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1.
Ann Chim ; 96(9-10): 601-12, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17172212

RESUMO

The following metals: Al, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn were determined by inductively coupled plasma - atomic emission spectroscopy (ICP-AES) in fluvial sediments of Rosandra Creek, using two different, strong and mild sediment decomposition methods. The purpose was to obtain information about the contamination by metals and distribution paths of pollutants in the area crossed by Rosandra Creek: this little river is the unique epigeous watercourse in the Italian Karst and very few data can be found in literature. In this area, we can find a natural park, but also agricultural activities and an industrial district that was recently defined as "polluted site of national interest". By comparing the results of the strong and mild extraction we have obtained the percentage of extraction and enrichment factors for each metal in the different sediments of the sites R2 and R3 exposed to pollution, while the site R1 was considered as a pristine one because situated in the natural park. The computed enrichment factors are generally not very high, but copper, lead and zinc have factors that require attention. The principal component analysis (PCA) shows that the typically anthropogenic metals (as Cr, Pb, Cu and Zn) constitute the first factor, while the lithogenic metals, as Fe and Ni, constitute the second one; moreover the score plots permit to classify and distinguish the 3 sites: site R3, possibly the more exposed to contamination, has high scores both for anthropogenic and lithogenic metals.


Assuntos
Sedimentos Geológicos/química , Metais/análise , Poluentes Químicos da Água/química , Alumínio/análise , Itália , Metais Pesados/análise , Análise de Componente Principal , Rios , Espectrofotometria Atômica
2.
Ann Chim ; 93(4): 439-46, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12817644

RESUMO

Air quality in Province of Trieste was studied in terms of PM10 trends. Observed correlations between PM10 and atmospheric pollutants produced by combustion are in evidence. Nitrogen oxides and PM10 are critical parameters for air quality in Province of Trieste. Wind speed has a diluting action higher than rain for all pollutants.


Assuntos
Poluentes Atmosféricos/análise , Ar/normas , Ar/análise , Monóxido de Carbono/análise , Indústrias , Itália , Espectrometria de Massas , Óxidos de Nitrogênio/análise , Tamanho da Partícula , Estações do Ano , Dióxido de Enxofre/análise , Saúde da População Urbana
3.
Ann Chim ; 93(1-2): 1-10, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12650568

RESUMO

Cobalt and chromium release in patients undergone a metal-on-metal total hip replacement (THR) is a matter recently discussed and whose we do not have enough information about it yet. In literature there is little data and not completely indicative, in the biological fluids and organs the amounts of released metals are different. This is also due to the fact that cobalt and chromium blood levels can change depending on physical and working activity, individual feeding and metabolism. The results obtained confirm the presence of an increase of cobalt inthe blood of patients after total hip replacement, while the chromium levels are almost alike: average values in patients operated are 4.1 +/- 1.5 microg/L for cobalt (0.3 +/- 0.1 microg/L in the control group) and 4.5 +/- 2.9 microg/L for chromium (4.7 +/- 2.4 microg/L in the control group). In spite of the cobalt values stand below the concentration generally considered dangerous, the difference between the two examined groups points out that a risk exists for the health of these patients. These results must be confirmed by further studies, providing better information and more reliable and biocompatible materials.


Assuntos
Artroplastia de Quadril , Cromo/sangue , Cobalto/sangue , Idoso , Idoso de 80 Anos ou mais , Cromo/farmacocinética , Cobalto/farmacocinética , Feminino , Seguimentos , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco
4.
Environ Monit Assess ; 125(1-3): 291-9, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17219239

RESUMO

Chromium, nickel, copper, zinc and cadmium were determined in sediments of the Niger Delta (Nigeria) in order to discriminate between natural metal sources and anthropogenic ones. Surface sediments were collected at seven sites along a new gas pipeline near Port Harcourt, between the New Calabar River and the Bonny River towards Bonny town. Chemical characterisation is obtained by hydrofluoric-nitric acid digestion procedure, providing the 'total' ('residual') metal contents. Information about the anthropogenic metal fraction was obtained by cold diluted hydrochloric acid extraction procedure. This 'labile' acid soluble fraction of metals, perhaps due to relatively recent inputs in the sediments, constitutes the fraction more likely to be available to marine organisms, and furnishes a first evaluation of the possible toxicity of sediments of this sensitive ecosystem. Zinc appears to be the most available of all the heavy metals: its 'labile' fraction attains 40-50% of the 'total' zinc in sediment. Sites near Port Harcourt city are the most contaminated. All the examined metals are one order of magnitude below the respective values proposed as a limit for toxicity and are comparable with those observed by other authors in similar Niger Delta areas. Some anomalous data found near Port Harcourt city suggest that zinc and cadmium are the metals that require further monitoring. Their anthropogenic source could be derived from urban and industrial sewage.


Assuntos
Poluição Ambiental/prevenção & controle , Sedimentos Geológicos/análise , Metais Pesados/análise , Rios/química , Poluentes Químicos da Água/análise , Nigéria
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