Application of Ion Chromatography with ICP-MS or MS Detection to the Determination of Selected Halides and Metal/Metalloids Species

Advances in Portable Heavy Metal Ion Sensors

Heavy metal ions, one of the major pollutants in the environment, exhibit non-degradable and bio-chain accumulation characteristics, seriously damage the environment, and threaten human health. Traditional heavy metal ion detection methods often require complex and expensive instruments, professional operation, tedious sample preparation, high requirements for laboratory conditions, and operator professionalism, and they cannot be widely used in the field for real-time and rapid detection. Therefore, developing portable, highly sensitive, selective, and economical sensors is necessary for the detection of toxic metal ions in the field. This paper presents portable sensing based on optical and electrochemical methods for the in situ detection of trace heavy metal ions. Progress in research on portable sensor devices based on fluorescence, colorimetric, portable surface Raman enhancement, plasmon resonance, and various electrical parameter analysis principles is highlighted, and the characteristics of the detection limits, linear detection ranges, and stability of the various sensing methods are analyzed. Accordingly, this review provides a reference for the design of portable heavy metal ion sensing.

Genome-resolved metagenomics inferred novel insights into the microbial community, metabolic pathways, and biomining potential of Malanjkhand acidic copper mine tailings

Mine tailing sites provide profound opportunities to elucidate the microbial mechanisms involved in ecosystem functioning. In the present study, metagenomic analysis of dumping soil and adjacent pond around India's largest copper mine at Malanjkhand has been done. Taxonomic analysis deciphered the abundance of phyla Proteobacteria, Bacteroidetes, Acidobacteria, and Chloroflexi. Genomic signatures of viruses were predicted in the soil metagenome, whereas Archaea and Eukaryotes were noticed in water samples. Mesophilic chemolithotrophs, such as Acidobacteria bacterium, Chloroflexi bacterium, and Verrucomicrobia bacterium, were predominant in soil, whereas, in the water sample, the abundance of Methylobacterium mesophilicum, Pedobacter sp., and Thaumarchaeota archaeon was determined. The functional potential analysis highlighted the abundance of genes related to sulfur, nitrogen, methane, ferrous oxidation, carbon fixation, and carbohydrate metabolisms. The genes for copper, iron, arsenic, mercury, chromium, tellurium, hydrogen peroxide, and selenium resistance were found to be predominant in the metagenomes. Metagenome-assembled genomes (MAGs) were constructed from the sequencing data, indicating novel microbial species genetically related to the phylum predicted through whole genome metagenomics. Phylogenetic analysis, genome annotations, functional potential, and resistome analysis showed the resemblance of assembled novel MAGs with traditional organisms used in bioremediation and biomining applications. Microorganisms harboring adaptive mechanisms, such as detoxification, hydroxyl radical scavenging, and heavy metal resistance, could be the potent benefactions for their utility as bioleaching agents. The genetic information produced in the present investigation provides a foundation for pursuing and understanding the molecular aspects of bioleaching and bioremediation applications.

Real scenario of metal ion sensor: is conjugated polymer helpful to detect hazardous metal ion

Metal ions from natural and anthropogenic sources cause pollution to society and the environment is major concern in the present scenario. The deposition and contamination of metal ions in soil and water affect the biogeochemical cycles. Thus, it threatens the everyday life of living and non-living organisms. Reviews on the detection of metal ions through several techniques (Analytical methods, electrochemical techniques, and sensors) and materials (Nanoparticles, carbon dots (quantum dots), polymers, chiral molecules, metal-organic framework, carbon nanotubes, etc.) are addressed separately in the present literature. This review reveals the advantages and disadvantages of the techniques and materials for metal ion sensing with crucial factors. Furthermore, it focus on the capability of conjugated polymers (CPs) as metal ion sensors able to detect/sense hazardous metal ions from environmental samples. Six different routes can synthesize this type of CPs to get specific properties and better metal ion detecting capability in vast research areas. The metal ion detection by CP is time-independent, simple, and low cost compared to other materials/techniques. This review outlines recent literature on the conjugated polymer for cation, anion, and dual ion sensors. Over the last half decades published articles on the conjugated polymer are discussed and compared.

Green Aspects of Ion Chromatography versus Other Methods in the Analysis of Common Inorganic Ions

Due to the increasing environmental awareness of the public, green chemistry has become an important element of environmental protection. In laboratories around the world, millions of analyses of inorganic and organic anions and cations in water and wastewater samples, and solid and gaseous samples are performed daily. Unfortunately, these activities still generate large costs, including environmental costs, which are related to the scale of the studies, the use of toxic chemical reagents, the waste generated, and the energy consumed. The methods used so far for inorganic ion analysis, including classical methods, are increasingly being replaced by instrumental methods, primarily based on ion chromatography. This paper presents the most important advantages and limitations of ion chromatography, and compares them with the costs of classical analyses for the analytes and sample types. Both the financial and environmental costs associated with the determination of common inorganic ions, such as Cl−, NO2−, NO3−, and NH4+, in 1000 environmental samples, were compared using selected reference wet classical methods and ion chromatography. The advantages and limitations of ion chromatography that allow this separation technique to be classified as a green analytical chemistry method have been described herein.

The Influence of Sample pH on the Determination of Selected Carboxylic Acids by Isocratic Ion Chromatography

Validated isocratic ion chromatography method with suppressed conductivity detection has been developed for the simultaneously determination of common inorganic anions (F-, Cl-, NO3-, PO43-, SO42-), as well as formate and acetate. Liquid samples originate from absorption of gaseous by-products from coal combustion with and without the addition of medium-density fireboards. The influence of sample pH changes on carboxylic acids determination has been tested.

Iron species determination by high performance liquid chromatography with plasma based optical emission detectors: HPLC-MIP OES and HPLC-ICP OES

The paper presents an independent application of two hyphenated techniques, wherein an identical chromatographic system i.e. high performance liquid chromatography (HPLC) was coupled to microwave induced plasma optical emission spectrometry (MIP OES) or inductively coupled plasma optical emission spectrometry (ICP OES). A cation-exchange column and a mobile phase based on pyridine-2,6-dicarboxylic acid (PDCA) were employed to separate Fe(II) and Fe(III) within 300 s. Additionally, two methods of sample preparation were employed. Optimization and validation of both methods were conducted parallel. The applicability was presented with different sample matrix types: post-glacial sediments, archaeological pottery, soils located in the proximity of industry wastes disposal site, river sediments and yerba mate (Ilex paraguariensis). Obtained results were compared in terms of the excitation source (microwave induced or inductively coupled) and supplied gas (nitrogen or argon). The research introduces HPLC-MIP OES for iron speciation analysis and its applicability were critically evaluated with HPLC-ICP OES.

Determination of ammonium and biogenic amines by ion chromatography. A review

The amount and type of chemical compounds found in food products and the environment, which are and should be controlled, is increasing. This is associated with toxicological knowledge, resulting regulations, rapid development of analytical methods and techniques, and sample preparation methods for analysis. These include, among others, ammonia derivatives such as ammonium, and amines, including biogenic amines. Their occurrence in the environment and food is related to their widespread use in many areas of life and their formation as a result of various physical and chemical changes. Analysts use various methods both classical and instrumental to theirs quantify in different matrices such as food, medicinal and environmental samples. Nevertheless, there is still a need for analytical methods with increased matrix-tolerance, selectivity, specificity, and higher sensitivity. While in the determination of ammonium, ion chromatography is a reference method. In the case of biogenic amines, its use for these purposes is not yet so common. However, given ion chromatography its advantages and rapid development, its importance can be expected to increase in the near future, especially at the expense of gas chromatography methods. This paper is a summary of the advantages and limitations of ion chromatography in this important analytical field and a literature review of the past 15 years.

Ultra-trace determination of oxyhalides in ozonated aquacultural marine waters by direct injection ion chromatography coupled with triple-quadrupole mass spectrometry

A direct, robust, accurate and highly sensitive method for oxyhalide species in natural waters, including seawater, using suppressed ion chromatography coupled with mass spectrometry (IC-MS) is described. The method utilised a high capacity, high efficiency anion-exchange column (Dionex IonPac AS11-HC, 4 mm, 2 × 250 mm), with the separation achieved using an electrolytically generated potassium hydroxide gradient, delivered at 0.380 mL min-1. Applying the method, detection limits for iodate, bromate, and chlorate in seawater after direct sample injection (20 μL injection volume, samples diluted 10-fold), were 11, 30 and 13 ng L-1 (ppt), respectively. Standard addition calibrations to ozonated seawater samples were linear, in all cases R2 > 0.999 (n = 10), with intra-day repeatability of 3.7, 11.2 and 1.8 % RSD (n = 10) for a low-level standard mixture (0.30 μg L-1 of iodate, 0.15 μg L-1 of bromate, and 1.50 μg L-1 of chlorate). The method was applied to the analysis of seawater samples taken pre- and post-disinfection points within a recirculating aquacultural system. Iodate, bromate and chlorate were detected as the main oxyanionic disinfection by-products, demonstrating the practical utility of the new method as a valuable tool for monitoring changes to seawater composition following disinfection treatments.

Multi-mode Sample Introduction System (MSIS) as an interface in the hyphenated system 2 HPLC-MSIS-ICP-OES in simultaneous determination of metals and metalloids species

The paper presents a usage of a new hyphenated technique, wherein a Multi-mode Sample Introduction System (MSIS) was applied as an interface of two high pressure liquid chromatography units and inductively coupled plasma optical emission spectrometry (2 HPLC-MSIS-ICP-OES). Simultaneous separation and detection of non-hydride forming and hydride forming elements was possible due to the application of two different HPLC column, cation-exchange and anion-exchange respectively. The method was able to determine 15 elements quantitatively with a distinction of three arsenic and two iron species and it was validated obtaining acceptable LODs (2.67-28.7 μg L^-1) and recoveries (80-120%). The method applicability was presented and confirmed on 5 varied sample matrix types i.e. post-glacial sediments, yerba mate (Ilex paraguariensis), soil samples located in the proximity of industry wastes disposal site, river sediments, and archaeological pottery. In addition to the above, unknown Cu, Fe, Mn and Zn species were detected in real samples (qualitative speciation analysis) and the identification was attempted according to the literature.

Health risk assessment of selected metals through tap water consumption in Upper Silesia, Poland

The research focused on assessing the risk to human health resulting from the content of selected Cr, Co, Mn, Cu, Ni, Pb, As, Zn and Sr metals in tap water supplied by Upper Silesia Water Plant to the inhabitants of the Upper Silesia region (Poland). It is the main supplier of drinking water to several million inhabitants of this agglomeration. Samples were taken and analyzed quarterly in 2019. The sampling points were chosen to help identify the source when an elevated level of a particular contaminant is observed. ICP-MS and ICP-OES have been used to measure the concentrations of those elements. The chronic daily intake (CDI), hazard quotient (HQ) and hazard index (HI) results for non-carcinogenic risk assessment of metals in tap water has been assessed. CDI values of non-carcinogenic metals were higher in children than in adults; the CDI values for adults and children were found in the order of: Zn > Sr > Cu > Mn > Ni > Pb > Cr > Co > As. All the studied metals had HQ values below 1, the risks caused by the non-carcinogenic metals decreased in the following order: Zn > Cu > Co > As > Sr > Pb > Cr > Ni > Mn. HI values were also less than 1, that meaning that the analyzed tap water is safe for human consumption. The concentration of As, Cr, Cu, Mn and Ni in analyzed tap water is in accordance with Polish and international requirements.

Impact of River Water and Bottom Sediment Pollution on Accumulation of Metal(loid)s and Arsenic Species in the Coastal Plants Stuckenia pectinata L., Galium aparine L., and Urtica dioica L.: A Chemometric and Environmental Study

The role of water and bottom sediment pollution of a river subjected to a strong industrial anthropo-pressure in coastal plants was investigated. The work presented the influence of polluted environment on accumulation of metal(loid)s (including arsenic and its species) in Stuckenia pectinata L., Galium aparine L., and Urtica dioica L. The study provided important information on the contents of organic and inorganic arsenic species in selected plants and their response to heavy metal and arsenic contamination. The As(III), As(V), AB (arsenobetaine), MMA (monomethylarsonic acid), and DMA (dimethylarsinic acid) ions were successfully separated on the Hamilton PRP-X100 column with high-performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) techniques. The Pollution Load Index and geo-accumulation Index (I_geo) values clearly indicate significant pollution of the examined ecosystem with heavy metals. The chemometric analysis with the concepts of (Dis)similarity Analysis, Cluster Analysis, and Principal Component Analysis helped to visualize the variability of the As species concentrations and to analyse correlations between sampling point locations and analyte contents.

Spatial and temporal variability of metal(loid)s concentration as well as simultaneous determination of five arsenic and antimony species using HPLC-ICP-MS technique in the study of water and bottom sediments of the shallow, lowland, dam reservoir in Poland

The optimization of new methodology for simultaneous determination of arsenic [As(III), As(V)] and antimony [Sb(III), Sb(V), SbMe₃] species using high-performance liquid chromatography (HPLC) coupled with inductively coupled plasma mass spectrometry (ICP-MS) in water and bottom sediment samples collected from the dam Kozłowa Góra Reservoir (Poland) was studied. Samples were collected monthly from May to September 2018 in four-point (water) and fifth-point (sediment) transects. The contents of Mn, Co, Ni, Cu, Zn, As, Cr, Rb, Sr, Cd, Sb, Ba, Tl, Pb, and Sb were studied in water and bottom sediments using ICP-MS techniques. Additionally, arsenic and antimony fractions were determined in sediments with the BCR method. Pollution Load Index (PLI), Geoaccumulation Index (I_geo), LAWA classification, and Sb/As ratio indicated the presence of extreme sediment pollution for Zn, Cd, Pb, and Cr from anthropogenic sources. Research has shown that the easy-leached bottom sediment fraction contained in most cases more As(V) and Sb(V). But often Sb(V) concentration was equal as Sb(III), which can be released into the pelagic zone under favorable conditions. Even though As(V) and Sb(V) prevail in the reservoir bottom sediments, they can be transformed into As(III) and Sb(III) as a result of drastic changes in pH or redox potential. The Kozłowa Góra sediments are heavily polluted with Pb, Zn, Cd, and As, Cu, and Ni. The highest concentrations of the heavy metals were recorded in the middle of the tank and there was a small spatial variability. The migration of metals along the reservoir transect was closely related to its morphometry.

Colorimetric detection toward halide ions by a silver nanocluster hydrogel

We reported a novel colorimetric method for highly selective halide ions (Cl^-, Br^-and I^-) recognition by Ag nanoclusters hydrogel (Ag-NCs hydrogel). The Ag-NCs hydrogel could discriminate Cl^-, Br^-and I^- ions from a wide range of environmentally important anions, identified by the distinct UV-vis absorption band changes or the change in the color of Ag-NCs hydrogel. On the basis of this strategy, 20 μM and 200 μM of Cl^-, 5 μM and 100 μM of Br^-, 5 μM and 100 μM of I^- could be recognized within 5 min by UV-vis spectrum and naked eye observation, respectively. The surface color of hydrogel changed from yellow to dark green for Cl^-, to brown for Br^-, and to deep brown for I^-. In addition, this sensing method had been applied successfully to detect chloride anion in real water samples such as tap water, pond water and pure water. Therefore, this rapid, facile, and cost-effective colorimetric assay based on Ag-NCs hydrogel was attractive and promising.

An unprecedented oxidised julolidine-BODIPY conjugate and its application in real-time ratiometric fluorescence sensing of sulfite

Reaction of a julolidine-based BODIPY compound with silver(i) ions in the presence of white light produced the oxidised julolidine version (OXJUL) containing a quaternary nitrogen. The oxidation of one ring at the julolidine site is highly unusual and there is no other reported literature example. The fluorescence maximum of OXJUL is altered from 648 nm to 608 nm by the addition of an aqueous solution of Na2SO3 over several minutes. In the presence of a large excess of sulfite a further slower reaction is observed which further shifts the emission maximum to 544 nm. The alterations form the basis of a real-time ratiometric sensor for sulfite and its detection in a white wine.

Passive sampler measurements of inorganic arsenic species in environmental waters: A comparison between 3-mercapto-silica, ferrihydrite, Metsorb®, zinc ferrite, and zirconium dioxide binding gels

The performances of five Diffusive Gradients in Thin Films (DGT) binding gels, namely 3-mercapto-functionalized silica (3MP), ferrihydrite (Fh), Metsorb^®, zinc ferrite (ZnFe₂O₄)_, and Zirconium oxide (ZrO₂)_, were evaluated for in situ determination of As speciation in water and sediments. A combination of batch experiments at various pH (without addition of buffers) and in the presence of reduced species (Mn²⁺, Fe²⁺ and HS^-),time-series experiments in oxic waters, and in situ deployment in anoxic river sediments has permitted to evaluate the potential interferences among the binding gels. Firstly, the efficiency of each DGT binding gel dedicated to total As (i.e., Fh, Metsorb®, ZnFe₂O₄ and ZrO₂) or As(III) (i.e., 3MP) determination confirms that the determination of As species is possible in oxic freshwater and seawater over 96 h for a wide range of pH (5-9). Secondly, concerning the deployment in river sediment, high HCO₃^- concentrations have a little negative effect only on the DGT performances of the iron(III)-binding gels (i.e, Fh and ZnFe₂O₄). Thirdly, the presence of sulfides does not show any effect on the DGT uptake of As, but strongly affects the elution factor parameter. Discrepancies in elution between the different binding gels potentially result in precipitation of orpiment, especially in 1 mol L^-1 HNO₃. A correction of the classical elution factor derived from batch experiments was applied to provide more representative results. Finally, this study shows the difficulties to determine As speciation in anoxic sediments, and suggests that corrections of the elution factor may be required as a function of the species present in the deployment matrices.

Time and spatial variability in concentrations of selected metals and their species in water and bottom sediments of Dzierżno Duże (Poland)

Poland is an industrialized country in which industries (especially the heavy ones) have had a tremendous influence on the environment. It is particularly visible in the Upper Silesia region, where the observed air, soil and water pollution levels are the most highest. The aim of this study was to determine the time and spatial variability in: concentrations of selected metals (Co, Ni, Zn, Cr, Mn, Pb, Cd), and, to a limited extent, of Cu, V, Al and Sr; concentrations of inorganic ions (Cl^-, SO₄^2-, Na⁺, K⁺, Ca²⁺ and Mg²⁺) and values of pH, conductivity and redox potential. The enlisted parameters were determined for the water and bottom sediments of Dzierżno Duże, a water reservoir located in Poland (Upper Silesia region). Additionally, fractions of a few characteristic metals were determined in the bottom sediments of the discussed reservoir with the BCR method. The investigation was carried out in 2017. It showed that the reservoir surface water was not polluted with the determined metal contents. However, it was highly polluted with the inorganic ions. The metal contents determined in the bottom sediments were high. If the conditions for releasing them from the bottom sediments had been favorable, this situation could have posed a potentially considerable environmental threat.

Development of a fast and efficient analytical technique for the isotopic analysis of fission and actinide elements in environmental matrices

An automated separation-direct analysis scheme has been developed to determine both the concentration and isotopic composition of a suite of elements down to the low picogram level in a complex silicon-based matrix. With the ultimate goal of performing rapid analysis of materials with non-natural isotopic compositions, RAPID (Rapid Analysis of Post-Irradiation Debris) consists of a high-pressure ion chromatography system directly coupled to an inductively coupled plasma mass spectrometer. The RAPID method achieves matrix exclusion and direct online analysis of the elementally separated components, yielding precise isotopic compositions for up to 40 elements in less than one hour per sample. When combined with isotope dilution, this approach shows the potential to yield elemental concentrations with low uncertainties, providing a rapid analytical method that encompasses group I and II metals, transition metals, refractory metals, platinum group metals, lanthanides, and actinides. The method development, robustness, sensitivity, uncertainties, and potential applications in nuclear and environmental measurements will be discussed in this paper.

Time and spatial variability in the concentrations of selected metals in water and bottom sediments of Pławniowice and Dzierżno Małe reservoirs (Poland)

The migration of metals and metalloids between bottom sediments and water and the other way round is a complex process. Understanding those mechanisms is essential for recognizing transformations taking place in water reservoir ecosystems. The objective behind the following study was to define time and spatial correlations in the changes in total concentrations of selected elements (Cr, Zn, Co, Mn, Cu, Ni, Pb, As, Ba, Sb, Sr and V) in waters and bottom sediments from two water reservoirs located in Upper Silesia (Poland), i.e., Pławniowice and Dzierżno Małe. The research was carried out to demonstrate whether the bottom sediments deposited in the discussed reservoirs could pose an environmental threat due to the possible release of toxic metals and metalloids into the pelagic zone. The obtained results constitute material helping to describe the bioavailability of particular elements. They also expose the existing environmental threats for such water reservoirs and their users.

Variability in inorganic As, Sb and Tl species concentrations in waters and bottom sediments of the Kłodnica River (Poland)

The study describes the application of new methodologies for the simultaneous determination of As(III)/As(V), Sb(III)/Sb(V) and Tl(I)/Tl(III) ions in waters and bottom sediments of the Kłodnica River (Poland) with the hyphenated technique of high-performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) . Time and spatial correlations were determined in the changes of total and speciation concentrations of the above-mentioned analytes in Kłodnica river in 2012. The developed methodologies demonstrate high selectivity and limits of quantification at the level of 0.009-0.120 µg/L. Their repeatability, precision and recovery are appropriate for trace analyses of environmental samples. Time and spatial correlations, and concentrations of inorganic As, Sb and Tl ions demonstrated high variability both in water and bottom sediments.

A novel method for determination of inorganic oxyanions by electrospray ionization mass spectrometry using dehydration reactions

Novel methods for the determination of inorganic oxyanions by electrospray (ES) ionization mass spectrometry have been developed using dehydration reactions between oxyanions and carboxylic acids at the ES interface. Twelve oxyanions (VO3 (-) , CrO4 (2-) , MoO4 (2-) , WO4 (2-) , BO3 (3-) , SiO3 (2-) , SiO4 (4-) , AsO4 (4-) , AsO2 (-) , SeO4 (2-) , SeO3 (2-) and NO2 (-) ), out of 16 tested, reacted with at least one of four aminopolycarboxylic acids, i.e. iminodiacetic acid (IDA), nitrilotriacetic acid (NTA), trans-1,2-diaminocyclohexane-N,N,N',N'-tetraacetic acid and triethylenetetramine-N,N,N',N″,N'″,N'″-hexaacetic acid, at the ES interface to produce the dehydration products that gave intense mass ion responses, sufficient for trace analysis. As examples, trace determinations of Cr(VI) and silica in water samples were achieved after online ion exchange chromatography, where the dehydration product of CrO4 (2-) and NTA (m/z 290) and that of SiO4 (4-) and IDA (m/z 192) were measured. The limits of detection of the respective methods were 17 nM (0.83 ng Cr/ml) for Cr(VI) and 0.17 μM (4.8 ng Si/mL) for SiO4 (4-) .

Chemometric and environmental assessment of arsenic, antimony, and chromium speciation form occurrence in a water reservoir subjected to thermal anthropopressure

In the study, arsenic, antimony, and chromium concentrations and selected physicochemical parameters in water and sediment samples from the thermal anthroporessure subjected Rybnik Reservoir (Poland) were determined. As(III), As(V), Sb(III), and Sb(V) ions were successfully separated on Dionex IonPac AS7 column, and Cr(III) and Cr(VI) on Dionex IonPac AG7 column. The obtained limits of detection were 0.18, 0.22, 0.009, 0.012, 0.11, and 0.17 μg/L, respectively. Water and bottom sediment samples were collected monthly at three-point transect between January and November 2013. The As(III) and Sb(III) speciation forms dominated in the bottom water, and Cr(VI) concentration in the bottom water was twice as high as the value measured for the surface water. The oxidized arsenic, antimony, and chromium forms dominated in the bottom sediments in the heated water discharge zone of the Rybnik Power Plant. The location of sampling point had a significant influence on the observed transformations and contents of the analyzed speciation forms. The chemometric analysis coupled with the dissimilarity analysis and principal component analysis helped to visualize the variability in the concentrations of the element speciation forms within the researched period and analyzing correlations.

Determination of total arsenic using a novel Zn-ferrite binding gel for DGT techniques: Application to the redox speciation of arsenic in river sediments

A new laboratory-made Zn-ferrite (ZnFe2O4) binding gel is fully tested using Diffusive Gradient in Thin films (DGT) probes to measure total As [including inorganic As(III) and As(V), as well as MonoMethyl Arsenic Acid (MMAA(V)) and DiMethyl Arsenic Acid (DMAA(V))] in river waters and sediment pore waters. The synthesis of the binding gel is easy, cheap and its insertion into the acrylamide gel is not problematic. An important series of triplicate tests have been carried out to validate the use of the Zn-ferrite binding gel in routine for several environmental matrixes studies, in order to test: (i) the effect of pH on the accumulation efficiency of inorganic As species; (ii) the reproducibility of the results; (iii) the accumulation efficiency of As species; (iv) the effects of the ionic strength and possible competitive anions; and (v) the uptake and the elution efficiency of As species after accumulation in the binding gel. All experimental conditions have been reproduced using two other existing binding gels for comparison: ferrihydrite and Metsorb® HMRP 50. We clearly demonstrate that the Zn-ferrite binding gel is at least as good as the two other binding gels, especially for pH values higher than 8. In addition, by taking into consideration the diffusion rates of As(III) and As(V) in the gel, combining the 3-mercaptopropyl [accumulating only As(III)] with the Zn-ferrite binding gels allows for performing speciation studies. An environmental study along the Marque River finally illustrates the ability of the new binding gel to be used for field studies.

Antimony, Arsenic and Chromium Speciation Studies in Biała Przemsza River (Upper Silesia, Poland) Water by HPLC-ICP-MS

In this paper the total concentration of As, Cr, Sb, pH and the red-ox potential of water and sediment samples of the Biała Przemsza River were determined. The arsenic (AB, MMA, DMA, As(III), As(V)), chromium (Cr(III), Cr(VI)) and antimony (Sb(III), Sb(V)) forms were studied by HPLC-ICP-MS. Ions were successfully separated on Hamilton PRP-X100: (AB, MMA, DMA, As(III), As(V)), Dionex Ion Pac AS-7 (Sb(III), Sb(V)) and Dionex IonPac AG7 columns: Cr(III), Cr(VI) with LOD 0.16 μg/L, 0.08 μg/L, 0.09 μg/L, 0.012 μg/L, 0.08 μg/L, 0.12 μg/L, 0.009 μg/L, 0.012 μg/L, 0.19 μg/L, 0.37 μg/L, respectively. The simplified BCR three-step sequential chemical extraction was performed on the bottom sediment samples. The samples were collected monthly, between April and December 2014, at five sampling points. Large contents of manganese, lead, cadmium and zinc were found in the Biała Przemsza River water. In December 2014, the lead content in the bottom sediment in Sławków was nearly 6000 mg/kg. In the river water, only the inorganic arsenic speciation forms were found. Sb(V), As(V) and Cr(III) were dominant. Studies have shown that arsenic, antimony and chromium were mainly bound to oxides, organic matter and sulphides in the bottom sediments.

Arsenic, Antimony, Chromium, and Thallium Speciation in Water and Sediment Samples with the LC-ICP-MS Technique

Chemical speciation is a very important subject in the environmental protection, toxicology, and chemical analytics due to the fact that toxicity, availability, and reactivity of trace elements depend on the chemical forms in which these elements occur. Research on low analyte levels, particularly in complex matrix samples, requires more and more advanced and sophisticated analytical methods and techniques. The latest trends in this field concern the so-called hyphenated techniques. Arsenic, antimony, chromium, and (underestimated) thallium attract the closest attention of toxicologists and analysts. The properties of those elements depend on the oxidation state in which they occur. The aim of the following paper is to answer the question why the speciation analytics is so important. The paper also provides numerous examples of the hyphenated technique usage (e.g., the LC-ICP-MS application in the speciation analysis of chromium, antimony, arsenic, or thallium in water and bottom sediment samples). An important issue addressed is the preparation of environmental samples for speciation analysis.

Development and validation of HPLC-ICP-MS method for the determination inorganic Cr, As and Sb speciation forms and its application for Pławniowice reservoir (Poland) water and bottom sediments variability study

The optimization of methodology for determination and extraction of inorganic ionic As(III)/As(V), Cr(III)/Cr(VI) and Sb(III)/Sb(V) forms in water and easily-leached fractions of bottom sediments by HPLC-ICP-MS were studied. In paper total concentration of As, Cr, Sb, pH and redox potential were determined. Ions were successfully separated on Dionex IonPac AS7: As(III), As(V), Sb(III), Sb(V) and Dionex IonPac AG7: Cr(III), Cr(VI) with LOD 0.18 μg/L, 0.22 μg/L, 0.009 μg/L, 0.012 μg/L 0.11 μg/L, 0.17 μg/L, respectively. Water and bottom sediments samples were collected monthly from Pławniowice Reservoir, in three-point transects between March and December 2012. In the bottom water predominated As(III) and Cr(III) forms and the highest content of Cr(III) was in the water flowing into the Pławniowice Reservoir. Concentration of Cr(VI) increased in the bottom water in the spring and summer (April-July), while decreasing of the Cr(III) content was associated with the release of Cr(VI) from sediment into the water. Studies have shown that antimony accumulates in reservoir sediments and its reduced form was predominated except May and October-November period when high concentrations of Sb(V) was present. In contrast As(V) was the predominant arsenic form in bottom sediments.