Search results for "trace elements"

Analysis and assessment of trace element contamination in offshore sediments of the Augusta Bay (SE Sicily): A multivariate statistical approach base…

2014

Abstract An application of multivariate statistical methods is provided to identify anthropogenic contaminants and lithogenic elements in offshore sediments collected near the heavily industrialized Augusta Bay, Sicily. An exploratory statistical technique, based on canonical correlation analysis (CCA) and mixture density estimation approach, is used for distinguishing between natural and anthropogenic contributions of trace elements in the investigated sediments. Following the intensive industrialization of Augusta area, marine sediments reveal the severe impact of local anthropogenic activities for many elements (e.g. As, Cd, Hg, Pb, and Sb), which are considered very dangerous for the en…

Trace elements and PAHs in surface sediments and biota from a contamination hot spot (Augusta Bay, Italy): potential export to the adjoining coastal …

2013

Impact of acidic volcanic emissions on ash leaching and on the bioavailability and mobility of trace metals in soils of Mt Etna

2021

We report on original geochemical data, which combine the rainfall trace metal contents from three different areas of Mt. Etna, variably fumigated by the volcanic plume, and those from soils, collected over the whole volcano. Trace element contents in rainfall appear mostly related to acidic ash leaching, while only for the most volatile elements (Cu, Zn, Cd, Pb, As, Sb, Tl, Se) we suggest a derivation from magmatic degassing. We analyzed separately the labile fraction of soil samples, considered the fraction bioavailable to plants and soil organisms living in. The complexing medium used to extract the bioavailable fraction simulates the growth environment of plant roots.The contents of tra…

Source and Nature of Inhaled Atmospheric Dust from Trace Element Analyses of Human Bronchial Fluids

2011

International audience; Rapid volcanic eruptions quickly ejecting large amounts of dust provoke the accumulation of heavy metals in people living in surrounding areas. Analyses of bronchoalveolar lavage samples (BAL) collected from people exposed to the paroxysmal 2001 Etna eruption revealed a strong enrichment of many toxic heavy metals. Comparing the BAL to the dust composition of southeastern Sicily, we found that only V, Cr, Mn, Fe, Co, and U enrichment could be related to the volcanic event, whereas Ni, Cu, Cd, and Pb contents come from the dissolution of particles of anthropogenic origin. Furthermore, the nature of these inhaled anthropogenic particles was revealed by anomalous La and…

Has long-term metal exposure induced changes in life history traits and genetic diversity of the enchytraeid worm Cognettia sphagnetorum (Vejd.)?

2004

We studied whether long-term metal exposure has affected life history traits, population growth patterns and genetic diversity of the asexual enchytraeid worm Cognettia sphagnetorum (Vejd.). Enchytraeids from metal contaminated and uncontaminated forest soil were compared by growing them individually in the laboratory and by following their population development in patchily Cu contaminated microcosms. Genetic differences between the two native populations were studied using allozyme electrophoresis. Individuals from the contaminated site had slower growth rate and they produced fewer fragments of larger size when compared to individuals from the uncontaminated site. In patchily Cu contamin…

Oral intake of cadmium, cobalt, copper, iron, lead, nickel, manganese and zinc in the university student's diet.

1993

A duplicate diet meal study was carried out with a group of university students living in a hostel, in order to estimate the intake of Zn, Cd, Co, Cu, Fe, Mn, Ni and Pb. Zn, Cu, Fe, Mn and Ni were determined by flame atomic absorption spectrophotometry and Cd, Co and Pb by graphite furnace atomic absorption spectrophotometry after a nitric acid wet digestion procedure. The estimated intake values from the contents of breakfast, lunch, dinner and drinks were compared with the values of the Provisional Tolerable Daily Intake (PTDI) in the case of Cd and Pb, Recommended Dietary Allowances (RDA) of Co, Fe and Zn and Estimated Safe and Adequate Dietetic Daily Intake (ESADDI) of Cu and Mn. Neithe…

Metals in Scalp Hair from Relapsing-Remitting Multiple Sclerosis Patients (RRMS)

2014

We measured the concentrations of 21 chemical elements (TE) in hair of 48 Sicilian patients with RRMS compared with 51 controls (HC). MS patients showed a significantly (p<0.01) lower hair concentration of Al and Rb and higher hair concentration of U compared to HC. The percentage of MS patients showing hair elemental concentrations greater than the 95th percentile of controls was 20% for Ni, 19% for Ba and U, and 15% for Ag, Mo and Se. The ratio Zn/Cu varied from 17 to 19, with no significant differences between HC and MS groups or between individuals differentiated by gender. No significant association was found between levels of each TE and age, disease duration, Expanded Disability Stat…

Trace elemental composition of PM2.5 atmospheric aereosol in Palermo urban area

2009

Trace element behavior in the fluidized bed gasification of solid recovered fuels

2013

Gasification of biomass and recycled fuels is of particular interest for the efficient production of power and heat. Trace elements present as impurities in the product gas should be removed very efficiently. The objective of this work has been to develop and test thermodynamic models for the reactions of trace elements with chlorine and sulfur in the gasification processes of recycled fuels. In particular, the chemical reactions of trace elements with main thermochemical conversion products, main ash components, and bed and sorbent material are implemented into the model. The possibilities of gas cleaning devices in condensing and removing the trace element compounds are studied by establi…

Tracking trace elements from soil to Lebanese bread and Populations Exposure

2021

In Lebanon, the agri-food industry represents 18% of the industrial sector and yet food safety remains a major problem. In this interdisciplinary thesis, we followed the Trace Elements (TEs) in the Lebanese white bread sector "from farm to fork" based on the reality on the ground, and on two links in the sector: (i) the geogenic or anthropogenic origin of TEs present in the soil and their transfer to the wheat grain, for which 10 plots cultivated in wheat, covering the diversity of soils, irrigation practices and anthropogenic environments of the central Bekaa were chosen ; (ii) the exposure of populations to TEs present in bread, for which a survey of consumption habits across Lebanon was …