Total and fractionation metal contents obtained with sequential extraction procedures in a sediment core from Terra Nova Bay, West Antarctica

2012 ◽  
Vol 25 (1) ◽  
pp. 83-98 ◽  
Author(s):  
Claudia E. Casalino ◽  
Mery Malandrino ◽  
Agnese Giacomino ◽  
Ornella Abollino

AbstractA suite of 21 elements, namely Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, La, Mg, Mn, Na, Ni, P, Pb, Sr, Ti, V and Zn, was investigated in a sediment core from the Ross Sea, Antarctica. The experimental results were treated by chemometric techniques. The elemental composition of core H2 was found to be mainly dominated by terrigenous elements, but it is also influenced by biological factors, such as the presence of corals. No evidence of anthropogenic contamination was observed, even in the top layer of the sediment. Furthermore, the modified Community Bureau of Reference (BCR) three-step sequential extraction procedure was applied to evaluate metal mobility and availability. The results confirmed the separation between higher and lower sections of the core and showed the presence of Fe as amorphous and crystalline oxide and of Mn mostly as nodules. The high percentages of metals extracted into the fourth fraction indicate their strong binding with the sediment matrix. Finally, BCR procedure was compared to Tessier's protocol which made it possible to distinguish between mobile and mobilizable fraction. Therefore, in general partitioning procedure must be chosen taking into account the nature of the sample and the aim of the research.

2005 ◽  
Vol 69 (5) ◽  
pp. 591-600 ◽  
Author(s):  
D. A. Rubinos ◽  
M. Arias ◽  
F. Díaz-Fierros ◽  
M. T. Barral

AbstractThe distribution of sorbed arsenic(V) among different geochemical fractions for arsenic(V)-loaded red mud, an oxide-rich residue from bauxite refining that has been proposed as an adsorbent for arsenic, was studied as a function of sorbed arsenic(V) concentration using a sequential extraction procedure. The release of previously sorbed arsenic(V) was also studied as a function of pH and arsenic(V) concentration. Most sorbed arsenic(V) (0.39–7.86 mmol kg–1) was associated with amorphous and crystalline Al and Fe oxides (24.1–43.8% and 24.7–59.0% of total sorbed arsenic, respectively). Exchangeable arsenic was the smallest fraction (0.4–5.2% of total sorbed arsenic). The distribution of sorbed arsenic(V) was related to the arsenic surface coverage. For arsenic surface coverages >∼30% the percentage of arsenic(V) associated with the amorphous Al oxide fraction increased and that associated with the crystalline oxide fraction decreased. The arsenic(V) exchangeable fraction increased from 1.4 to 756 μmol kg–1 as surface coverage increased from 388 to 7855 μmol kg–1. The release of sorbed arsenic(V) from red mud was greater at alkaline pH values (maximum release of ∼33% of previously sorbed arsenic at pH = 12), but for high arsenic(V) initial concentration (0.2 mM arsenic) considerable amounts of arsenic (6.5% of previously sorbed arsenic) were released at pH 4, in accordance with the dissolution of amorphous Al oxides in the red mud. The results obtained suggest a greater mobility of sorbed arsenic(V) as its surface concentration approaches saturation.


2021 ◽  
Vol 13 (12) ◽  
pp. 6532
Author(s):  
Hang Zhao ◽  
Yang Tian ◽  
Rong Wang ◽  
Rui Wang ◽  
Xiangfei Zeng ◽  
...  

Metal mobility and toxicity of the municipal solid waste incineration (MSWI) fly ash from different seasons in Beijing were studied using leaching toxicity procedures, sequential extraction procedures, and bioavailability procedures. The X-ray diffraction results showed that MSWI fly ash contained CaSO4, CaCO3, and KCl. The Pb, Zn, and Cd contents of MSWI fly ash were high, especially during autumn, being 42, 77, and 1260 times higher than that of their soil backgrounds, respectively. Leaching toxicity experiments showed that MSWI fly ash is hazardous, since Pb exceeded the maximum threshold (5 mg/L). The main alkali metal ions and anions, heavy metals total content, leaching concentration, chemical speciation, and bioavailability varied seasonally. The Pb and Zn leaching concentrations in summer and autumn were higher than that of the other two seasons. Sequential extraction procedures indicated that Pb, Zn, and Cd showed extremely high metal mobility, i.e., the residual states of Pb and Cd in spring were 5.83% and 1.21%, respectively, and that of Zn in autumn was 10.68%. These results will help industries, governments, and the public better understand the risk of MSWI fly ash and will urge them to pay more attention to preventing harm to the ecosystem and human beings.


Atmosphere ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 1030
Author(s):  
Flavio Vagnoni ◽  
Silvia Illuminati ◽  
Anna Annibaldi ◽  
Francesco Memmola ◽  
Giada Giglione ◽  
...  

Atmospheric aerosol samples were collected at Faraglione Camp, 3 km away from the Italian Mario Zucchelli Station (Terra Nova Bay, Ross Sea), from 1 December 2013 to 2 February 2014. A two-step extraction procedure was applied to characterize the soluble and insoluble components of PM10-bound metals. Samples were analyzed for Al, Fe, Cd, Cu, and Pb by square wave anodic stripping voltammetry (SWASV) and by graphite furnace atomic absorption spectrophotometer (GF-AAS). The mean atmospheric concentrations were (reported as means ± SD) Al 24 ± 3 ng m−3; Fe 23 ± 4 ng m−3; Cd 0.92 ± 0.53 pg m−3; Cu 43 ± 9 pg m−3, and Pb 16 ± 5 pg m−3. The fractionation pattern was metal-specific, with Al, Fe, and Pb mainly present in the insoluble fractions, Cd in the soluble one, and Cu equally distributed between the two fractions. The summer evolution showed overall constant behavior of both fractions for Al and Fe, while a bell-shaped trend was observed for the three trace metals. Cd and Cu showed a bell-shaped evolution involving both fractions. A seasonal increase in Pb occurred only for the insoluble fraction, while the soluble fraction remained almost constant. Sequential extraction and enrichment factors indicated a crustal origin for Al, Fe, and Pb, and additional (marine or anthropogenic) contributions for Cd and Cu. Back trajectory analysis showed a strong contribution of air masses derived from the Antarctic plateau. A potential low contribution from anthropized areas cannot be excluded. Further studies are necessary to better characterize the chemical composition of the aerosol, to discriminate between natural and anthropogenic sources, and to evaluate a quantitative source apportionment.


Soil Research ◽  
2006 ◽  
Vol 44 (2) ◽  
pp. 135 ◽  
Author(s):  
G. L. Guo ◽  
Q. X. Zhou ◽  
P. V. Koval ◽  
G. A. Belogolova

Knowledge of the total content of trace metals is not enough to fully assess the environmental impact of polluted soils. For this reason, the determination of metal speciation in soil is important to evaluate its mobilisation capacity and behaviour in the environment. The sequential extraction procedure was used to separate 4 heavy metals (Cd, Pb, Cu, Zn) from contaminated Phaeozem in north-east China into 5 operationally defined geochemical species: exchangeable, bound to carbonates, bound to Fe–Mn oxides, bound to organic matter, and residues. Neutral salts, dilute acids, and chelating reagents were used as single extractants for the functionally defined speciation. In the sequential extraction, the residual fraction was the most abundant pool for Pb, Cu, and Zn. A major portion (40–84%) of Pb, Cu, and Zn was associated with the residue. The speciation distribution of Pb, Cu, and Zn in the surface samples was similar to that in the subsurface, with residues > bound to organic matter > bound to Fe–Mn oxides > bound to carbonates > exchangeable. A significant amount (32–47%) of Cd persisted in the potential availability of the exchangeable fraction. The main part of Cd fractionation in the surface soil samples comprised exchangeable, carbonate, and Fe–Mn oxide fractions, whereas in the subsurface it comprised the residual and exchangeable phases. EDTA can be regarded as an extractant for assessing the plant-available species of Cd, Cu, and Zn; NH4Cl released electrostatically weakly bound metals and was used to estimate the mobile species. Assuming that metal mobility and bioavailability are related to their solubility and the contents in typical plants in the contaminated Phaeozem, Cd would be the main potential risk to animal health and groundwater safety in the area.


1995 ◽  
Vol 32 (1) ◽  
pp. 57-62 ◽  
Author(s):  
Valérie Colandini ◽  
Michel Legret ◽  
Yves Brosseaud ◽  
Jean-Daniel Baladès

Porous pavements infiltrated with stormwater are faced with clogging problems: runoff particles seep and clog the pervious surface layer of these structures. Clogging material samples (in the form of sludge) have been collected in cleaning operations on the pervious asphalt. This study aims at characterizing these materials, particle size distribution, heavy metal contents by particle size, and studying interactions between metals and particles. A sequential extraction procedure proposed by the experts of the Community Bureau of Reference (B.C.R.) was applied to provide information about heavy metal distribution on particles and to evaluate interaction strength, and consequently potential metal mobility when chemical variations occurred in the environment. Mainly made up of sand, the materials are polluted with lead, copper, zinc and cadmium. The concentrations appeared to be linked with road traffic intensity. The heavy metal contents by particle size showed that the finer are the particles, the higher are the heavy metal concentrations. Heavy metals were found potentially labile; metals contents in the residual fraction (mineral fraction) represented less than 20 % of the total concentration. Cadmium and zinc were apparently more labile than lead and copper.


MethodsX ◽  
2020 ◽  
Vol 7 ◽  
pp. 100888
Author(s):  
Margit H. Simon ◽  
Daniel P. Babin ◽  
Steven L. Goldstein ◽  
Merry Yue Cai ◽  
Tanzhuo Liu ◽  
...  

2021 ◽  
pp. 103510
Author(s):  
Alessandro Cau ◽  
Claudia Ennas ◽  
Davide Moccia ◽  
Olga Mangoni ◽  
Francesco Bolinesi ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document