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The purpose of the study was utilization of emission atomic absorption spectrometry with excitation in induction-coupled plasma for determination of Cu(II), Pb(II), Cd(II), Co(II) i Ni(II) in plant material. The possibility of using inorganic carrier for separation of trace amounts of heavy metals from aqueous solution is presented. Optimal conditions for coprecipitation of metal ions with Mg(OH)2 as well as for their determination by means of the ICP-AES method are described. The conditions of heavy metals separation and concentration make possible determination of the metals in the concentration from 0.01 to 0.20 microgram/ml by the ICP-AES. As a result simple method was elaborated for group concentration and determination of the above mentioned metals in samples of plant material. The studied food products were mineralized with concentrated HNO3, HClO4 and perhydrol. The method of preconcentration and determination was used for metals determination in dairy products in concentrations about 5 x 10(-5)%. As a result simple and economical method was elaborated for group preconcentration and determination of the above mentioned metals in samples of plant material.
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PMID:[The determination of Cu, Cd, Pb, Co and Ni in material with the use of the ICB-AES method]. 1177 Nov 14

Concentrations, distributions and mobility of chemical elements were investigated in reduced sulfur-rich estuarine sediments located in western Finland. The main objective was to determine the possible extent of metal leaching when dredged masses of these sulfur-rich sediments are dumped on the land and thus exposed to air. When dredged, the reduced sulfur in the sediments oxidises resulting in a lowering of pH, which in turn is expected to leach metals. The study area is an artificial lake claimed from the Botnian sea in 1962. In this lake, several mass-kills of fish have occurred, believed partly to be due to dredging. Two sediment samples (0-50 and 50-100 cm) were taken from 39 sampling points in the lake. These samples were leached in aqua regia (2:2:2 HNO3/HCl/H2O1) and analysed for Fe, Al, Mg, Ca, K, P, Na, Mn, Zn, Ba, V, Sr, Cr, Ni, Cu, Co, As, Pb, B, Mo and Cd with ICP-AES. Sulfur and organic carbon were analysed with Leco. In a controlled laboratory experiment, the sediments were allowed to oxidise for 1 year while moisturised with deionised water every month. The pH and conductivity were determined in the beginning of the experiment (reduced state) and in the end (oxidised state). In the supernatants in the oxidised states the amount of leached metals (Na, Al, Mn, Zn, Sr, Co, Ni, Cu, Cd, Cr, Pb, U, Li, Rb and As) were determined with ICP-MS. The sediments were found to contain low levels of toxic metals but, as expected, high concentrations of sulfur. In the experiment, pH was lowered (down to 3.0) and the conductivity increased in all samples due to oxidation and release of metal ions. The extent of leaching varied between 0.03% for As and 12.3% for Na. Critical pH values, at which high amounts of metals begin to leach, were obtained graphically. These values varied between 4.8 (Ni) and 3.3 (Cr). Not all elements were controlled by pH, e.g. Mn correlated well with its aqua regia leachable concentration. In a planned dredging operation in the area some 23,300 t (10,500 m3) (dry wt.) of sediments will be dredged. The amounts of metals likely to be leached, according to the results from this study, are as follows (kg): Al (1710), Mn (1230), Zn (59), Sr (39), Co (13), Ni (12), Cu (2) and less than 1 kg of Cd-Cr-As-Pb.
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PMID:Concentrations and leachability of chemical elements in estuarine sulfur-rich sediments, W. Finland. 1184 56

An on-line matrix separation/inductively coupled plasma mass spectrometry (ICP-MS) method is proposed for the determination of trace amounts of phosphorus in high purity tantalum metal, tantalum (V) oxide, and tantalum pentaethoxide. In the present method, the matrix tantalum in the sample solution was adsorbed on the anion exchange resin, and phosphorus (phosphate ion) was eluted with the carrier solution of HF and HNO3 mixture. Then, the effluent solution was subsequently mixed with bismuth solution and aqueous ammonia solution to coprecipitate phosphate together with bismuth hydroxide. The precipitate formed was collected on the in-line membrane filter to wash out nitric acid with pure water, and then dissolved with hydrochloric acid. The obtained phosphorus sample solution was introduced directly into the nebulizer of ICP-MS for the determination of phosphorus. Phosphorus was determined at the molecular ion signal of 31P16O+ (m/z 47). The detection limit (3sigma) of phosphorus in the present method was 1.3 ng mL(-1) as the sample solution basis, and the relative standard deviation for 30 ng mL(-1) of phosphorus in the standard solution was 4.3% in the replicate measurements (n=11). The present method was applied to the analysis of high purity tantalum materials. The concentrations of phosphorus in tantalum samples were in fairly good agreement with those obtained by glow discharge mass spectrometry (GDMS).
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PMID:Determination of trace phosphorus in high purity tantalum materials by inductively coupled plasma mass spectrometry subsequent to matrix separation with on-line anion exchange/coprecipitation. 1193 29

Multielement monitoring of the concentrations of trace metals dissolved in surface seawater collected at sampling stations along the ferry track between Osaka and Okinawa was performed by ICP-MS (inductively coupled plasma mass spectrometry). The surface seawater samples were collected by an automated sampling system for on-board sampling, which was installed on the bottom of a ferryboat. A part of each seawater sample was filtered with a membrane filter (pore size of 0.45 microm) immediately after sampling. Both filtered and non-filtered seawater samples were acidified to pH ca. 1 by adding conc. HNO3, and were subjected to chelating resin preconcentration for the determination of trace metals by ICP-MS, where the concentrations of analyte metals in the filtered and non-filtered seawater samples were referred to as the dissolved and total concentrations, respectively. According to the thus-obtained results, it was found that most trace metals, especially below the 0.01 microg l(-1) as the dissolved and total concentrations, sensitively reflected the environmental pollution in the Osaka Bay and Seto Inland Sea area, as well as near to the Bungo Canal and the outlet of Kagoshima Bay.
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PMID:Multielement monitoring for dissolved and acid-soluble concentrations of trace metals in surface seawater along the ferry track between Osaka and Okinawa as investigated by ICP-MS. 1199 Jun 16

The objective of the work carried out was to recommend protocols for the collection, filtration (0.45 microm) and preservation of surface water samples for the subsequent determination of total 'dissolved' Hg. Cold vapour (CV) ICP-MS was employed to determine Hg; samples were acidified to a strength of 4 mol l(-1) HCl and 1% NaBH4 was used as the reducing agent in-line. Four types of 125 ml bottles were studied (Teflon, fluorinated ethene propene copolymer, FEP; high density polyethylene, HDPE; polyethylene terephthalate copolyester, PET; polypropylene, PP), together with three cleaning methods (EPA Methods 1631, 1638 and a rinse with reverse osmosis deionised water, 'MilliQ'). The transmission properties of the four materials were also studied to evaluate the potential for contamination from atmospheric Hg0. Results of this bottle study (n = 195), all below the detection limit of 0.5 ng l(-1), indicate that the bottles of choice, from an economic and time-saving perspective, are HDPE and PP, the latter being preferable if the sample is to be stored in a contaminated atmosphere. The bottles would be used on a once-only basis, negating the need for labourious and costly cleaning on repeat use. A simple rinse with MilliQ water would suffice prior to use. Twelve 0.45 microm filter systems (mostly Millipore and Gelman) were studied for (a) their potential Hg contamination properties and (b) their retention of Hg, possibly in colloidal form, during filtration. Ottawa River water, spiked at 50 ng l(-1) Hg, was used as a control sample. Again blank values were all negative, indicating contamination was not a concern but different recoveries of Hg were obtained across the different systems. The optimum systems to use, in that they provided maximum recovery (ca 80%) of Hg, are the Millipore Sterivex capsule and the Millipore Millex disc, both based on the hydrophilic Durapore membrane. The lowest recoveries (23-36%) were found with the Gelman AquaPrep systems and the Millipore HN nylon filter. Four control samples, Ottawa, Rideau and Gatineau Rivers, and a MilliQ blank, were used to study three preservation approaches, in the media: 0.5% BrCl, 2% HCl and 0.04% K2Cr2O7 in 1% HNO3. Mercury was stable for 28 days in a medium of 0.5% BrCl in all four samples but the other two media showed a loss of up to ca 20% Hg over this time frame, the loss being sample and time dependent. This may be a species transformation which is not detected by CV-ICP-MS from an HCl medium but this requires further investigation. Mercury was stable over the 28 days in the spiked blank MilliQ sample for all three preservation media.
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PMID:Sample collection, filtration and preservation protocols for the determination of 'total dissolved' mercury in waters. 1208 Oct 47

Selenium concentrations and its spatial distribution in soils, spermatophytes and bryophytes (mosses) around the Cockle Creek Zn-Pb smelter, New South Wales were studied from May to November 2000. Selenium was determined by ICP-MS on soils digested in nitric and hydrochloric acid (HNO3:HCl = 3:1), and plant samples digested in distilled concentrated nitric acid. At distances greater than 3 km, selenium in soils, spermatophytes and bryophytes converge to uniform values, which are considered to represent the background value. Mean selenium in soils around the smelter is two times higher than the background value. Mean concentration of selenium in plants around the smelter is three times greater than that for background plants. Selenium from 'in site' bryophyte is twice that found in the background bryophyte. The transfer coefficients of selenium between plants and soils are low, especially at a distance less than 1 km from the smelter. However, mosses show the reverse trend. This study indicates that the Zn-Pb smelter is one of the anthropogenic point sources of selenium pollution in the Lake Macquarie district.
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PMID:Selenium in soils, spermatophytes and bryophytes around a Zn-Pb smelter, New South Wales, Australia. 1210 67

A BCR standard reference material of lichen (CRM 482) was used to validate an analytical procedure consisting of a microwave oven digestion associated with ICP-OES, ICP-MS and GFAAS techniques for the analysis of trace elements (Al, B, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Ti, V and Zn) in biomonitor samples. Two different acid mixtures were used: (a) 7 ml of HNO3, 1 ml of H2O2; (b) 7 ml of HNO3, 1 ml of H2O2 and 200 microl of HF; all digestions were carried out using 100-250 mg samples brought to a final volume of 50 ml. The validation of the procedure was carried out by two laboratories in terms of accuracy and precision; the former was estimated as percentage recovery by comparing experimental data with certificate values; the latter evaluated according to ISO standard 5725. Real lichen samples were analysed too with the procedures above described. In certified CRM 482 and real lichen samples the procedure with HF showed higher recovery values for Al, Ti, V, Ba and Fe than the procedure without HF. For all the other elements the two procedures gave comparable results both in terms of accuracy and precision. The recovery obtained with HF procedure for all the elements was generally better than 90-103%.
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PMID:Comparison of different analytical procedures in the determination of trace elements in lichens. 1214 18

A method for the determination of ultratrace amounts of boron in high-purity tantalum materials [tantalum metal, tantalum(v) oxide, tantalum pentachloride and tantalum pentaethoxide] is described. On-line anion-exchange matrix separation combined with inductively coupled plasma mass spectrometry (ICP-MS) was employed for the determination of boron at the ng g(-1) level. Tantalum materials were dissolved using HF and/or HNO3 prior to analysis. The loss of boron in the sample preparation procedure was examined as the recovery of boron by adding a definite amount of boron to each tantalum material sample before decomposition, and it was almost negligible. In an anion-exchange method using 0.1 M HF carrier solution, tantalum and boron in the sample solution were first adsorbed on a strongly basic anion-exchange resin. Next, boron was eluted from the resin with 5 M HCl, whereas tantalum was retained strongly adsorbed. The eluted boron was introduced directly into the ICP-MS system for quantitative analysis at m/z 10 and 11. Because of the long elution time of boron, the transient signal was integrated in the time range 70-300 s on the chromatogram. Although the elution of boron in the time range was ca. 40% of total boron in the sample solution injected, the determination limits (10sigma) obtained by the present method were 30, 25, 15 and 13 ng g(-1) for tantalum metal, tantalum(v) oxide, tantalum pentachloride and tantalum pentaethoxide, respectively. The method was applied to the determination of boron in commercially available high-purity tantalum materials and it was found that the concentrations of boron were in the ng g(-1)-microg g(-1) range.
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PMID:Determination of boron in high-purity tantalum materials by on-line matrix separation/inductively coupled plasma mass spectrometry. 1217 52

The selenium determination in biological materials by the classical fluorometric method (FM) is time-consuming and also hazardous, as it requires the destruction of the organic matrix samples with hot HNO3/HClO4 mixtures prior to analysis. Accordingly, commercial analytical laboratories are increasingly using faster instrumental methods; for sample digestion, avoid using HClO4. Because of these procedural changes, the results obtained by commercial laboratories may be unreliable, especially for samples containing Se in organic forms. One such "difficult" substrate is Se yeast, which contains most of its Se as selenomethionine. To establish which methods for Se analysis and sample digestion are applicable, samples of Se yeast and of selenomethionine standards were sent to laboratories employing either flame atomic absorption spectrometry (FAAS), inductively coupled plasma-mass spectrometry (ICP-MS), or hydride generation atomic absorption spectrometry (HGAAS). The results were compared with those obtained by FM and non-destructive instrumental neutron activation analysis (INAA). ICP-MS, after microwave digestion of sample with HNO3/H2O2, produced results within 5% of the expected values, as did those obtained by FM and INAA. With FAAS, acceptable results were obtained after digestion with HNO3/HCl. With HGAAS, sample digestion with HNO3/H2O2 produced values that were systematically elevated by about 10% and exhibited standard deviations of > or = 10%. Thus, current methods of sample digestion are applicable for Se yeast analysis by ICP-MS and FAAS, but not by HGAAS.
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PMID:Evaluation of methods for total selenium determination in yeast. 1229 28

A new method for the determination of ultra-trace level of lanthanides such as La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm Yb and Lu in human rib is explored. Closed-vessel microwave digestion with concentrated HNO3 is used for the sample preparation and the digested analyte is directly analyzed by ICP-MS. The method is sensitive and accurate and, is efficient for the determination of the fourteen lanthanides listed above. Detection limit for various elements ranges from 0.0007 microgram/L to 0.005 microgram/L. Calibration plots exhibit good linearity with high linear correlation coefficient r > or = 0.997. Recoveries of spiked samples ranges from 93.7% to 115.4%. Precision is < 3% RSD. Rhodium is used as the internal standard to compensate the signal suppression caused by the sample matrix. Isobaric overlap of polyatomic ions caused by matrix oxide/hydroxide of barium is corrected by interference correction factor. Two standard reference materials, namely "Human Hair GBW07601" and "Wheat Flour GBW08503" are used for quality control of the analyzed samples.
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PMID:[Application of microwave dissolution and inductively coupled plasma-MS spectrometry for determination of ultra-trace level of lanthanides in human rib]. 1260 26


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