Rare earth elements and relation between their potential bioavailability and soil properties, Nidda catchment (Central Germany)

Rare earth elements (REEs) are widely used in industry and the entry of REEs into the pedosphere is assumed. Data about REEs in soils are scarce since only a few studies discuss their ecologically relevant behavior. Hence, we investigated total contents (aqua regia digestion) and potentially bioavailable contents (EDTA extraction) of REEs in soils from the Nidda catchment in Hesse (Central Germany). The study site covers a 1,600 km² sized area and 232 soil samples from 63 soil profiles were examined. The total REE content varied considerably, ranging from 544 mg kg^?1 to 41 mg kg^?1 (mean 201.1 mg kg^?1) with a high proportion of light REEs. Highest REE contents were found in the soilscape VB, followed by LVB, WNE, T, WSW and BF with the smallest concentrations. With respect to the parent material the contents decreased in the following order: basalt > clay slate > loess > sandstone. On average 15.9% of the total REEs belong to the potentially bioavailable fraction. They range greatly by a factor of 100, between 1.3 and 171.3 mg kg^?1 (average 33.5 mg kg^?1). Remarkably, Yttrium has a maximum available proportion of 75%. In contrast, Ce showed the highest total contents with the smallest potentially bioavailable proportion of all elements. Regression analyses established relation between soil properties and the potential bioavailability of REEs. Around 53% (range from 29.9 to 76.8%) of the REE’s potential bioavailability variations could be explained by the chosen variables (pH, clay and C_org contents and the total element concentrations). Occurrence patterns and concentrations of REEs lie within the range of the results found in the available literature. Bioavailability is linked to soil properties and varies greatly according to the individual element. In comparison with the chosen soil properties the pH value shows the least impact on bioavailability.     

Determination of ochratoxin A in fruit juice by high-performance liquid chromatography after vortex-assisted emulsification microextraction based on solidification of floating organic drop

A rapid, simple, and green vortex-assisted emulsification microextraction method based on solidification of floating organic drop was developed for the extraction and determination of ochratoxin A (OTA) with high-performance liquid chromatography. Some factors influencing the extraction efficiency of OTA such as the type and volume of extraction solvent, sample pH, salt concentration, vortex time, and sample volume were optimized. Under optimized conditions, the calibration curve exhibited linearity in the range of 50.0–500 ng L^?1 with a coefficient of determination higher than 0.999. The limit of detection was 15.0 ng L^?1. The inter- and intra-assays relative standard deviations were in a range of 4.7–8.7%. The accuracy of the developed method was investigated through recovery experiments, and it was successfully used for the quantification of OTA in 40 samples of fruit juice.     

Rare earth elements (REEs) in PM10 and associated health risk from the polymetallic mining region of Nandan County,China

A total of 26 samples were collected from Dachang, Chehe and Liuzhai in Nandan County, China, in order to investigate the concentrations of rare earth elements (REEs) and associated health risk in particulate matter. The concentrations of REEs in Dachang (23.54 ng/m³), Chehe (20.29 ng/m³) were significantly higher than those in Liuzhai (8.1 ng/m³). The light rare earth elements (LREEs) account for 87.08%, 87.09%, and 86.17% of the total REE burden in PM10 at Dachang, Chehe, and Liuzhai, respectively, indicating that the distribution pattern of REEs in PM10 was characterized by the obvious fractionation of LREEs. Enrichment factor calculation indicated that EFs for La, Ce, Nd, Pr, and Nd in PM10 from Dachang and Chehe were greater than 2, indicating moderate enrichment. Source identification indicated that REEs in PM10 from Dacheng and Chehe originated from anthropogenic activities such as mining and smelting activities, while REEs in PM10 from Liuzhai were associated with natural sources, like soil erosion. Noncarcinogenic and carcinogenic risks associated with the exposure of REEs in PM10 were negligible based on the health risk assessment models. However, greater noncarcinogenic risk for children was found in studied areas compared with the adults.     

Trace-Level Determination of Oxolinic Acid and Flumequine in Soil,River Bed Sediment,and River Water Using Microwave-Assisted Extraction and High-Performance Liquid Chromatography with Fluorimetric Detection

This work presents the optimization of analytical procedures for the determination of two antibiotics, oxolinic acid (OA) and flumequine (FL), in bed sediment, river water, and soil samples. Three extraction methods (microwave-assisted extraction (MAE), ultrasonication, and reflux) were tested, and the highest recoveries were obtained with MAE (94 ± 3% and 95 ± 3% for OA and FL, respectively). A solid-phase extraction (SPE) clean-up step was optimized by comparing two polymeric sorbents: Oasis HLB and Oasis MAX. The final extracts were analyzed by liquid chromatography with fluorimetric detection. Limits of detection (LOD) obtained for OA and FL in soil and sediment ranged from 0.3 to 0.5 µg kg^?1. Meanwhile, a novel SPE procedure was also implemented for OA and FL determination in river water samples. It also relied on the use of Oasis MAX, and recovery rates were in the range 90–94%; LODs were 2 ng L^?1 for both OA and FL. These methods were applied for the analysis of samples taken in the Seine River basin (France). The obtained results demonstrated the widespread occurrence of OA and FL, at ng L^?1 and µg kg^?1 levels in water and sediment/soil, respectively, and their persistence in the environment.     

Occurrence and levels of pesticides in South Lebanon water

This study reviews the detection of pesticides in different surface and groundwater samples collected from South Litani region in South Lebanon during 2012. These have been analyzed using an optimized and validated solid phase extraction method followed by gas chromatography coupled with mass spectrometry. Organochlorine and organophosphate pesticides were mostly noted at levels below the recommended value for individual pesticide in water except pirimiphos-methyl that was recorded at 300.87 ng L^?1 in groundwater sample, designated for drinking water and collected in February. DDE concentration exceeded 100 ng L^?1 in both surface and groundwater in October. The reported results represent the first Lebanese statistical data illustrating the quantification of pesticides in water over a period of time. More importantly, it draws attention to the need of pesticides’ monitoring programs in the Lebanese water resources.     

Levels of Metals in Kidney,Liver, and Muscle Tissue and their Influence on the Fitness for the Consumption of Wild Boar from Western Slovakia

Urine lead level is one of the most employed measures of lead exposure and risk. The urine samples used in this study were obtained from ten healthy male cyclists. Dispersive liquid–liquid microextraction combined with ultraviolet and visible spectrophotometry was utilized for preconcentration, extraction, and determination of lead in urine samples. Optimization of the independent variables was carried out based on chemometric methods in three steps. According to the screening and optimization study, 133 μL of CCl₄ (extracting solvent), 1.34 mL ethanol (dispersing solvent), pH 2.0, 0.00 % of salt, and 0.1 % O,O-diethyl dithiophosphoric (chelating agent) were used as the optimum independent variables for microextraction and determination of lead. Under the optimized conditions, R ² was 0.9991, and linearity range was 0.01–100 μg L^?1. Precision was evaluated in terms of repeatability and intermediate precision, with relative standard deviations being <9.1 and <15.3 %, respectively. The accuracy was estimated using urine samples of cyclists as real samples and it was confirmed. The relative error of ≤5 % was considered significant in the method specificity study. The lead concentration mean for the cyclists was 3.79 μg L^?1 in urine samples. As a result, the proposed method is a robust technique to quantify lead concentrations higher than 11.6 ng L^?1 in urine samples.     

Influence of Rare Earth Elements on Metabolism and Related Enzyme Activity and Isozyme Expression in Tetrastigma hemsleyanum Cell Suspension Cultures

The effects of rare earth elements (REEs) not only on cell growth and flavonoid accumulation of Tetrastigma hemsleyanum suspension cells but also on the isoenzyme patterns and activities of related enzymes were studied in this paper. There were no significant differences in enhancement of flavonoid accumulation in T. hemsleyanum suspension cells among La³⁺, Ce³⁺, and Nd³⁺. Whereas their inductive effects on cell proliferation varied greatly. The most significant effects were achieved with 100 μM Ce³⁺and Nd³⁺. Under treatment over a 25-day culture period, the maximal biomass levels reached 1.92- and 1.74-fold and the total flavonoid contents are 1.45- and 1.49-fold, than that of control, respectively. Catalase, phenylalanine ammonia-lyase (PAL), and peroxidase (POD) activity was activated significantly when the REE concentration range from 0 to 300 μM, whereas no significant changes were found in superoxide dismutase activity. Differences of esterase isozymes under REE treatment only laid in expression level, and there were no specific bands. The expression level of some POD isozymes strengthened with increasing concentration of REEs within the range of 50–200 μM. When REE concentration was higher than 300 μM, the expression of some POD isozymes was inhibited; meanwhile, some other new POD isozymes were induced. Our results also showed REEs did not directly influence PAL activity. So, we speculated that 50–200 μM REEs could activate some of antioxidant enzymes, adjust some isozymes expression, trigger the defense responses of T. hemsleyanum suspension cells, and stimulate flavonoid accumulation by inducing PAL activity.     

Distribution of surface soil mercury of Wuda old mining area,Inner Mongolia,China

In this study, mercury (Hg) concentrations in dustfall and topsoil were investigated. Three hundred forty-four samples were collected, including dustfall and topsoil samples, across an area of ～180 km² in Wuda, China. Dustfall Hg concentration in Wuda ranged from 10 to 6453 ng·g^?1_, with an average of 305 ng·g^?1, and topsoil Hg concentration ranged from 3 to 1537 ng·g^?1, with an average value of 135 ng·g^?1. The average dustfall Hg concentrations in the coalfield, industrial park, and urban areas were 289 ng·g^?1, 809 ng·g^?1, and 160 ng·g^?1, respectively, and the corresponding average topsoil Hg concentrations were 216 ng·g^?1, 242 ng·g^?1, and 91 ng·g^?1. Hg concentrations were significantly higher in the coalfield, industrial park, and urban areas compared with background values for Wuda and China tide soil. The coal Hg concentrations ranged from 273 to 346 ng·g^?1, with an average value of 317 ng·g^?1. Comparison of the Hg concentrations of Wuda coal with other regions and countries, indicated that Hg concentrations were significantly enriched in coal, highlighting that coal is the primary Hg source for Wuda District. While coal fires provided the primary source of Hg, some higher Hg values were caused by factors such as gangue hills and coalfield topography, the use of activated carbon with HgCl₂ as a catalyst in the industrial park, and several coal washeries in wasteland areas. In addition to atmospheric Hg, underground coal seam emissions served as another potential Hg source in the coalfield. The surface soil Hg in the coalfield and industrial park areas should be given closer attention in the future.     

Levels of the fungal allergen Asp f 1 in dust from two sawmills in Croatia: a pilot study

Asp f 1 (ribotoxin) is the main allergen of Aspergillus fumigatus and a critical factor in provoking allergic responses and bronchopulmonary aspergillosis. This study investigated the prevalence of allergen Asp f 1 in dust samples collected at two Croatian sawmills from different working sites (sawmilling, parquetry and sorting). A total of thirty-five floor dust samples were collected, extracted, and the mass fraction of Asp f 1 was determined using a commercially available enzyme-linked immunosorbent assay. More than 91 % of the collected dust samples had detectable levels of Asp f 1 (limit detection 3.6 ng g^?1). The median Asp f 1 mass fractions in Sawmill 1 and Sawmill 2 were 49.4 ng g^?1 (range <3.6–120 ng g^?1) and 35.5 ng g^?1 (range 15.1–77.2 ng g^?1), respectively. At both sawmills, higher median Asp f 1 values were found in the dust from sawmilling than from parquetry sites. These preliminary findings suggest the abundance of allergen Asp f 1 in reservoir dust in the woodworking environments of both sawmills. Assessment of Asp f 1 in future studies will provide further insight into the role of this allergen in eliciting respiratory morbidity.     

Recovery and Separation of Rare Earth Elements Using Salmon Milt

Recycling rare earth elements (REEs) used in advanced materials such as Nd magnets is important for the efficient use of REE resources when the supply of several REEs is limited. In this work, the feasibility of using salmon milt for REE recovery and separation was examined, along with the identification of the binding site of REEs in salmon milt. Results showed that (i) salmon milt has a sufficiently high affinity to adsorb REEs and (ii) the adsorption capacity of the milt is 1.04 mEq/g, which is comparable with that of commercial cation exchange resin. Heavier REEs have higher affinity for milt. A comparison of stability constants and adsorption patterns of REEs discussed in the literature suggests that the phosphate is responsible for the adsorption of REE in milt. The results were supported by dysprosium (Dy) and lutetium (Lu) L_III-edge extended x-ray absorption fine structure (EXAFS) spectroscopy. The REE-P shell was identified for the second neighboring atom, which shows the importance of the phosphate site as REE binding sites. The comparison of REE adsorption pattern and EXAFS results between the milt system and other adsorbent systems (cellulose phosphate, Ln-resin, bacteria, and DNA-filter hybrid) revealed that the coordination number of phosphate is correlated with the slope of the REE pattern. The separation column loaded with milt was tested to separate REE for the practical use of salmon milt for the recovery and separation of REE. However, water did not flow through the column possibly because of the hydrophobicity of the milt. Thus, sequential adsorption–desorption approach using a batch-type method was applied for the separation of REE. As an example of the practical applications of REE separation, Nd and Fe(III) were successfully separated from a synthetic solution of Nd magnet waste by a batch-type method using salmon milt.     

Effect of permethrin (pyrethroid insecticide) on the biochemical response of the freshwater amphipod Echinogammarus tacapensis (Chevreux and Gauthier, 1924)

Pyrethroids, the widely used pesticides, are highly toxic to aquatic organisms. However, little information is available on their toxicity on crustaceans. We utilized imagoes of Echinogammarus tacapensis to elucidate the effects of sublethal concentrations of permethrin. The LC50 (48, 72, and 96 h) was assessed considering several pesticide concentrations (ranging between 0.5 and 100 ng L^?1) using the Regtox package and were found to be 13.88, 8.974, and 4.259 ng L^?1, respectively. The biomarkers’ response was analyzed using animals exposed to 0.35, 0.7, and 1.4 ng/L of permethrin for 4 days. The catalase activity was significantly induced after 48 h of exposure to the three permethrin concentrations. Additionally, the glutathione S-transferase activity was increased in a concentration-dependent manner. However, exposed to C1 (0.35 ng L^?1), the superoxide dismutase (SOD) activity showed no significant change compared to control values. The hydrogen peroxide (H₂O₂) rate was found to be similar to the SOD variation. Our findings suggest that permethrin poses a potential threat to freshwater amphipods and thus, the test species can be a useful tool for pesticide toxicity biomonitoring due to their small size, easy husbandry, short life cycle, and high fecundity.     

Use of rare‐earth elements in the phyllosphere colonizer Methylobacterium extorquens PA1

Until recently, rare‐earth elements (REEs) had been thought to be biologically inactive. This view changed with the discovery of the methanol dehydrogenase XoxF that strictly relies on REEs for its activity. Some methylotrophs only contain xoxF, while others, including the model phyllosphere colonizer Methylobacterium extorquens PA1, harbor this gene in addition to mxaFI encoding a Ca²⁺‐dependent enzyme. Here we found that REEs induce the expression of xoxF in M. extorquens PA1, while repressing mxaFI, suggesting that XoxF is the preferred methanol dehydrogenase in the presence of sufficient amounts of REE. Using reporter assays and a suppressor screen, we found that lanthanum (La³⁺) is sensed both in a XoxF‐dependent and independent manner. Furthermore, we investigated the role of REEs during Arabidopsis thaliana colonization. Element analysis of the phyllosphere revealed the presence of several REEs at concentrations up to 10 μg per g dry weight. Complementary proteome analyses of M. extorquens PA1 identified XoxF as a top induced protein in planta and a core set of La³⁺‐regulated proteins under defined artificial media conditions. Among these was a REE‐binding protein that is encoded next to a gene for a TonB‐dependent transporter. The latter was essential for REE‐dependent growth on methanol indicating chelator‐assisted uptake of REEs.     

Solid-phase extraction of tramadol from plasma and urine samples using a novel water-compatible molecularly imprinted polymer

In this study, a novel method is described for the determination of tramadol in biological fluids using molecularly imprinted solid-phase extraction (MISPE) as the sample clean-up technique combined with high-performance liquid chromatography (HPLC). The water-compatible molecularly imprinted polymers (MIPs) were prepared using methacrylic acid as functional monomer, ethylene glycol dimethacrylate as cross-linker, chloroform as porogen and tramadol as template molecule. The novel imprinted polymer was used as a solid-phase extraction (SPE) sorbent for the extraction of tramadol from human plasma and urine. Various parameters affecting the extraction efficiency of the polymer have been evaluated. The optimal conditions for the MIP cartridges were studied. The MIP selectivity was evaluated by checking several substances with similar molecular structures to that of tramadol. The limit of detection (LOD) and limit of quantification (LOQ) for tramadol in urine samples were 1.2 and 3.5 μg L⁻¹, respectively. These limits for tramadol in plasma samples were 3.0 and 8.5 μg L⁻¹, respectively. The recoveries for plasma and urine samples were higher than 91%.     

Impact of Irrigation Strategies on Abscisic Acid and its Catabolites Profiles in Leaves and Berries of Baco noir Grapes

To understand the relationship among soil and plant water status, plant physiology, and the hormonal profiles associated with it, abscisic acid (ABA) and its catabolites [phaseic acid (PA), dihydrophaseic acid (DPA), 7-hydroxy-ABA, 8′-hydroxy-ABA, neophaseic acid, and abscisic acid glucose ester (ABA-GE)] in leaves and berries from wine grape cultivar Baco noir (Folle blanche × Vitis riparia) were analyzed. The experiment was conducted during the growing seasons 2006 and 2007 in an irrigation trial set up in a commercial vineyard located in Niagara-on-the-Lake, ON, Canada. ABA and its metabolites were quantified using liquid chromatography with ion trap combined with electrospray ionization-mass spectrometry. The hormonal profile indicated a direct relationship between the amount of ABA and climatic factors. The ABA varied between 582 and 4,026 ng g^?1 dry matter (DM), DPA between 417 and 562 ng g^?1, and ABA-GE between 337 and 2,764 ng g^?1 DM. At many sampling times PA in the leaves was undetectable, and its highest concentration (260 ng g^?1 DM) was at beginning of July 2007. ABA followed different catabolic pathways depending on the plant water status. ABA was likely catabolized by conjugation to form ABA-GE in treatments at higher water deficit levels, whereas in treatments with high water status, the oxidation pathway leading to DPA or PA was likely preferred. The ABA and ABA-GE concentrations in the berries at harvest showed high correlation with soil and plant water status.     

Pollution assessment of organochlorine pesticides in urban agricultural soils of Jilin City,China

The content, source, and pollution level of organochlorine pesticides (OCPs) in soils are necessary to assess potential risks to eco-environment and human health, and to target environment-friendly policies. A total of 50 surface soil samples were collected from urban vegetable fields of Jilin City and thirteen OCPs were analyzed. The concentrations were in the ranges of 3.16–48.35 ng·g^?1 for Dichloro-Diphenyl-Tricgloroethanes (DDTs, sum of o, p′-DDT, p, p′-DDT, p, p′-DDD, and p, p′-DDE), 4.37–44.77 ng·g^?1 for Hexachlorocyclohexanes (HCHs, sum of α-HCH, β-HCH, γ-HCH, and δ-HCH), 1.19–13.17 ng·g^?1 for Chlordanes (sum of heptachlor, t-chlordane, and c-chlordane), 0.24–2.60 ng·g^?1 for aldrin, and nd–3.43 ng·g^?1 for dieldrin, respectively. The different compositions indicated that the residues of DDTs and HCHs originated mainly from the historical application, while chlordanes were mostly from recent input. On the basis of soil quality standards of China and the Netherlands, DDTs and chlordanes in this study were categorized as light pollution, and HCHs were classified as no pollution for the majority of soil samples. There are a variety of OCPs residues in urban vegetable soils of Jilin City, but it is still safe and suitable for agricultural production.     

The variation of REE (rare earth elements) patterns in soil-grown plants: a new proxy for the source of rare earth elements and silicon in plants

Rare earth elements (REEs) in five species of soil-grown plants (Taxodium japonicum, Populus sieboldii, Sasa nipponica, Thea sinensis and Vicia villosa) and in the soil on which each plant grew were determined with an inductively coupled plasma mass spectrometer (ICP-MS) in order to observe the variation in the distribution of REEs and to elucidate their source in soil-grown plants. The plant samples were divided into root (secondary root and main root), trunk (stem) and leaf; the soils into water soluble (soil_{soluble fraction}), HCl and HNO₃ soluble (soil_{non-silicate fraction}) and HF soluble (soil_{silicate fraction}). The REE abundances of samples were compared using REE patterns where the abundances were normalized to those of a chondrite and plotted on a logarithmic scale against the atomic number. All the plants showed similar REE patterns independent of species and location, and a W-shape variation (W-type tetrad effect) and abundance depletion of cerium (negative Ce anomaly) were found in each REE patterns of plants, more conspicuous tetrad effect being observed in HREE (heavier rare earth elements) region than in LREE (lighter rare earth elements) region. The overall variation of REE patterns of each secondary root was not similar to that of soil_{soluble fraction}, but similar to that of soil_{silicate fraction} except for the tetrad effect and Ce anomaly. The REE patterns can be interpreted by the idea that plants of different species take in REEs and Si from different parts in the soil. The results of this study seem to imply that Sasa nipponica and Vicia villosa take in free REEs and Si rather directly from silicate in the soil, and that a majority of REEs and Si in Taxodium japonicum and Thea sinensis are originated from the soluble fraction in the soil.     

Dimethylsulphopropionate (DMSP) and proline from the surface of the brown alga Fucus vesiculosus inhibit bacterial attachment

It was demonstrated previously that polar and non-polar surface extracts of the brown alga Fucus vesiculosus collected during winter from the Kiel Bight (Germany) inhibited bacterial attachment at natural concentrations. The present study describes the bioassay-guided identification of the active metabolites from the polar fraction. Chromatographic separation on a size-exclusion liquid chromatography column and bioassays identified an active fraction that was further investigated using nuclear magnetic resonance spectroscopy and mass spectrometry. This fraction contained the metabolites dimethylsulphopropionate (DMSP), proline and alanine. DMSP and proline caused the anti-attachment activity. The metabolites were further quantified on the algal surface together with its associated boundary layer. DMSP and proline were detected in the range 0.12–1.08 ng cm^?2 and 0.09–0.59 ng cm^?2, respectively. These metabolites were tested in the concentration range from 0.1 to 1000 ng cm^?2 against the attachment of five bacterial strains isolated from algae and sediment co-occurring with F. vesiculosus. The surface concentrations for 50% inhibition of attachment of these strains were always <0.38 ng cm^?2 for DMSP and in four cases <0.1 ng cm^?2 for proline, while one strain required 1.66 ng cm^?2 of proline for 50% inhibition. Two further bacterial strains that had been directly isolated from F. vesiculosus were also tested, but proved to be the least sensitive. This study shows that DMSP and proline have an ecologically relevant role as surface inhibitors against bacterial attachment on F. vesiculosus.     

In Situ Solvent Formation Microextraction in the Presence of Ionic Liquid for Preconcentration and Speciation of Arsenic in Saline Samples and Total Arsenic in Biological Samples by Electrothermal Atomic Absorption Spectrometry

In this modality, the extraction phase is formed in situ while simultaneously extracting analytes. First, a water-miscible ionic liquid (IL) ([Hmim][BF₄]), capable of complete dissolving in the aqueous solution, was added to the sample. Then, an ion-exchange reagent (NaPF₆) was added to obtain the hydrophobic IL ([Hmim][PF₆]) that acted as the analyte extractant to form the cloudy homogeneous solution for the preconcentration and speciation of trace amounts of As (III) and As (V) with electrothermal atomic absorption spectrometry (ETAAS) detection. In situ solvent formation microextraction is a simple and rapid method for extraction and preconcentration of metal ions from sample solutions containing high concentration of salt. Some effective factors that influence the microextraction efficiency were investigated and optimized. Under the optimum experimental conditions, the limit of detection (3 σ) and the enrichment factor were 6 ng L^-1 and 198, respectively. The obtained relative standard deviation was 4.78%. The proposed method was successfully applied for the determination of As (III) and As (V) in water samples, food salts, and total As in biological samples.     

Amberlite IR-120 Modified with 8-Hydroxyquinoline as Efficient Adsorbent for Solid-Phase Extraction and Flame Atomic Absorption Determination of Trace Amounts of Some Metal Ions

In this study, a solid-phase extraction method combined with atomic absorption spectrometry for extraction, preconcentration, and determination of iron (Fe³⁺), copper (Cu²⁺), and lead (Pb²⁺) ions at trace levels in water samples has been reported. The influences of effective parameters such as flow rate, pH, eluent conditions (type, volume, and concentration), sample volumes, and interference of matrix ions on metal ions recoveries were studied. Under optimized conditions, the limits of detection were found in the range of 0.7–2.2 μg L⁻¹, while preconcentration factors for Fe³⁺, Cu²⁺, and Pb²⁺ ions were found to be 166, 200, and 250, respectively, and loading half time (t _1/2) values were less than 2 min for all analyte ions. The proposed procedure was applied for the determination of metal ions in different water samples with recovery of >94.4% and relative standard deviation less than 4.4% for N = 5.