Evaluation of the Fate of Aldicarb and Its Metabolites in Oranges

Abstract

The accumulation, persistence and fate of systemic pesticide aldicarb was melencholy evaluated in orange crops. The concentration of this pesticide and its two toxic metabolites, aldicarb sulfoxide and aldicarb sulfone was determined in leaves, rind and pulp of three orange varieties (Satsuma, Navelina and Clemetina de Nules) and in the top soil of the orange groves. The groves were located in two different places in the Valencia Community (Spain). The analysis showed that the aldicarb concentration was lower than those of aldicarb sulfoxide and aldicarb sulfone. In all cases, the residues persisted at least 160 days in vegetable samples and between 157 and 227 days in soil samples. Residue concentrations measured in the soil samples were highly variable but a relation with the organic matter content can be observed. The residue levels found in vegetal products were higher in leaves than in rind, and in rind than in pulp. The maximum residue values were obtained between 47 and 70 days after the application. One hundred days after treatment (Security period) the residue levels of total fruit were lower than the maximum residue level of 0.2 mg/kg established by law.     

用吡啶衍生物和Amberlite XAD—4大孔树脂分离富集矿石中微量金

在盐酸或稀王水介质中金与α-氨基吡啶或α-氨基-4-甲基吡啶、2,4-二甲基吡啶等形成的络合物能定量地吸附在Amberlite XAD-4大孔树脂柱上,吸附的金用丙酮-0.1mol/L盐酸(10:1)混合液洗脱,然后用结晶紫光度法测定。除铊(Ⅲ)外,许多贱金属和贵金属离子不吸附,吸附的铊可在洗脱金之前用EDTA溶液洗涤除去。方法具有选择性高、速度快、简便以及柱可长期使用等优点,可应用于矿石中微量金的测定。     

Amberlite XAD-2 functionalized with 2-aminothiophenol as a new sorbent for on-line preconcentration of cadmium and copper

A new functionalized resin has been applied in an on-line preconcentration system for copper and cadmium determination. Amberlite XAD-2 was functionalized by coupling it to 2-aminothiophenol (AT-XAD) by means of an NN spacer. This resin was packed in a minicolumn and used as sorbent in the on-line system. Metal ions were sorbed in the minicolumn, from which it could be eluted directly to the nebulizer-burner system of the flame atomic absorption spectrometer (FAAS). Elution of Cd(II) and Cu(II) from minicolumn can be made with 0.50 mol l⁻¹ HCl or HNO₃. The enrichment factors obtained were 28 (Cd) and 14 (Cu), for 60 s preconcentration time, and 74 (Cd) and 35 (Cu), if used 180 s preconcentration time. The proposed procedure allowed the determination of cadmium and copper with detection limits of 0.14 and 0.54 μg l⁻¹, respectively, when used preconcentration periods of 180 s. The effects of foreign ions on the adsorption of these metal ions are reported. The validation of the procedure was carried out by analysis of certified reference material. This procedure was applied to cadmium and copper determination in natural, drink and tap water samples.     

Determination of Gold and Palladium in Manganese and Nickel Compounds by Atomic Absorption Spectrometry After Separation by Use of Amberlite XAD-7 Resin

Abstract

A method for preconcentration and determination of traces of Au and Pd from manganese, nickel and their compounds is described. The trace elements are preconcentrated at a small column filled with Amberlite XAD-7 resin. After their eluation the elements are determined by flame AAS. The relative standard deviations (N=10) were found to be lower than 5%; the detection limit (3s, N=20) for Au and Pd in metal samples is 0.07 μg/g.     

Synthesis of amberlite XAD-2-PC resin for preconcentration and determination of trace elements in food samples by flame atomic absorption spectrometry

A new chelating sorbent has been developed using Amberlite XAD-2 resin anchored with pyrocatechol through –N=C– group. This sorbent, characterised by elemental analysis and infrared (IR) spectra, was used as packing for the minicolumn in an on-line system preconcentration system for cadmium, cobalt, copper and nickel determination. Metal ions were sorbed in the minicolumn, from which it could be eluted directly to the nebulizer–burner system of the flame atomic absorption spectrometer (FAAS). Elution of all metals from minicolumn can be made with 0.50 mol L^− 1 HCl or HNO₃. The enrichment factors obtained were 16 (Cd), 24 (Co), 15 (Cu) and 19 (Ni), for 60 s preconcentration time, and 39 (Cd), 69 (Co), 36 (Cu) and 41 (Ni), if used 180 s preconcentration time. Under the optimum conditions, the proposed procedure allowed the determination of cadmium, cobalt, copper and nickel with detection limits of 0.31, 0.32, 0.39 and 1.64 μg L^− 1, respectively, when used preconcentration periods of 180 s. The accuracy of the developed procedure was sufficient and evaluated by the analysis of the certified reference materials NIST 1515 apple leaves and NIST 1570a spinach leaves. The method was applied to the analysis of food samples (spinach, black tea and rice flour).     

An Investigation on the Concentration Efficiencies of Some Macroreticular and Ambersorb Resins Using Radio-Labelled Organic Contaminants Commonly Encountered in Water

Abstract

The extraction efficiencies of the three commercially available Ambersorb®, carbonaceous, polymeric resins, XE-340, XE-347 and XE-348 were evaluated for their use as sorbents for environmental pollutants using four model, radio-labelled water-borne organic contaminants. Their accumulation behaviour was compared with that of the thoroughly-studied Amberlite®, macroreticular XAD-2 (hydrophobic) and XAD-7 (hydrophilic) resins. These model compounds were desorbed from the resins using known volumes of commonly-used solvents to select the solvent for a particular resin(s). In this preliminary study, at <4 μg/L concentrations of the labelled compounds in aqueous solution (pH 5.78), the order of extraction efficiency of the resins was found to be XAD-2 > XAD-7 > XE-340?-347?-348 for organics. Several inherent impurities originally present in the carbonaceous resins were desorbed by solvents during elution. These resins therefore required exhaustive soxhlet purification prior to use. Most of the impurities were identified by gas chromatography/mass spectrometry.     

Preconcentration of trace metals with 2-(methylthio)aniline-functionalized XAD-2 and their determination by flame atomic absorption spectrometry

2-(Methylthio)aniline-modified Amberlite XAD-2 has been synthesized by coupling it through a NNNH group. The resulting chelating resin, characterized by elemental analysis, thermogravimetric analysis and infrared spectra, was used to preconcentrate Cd, Hg, Ni, Co, Cu and Zn ions. Several parameters, such as the distribution coefficient and sorption capacity of the chelating resin, pH and flow rates of uptake and stripping, and volume of sample and eluent, were evaluated. The effect of electrolytes and cations on the preconcentration was also investigated. The recoveries were >96%. The procedure was validated by standard addition and analysis of a standard river sediment material (GBW 08301, China). The developed method was utilized for preconcentration and determination of Cd, Hg, Ni, Co, Cu and Zn in tap water and river water samples by flame atomic absorption spectrometry with satisfactory results. The 3σ detection limit and 10σ quantification limit for Cd, Hg, Ni, Co, Cu and Zn were found to be 0.022, 0.028, 0.033, 0.045, 0.041, 0.064 μg l⁻¹ and 0.041, 0.043, 0.052, 0.064, 0.058, 0.083 μg l⁻¹, respectively.     

Preconcentration and determination of trace elements with 2-aminoacetylthiophenol functionalized Amberlite XAD-2 by inductively coupled plasma-atomic emission spectrometry

2-Aminoacetylthiophenol (AATP)-modified Amberlite XAD-2 has been synthesized by coupling it through NNNH group. The resulting chelating resin, characterized by elemental analysis, thermogravimetric analysis (TGA) and infrared (IR) spectra, was used to preconcentrate Cd, Hg, Ag, Ni, Co, Cu and Zn ions. Several parameters, such as distribution coefficient and sorption capacity of the chelating resin, pH and flow rates of uptake and striping, volume of sample and eluent, were evaluated. The effects of electrolytes and cations on the preconcentration were also investigated. The recoveries were >96%. The procedure was validated by standard addition and analysis of a standard reference sediment material (GBW 07309 China). The developed method was utilized for preconcentration and determination of Cd, Hg, Ag, Ni, Co, Cu and Zn in tap water, river water and sediment samples by inductively coupled plasma-atomic emission spectrometry (ICP-AES) with satisfactory results. The 3σ detection limits for Cd, Hg, Ag, Ni, Co, Cu and Zn were found to be 0.10, 0.23, 0.41, 0.13, 0.25, 0.39 and 0.58 μg l⁻¹, respectively. The relative standard deviation of the determination was <10%.     

Pyrocatechol Violet immobilized Amberlite XAD-2: synthesis and metal-ion uptake properties suitable for analytical applications

Amberlite XAD-2 has been functionalized by coupling it, through the ---N=N--- group, with Pyrocatechol Violet (PV), and the resulting resin has been characterized by elemental analysis, thermogravimetric analysis (TGA) and IR spectra. The resin has been used for preconcentrating Zn(II), Cd(II), Pb(II) and Ni(II) ions prior to their determination by flame atomic absorption spectrometry. The optimum pH values for quantitative sorption are 5, 5–7, 4, and 3 for Zn, Cd, Pb and Ni, respectively. The four metals can be desorbed (recovery ˜98%) with 4 M HNO₃; also, 4 M HCl is equally suitable except for Zn. The sorption capacity of the resin is 1410, 1270, 620 and 1360 μg g⁻¹ resin for Zn, Cd, Ni and Pb, respectively. The effect of F⁻, Cl⁻, NO₃⁻, SO₄²⁻ and PO₄³⁻ on the sorption of these four metal ions has been investigated. They are tolerable in the range 0.01–0.20 M, for Pb. In the sorption of Zn(II) and Ni(II), the tolerance limits of all these ions are upto 0.01 M, whereas for Cd(II), F⁻, NO₃⁻, and PO₄³⁻ have been found to be tolerable upto 0.50, 0.10 and 0.10 M, respectively. The preconcentration factors are 60, 50, 23 and 18 for Zn, Cd, Pb and Ni, respectively. Simultaneous collection and determination of the four metals are possible. Cations commonly present in drinking water do not affect the sorption of either metal ion if present at a concentration level similar to that of water. The method has been applied to determine Zn, Ni and Pb content of well-water samples (RSD ≤9%).     

Determination of trace heavy metals in waters by flame atomic absorption spectrometry after preconcentration with 2,4-dinitrophenyldiazoaminoazobenzene on Amberlite XAD-2

A new column, solid-phase extraction (SPE), preconcentration method was developed for determination of Cd, Co, and Cu ions in natural water samples by flame atomic absorption spectrometry. The procedure is based on the retention of analytes in the form of 2,4-dinitrophenyldiazoaminoazobenzene (DNDAA) complex on a mini column of DNDAA-XAD-2 resin. The effects of pH, eluent type, eluent concentration, eluent volume, resin quantity, sample volume, sample flow rate, and matrix ions (Na, Ca, and Mg) were investigated on the recovery of the metals using model solutions. The detection limit for Cd, Co, and Cu was 0.062, 0.084, and 0.057 μg L⁻¹ and the quantification limit was 0.17, 0.24, and 0.12 μg L⁻¹ respectively. The method was validated by the analysis of a certified reference material with the results being in agreement with those quoted by manufactures. The developed method was applied to the determination of trace metal ions in tap water, river water samples with satisfactory results.     

Comparison of Methods for the Preconcentration of Cadmium (II) Using Amberlite XAD-16 Resin Modified with Anoxybacillus caldiproteolyticus and Geobacillus stearothermophilus as Novel Biosorbents

Abstract

The isolation, identification and characterization of bacteria obtained from soil of Ergani Makam Mountain were performed and the results revealed that the bacteria were thermophilic Anoxybacillus caldiproteolyticus. The characterized bacteria and purchased Geobacillus stearothermophilus were immobilized on Amberlite XAD-16 in order to prepare two biosorbents for preconcentration experiments for the determination of cadmium (II) ions. The produced biosorbents were enriched separately using mini-columns and the analyte was determined by flame atomic absorption spectrometry. The effects of solution parameters were investigated for the separation and preconcentration yields. The recovery efficiencies of Amberlite XAD-16 immobilized separately with A. caldiproteolyticus and G. stearothermophilus were determined to be 98.23?±?2.40 and 98.93?±?1.3 (n?=?5) for the optimum working conditions, respectively. Moreover, the Cd (II) ion was recovered with 10?mL of 1?mol L^?1 of HCl and 2?mL of 0.5?mol L^?1 HNO₃ solutions. The optimum working conditions were determined to be at pH 6.0 and a flow rate of 2?mL min^?1 for both biosorbents. The recovery efficiencies of matrix ions were characterized to investigate the feasibility of the developed preconcentration methods. The accuracy of the proposed methods were controlled by analyzing a SCP Science EnviroMAT Waste Water, Low (EU-L-2) certified reference material. The obtained results were comparable to the certified values. These methods were also applied to the analysis of water samples from Dicle River, Hazar Lake and Diyarbak?r tap water for Cd (II).     

Use of an o-aminobenzoic acid-functionalized XAD-4 copolymer resin for the separation and preconcentration of heavy metal(II) ions

XAD copolymer resins may be functionalized with heavy metal ion-selective ligands either by covalent linkage to the polymer backbone or by impregnation. These resins may be tailored to be specific for certain heavy metals by adjusting the adsorption and elution parameters, thereby enabling simple and cost-effective spectrophotometric and flame atomic absorption spectrometry (FAAS) determinations of these metals without requiring the more sophisticated coupled instrumental techniques. For the synthesis of o-aminobenzoic acid (ABA)-immobilized XAD-4 copolymer resin that is expected to preconcentrate a number of transition and heavy metals, the azo-linkage method was chosen. For this purpose the copolymer was nitrated, reduced to the corresponding amine, converted to the diazonium salt with nitrite, and reacted with o-aminobenzoic acid to produce the XAD-ABA sorbent. This sorbent was capable of preconcentrating Pb(II), Cd(II), Ni(II), Co(II) and Zn(II) from weakly acidic or neutral aqueous solution. The retained metals were eluted with 1.0 M HNO₃ from the resin column, and were subsequently determinated with by flame atomic absorption spectrometry. The developed resin preconcentration and determination method was successfully applied to the analysis of a synthetic metal mixture solution, a certified reference material (CRM) of coal sample, and brackish lake water.     

Column Solid-Phase Extraction with 2-Acetylmercaptophenyldiazoaminoazobenzene (AMPDAA) Impregnated Amberlite XAD-4 and Determination of Trace Heavy Metals in Natural Waters by Flame Atomic Absorption Spectrometry

A column solid-phase extraction (SPE) preconcentration method was developed for the determination of Cd, Co, Cu, Ni and Zn ions in natural water samples by flame atomic absorption spectrometry. The procedure is based on the retention of analytes in the form of 2-acetylmercaptophenyldiazoaminoazobenzene (AMPDAA) complexes on a short column of AMPDAA-XAD-4 resin from buffered sample solution and subsequent elution with hydrochloric acid plus sodium chloride. Important SPE parameters were optimized using model solutions. The loading half-time, t_1/2, for Cd, Co, Cu and Zn was found to be less than 5min, and for Ni the value was 12min. The detection limit for Cd, Co, Cu, Ni and Zn was 0.028, 0.064, 0.042, 0.023 and 0.16µgL^–1, respectively, and the quantification limit was 0.043, 0.11, 0.099, 0.044 and 0.29µgL^–1, respectively. The AMPDAA-XAD-4 resin has good selectivity for Cd, Co, Cu, Ni and Zn over several electrolytes, especially over earth alkaline metals with tolerance limits of 0.05molL^–1. The method was validated by analysing a standard reference material (GBW 08301), and it was found that the results agree with those quoted by the manufactures. The developed method was applied to the determination of trace metal ions in tap water and river water samples with satisfactory results.     

A Chromo-Fluorogenic Naphthoquinolinedione-Based Probe for Dual Detection of Cu2+ and Its Use for Various Water Samples

The presence of an abnormal amount of Cu²⁺ in the human body causes various health issues. In the current study, we synthesized a new naphthoquinolinedione-based probe (probe 1) to monitor Cu²⁺ in different water systems, such as tap water, lakes, and drain water. Two triazole units were introduced into the probe via a click reaction to increase the binding affinity to a metal ion. In day-light, probe 1 dissolved in a mixed solvent system (HEPES: EtOH = 1:4) showed a vivid color change from light greenish-yellow to pink in the presence of only Cu²⁺ among various metal ions. In addition, the green luminescence and fluorescence emission of the probe were effectively bleached out immediately after Cu²⁺ addition. The limit of detection (LOD) of the probe was 0.5 µM when a ratio-metric method was used for metal ion detection. The fluorescence titration data of the probe with Cu²⁺ showed a calculated LOD of 41.5 pM. Hence, probe 1 possesses the following dual response toward Cu²⁺ detection: color change and fluorescence quenching. Probe 1 was also useful for detecting Cu²⁺ spiked in tap/lake water as well as the cytoplasm of live HeLa cells. The current system was investigated using ultraviolet-visible and fluorescence spectroscopy as well as density functional theory calculations (DFT).     

Azocalix[4]pyrrole Amberlite XAD-2: New polymeric chelating resins for the extraction, preconcentration and sequential separation of Cu(II), Zn(II) and Cd(II) in natural water samples

Two novel azocalix[4]pyrrole Amberlite XAD-2 polymeric chelating resins were synthesized by covalently linking diazotized Amberlite XAD-2 with calix[4]pyrrole macrocycles. The chelating resins were used for extraction, preconcentration and sequential separation of metal ions such as Cu(II), Zn(II) and Cd(II) by column chromatography prior to their determination by UV/vis spectrophotometry or flame atomic absorption spectrophotometry (FAAS) or inductively coupled plasma atomic emission spectroscopy (ICP-AES). Various parameters such as effect of pH on absorption, concentration of eluting agents, flow rate, total sorption capacity, exchange kinetics, preconcentration factor, distribution coefficient, breakthrough capacity and resin stability, were optimized for effective separation and preconcentration. The resin showed good ability for the separation of metal ions from binary and ternary mixture on the basis of pH of absorption and concentration of eluting agents. The newly synthesized resins showed good potential for trace enrichment of Cu(II), Zn(II) and Cd(II) metal ions, especially for Cu(II), as compared to the earlier reported resins. The synthesized resins were recycled at least 8-10 times without much affecting column sorption capacity. The presented method was successfully applied for determination of Cu(II), Zn(II) and Cd(II) in natural and ground water samples.     

Pyrogallol Immobilized Amberlite XAD-2: A Newly Designed Collector for Enrichment of Metal Ions Prior to their Determination by Flame Atomic Absorption Spectrometry

 Pyrogallol is covalently linked with the benzene ring of Amberlite XAD-2, through an azo (–N=N–) spacer group and the resulting new polymer characterized by elemental analyses, thermogravimetric analysis (TGA) and infrared (IR) spectra. It has been used for separation and preconcentration of Cu(II), Cd(II), Co(II), Ni(II), Pb(II), Zn(II), Mn(II), Fe(III) and U(VI) prior to their determination by flame atomic absorption spectrometry (FAAS) or fluorimetry (for U(VI) only). The pH ranges for quantitative sorption are 5.5–6.5, 5.5–7.5, 5.5–7.0, 5.5–7.0, 5.5–6.5, 5.5–6.5, 5.5–8.0, 5.5–6.2 and 5.5–6.2, respectively, for the nine metal ions, which can be desorbed (recovery 90–99%) with 4 mol L⁻¹ HNO₃ or HCl. The sorption capacity of the resin has been found to be in the range 4.10 to 6.71 mg of metal g⁻¹ of dry resin. The loading half time (t_1/2) was ≤3.3 min for all the metal ions. The effects of NaF, NaCl, NaNO₃, Na₂SO₄, and Na₃PO₄ on the sorption of these metal ions (0.2 μg mL⁻¹) are reported. The Ca(II) and Mg(II) are tolerable up to a concentration level of 40–400 and 25–240 μg mL⁻¹, respectively. The enrichment factor for Cu(II), Cd(II), Co(II), Ni(II), Pb(II), Zn(II), Mn(II), Fe(III) and U(VI) has been found to be 65, 40, 65, 120, 25, 160, 120, 140, and 70 (concentration level 2–25 ng mL⁻¹), respectively. The limit of detection for these nine metal ions is 5.0, 1.3, 5.0, 4.0, 25.0, 0.5, 1.0, 2.0 and 1.0 ng mL⁻¹, respectively. After enrichment on the present matrix, the flame AAS method has been applied to determine these metal ions (except U) in river water samples (RSD ≤ 7%) and well water (RSD ≤ 8%). Uranium present in well water samples has been enriched on the present matrix and determined by a fluorimetric method (RSD ≤ 6%). The cobalt present in pharmaceutical vitamin tablets was also preconcentrated with the aid of the present chelating resin and determined by FAAS to be 1.93 μg g⁻¹ (RSD ∼4%). Received May 16, 2000. Revision April 3, 2001.     

高效液相色谱-电感耦合等离子体质谱法测定饮用水中碘酸根和碘离子

提出了高效液相色谱-电感耦合等离子体质谱法测定饮用水中碘酸根和碘离子的方法。饮用水样品通过Dionex IonPac AS14阴离子交换柱及AG14保护柱分离碘酸根和碘离子,用50mmol.L-1碳酸铵溶液(用氨水调至pH 9.9)作流动相进行淋洗。于洗脱液中用电感耦合等离子体质谱法分别测定碘酸根和碘离子的含量,两者的线性范围均为0.20～300μg.L-1,检出限(3S/N)依次为0.09μg.L-1和0.13μg.L-1。以饮用水为基体加入两个不同浓度水平的标准溶液按方法分析后,求得方法的回收率及精密度为①碘酸根回收率在100.5%～113.0%,相对标准偏差(n=8)在1.2%～2.8%之间;②碘离子回收率在101.9%～110.7%,相对标准偏差(n=8)在1.3%～2.0%之间。     

气相色谱法测定生活饮用水中2-氯苯酚和2-甲苯酚

采用固相萃取(SPE)小柱固相萃取,建立了生活饮用水中2-氯苯酚和2-甲苯酚的气相色谱检测方法。用盐酸调节水样至p H 5.0,用SPE小柱固相萃取后以乙酸乙酯洗脱,以CD-5色谱柱进行分离,氢火焰离子化检测器检测2-氯苯酚和2-甲苯酚的含量。2-氯苯酚和2-甲苯酚的质量浓度在2.00~40.0μg/L范围内与色谱峰面积线性关系良好,检出限分别为0.03,0.04μg/L;加标回收率分别为87.2%~93.9%,89.0%~94.8%;测定结果的相对标准偏差均小于2%(n=7)。该方法具有检出限低、操作简便等优点,适用于生活饮用水中2-氯苯酚和2-甲苯酚的监测分析。     

Speciation of Cr(III) and Cr(VI) in water after preconcentration of its 1,5-diphenylcarbazone complex on amberlite XAD-16 resin and determination by FAAS

A simple and sensitive method for the speciation, separation and preconcentration of Cr(VI) and Cr(III) in tap water was developed. Cr(VI) has been separated from Cr(III) and preconcentrated as its 1,5-diphenylcarbazone complex by using a column containing Amberlite XAD-16 resin and determined by FAAS. Total chromium has also been determined by FAAS after conversion of Cr(III) to Cr(VI) by oxidation with KMnO₄. Then, Cr(III) has been calculated by subtracting Cr(VI) from the total. The effect of acidity, amount of adsorbent, eluent type and flow rate of the sample solution on to the preconcentration procedure has been investigated. The retained Cr(VI) complex was eluated with 10 ml of 0.05 mol l⁻¹ H₂SO₄ solution in methanol. The recovery of Cr(VI) was 99.7±0.7 at 95% confidence level. The highest preconcentration factor was 25 for a 250 ml sample volume. The detection limit of Cr(VI) was found as 45 μg l⁻¹. The adsorption capacity of the resin was found as 0.4 mg g⁻¹ for Cr (VI). The effect of interfering ions has also been studied. The proposed method was applied to tap water samples and chromium species have been determined with the relative error <3%.