Search results for "metalloids"
showing 10 items of 13 documents
Stability of biogenic metal(loid) nanomaterials related to the colloidal stabilization theory of chemical nanostructures
2018
In the last 15 years, the exploitation of biological systems (i.e. plants, bacteria, mycelial fungi, yeasts, and algae) to produce metal(loid) (Me)-based nanomaterials has been evaluated as eco-friendly and a cost-effective alternative to the chemical synthesis processes. Although the biological mechanisms of biogenic Me-nanomaterial (Bio-Me-nanomaterials) production are not yet completely elucidated, a key advantage of such bio-nanostructures over those chemically synthesized is related to their natural thermodynamic stability, with several studies ascribed to the presence of an organic layer surrounding these Bio-Me-nanostructures. Different macromolecules (e.g. proteins, peptides, lipids…
Dust, Metals and Metalloids in the Environment: From Air to Hair .
2013
Billions tons of particulate matter, made up of inorganic and organic compounds, are released every year into the atmosphere, from both anthropogenic and natural sources. The latter, which include geogenic material from erosion, agriculture, sea spray and volcanic activity, account for about 97% of the total mass of particles. The contribution of anthropogenic sources, about 3%, is more pronounced in industrialised and also in urban areas, where vehicular traffic is one of the most important sources. When examining the health impact, in addition to mass level and size, two other main characteristics of particulate matter need to be considered: its nature and chemical composition. These para…
Sorption of V and VI group metalloids (As, Sb, Te) on modified peat sorbents
2016
AbstractThe present work investigates arsenic, antimony and tellurium sorption using iron modified peat. The results were obtained using batch tests and the sorption was studied as a function of initial metalloid concentration, pH and sorption time, as well as the presence of competing substances. The obtained results indicate that modification of peat with Fe compounds significantly enhances the sorption capacity of the sorbents used for sorption of arsenic, antimony and tellurium. The optimal pH interval for the sorption of Sb(III) is 6.5–9 and for As(V) and Sb(V) – 3–6, while As(III) and tellurium sorption using Fe-modified peat is favourable in a wider interval of 3–9. The presence of c…
Gender as a key factor in trace metal and metalloid content of human scalp hair. A multi-site study
2016
This multi-site study discusses the content of metals and metalloids (MM) in scalp hair of children, living in different environmental contexts, with the purpose of verifying if hair level of some MM is distinctively gender-specific. A total of 943 hair samples (537 females and 406 males) from adolescents were analysed for their content of Al, As, Ba, Cd, Co, Cr, Cu, Li, Mn, Mo, Ni, Pb, Rb, Sb, Se, Sr, U, V and Zn. Elemental quantification was performed by ICP-MS. The obtained data identified different metal distributions in adolescent girls which exhibited significantly higher hair concentrations of some trace metals, especially Sr, Zn and Ni, than boys. On the base of the median value, hai…
Exposure to metals and metalloids among pregnant women from Spain: Levels and associated factors
2021
This study was funded by Grants from EU (FP7-ENV-2011 cod 282957 and HEALTH.2010.2.4.5-1); Spain: ISCIII (Red INMA G03/176, CB06/02/0041; FIS-FEDER: PI03/1615, PI04/1509, PI04/1112, PI04/1931, PI05/1079, PI05/1052, PI06/0867, PI06/1213, PI07/0314, PI09/00090, PI09/02647, PI11/01007, PI11/02591, PI11/02038, PI13/1944, PI13/2032, PI13/02187, PI14/00891, PI14/01687, PI16/1288, PI17/00663, PI18/01142 and PI19/1338; Miguel Servet FEDER MS15/00025, MS20/0006, CPII16/00051, and FIS-FSE: 17/00260); CIBERESP; Generalitat Valenciana: FISABIO (UGP 15-230, UGP-15-244, and UGP-15-249), AICO/2020/285, and Alicia Koplowitz Foundation 2017; Generalitat de Catalunya-CIRIT 1999SGR 00241; Department of Health…
V un VI grupas metaloīdu sorbcijas izpēte uz modificētiem biomateriālu sorbentiem
2015
Promocijas darbā veikta augstas pievienotās vērtības sorbentu izstrāde, izmantojot vienu no Latvijas nozīmīgākajiem vietējiem derīgajiem izrakteņiem, un pētītas to izmantošanas iespējas. Promocijas darbā sintezēti sorbenti, kuru pamatā ir biomateriāli, kas modificēti ar dzelzs savienojumiem. Izvērtētas kūdras kā sorbenta izmantošanas iespējas, kā arī pētītas kūdras modificēšanas metodes un to ietekme uz sorbcijas kapacitāti. Bez kūdras izmantoti arī tādi materiāli kā sūnas, skaidas, salmi, niedres, humīnskābes un salīdzinājumam arī smiltis, kas arī modificēti ar dzelzs savienojumiem. Sintezētie sorbenti raksturoti, izmantojot skenējošo elektronmikroskopiju (SEM), Furjē tanformācijas infrasa…
An uptake and elimination kinetics approach to assess the bioavailability of chromium, copper, and arsenic to earthworms (Eisenia andrei) in contamin…
2019
The aim of this study was to determine the bioavailability of metals in field soils contaminated with chromated copper arsenate (CCA) mixtures. The uptake and elimination kinetics of chromium, copper, and arsenic were assessed in the earthworm Eisenia andrei exposed to soils from a gradient of CCA wood preservative contamination near Hartola, Finland. In soils contaminated with 1480–1590 mg Cr/kg dry soil, 642–791 mg Cu/kg dry soil, and 850–2810 mg Ag/kg dry soil, uptake and elimination kinetics patterns were similar for Cr and Cu. Both metals were rapidly taken up and rapidly excreted by Eisenia andrei with equilibrium reached within 1 day. The metalloid As, however, showed very slow uptak…
Levels of trace elements in human hair samples of adolescents living near petrochemical plants
2020
The aim of the study is a comparative analysis to investigate human hair metal profiles of adolescents residing near petrochemical plants (Sicily, Italy). We selected the small town of Augusta, Gela, and Pace del Mela, and a control area made up of the towns characterized by low anthropogenic activity. Twenty trace elements were measured in samples of scalp hair from adolescents (11–14 years old) of both genders. Hair samples were cleaned using a rigorous cleaning method, mineralized, and processed for analyses by inductively coupled plasma–mass spectrometry (ICP-MS). In industrial sites, zinc was always the most abundant element, ranging from186 to 217 μg g−1. Following zinc, the elements …
Penalized linear discriminant analysis and Discrete AdaBoost to distinguish human hair metal profiles: The case of adolescents residing near Mt. Etna
2016
The research focus of the present paper was twofold. First, we tried to document that human intake of trace elements is influenced by geological factors of the place of residence. Second, we showed that the elemental composition of human hair is a useful screening tool for assessing people's exposure to potentially toxic substances. For this purpose, we used samples of human hair from adolescents and applied two robust statistical approaches. Samples from two distinct geological and environmental sites were collected: the first one was characterized by the presence of the active volcano Mt. Etna (ETNA group) and the second one lithologically made up of sedimentary rocks (SIC group). Chemica…
Metals and metalloids in hair samples of children living near the abandoned mine sites of Sulcis-Inglesiente (Sardinia, Italy)
2014
International audience; The Sulcis-Iglesiente district (SW Sardinia, Italy) is one of the oldest and most important polymetallic mining areas in Italy. Large outcrops of sulfide and oxide ores, as well as the products of the long-lasting mining activity, are present throughout the district releasing significant quantities of metals and metalloids into the surrounding environment. Here are reported concentrations of 21 elements determined in scalp hair samples from children (aged 11-13 years) living in different geochemical environments of southwestern Sardinia: Iglesias, hosting several abandoned mines, and the island of Sant׳Antioco, not affected by significant base metal mineralization ev…