- Badajoz, Extremadura, Spain
Eduardo Pinilla-Gil
Universidad de Extremadura, Analytical Chemistry, Faculty Member
- Analytical Chemistry, Chemistry, Water quality, Atmospheric Aerosols, Trace Elements, Environmental Chemistry, and 25 moreEnvironmental Analytical Chemistry, Voltammetry, Stripping voltammetry, Air Quality, Environmental Monitoring, Soil Pollution, Potentiometric Stripping Analysis, Capillary electrophoresis, Quantification and speciation of Arsenic, Screen Printed Electrode, Bismuth Electrode, Urban Dust, Biotechnology, Electrochemical Sensors, Electroanalytical Chemistry, Heavy Metal, Heavy Metal Pollution, Medio Ambiente, Contaminacion Ambiental, Quimica Analitica, Environmental Pollution, Air pollution, Mercury Pollution, Heavy metals, and Wearable sensorsedit
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Abstract On the 5th of May 2008, the first recorded eruption of the Chaiten Volcano in southern Chile occurred. Because one of the main natural sources of Sb is volcanic activity, it was necessary to study the distribution of Sb and its... more
Abstract On the 5th of May 2008, the first recorded eruption of the Chaiten Volcano in southern Chile occurred. Because one of the main natural sources of Sb is volcanic activity, it was necessary to study the distribution of Sb and its species in the nearby ecosystem. The present study aims to develop a methodology for total Sb determination by ICP-MS and a method for Sb(V) and Sb(III) determination by HPLC-HG-AFS in soils, sediments and volcanic ash. Microwave digestion in a 6 mL HNO 3 and 0.5 mL HBF 4 acid digestion mixture can achieve total solubilization of Sb in solid samples. Thirty minutes at 200 °C with 100 mmol L − 1 of oxalic acid were suitable conditions for fast and efficient microwave extraction to obtain a good extraction yield. However, Sb(III) stabilization was strongly inhibited; thus, the mixture of 100 mmol L − 1 + 20 mmol L − 1 of ascorbic acid was the best for Sb solubilization and Sb(III) stabilization. A total of 1.8 ± 0.1 μg g − 1 of Sb was quantified in the volcanic ash from the first eruption. The Sb concentrations in the sediments were 3 times higher than the Sb concentrations in the sediments from the reference zone. In the extracts of the volcanic ash and sediment, Sb(III) was the most abundant species, accounting for 70 to 97% of the total Sb found in the extracts. The results suggest that most of the Sb thrown from the Chaiten Volcano accumulated in the sediments at the mouths of the Yelcho and Chaiten Rivers, mainly in the form of Sb(III).
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We report here the use of commercial screen-printed disposable sensors comprising a sputtered bismuth working electrode, a silver pseudo reference electrode and a carbon auxiliary electrode (whole set referred as BispSPE), as a new and... more
We report here the use of commercial screen-printed disposable sensors comprising a sputtered bismuth working electrode, a silver pseudo reference electrode and a carbon auxiliary electrode (whole set referred as BispSPE), as a new and advantageous alternative for reliable and convenient monitoring of Cd and Pb in atmospheric particulate matter (PM10 fraction) by anodic stripping voltammetry after acid digestion. After a detailed exploration of surface composition and depth profiles of the BispSPE by SEM, EDX, XPS and EIS, chemical and instrumental variables have been optimized to develop a reliable method capable of measuring Cd and Pb with detection limits of 11.8 ng mL−1 and 6.1 ng mL−1 respectively. These detection limits are useful for pollution monitoring of these elements in ambient air under the requirements of international health and environmental protection standards. The accuracy of the method was assessed by voltammetric measurements of Cd and Pb in ERM®-CZ120 Fine dust (PM10-like) and ERM® 1648a Urban Particulate Matter certified reference materials. The applicability of the method to Cd and Pb determination in real samples was demonstrated by analysis of PM10 samples from the air quality network in Extremadura, with a good correlation respect to the standard ICP-MS methodology. Our work constitutes the first reference about the use of disposable sensors based on BispSPE for the determination of heavy metals in atmospheric particulate matter samples.
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With an estimated present global market of US$ 86.3 billion and expected annual increase around 7.9 % from now to 2020, sensors are nowadays one of the most active areas of research and technological developments [1] and a basic... more
With an estimated present global market of US$ 86.3
billion and expected annual increase around 7.9 % from
now to 2020, sensors are nowadays one of the most active
areas of research and technological developments [1]
and a basic pillar of the emerging mobile health strategy
that is expected to be revolutionizing healthcare in the
near future. The biosensor and chemical sensor category
is one of the most growing segment of this market, mainly
due to increased use for medical purposes. Wearable
electrochemical sensors conform a particularly flourishing
category that benefits from the improvements in micro
and nano fabrication of electrodes and instrumental
components based on a range of new electrode materials
(e.g. graphene). They are also expanding thanks to the
widespread availability of advanced signal processing and
management technologies on smartphones, tablets and
similar portable devices. The aim of this contribution is
to highlight the most outstanding recent progresses in
the field of wearable electrochemical sensors for decentralized
bioanalysis and show some examples of research
trends that will shape the sector and expand applicability
fields in the near future.
billion and expected annual increase around 7.9 % from
now to 2020, sensors are nowadays one of the most active
areas of research and technological developments [1]
and a basic pillar of the emerging mobile health strategy
that is expected to be revolutionizing healthcare in the
near future. The biosensor and chemical sensor category
is one of the most growing segment of this market, mainly
due to increased use for medical purposes. Wearable
electrochemical sensors conform a particularly flourishing
category that benefits from the improvements in micro
and nano fabrication of electrodes and instrumental
components based on a range of new electrode materials
(e.g. graphene). They are also expanding thanks to the
widespread availability of advanced signal processing and
management technologies on smartphones, tablets and
similar portable devices. The aim of this contribution is
to highlight the most outstanding recent progresses in
the field of wearable electrochemical sensors for decentralized
bioanalysis and show some examples of research
trends that will shape the sector and expand applicability
fields in the near future.
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The present work investigates soil pollution by elemental contaminants and compares ecological risk indexes related to industrial activities for the case study of Puchuncaví-Ventanas: a relevant industrial zone located in central Chile.... more
The present work investigates soil pollution by elemental contaminants and compares ecological risk indexes related to industrial activities for the case study of Puchuncaví-Ventanas: a relevant industrial zone located in central Chile. Selected elements (As, Pb, Cd, Ni, Hg, V, Mn, Zn, Sr, Sb, Cr, Co, Cu, K, and Ba) were analyzed during a long-term period (yearly sampling campaigns during 2007–2011), at 5 sampling stations representing different degrees of impact. PCA and cluster analysis allowed identifying a copper smelter and a coal-fired power plant complex as major pollution sources. Geoaccumulation index (Igeo), enrichment factor (EF), contamination factor (Cf), contamination degree (Cdeg), and integrated pollution index (IPI) are critically discussed for quantitative ecological risk assessment. Igeo, EF and Cf indexes are producing comparable environmental information, showing moderate to high pollution risks in the area that demands further monitoring and adoption of prevention and remediation measures.
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A combination of probe ultrasonic extraction, optimized by surface response methodology, and Inductively coupled plasma mass spectrometry (ICP-MS) detection is described in this work as an effective methodology for mercury monitoring in... more
A combination of probe ultrasonic extraction, optimized by surface response methodology, and Inductively coupled plasma mass spectrometry (ICP-MS) detection is described in this work as an effective methodology for mercury monitoring in soils affected by industrial emissions. Minute amounts of samples (typically 20 mg) can be extracted in 3 min by 1 mL of HCl-based extracting solution, without risk of mercury losses, and sub sequentially assayed by ICP-MS. The method was successfully tested on soil standard reference materials and then applied to mercury monitoring in a large set of real soil samples collected during a long-term monitoring survey (2007–2011) around the industrial area of Puchuncaví, Chile. The method proved to be useful for investigation of spatial and temporal mercury variability in the area, showing an intermediate to high mercury contamination with potential impact on the surrounding ecosystem.
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This study presents the results of a quality assurance evaluation program applied to the method routinely used for the evaluation of a large elemental profile in aerosol samples from the air quality surveillance network of Extremadura,... more
This study presents the results of a quality assurance evaluation program applied to the method routinely used for the evaluation of a large elemental profile in aerosol samples from the air quality surveillance network of Extremadura, Spain, where low pollution levels are usually encountered. A critical evaluation of the most relevant analytical steps is presented, including long-term blank values evaluation, limits of detection, certified reference material recoveries, method uncertainty and results of comparison studies for gravimetric and trace element analysis. Results obtained at the air quality network of Extremadura for the gravimetric and multielemental analysis are presented for the 2008 campaign.
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A new methodology involving a simple and fast pretreatment of the samples by microwave-assisted extraction and concentration by N2 stream, followed by HPLC with fluorescence detection, was used for determining the concentration of... more
A new methodology involving a simple and fast pretreatment of the samples by microwave-assisted extraction and concentration by N2 stream, followed by HPLC with fluorescence detection, was used for determining the concentration of benzo(a)pyrene (BaP) in atmospheric particulate matter (PM10 fraction). Obtained LOD, 1.0 × 10−3 ng/m3, was adequate for the analysis of benzo(a)pyrene in the samples, and BaP recovery from PAH in Fine Dust (PM10-like) certified reference material was nearly quantitative (86 %). The validated procedure was applied for analyzing 115 PM10 samples collected at different sampling locations in the low-polluted area of Extremadura (Southwest Spain) during a monitoring campaign carried out in 2011–2012. BaP spatial variations and seasonal variability were investigated as well as the influence of meteorological conditions and different air pollutants concentrations. A normalized protocol for health risk assessment was applied to estimate lifetime cancer risk due to BaP inhalation in the sampling areas, finding that around eight inhabitants per million people may develop lung cancer due to the exposition to BaP in atmospheric particulates emitted by the investigated sources.
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We report the first characterisation of screen-printed gold-based electrodes.We monitor the influence of amalgam formation after SW determination of Hg.Structural changes of the surface of the SPEs are studied by EIS.Gold-based... more
We report the first characterisation of screen-printed gold-based electrodes.We monitor the influence of amalgam formation after SW determination of Hg.Structural changes of the surface of the SPEs are studied by EIS.Gold-based screen-printed electrodes have been characterised by electrochemical impedance spectroscopy (EIS) to better understand their behaviour in electroanalytical applications, particularly in the anodic stripping voltammetry of Hg(II). After a first exploration by cyclic voltammetry, impedance spectra of gold-based screen-printed sensors were recorded in 0.1 M HCl electrolyte solution, in the presence of dissolved oxygen and with no electrochemical pre-treatment of the surface. The spectra demonstrated the differences in the interfacial characteristics of each kind of sensor. Structural changes in the surface of SPGEs caused by amalgam formation in the presence of Hg(II) were investigated by EIS. The results obtained were used to elucidate the implications for using the sensor in the stripping voltammetric determination of Hg(II) in environmental samples.
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A simple strategy based on the combination of a high-throughput bath ultrasonic extraction with portable electrochemical determination was developed for fast Hg(II) monitoring in dust samples, with potential applicability to decentralized... more
A simple strategy based on the combination of a high-throughput bath ultrasonic extraction with portable electrochemical determination was developed for fast Hg(II) monitoring in dust samples, with potential applicability to decentralized atmospheric pollution assessment. Square-wave anodic stripping voltammetry (SWASV) on gold nanoparticles-modified screen-printed carbon electrodes (AuNPs-SPCEs) coupled to the extraction procedure resulted in a convenient method for sensitive, reliable, and reproducible mercury detection. The proposed combination of techniques was evaluated with good agreement by using NIST Standard Reference Material 2583 Trace Elements in Indoor Dust. The method was successfully applied for Hg monitoring in complex and heterogeneous indoor dust samples collected at different indoor ambients. ICP-MS was used to contrast the voltammetric measurements.
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The applicability of commercial screen-printed gold electrodes (SPGEs) connected to a portable potentiostat and a laptop has been explored to optimize a new square wave anodic stripping voltammetric method for on-site determination of... more
The applicability of commercial screen-printed gold electrodes (SPGEs) connected to a portable potentiostat and a laptop has been explored to optimize a new square wave anodic stripping voltammetric method for on-site determination of soluble Cu(II) in atmospheric deposition samples taken around an industrial complex. Electrode conditioning procedures, chemical and instrumental variables have been optimized to develop a reliable method capable of measuring dissolved copper with a detection limit of 3.7 ng mL−1, useful for pollution monitoring or screening purposes. The proposed method was tested with the SLRS-5 River Water for Trace Metals (recoveries 109.9–113.1%) and the SPS-SW2 Batch 121 Elements in Surface Waters (recoveries 93.2–97.6%). The method was applied to soluble Cu(II) measurement in liquid samples taken by a total atmospheric deposition collector modified with a quartz filter for soluble and insoluble elemental speciation. The voltammetric measurements on field samples were tested in the lab by a reference ICP-MS method, with good agreement. The proposed method proved capability for field operation during a two weeks monitoring campaign.
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A set of 72 PM10 samples from lowpolluted urban and rural locations belonging to the regional air monitoring network of Extremadura (Spain) were collected in a 1 year sampling period. Sample pre-treatment and analytical determination... more
A set of 72 PM10 samples from lowpolluted
urban and rural locations belonging to the
regional air monitoring network of Extremadura
(Spain) were collected in a 1 year sampling period.
Sample pre-treatment and analytical determination by
gas chromatography–ion trap mass spectrometry were
optimised and validated for the analysis of the priority
16 US Environmental Protection Agency polycyclic
aromatic hydrocarbons (PAHs). The influence of meteorological
conditions (temperature, relative humidity
and solar radiation) and other atmospheric pollutants
(O3, NO2, SO2, PM10) has been covered in detail and
Pearson correlation test were used for this purpose.
Spatial distribution of particulate PAHs was evaluated
and the comparison with other European sites was also
established. Possible emission sources were identified
and assigned by using molecular diagnostic criteria.
urban and rural locations belonging to the
regional air monitoring network of Extremadura
(Spain) were collected in a 1 year sampling period.
Sample pre-treatment and analytical determination by
gas chromatography–ion trap mass spectrometry were
optimised and validated for the analysis of the priority
16 US Environmental Protection Agency polycyclic
aromatic hydrocarbons (PAHs). The influence of meteorological
conditions (temperature, relative humidity
and solar radiation) and other atmospheric pollutants
(O3, NO2, SO2, PM10) has been covered in detail and
Pearson correlation test were used for this purpose.
Spatial distribution of particulate PAHs was evaluated
and the comparison with other European sites was also
established. Possible emission sources were identified
and assigned by using molecular diagnostic criteria.
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A miniaturized, fast, and efficient ultrasonic probe assisted method for Hg(II) extraction from indoor dust samples, in hydrochloric acid medium, was developed. The combination of the extraction method with the electrochemical... more
A miniaturized, fast, and efficient ultrasonic probe assisted method for Hg(II) extraction from indoor dust samples, in hydrochloric acid medium, was developed. The combination of the extraction method with the electrochemical determination of mercury by square-wave anodic stripping voltammetry (SWASV) on gold nanoparticles-modified screen-printed carbon electrodes (AuNPs-SPCEs) resulted in a convenient method for rapid, sensitive, and reliable mercury monitoring. Parameters involved in the extraction such as acid concentration, sonication amplitude, and sonication time were optimized using a Face-centered cube Central Composite Design. ICP-MS was also used to contrast the methodology and good agreement with electrochemical results was verified. Optimization and validation of the procedure were carried out by using NIST Standard Reference Material® 2583 Trace Elements in Indoor Dust. Finally, the proposed methodology was successfully applied for Hg(II) determination in dust samples collected at different indoor ambients.► Optimization of ultrasonic probe microextraction of Hg(II) using chemometric tools. ► Development of SWASV method at AuNPs-SPE for fast and reliable Hg monitoring. ► ICP-MS and Certified Reference Materials for validating the proposed methodology. ► Application to complex dust samples collected at different indoor ambient.
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Seasonal snow precipitation in the Andes mountain range is evaluated as an environmental indicator of the composition of atmospheric emissions in Santiago de Chile metropolitan area, by measuring a set of representative trace elements in... more
Seasonal snow precipitation in the Andes mountain range is evaluated as an environmental indicator of the composition of atmospheric emissions in Santiago de Chile metropolitan area, by measuring a set of representative trace elements in snow samples by ICP-MS. Three late winter sampling campaigns (2003, 2008 and 2009) were conducted in three sampling areas around Cerro Colorado, a Central Andes mountain range sector NE of Santiago (36 km). Nevados de Chillán, a sector in The Andes located about 500 km south from the metropolitan area, was selected as a reference area. The experimental results at Cerro Colorado and Nevados de Chillán were compared with previously published data of fresh snow from remote and urban background sites. High snow concentrations of a range of anthropogenic marker elements were found at Cerro Colorado, probably derived from Santiago urban aerosol transport and deposition combined with the effect of mining and smelting activities in the area, whereas Nevados de Chillán levels roughly correspond to urban background areas. Enhanced concentrations in surface snow respect to deeper samples are discussed. Significant differences found between the 2003, 2008 and 2009 anthropogenic source markers profiles at Cerro Colorado sampling points were correlated with changes in emission sources at the city. The preliminary results obtained in this study, the first of this kind in the southern hemisphere, show promising use of snow precipitation in the Central Andes as a suitable matrix for receptor model studies aimed at identifying and quantifying pollution sources in Santiago de Chile.► Snow precipitation reflects urban atmospheric pollution of Santiago de Chile. ► Snow is enriched with anthropogenic elemental pollutants. ► Results are promising for assignment and tracking of urban pollution sources.
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Plutonium is present in every environmental compartment, due to a variety of nuclear activities. The Southern Hemisphere has received about 20% of the global 239Pu and 240Pu environmental inventory, with an important contribution of the... more
Plutonium is present in every environmental compartment, due to a variety of nuclear activities. The Southern Hemisphere has received about 20% of the global 239Pu and 240Pu environmental inventory, with an important contribution of the so-called tropospheric fallout from both the atmospheric nuclear tests performed in the French Polynesia and in Australia by France and United Kingdom, respectively. In this work we provide new data on the impact of these tests to South America through the study of 239Pu and 240Pu in soils from different areas of Northern, Central and Southern Chile. The obtained results point out to the presence of debris from the French tests in the 20–40° Southern latitude range, with 240Pu/239Pu atomic ratios quite heterogeneous and ranging from 0.02 to 0.23. They are significantly different from the expected one for the global fallout in the Southern Hemisphere for the 30–53°S latitude range (0.185 ± 0.047), but they follow the same trend as the reported values by the Department of Energy of United States for other points with similar latitudes. The 239 + 240Pu activity inventories show as well a wider variability range in that latitude range, in agreement with the expected heterogeneity of the contamination.
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Cd and Pb determination in ambient aerosol samples based on SWASV at a Bi film glassy carbon electrode is described. Extremely acid solutions resulting from sample digestion were directly assayed, with sufficient detection limits for... more
Cd and Pb determination in ambient aerosol samples based on SWASV at a Bi film glassy carbon electrode is described. Extremely acid solutions resulting from sample digestion were directly assayed, with sufficient detection limits for testing the fulfilment of air quality regulations. Accuracy was tested on NIST Standard Reference Materials and real aerosol samples, with good recoveries for Pb comparable to ICP-MS results. Cd was not detected, probably due to the combined effects of low Cd and high interfering Zn and Cu contents. The proposed method provides an attractive alternative to ICP-MS with potential applicability for decentralized analysis.
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A novel electrochemical cell design is proposed to allow fast, reproducible and highly efficient convective transport of dissolved substances to screen-printed electrochemical three-electrode strips mounted on miniaturized plastic... more
A novel electrochemical cell design is proposed to allow fast, reproducible and highly efficient convective transport of dissolved substances to screen-printed electrochemical three-electrode strips mounted on miniaturized plastic vessels, with the goal of improving detection limits in disposable electrochemical stripping field sensors. The experimental configuration has been tested for accumulation of the selected heavy metals ions Zn(II), Cd(II), and Pb(II), codeposited with bismuth ions on a carbon disk screen-printed working electrode before detection by square wave anodic stripping voltammetry. Chemical and instrumental variables of the proposed device and associate electrochemical method were optimized. Selected parameters gave detection limits in the low ng mL−1 range with moderate deposition time (120 s). Practical applicability was tested on certified water and real samples (tap water and waste water), with acceptable results, suggesting potential usefulness for field environmental monitoring of heavy metals.
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Average ranges of particulate matter (PM10 and PM2.5) concentrations and chemical composition in Spain show significant variations across the country, with current PM10 levels at several industrial and traffic hotspots exceeding... more
Average ranges of particulate matter (PM10 and PM2.5) concentrations and chemical composition in Spain show significant variations across the country, with current PM10 levels at several industrial and traffic hotspots exceeding recommended pollution limits. Such variations and exceedances are linked to patterns of anthropogenic and natural PM emissions, climate, and reactivity/stability of particulate species. PM10 and PM2.5 concentrations reach 14–22 μg PM10 m−3 and 8–12 μg PM2.5 m−3 at most rural/regional background sites, 25–30 μg PM10 m−3 and 15–20μg PM2.5 m−3 at suburban sites, 30–46 μg PM10 m−3 and 20–30 μg PM2.5 m−3 at urban background and industrial sites, and 46–50 μg PM10 m−3 and 30–35 μg PM2.5 m−3 at heavy traffic hotpots. Spatial distributions show sulphate and carbon particle levels reach maxima in industrialised areas and large cities (where traffic emissions are higher), and nitrate levels increase from the Atlantic to the Mediterranean (independent of the regional NOx emissions). African dust outbreaks have an influence on the number of exceedances of the daily limit value, but its additional load on the mean annual PM10 levels is only highly significant in Southern Iberia and Canary and Balearic islands. The marine aerosol contribution is near one order of magnitude higher in the Canaries compared to the other regions. Important temporal influences include PM intrusion events from Africa (more abundant in February–March and spring–summer), regional-scale pollution episodes, and weekday versus weekend activity. Higher summer insolation enhances (NH4)2SO4 but depletes particulate NO3− (as a consequence of the thermal instability of ammonium nitrate in summer) and Cl− (due to HCl volatilisation resulting from the interaction of gaseous HNO3 with the marine NaCl), as well as generally increasing dry dust resuspension under a semi-arid climate. Average trace metal concentrations rise with the highest levels at industrial and traffic hotspots sites, in some cases (Ti, Cr, Mn, Cu, Zn, As, Sn, W, and Pb) exceeding rural background levels by over an order of magnitude.
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A study about topsoil antimony distribution and mobility from the soils to the biomass has been afforded in three abandoned Sb mining areas located at Extremadura. Physico-chemical characteristics of the soils and total antimony levels... more
A study about topsoil antimony distribution and mobility from the soils to the biomass has been afforded in three abandoned Sb mining areas located at Extremadura. Physico-chemical characteristics of the soils and total antimony levels were measured in soils and autochthonous plant species (Cytisus striatus, Cistus ladanifer and Dittrichia viscosa). Comparison with corresponding values in reference areas isolated from the mining activities is discussed. Antimony mobility in the soils was estimated by measuring the water extractable fraction; low results were obtained for the three soil areas, with no statistical differences. Plant ability to accumulate antimony was estimated by use of plant accumulation coefficients (PAC). Seasonal (spring vs. autumn) effects on the antimony content in the plant species. Cytisus striatus from Mari Rosa mine presented antimony excluder characteristics, whereas Dittrichia viscosa specimens growing in San Antonio mine showed a significant antimony bioaccumulation.
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The adsorption process of Zn(II) and Cd(II) from aqueous solution has been investigated from both kinetic and equilibrium standpoints, using differential pulse polarography (DPP) on a mercury dropping electrode as the analytical... more
The adsorption process of Zn(II) and Cd(II) from aqueous solution has been investigated from both kinetic and equilibrium standpoints, using differential pulse polarography (DPP) on a mercury dropping electrode as the analytical technique. With such an aim, adsorption experiments were performed using not only a single metal ion–Zn(II) or Cd(II) solution but also a multi-component ion metal–Zn(II), Cd(II) and Hg(II) solution. The influence of the pH change in the multi-component ion metal solution on the adsorption of Zn(II) and Cd(II) was also studied. The adsorption processes is relatively fast for Zn(II) and Cd(II). The presence of two foreign ions in the solution slightly speeds up the adsorption process for Zn(II) and significantly slows it down for Cd(II). The adsorption isotherms are similarly shaped for Zn(II) and Cd(II). The addition of the foreign ions has a more unfavourable effect on the adsorption for Cd(II) than for Zn(II). At pH 2, neither Zn(II) nor Cd(II) is adsorbed practically on the carbon. The voltammetric approach has proved to be a fast and efficient method that, at the same time, enables one to monitor the adsorption of Zn(II) and Cd(II) with potential on-line application, which could be useful in waste-water treatment.
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A potentiometric stripping analysis (PSA) method has been developed and checked for the fast and reliable determination of antimony in vegetation samples of Cistus ladanifer from a mining area in Badajoz, Southwest Spain. The method,... more
A potentiometric stripping analysis (PSA) method has been developed and checked for the fast and reliable determination of antimony in vegetation samples of Cistus ladanifer from a mining area in Badajoz, Southwest Spain. The method, modified from previous PSA methods for Sb in environmental samples, is based on dry ashing of the homogenized leaves, dissolution in hydrochloric acid, and PSA analysis on a mercury film plated on to a glassy carbon disk electrode. The influence of experimental variables such as the deposition potential, the deposition time, the signal stability and the calibration parameters, has been investigated. The method has been compared with an independent technique (instrumental neutron activation analysis) by analysis of standards and reference materials and comparison of the results. As a result of automation of the PSA equipment, the proposed method enables unattended analysis of 20 digested samples in a total time of 2 h, thus providing a useful tool for Sb monitoring of a large number of samples.