30 research outputs found
IMEP-31: Total Arsenic, Cadmium, Copper, Lead and Mercury, as well as Extractable Cadmium and Lead in Mineral Feed - Interlaboratory Comparison Report
The Institute for Reference Materials and Measurements (IRMM) of the Joint Research Centre (JRC), a Directorate-General of the European Commission, operates the International Measurement Evaluation Programme® IMEP. It organises interlaboratory comparisons (ILC's) in support to EU policies. This report presents the results of an ILC which focussed on the determination of total As, Cd, Cu, Pb, and Hg, as well as extractable Cd and Pb in mineral feed according to Directive 2002/32/EC of the European Parliament and of the Council on undesirable substances in animal feed.
The test material used in this exercise was the Certified Reference Material (CRM) BCR-032 (Moroccan phosphate rock) from the IRMM. The material was relabelled and each participant received one bottle containing approximately 100 g of test material. Fifty-six laboratories from 26 countries registered to the exercise and 51 of them reported results.
Total As, Cd, Cu and Hg were certified in BCR-032 in 1979. The material was re-analysed by two expert laboratories and As an Cd values could be confirmed. Copper could not be analysed in time by an expert laboratory, and thus it was decided to use the indicative value from the certificate as assigned value. The assigned values for total Hg and total Pb were determined at IRMM by a primary method. The same method was used to determine extractable Cd and Pb, whose mass fractions appeared to be identical to the respective total mass fractions and thus the same assigned values were used.
The standard deviation for proficiency assessment was set at 11 % for total As, 10 % for total and extractable Cd, 9 % for total Cu, and at 15 % for total Hg based on the modified Horwitz equation and/or the outcome of previous ILCs organised by IMEP. For total and extractable Pb, was set at 25 %.
The majority of the laboratories reported uncertainties with their results and were rated with z- and ζ-scores (zeta-scores) in accordance with ISO 13528. Performances appear to be good for total & extractable Cd and total & extractable Pb, the percentage of satisfying z-scores ranging between 85 % and 89 %. Share of satisfactory z-scores are significantly lower for total As (61 %), Cu (67 %) and in particular for Hg (47 %). No distinct reason could be given, but it seems altogether that the analytical methods were not always adjusted to the inorganic test material, reflected by some influence of applied technique and inappropriate choice of reference material.JRC.DG.D.6-Food Safety and Qualit
IMEP-111: Total Cadmium, Lead, Arsenic, Mercury and Copper and Extractable Cadmium and Lead in Mineral Feed - Report of the Eleventh Interlaboratory Comparison Organised by the European Union Reference Laboratory for Heavy Metals in Feed and Food
The Institute for Reference Materials and Measurements (IRMM) of the Joint Research Centre, a Directorate-General of the European Commission, operates the European Union Reference Laboratory for Heavy Metals in Feed and Food (EU-RL-HM). One of its core tasks is to organize interlaboratory comparisons (ILCs) among appointed National Reference Laboratories. This report presents the results of the eleventh proficiency test (PT) of the EU-RL-HM which focused on the determination of total Cd, Pb, As, Hg and Cu and extractable Cd and Pb in mineral feed according to Directive 2002/32/EC of the European Parliament and of the Council on undesirable substances in animal feed.
The test material used in this exercise was the Certified Reference Material (CRM) BCR-032, Moroccan phosphate rock. The material was relabelled to prevent identification by the participants and was dispatched the second half of October 2010. Each participant received one bottle containing approximately 100 g of test material. Thirty-one laboratories from 26 countries registered to the exercise of which 28 reported results for total Cd and total Pb, 25 for total Hg and total Cu, 23 for total As and for extractable Cd and extractable Pb. The assigned values (Xref) for total Cd, As and Cu are the indicative values taken from the BCR-032 certificate. The assigned values (Xref) for total Pb, total Hg and for extractable Cd and Pb were provided by IRMM using isotope dilution-inductively coupled plasma-mass spectrometry (ID-ICP-MS).
For total Cd, As, Hg and Cu and for extractable Cd, the uncertainty of the assigned values (uref) was calculated by combining the uncertainty of the characterization (uchar) and a contribution for between-bottle homogeneity (ubb) (which was calculated from the certification report). For total and extractable Pb the number of replicates performed to establish the assigned value was higher (11 replicates) than for the other measurands (6 replicates). Since the aliquots were taken from different bottles, it was assumed that uchar included a contribution for the homogeneity. For total Cd, As and Cu, uchar were taken from the CRM certificate as indicated by the producer. For extractable Cd the same uchar as for total Cd was used. For total Pb and Hg and for extractable Pb, uchar was calculated according to the ISO Guide for the Expression of Uncertainty in Measurement (GUM). Participants were invited to report the uncertainties of their measurements. This was done by the majority of the laboratories taking part in this exercise.JRC.DG.D.6-Food Safety and Qualit
Report of the Eighth Interlaboratory Comparison organised by the Community Reference Laboratory for Heavy Metals in Feed and Food - Total Cd, Pb, As, Hg and Sn and extractable Cd and Pb in Feed of Plant Origin
The Institute for Reference Materials and Measurements (IRMM)of the Joint Research Centre, a Directorate General of the European Commission, operates the Community Reference Laboratory for Heavy Metals in Feed and Food (CRL-HM). One of its core tasks is to organise interlaboratory comparisons (ILCs) among appointed National Reference Laboratories (NRLs). This report presents the results of the eighth ILC of the CRL-HM which focused on the determination of total Cd, Pb, As, Hg and Sn and extractable amounts of Cd and Pb in feed of plant origin following Directive 2002/32/EC of the European Parliament and of the Council on undesirable substances in animal feed.
The test material used in this exercise was a candidate reference material, the matrix being rye grass. The material was relabelled and dispatched to the participants on the second half of October 2009. Each participant received approximately 10 g of test material. Thirty participants from 25 member states registered to the exercise of which 27 reported results for total Cd, Pb and Hg, 23 for extractable Pb, 22 for extractable Cd and for total As and 16 for total Sn. One laboratory did not report results due to a breakdown of the instrumentation, and one laboratory reported results only for Hg for the same reason.
The assigned values (Xref) for total Cd, Pb, As, Hg and Sn were the candidate certified values as obtained during the certification. The assigned values for extractable Cd and Pb were provided by IRMM using isotope dilution-inductively coupled plass-mass spectrometry (ID-ICP-MS).
Participants were invited to report the uncertainty of their measurements, which was provided by the majority of them. The laboratory performance was evaluated using z- end zeta-scores in accordance with ISO 13528. The standard deviation for proficiency assessment (also called target standard deviation), was fixed to 15% of the assigned values for all measurands on the basis of the outcome of previous ILCs organis.JRC.DDG.D.6-Food Safety and Qualit
Mass and ionic composition of atmospheric fine particles over Belgium and their relation with gaseous air pollutants
Original article can be found at: http://www.rsc.org/publishing/journals/EM/Index.asp Copyright Royal Society of Chemistry. DOI: 10.1039/b805157gMass, major ionic components (MICs) of PM2.5, and related gaseous pollutants (SO2, NOx, NH3, HNO2, and HNO3) were monitored over six locations of different anthropogenic influence (industrial, urban, suburban, and rural) in Belgium. SO42-, NO3- NH4+, and Na+ were the primary ions of PM2.5 with averages diurnal concentrations ranging from 0.4-4.5, 0.3-7.6, 0.9-4.9, and 0.4-1.2 g/m3, respectively. MICs formed 39% of PM2.5 on an average, but it could reach up to 80-98 %. The SO2, NO, NO2, HNO2, and HNO3 levels showed high seasonal and site-specific fluctuations. The NH3 levels were similar over all the sites (2-6 g/m3), indicating its relation to the evenly distributed animal husbandry activities. The sulfur and nitrogen oxidation ratios for PM2.5 point towards a low-to-moderate formation of secondary sulfate and nitrate aerosols over five cities/towns, but their fairly intensive formation at the rural Wingene. Cluster analysis revealed the association of three groups of compounds in PM2.5; (i) NH4NO3, KNO3; (ii) Na2SO4; and (iii) MgCl2, CaCl2, MgF2, CaF2, corresponding to anthropogenic, sea-salt, and mixed (sea-salt + anthropogenic) aerosols, respectively. The neutralization and cation-to-anion ratios indicate that MICs of PM2.5 appeared mostly as (NH4)2SO4 and NH4NO3 salts. Sea-salt input was maximal during winter reaching up to 12 % of PM2.5. The overall average Cl-loss for sea-salt particles of PM2.5 at the six sites varied between 69 and 96 % with an average of 87 %. Principal component analysis revealed vehicular emission, coal/wood burning and animal farming as the dominating sources for the ionic components of PM2.5.Peer reviewe
Efficient separation of acetate and formate by ion chromatography: application to air samples in a cultural heritage environment
Girard Thibaut. Cabinet Alain Bensoussan, L'archivage électronique des documents, 1992. In: La Gazette des archives, n°164, 1994. p. 73