Reference materials certified

It is known that the reliability of analytical information obtained depends particularly on the range of reference materials (RM) used. The most of RMs developed by the Institute of Geochemistry, SB RAS are included in the State Register of certified types of National Certified Reference Materials of Russian Federation. The reference materials are routinely analyzed for the stability and their life durations are timely prolonged. Developed RMs (27 samples) characterize mainly mineral substances. 

The analysis was performed by SRXRF at the XRF beam-line of VEPP-3, Institute of Nuclear Physics, Novosibirsk, Russia. For accuracy control the International Certified Reference Materials were used. There were obtained all metrological characteristics, namely precision, accuracy and lower limits of detections. 

NAA is a quantitative method. Quantification can be performed by comparison to standards or by computation from basic principles (parametric analysis). A certified reference material specifically for trace impurities in silicon is not currently available. Since neutron and y rays are penetrating radiations (free from absorption problems, such as those found in X-ray fluorescence), matrix matching between the sample and the comparator standard is not critical. Biological trace impurities standards (e.g., the National Institute of Standards and Technology Standard Rference Material, SRM 1572 Citrus Leaves) can be used as reference materials. For the parametric analysis many instrumental fiictors, such as the neutron flux density and the efficiency of the detector, must be well known. The activation equation can be used to determine concentrations ... 

Many of these are also available as BCS Certified Reference Materials (CRM) supplied by the Bureau of Analysed Samples Ltd, Newham Hall, Middles borough, UK, who also supply EURONORM Certified Reference Materials (ERCM), the composition of which is specified on the basis of results obtained by a number of laboratories within the EEC. BCS Reference Materials are obtainable from the Community Bureau of Reference, Brussels, Belgium. In the USA similar reference materials are supplied by the National Bureau of Standards. 

The following British Chemical Standard or Euronorm Certified Reference Materials may be used for practice in this determination BCS No. 402 ECRM 084-1. 

NIST s first four certified reference materials were steel samples, and these were followed by many others. The program supplied analytically well characterized homogeneous materials. This program included, from the beginning, homogeneity... 

In geochemistry, the introduction of RMs did not take place until 1951 but, once RM usage became a regular part of geochemical analysis, the consequences were not far short of amazing. For many years geochemical analysts had been concerned about the accuracy of their determinations of major elements in rocks, but it was the potential of emission spectrometry for the determination of trace elements which set off the production of the first rock Certified Reference Materials (CRMs),... 

The definition of a certified reference material (CRM) is given in ISO Guide 30 (1992) and it forms the root of all other ISO Guides ... 

Traceability of measurement results is essential in the establishment of a certified reference material. As stipulated in ISO Guides 30 and 35, a certified reference material can only be certified if there is an uncertainty statement with a traceability statement. Basically, traceability means anchoring. In classical analytical chemistry, that SI system is often the best choice as a reference (= anchoring poinf). However, there is a wide range of parameters either defined by a method or defined by the... 

Griepink B, Maier EA, Quevauvilier P and Muntau H (1991) Certified reference materials for the quality control of analysis in the environment. Fresenius Anal Chem 339 599-603. 

ISO Guide 32 (1997) Calibration in analytical chemistry and use of certified reference materials. International Organization for Standardization, Geneva. 

In Wolf WR, ed. Biological Reference Materials, pp. 109-140. John Wiley Sons New York. Okamoto K and Fuwa K (1985) Certified reference material program at the National Institute for Environmental Studies. Anal Sd 1 206-207. 

Qubvauviller Ph (1995) Certified reference materials for specific chemical forms of elements. Analyst 120 597-602. 

Qubvauviller Ph and Maier EA 1999), Interlaboratory Studies and Certified Reference Materials for Environmental Analysis. Elsevier Publishers B.V., Amsterdam. 

Richardson JM (1995) Certified reference materials programme at the Geoscience Laboratories, Sudbury, Ontario, Canada. Analyst 120 1513-1518. 

Willie SN (1997) The preparation of National Research Council Certified Reference Materials. 

Bowman WS (1994) Stream sediment reference materials STSD-i to STSD-4. In Catalogue of Certified Reference Materials, CCRMP 94-iE. Natural Resources Canada, Ottawa. 

Griepink B, Maier EA, Muntau H, Wells DE (1991) Certified reference Materials chlorobiphe-nyls (lUPAC nos 28, 52, loi, 118,153 and 180) in dried sewage sludge - CRM 392. Fresenius J Anal Chem 339 173-180. 

Jenks P, Boekholt a, Maaskant J, Rucinski R (1998) Are Certified Reference Materials a victim of Quality Systems Fresenius J Anal Chem 360 366-369... 

Klich H, Walker R (1993) COMAR-the international database for certified reference materials. Fresenius J Anal Chem 345 104-106. 

Morabito R, Muntau H, Cofino W, Quevauviller Ph 1999) A new mussel certified reference material (CRM 477) for the quality control of butyltin determination in the marine environment. J Environ Monit 1 75-82. 

National Research Coundl Canada (1992) Certified Reference Material NASS-4 Open Ocean Seawater Reference Material for Trace Metals. National Research Council of Canada. Ottawa. National Research Council Canada (1995) Certified Reference Material CARP-i Groimd Whole Carp Reference Material for Organochlorine Compounds. National Research Council of Canada, Ottawa. 

Okamoto K, Iwata Y (1982) Preparation of pond sediment. In Okamoto K, ed. Preparation, Analysis and Certification of Pond Sediment Certified Reference Material. Research Report No. 38, pp 13-22. National Institute for Environmental Studies, Ibaraki. 

Pauwels J. De Angelis L, Grobecker KH (1991) Solid sampling Zeeman atomic absorption spectrometry in production and use of certified reference materials. Pure Appl Chem 63 1199-1204. 

Quevauviller Ph, Kramer KJM, Vinhas T (1996) Certified reference material for the quality control of cadmium, copper, nickel and zinc determination in estuarine water (CRM 505). Fresenius J Anal Chem 354 397-404. 

Quevauviller Ph. Maiee EA, Kramer KJM (1998a) Production of Certified Reference Materials for Pollutants in Environmental Matrices. European Commission Report EUR 18157 N, CCF Academic Press, Tarbes. 

Trace elements in soils and sludges (CRMs 141R-146R 597) pp 225-232 (1998k) Chlorobi-phenyls in sewage sludge (CRM 392) pp 240-243 (1998I) Trimethyl-lead in urban dust (CRM 605) pp 274-278 In Production of Certified Reference Materials for Pollutants in Environmental Matrices. European Commission Report EUR 18157 EN, CCF Academic Press, Tarbes. 

Quevauviller Ph, Maier EA, Vercoutere K, Muntau H, Griepink B (1992a) Certified reference material (CRM 397) for the quality control of trace element analysis of human hair. Fresenius J Anal Chem 343 335-338. 

Quevauviller Ph, Vercoutere K, Griepink B (1992b) Certified reference materials (CRMs 398 and 399) for the quality control of major element determination in freshwater. Mikrochim Acta 108 195-204. 

Yoshinaga j, Morita M, Okamoto K (1997) New human hair certified reference material for methylmercury and trace elements. Fresenius J Anal Chem 357 279-283. 

For the high accuracy needed in the quantitative measmement of the species, quality assurance of the analytical procedures is of prime importance. This can only be achieved by using representative RMs, certified for the relevant species. Up to now the number of existing certified reference materials is very limited. This section will give a survey of the main species that are presently determined routinely or for research purposes. 

Certified reference materials (CRMs) to validate measurements of organic constituents were introduced in the early 1980 s, more than a decade after the development of the first natural matrix CRMs for inorganic constituents. There are three types of CRMs to support measurements of organic constituents ... 

Jacob J, Kaechee W, and Wagstaffe PJ (1984) Polycyclic aromatic compounds of environmental and occupational importance - their occurrence, toxicity and development of high purity certified reference materials. Part I. Fresenius J Anal Chem 317 101-114,... 

Maier EA, Boenke A, and Meriguet P 1997) Importance of the Certified Reference Materials Programme for the European Union. Trends Anal Chem 16 496-503... 

---