polyphenols, than ‘Violetto di Niscemi’. ‘Spinoso di Menfi’ was also marked by higher levels of macro- …
Characterization of trace elements in thermal and mineral waters of Greece
2023
: Natural thermal and mineral waters are widely distributed along the Hellenic region and are related to the geodynamic regime of the country. The diverse lithological and tectonic settings they are found in reflect the great variability in their chemical and isotopic composition. The current study presents 276 (published and unpublished) trace element water data and discusses the sources and processes affecting the water by taking into consideration the framework of their geographic distribution. The dataset is divided in groups using temperature- and pH-related criteria. Results yield a wide range of concentrations, often related to the solubility properties of the individual elements and…
Determination of the mineral composition of foods by infrared spectroscopy: a review of a green alternative.
2014
The determination of mineral composition of foods involves, in most cases, the use of long and tedious sample preparation, which consumes acids and reagents and sometimes requires the use of expensive instrumentation. This is the main reason for the search for direct analytical procedures, based on the use of infrared sample spectra and chemometrics, to model the signals in order to determine the presence of essential and trace toxic elements in foods. The state-of-the-art of the research in this field has been established in the present review article from the critical evaluation of articles available in the literature. Chemometric methods employed and their validation, together with a dis…