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International comparability of chemical measurements


Specific Objectives
- To provide field laboratories with the possibility to compare their results for chemical amount measurements in important chemical matrices with anchor values (SI-traceable reference values). Participants can compare their data in an international perspective and with full confidentiality.
- To focus particularly on EU Candidate Countries, by providing them free participation in IMEP, training courses and training opportunities as well as guided improvement activities.
Planned Deliverables
- Independent tool to provide result oriented evaluation of measurement capability especially where the Commission tries to bring Member State laboratories (and those of Candidate Countries) up to a common performance level (e.g. acquis communautaire issue, customs laboratories, food control laboratories, environmental control laboratories);
- Completion of the comparison IMEP-17 (human serum), IMEP-18 (S in diesel) and IMEP-19 (metals in rice;)
- Training Candidate Country scientists;
- Sponsored seminars and workshops in Candidate Countries;
- Status reports Metrology in Chemistry for Candidate Countries;
- Network to build a structured system for chemical measurements.

Summary of deliverables made by: 31/12/2001
The International Measurement Programme is an independent tool to provide result oriented evaluation of measurement capability - a prerequisite for building a common measurement system

IMEP-12 (metals in water) Directive 98/83/EC MS water labs;
The measurement of various elements in water has important health and environmental implications.
380 samples and pertinent documentation was sent out to the participants with reference values available for all 10 element. Results were received from 346 participants and all the data was inserted in the IMEP-12 database and thereafter confirmed by the participants. The IMEP-12 certification report was finalised and the certificate was distributed to the participants. The comparisons of results are proceeding on schedule. More than 91 EA nominated laboratories registered for IMEP-12 participation and 85 laboratories have reported results.

IMEP-16 (lead in wine) Reg. 390-2676 BIPM-CCQM, EA, EUROMET, MS food labs;
The ability to measure lead in wine is an important issue for food safety and international trade.

Results were received from 129 laboratories and the participants received their certificates. Graph production and the evaluation of the questionnaire were carried out and the data were presented at the International Wine Federation (OIV) meeting in Paris (March 2001). The participants' report was finalised as well as the evaluation of the questionnaire and graph production. Interaction with OIV has led to follow up action in which the wine sector will orient its measurement system more in line with international best practice.

IMEP-17 (human serum) Directive 98/79/EC DG SANCO, BIPM-CCQM, EA, EUROMET and MS labs in clinical sector.
Laboratories ability to measure metals in human serum is important for the health care sector.
Both unmodified and a modified human serum materials were prepared, stored at -80ºC and are now available at IRMM. The certification work for the 20 parameters under investigation was divided over 12 reference laboratories. The frozen samples were distributed as dry ice cooled parcels to 10 of the reference laboratories. The serum samples were sent to all reference laboratories. All certification laboratories reported reference measurements and the results for all compounds agree very well. An information package was prepared and distributed to the participants.

IMEP-19 (Cd in Rice) DG TRADE, DG SANCO, BIPM-CCQM, EA, EUROMET, MS labs in Food Safety
The ability to measure cadmium and zinc in rice has important health/nutritional and environmental implications.
It was decided to include Zn as a second element of nutritional interest in the CCQM study so Cd, Zn, Cu and Pb will all be certified for the IMEP-19 round at IRMM. It was agreed to use the rice samples for the preparation of a rice IRMM-CRM. Rebottling, labelling and storage of the samples in 15g units was carried out. The water content and water activity were measured as well as the micro-homogeneity for Cd and Zn. Tests on multiple spiking for ICP-MS certification were carried out and preliminary measurements of the Zn content in the rice were carried out using ko-NAA. The water content and hygroscopicity (moisture pickup) of the rice were thoroughly investigated and as a consequence a method for dry-mass correction will be prescribed to all IMEP-19 participants. Certification measurements for Cd, Pb and Cu using ID-ICP-MS and Zn certification measurements using k0-NAA were conducted. The same rice sample is being used for CCQM K24/CCQM P29/EUROMET 565 comparisons, which are presently ongoing. Samples and information packages were sent to the CCQM/EUROMET participants.

Kick-off Seminar Metrology in Chemistry for Candidate Countries (February 2002)
A high impact Candidate Country seminar was organised at IRMM. 50 participants from 12 different Candidate Countries attended. Delegations from accreditation, metrology and education were also there. Very intense discussions took place as well as agreements on follow up actions. Contacts will be used for a further follow up of this fruitful initiative.

Documenting the status of Metrology in Chemistry in Candidate Countries
Participative improvement activity started by the drafting of Status Reports for Metrology in Chemistry for Slovenia, Poland, Estonia, Lithuania (all completed), Slovak Rep., Bulgaria and Cyprus (in progress). In this exercise, all major stakeholders are contacted and join in documenting the present status.

Secondment of NMI staff and fellowships for Candidate Countries
In 2001, Dr N Majcen (Slovenia), Dr E Vassileva (Bulgaria), Dr E Bulska (Poland), Dr I. Leito (Estonia), stayed at IRMM in the framework of the Status Report Metrology in Chemistry. Furthermore, I. Tresl (Czech Rep.) started a category-20 fellowship.

Free participation in IMEP rounds for Candidate Countries
For IMEP-14, 66 Candidate Country laboratories (from 8 countries), for IMEP-16, 63 laboratories (from 11 countries) and for IMEP-12 155 laboratories (from 11 countries) participated (free of charge) in the IMEP rounds.

Setting up an IMEP website, sponsoring conferences and organising training
An IMEP website was set up ( to facilitate information exchange particularly with Candidate Countries. Sponsorship (including the participation of IRMM staff) was given to:
- The 12th Symposium "Spectroscopy in Theory and Practice (Slovenia);
- Sinaia (Romania) training seminar
- Int. Metrology Conference (Romania);
- Isotope Odyssey (Zakopane, Poland);
- high level training sessions on MiC (Maribor, Slovenia)
- Bulgarian National Chemistry Congress;
- Polish Chemical Society; meeting of Bulgarian IMEP participants.

Output Indicators and Impact
- Accession and Mediterranean States: focus on the determination of the ability of Member and Candidate Countries to implement and monitor Community legislation in the food and environmental sector by establishing the degree of international measurement equivalence achieved by reference and field laboratories (e. g. for important compounds in clinical materials, environmental and food measurements);
- European Accreditation: establishing a strategic collaboration with European Accreditation which has the ultimate responsibility for achieving a proper quality for chemical measurements in field laboratories;
- Metrology in Chemistry (MiC): Advice to DGs and public authorities: support to the Candidate Countries (through the network) and to build up a structured measurement system in chemistry.
Summary of the project

IRMM plays a major role in assessing the degree of (international) equivalence of chemical measurements - even on a global scale ¡V via it's International Measurement Evaluation Programme (IMEP) which contributes substantially to the BIPM and EUROMET programmes. IRMMs IMEP programme; in existence since 1989, is internationally acknowledged in this context as the tool to allow result oriented evaluation of chemical measurements, underpinned by undisputed metrologically established values. Such an independent and objective evaluation will especially be useful in the evaluation of the performance of chemical measurements in accession states and with non-EU trade partners (in Asia, the Americas and Australia). The content of this programme is supported by EU policies. Most of the IMEP rounds have the status of a BIPM or EUROMET Key Comparison or Study, which demonstrates the global/European interest in these activities. This corresponds also to the role of IRMM as signatory of the Mutual Recognition Arrangement (between 39 Metrology Institutes including JRC-IRMM under the auspices of BIPM). The various IMEP programmes running at present are documented under the "Summary of 2001 Deliverables" section.


The assessment of the degree of (international) equivalence in chemical measurements is of prime importance because it will form the basic input for any structured (metrological) measurement system to be built up under the auspices of international organisations like BIPM (being endowed with the legal mandate), EUROMET, EURACHEM , CITAC and EA . There is an underlying need to improve the quality of chemical measurements and for the European Commission (represented by IRMM) to provide leadership and co-ordination in this task (see Metrology in Chemistry, B. King, 1998, EUR 19074 EN, p7). To achieve this mandate, the IRMM has the largest isotope mass spectrometry infrastructure in Europe (ThI/EI-MS, ICP-MS) alongside an ultra-clean chemical laboratory (class 5, 120 m², 16 work places, with corrosion resistant construction) and is the world's number one provider of Isotopic Reference Materials.


Institute for Reference Materials and Measurements
B-2440 Geel