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1.
Liping Fang Wei Wang Haiping Liu Henan Qiu Yaxian Zhao Bingwen Lu 《International journal of environmental analytical chemistry》2015,95(10):879-893
Two freshwater sediments certified reference materials (CRMs) for 16 polycyclic aromatic hydrocarbons (PAHs) have been developed by the Institute for Environmental Reference Materials (IERM) of Ministry of Environmental Protection (MEP) in China. The methodology for preparing the CRMs of PAHs in sediments is described in this paper. The collected natural sediment samples were air-dried, ground, homogenised, packed, sterilised and tested on stability and homogeneity. Homogeneity results showed that the between-unit variation was confirmed to be below 4.5% for each compound. Stability was assessed after storage of samples for 16 months at temperature less than 30°C and in shade. The certification of the natural sediment matrix CRMs for PAHs was based on the agreement of results using different analytical techniques including gas chromatography/mass spectrometry (GC/MS) and reversed-phase liquid chromatography (LC) by no less than eight collaborating laboratories including IERM. Results of the homogeneity showed that the calculated ubb′ was 0.9–2.5% for environmental river standard-4 (ERS-4) and 9–2.3% for environmental lake standard-1 (ELS-1), whereas stability results of total 16 PAHs indicated that the calculated urel,lts was 4.2% for ERS-4 and 2.2% for ELS-1. Certified values of 16 PAHs in ERS-4 varied from 8.5 to 167 μg/kg and ranged from 0.036 to 2.8 mg/kg in ELS-1.The good comparability, together with the independent confirmation of the assigned mass fraction by using different methods, confirmed that the CRMs are suitable for the method validation and quality control in soil or sediments analysis. 相似文献
2.
Wim P. Cofino 《Mikrochimica acta》1996,123(1-4):151-161
The comparability of data from accredited laboratories is not always as good as customers would desire. A number of reasons for this fact are given. Clients of laboratories do not specify methodology, which may lead to the application of systematically different methods or to methodology with improper performance characteristics. Laboratories do not always validate methodology sufficiently which is, however, among others provoked by a lack of reference materials. It is argued that accreditation cannot enforce comparability on itself, but needs to be embedded in a measurement infrastructure. The quality systems which underly accreditation form a basic element. In addition, adequate methods, good laboratory performance studies and certified reference materials are required. 相似文献
3.
P. Quevauviller G. Rauret R. Rubio J.-F. López-Sánchez A. Ure J. Bacon H. Muntau 《Analytical and bioanalytical chemistry》1997,357(6):611-618
The ecotoxicity and mobility of trace elements in soils are often evaluated through analytical results resulting from operationally-defined
determinations (single and sequential extractions), e.g. based on EDTA, acetic acid etc. extractions. The significance and
comparability of these results is highly dependent on the procedures used (standardized protocols or standards adopted by
international bodies) and their quality control relies on the availability of reference materials certified following these
strictly applied procedures. Recognizing the need to harmonize some of the extraction schemes currently used for soil analysis,
the Measurements and Testing Programme (formerly BCR) has organized a series of interlaboratory studies, the first aim of
which was to evaluate EDTA- and acetic acid-extraction procedures and the second objective was to certify reference materials
for their extractable trace element contents. Two sewage amended soils have been prepared for this purpose, originating respectively
from Scotland and Catalonia. This paper describes the preparation, homogeneity and stability studies, and gives an overview
of the certification campaign.
Received: 6 May 1996/Revised: 14 June 1996/Accepted: 27 June 1996 相似文献
4.
Maurizio Bettinelli Sandro Spezia Umberto Baroni Gabriele Bizzarri 《Mikrochimica acta》1996,123(1-4):217-230
The determination of trace elements in fossil fuels is of primary importance to achieve correct evaluation of environmental impact of power plants. The characterization of coals and fuel oils can be carried out by several analytical techniques such as ICP-MS, FI-HG-AAS, ETA-AAS, ICP-AES and XRF. The accuracy of the analysis, done to routine basis, can be systematically checked by means of the reference materials available or comparing the results obtained by different techniques. Quality control activities in the field of trace element determination in fossil fuels (coal and fuel oil) are described. The determination of As, Hg and Se in coals was carried out by different techniques (NAA, FI-HG-AAS and FI-ICP-MS) together with the determination of several trace metals in residual fuel oils by NAA, ETA-AAS and ICP-MS. The use of certified reference materials in order to check the accuracy of procedures is discussed and the results obtained for NIST 1632a and NIST 1632b (coal samples) and NIST 1634b and NIST 1619 (fuel oil samples) are reported. 相似文献
5.
6.
In recent years, the classical Soxhlet extraction of PAHs and PCBs from matrices such as soil, sediments, sludges and related matrices has been substituted by faster and less-solvent-consuming automated techniques. This paper describes the performance characteristics of fluidized-bed extraction (FBE), which has been compared to other approaches and been optimized using a quality control material.SI-traceable reference materials from the European Commission have been used to validate the developed method and establish an analytical protocol. Good correlations with Soxhlet extraction were observed and certified values of the CRMs used, could be confirmed in all cases. 相似文献
7.
Ben Griepink 《Mikrochimica acta》1988,96(1-6):75-85
The way of certification of trace element contents in a sample of single cell protein (SCP) is presented together with the results of the homogeneity and stability studies, carried out on this sample (BCR 274). The elements As, Cd, Co, Cu, Mn, Pb, Se and Zn are certified using different spectrometric, electrochemical or activation techniques after a thorough sample treatment. The material is not only useful in SCP-analysis, but can also be applied for analytical background measurements and control or for the analysis of similar materials (e.g. sea food). 相似文献
8.
9.
Hetter KM Bellis DJ Geraghty C Todd AC Parsons PJ 《Analytical and bioanalytical chemistry》2008,391(6):2011-2021
The production of modest quantities of candidate bone lead (Pb) reference materials is described, and an optimized production
procedure is presented. The reference materials were developed to enable an assessment of the interlaboratory agreement of
laboratories measuring Pb in bone; method validation; and for calibration of solid sampling techniques such as laser ablation
ICP-MS. Long bones obtained from Pb-dosed and undosed animals were selected to produce four different pools of a candidate
powdered bone reference material. The Pb concentrations of these pools reflect both environmental and occupational exposure
levels in humans. The animal bones were harvested post mortem, cleaned, defatted, and broken into pieces using the brittle
fracture technique at liquid nitrogen temperature. The bone pieces were then ground in a knife mill to produce fragments of
2-mm size. These were further ground in an ultra-centrifugal mill, resulting in finely powdered bone material that was homogenized
and then sampled-scooped into vials. Testing for contamination and homogeneity was performed via instrumental methods of analysis.
相似文献
Patrick J. ParsonsEmail: |
10.
Elemental fractionation of Si, Al, Ti, Fe, Ca, Mn, P, and Ba in five marine sedimentary reference materials: results from sequential extractions 总被引:1,自引:0,他引:1
We report on the elemental results from sequential extractions of BCSS-1 (marine sediment), MESS-1 (estuarine sediment), MAG-1 (marine mud), SCo-1 (Cody shale), and NIST-1c (argillaceous limestone) to encourage future comparisons of sequential extraction results within the marine geochemical and paleoceanographic communities. We measured Si, Al, Ti, Fe, Mn, Ca, P, and Ba in sequential de-ionized water (loosely-bound), MgCl2 (exchangeable), acetic acid (carbonate), hydroxylammonium hydrochloride (oxide), H2O2 (organic), Na2CO3 (opal), and residual (lithogenic) leaches. The protocol and selected elements were tailored to be most relevant to paleoceanographic geochemical studies instead of to environmental studies. Our results show that the sequential extraction procedure faithfully yields elemental distributions that are consistent with individual SRM lithologies. Our results also show that the procedure is typically reproducible within approximately 15%. However, in almost all cases, the procedure suffers from a systematic under-recovery of material when compared with the certified, bulk chemical analysis, and the under-recovery appears to be related to the lithology of the SRM. Similar under-recovery appears to be typical of sequential extraction procedures as reported by other previous studies. While this is problematic in assessing closure, it does not diminish the potential of inter-lab comparisons and first-order accuracy comparisons. We found that the elemental totals for the sequential extractions of MAG-1 compared best with the certified, bulk totals, and we recommend using this SRM to facilitate future accuracy assessments and inter-lab comparisons. 相似文献
11.
Philippe Quevauviller Eddie A. Maier Bernard Griepink Umberto Fortunati Kristien Vercoutere Herbert Muntau 《Trends in analytical chemistry : TRAC》1996,15(10):504-513
For the wide variety of soil/sludge matrices encountered in analytical practice, a range of CRMs should be available to verify the analytical quality control of any determination carried out, using samples which should be as similar as possible to real soil and sludge samples so that the method's performance may be tested under real analytical conditions. This paper presents basic requirements for the preparation of soil and sludge CRMs for the quality control of trace element determinations (total and extractable contents, following strict extraction protocols), and gives recent examples of new certifications successfully concluded by the SM&T programme of the European Commission. 相似文献
12.
Pressurized liquid extraction with an integrated carbon trap (PLE-C) has recently been developed for fast and efficient analysis
of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in food and feed. The method has also been tested, but not verified,
for use on more complex soil samples, such as soil, sediment and fly ash. Hence, the primary aim of this study was to verify
that PLE-C can produce reliable data for PCDDs/PCDFs in various abiotic matrixes. A second aim was to find a replacement for
the previously used AX21 active carbon that is currently not commercially available. The performance of the PLE-C was evaluated
using both single congener concentrations and toxic equivalency potentials (TEQ-pot) of three (soil, sediment and fly ash)
certified reference materials. The results clearly show that PLE-C can be used for abiotic samples and that a commercially
available carbon (Norit SA 4PAH HF) can replace the AX-21 carbon in the carbon trap. The TEQ-pot values obtained for the soil
and sediment samples were within the uncertainty limits of the corresponding certified values, as were the determinations
of single congener concentrations. PLE-C therefore has great potential for determination of PCDDs/PCDFs in soil and sediment
samples. The TEQ-pot result for the fly ash was slightly lower than the certified TEQ-pot value, but it is still within the
uncertainty limits of the certified value. Out of the single congener concentrations all but four (out of 17) agreed well
with the values. Hence, PLE-C may potentially be used also for fly ash—after slight modifications. The integrated PLE-C and
cleanup procedure is less labour-intensive than traditional methods such as Soxhlet extraction followed by a multistep cleanup,
and consumes smaller quantities of ultrapure solvents than the commonly used Power-Prep system. In addition, PLE-C is capable
of larger sample throughputs than the conventional methods. Thus, PLE-C is a promising alternative to the currently used sample
preparation procedures for dioxins in abiotic samples.
Figure PLE with integraded carbon trap for rapid PCDD/Fs analysis
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
13.
The use of inductively coupled plasma mass spectrometry (ICP-MS) in the production of environmental certified reference materials by the National Research Council of Canada is reviewed. Particular emphasis is placed on the use of isotope dilution ICP-MS. Results for fresh and saline natural waters, fish tissues and sediments are presented to illustrate the impressive capabilities of this technique. 相似文献
14.
Analyses of freshwater are routinely performed by a number of organisations to monitor the levels of major elements. In order to improve and control the quality of such determinations, the Community Bureau of Reference (BCR) has organised a certification campaign to produce two reference materials (CRM 398, low element content and CRM 399, high element content) certified for their contents of Al, Ca, Cl, Fe, Mg, Mn, K, Na, P and S. These materials were carefully prepared (addition of the elements mentioned in the form of ammonium salts or nitrates to silica free deionised water) and their homogeneity and long term stability were verified. This paper presents the certification work performed. 相似文献
15.
Pirjo Sainio Irma Mäkinen Jaap-Willem Hutter Theo den Ouden Mikael Krysell 《Accreditation and quality assurance》2006,11(3):116-121
The international joint project HYCREF (Contract No. G6RD-CT-2002-00854), funded by the European Commission in the 5th Framework programme, aimed to develop methods to prepare homogeneous and stable reference materials of water, soil, and waste contaminated with mineral oil hydrocarbons and to certify the mineral oil content by gas chromatographic methods. The results of a feasibility study for the preparation of three soil reference materials are discussed in this paper, and for the preparation of three waste reference materials in the second part (Koch et al., Accred Qual Assur submitted for publication). The soil materials were selected to represent different soil types and contamination levels. The project plan set three requirements for these reference materials: uncertainty in the mineral oil content resulting from the certification exercise <5%, a sample inhomogeneity of <3% and a minimum long-term stability of 5 years. For the most part, these requirements were met within this project. 相似文献
16.
K. Vercoutere U. Fortunati H. Muntau B. Griepink E. A. Maier 《Fresenius' Journal of Analytical Chemistry》1995,352(1-2):197-202
The determination of various heavy metals in soils and sludges provides an indication for their degree of contamination. Therefore the reliability of such determinations is of utmost importance. Quality assessment can be performed by using adequate certified reference materials. Because of their success, the present supplies of the BCR CRM 142, CRM 143 and CRM 145 are exhausted. The Measurement and Testing Programme (BCR) of the Commission of the European Communities decided to replace them. After a careful preparation procedure of materials sufficiently similar to the exhausted ones and a homogeneity and stability study, the new materials were certified for a series of trace elements also including their aqua regia soluble fraction. Indicative values for other elements are given as well. 相似文献
17.
S. Caroli G. Forte M. Alessandrelli R. Cresti M. Spagnoli S. D'Ilio J. Pauwels G. N. Kramer 《Microchemical Journal》2000,67(1-3)
In the context of the general mandate of the European Union Community Reference Laboratory (CRL) for residues in living animals and their products established at the Istituto Superiore di Sanità, a pilot study was undertaken to assess the possibility of producing a new certified reference material (CRM) for trace elements in a matrix of honey. The elements considered were As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sn, V and Zn. Their determination was performed by inductively coupled plasma (ICP)-based techniques. Data obtained with different ICP techniques were generally in good agreement. In light of these results, the next step was the effective production of a candidate CRM in a honey matrix. In the preliminary phase, two different types of honey, i.e., Eucalyptus (solid and sticky) and Robinia (viscous and sticky), were pretreated at the Institute for Reference Materials and Measurements, Joint Research Centre, European Commission (EC-JRC-IRMM) in order to produce the materials candidate for the certification process. Approximately 600 ampoules were thus produced for the Robinia honey and 450 ampoules for the Eucalyptus honey, each ampoule containing 5 g of an aqueous solution of honey (with 20% and 30% high purity water, respectively) and sealed under inert gas (Ar). A ring test to determine the levels of the chemical elements and a long-term study to evaluate the stability of the samples is in progress. Tentative figures for the analytes of interest are (in ng g−1): Robinia, As, 1.28±0.09; Cd, 0.59±0.08; Cr, 2.36±0.21; Cu, 57.6±3.2; Fe, 209±9; Mn, 90.8±3; Ni, 18.1±0.6; Pb, 23±1.5; Sn, 8.10±0.35; V, 1.19±0.37; and Zn, 178±4; Eucalyptus, As, 3.18±0.21; Cd, 0.70±0.08; Cr, 2.73±0.22; Cu, 141±6; Fe, 926±16; Mn, 1905±81; Ni, 7.77±0.4; Pb, 138±4; Sn, 7.97±0.16; V, 3.47±0.15; and Zn, 405±9. 相似文献
18.
Wise SA Poster DL Kucklick JR Keller JM Vanderpol SS Sander LC Schantz MM 《Analytical and bioanalytical chemistry》2006,386(4):1153-1190
For the past 25 years the National Institute of Standards and Technology (NIST) has developed certified reference materials
(CRMs), known as standard reference materials (SRMs), for determination of organic contaminants in environmental matrices.
Assignment of certified concentrations has usually been based on combining results from two or more independent analytical
methods. The first-generation environmental-matrix SRMs were issued with certified concentrations for a limited number (5
to 10) of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). Improvements in the analytical certification
approach significantly expanded the number and classes of contaminants determined. Environmental-matrix SRMs currently available
include air and diesel particulate matter, coal tar, marine and river sediment, mussel tissue, fish oil and tissue, and human
serum, with concentrations typically assigned for 50 to 90 organic contaminants, for example PAHs, nitro-substituted PAHs,
PCBs, chlorinated pesticides, and polybrominated diphenyl ethers (PBDEs).
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
19.
Malachite green oxalate (MG oxalate) and leucomalachite green (LMG) have been prepared and certified as pure reference materials.
The purities of MG oxalate and LMG were assessed by high-performance liquid chromatography–diode array detection (HPLC–DAD),
nuclear magnetic resonance (NMR) spectroscopy, differential scanning calorimetry (DSC), Karl Fischer titration, ashing and
thermogravimetric analysis (TGA). MG oxalate was purified by supercritical fluid extraction (SFE). Prior to purification,
commercial MG oxalate purity was estimated to be about 90%. The main impurities present in SFE-purified MG oxalate were identified
and quantified using HPLC–DAD. The main impurities were found to be monode-MG (monodemethylated MG oxalate synthesis impurity),
4-(dimethylamino)benzophenone (4-DMABP), MG-carbinol and LMG. The homogeneity of both reference materials was also determined.
Issues associated with the stability of LMG and MG oxalate in solution forced an extensive study investigating different parameters
i.e. solvent, acid, analyte concentration and temperature. MG oxalate (100 μg/mL) was found to be stable in acetonitrile containing
1% v/v glacial acetic acid for at least 155 days and LMG (100 μg/mL) was stable in acetonitrile for at least 133 days. The
final purity value for MG oxalate was 94.3 ± 1.4% m/m at the 95% confidence interval (or 67% m/m if MG cation is reported).
For LMG, the certified purity was found to be 98.8 ± 0.8% m/m at the 95% confidence interval.
Figure Calibration reference materials for malachite green and leucomalachite green, certified for purity, are essential in characterising
these key analytes in a fish matrix reference material 相似文献