Standardization of methods

At the request of the European Committee for Standardization (CEN, CEN/TC 327) and in close cooperation of the RIKILT - Institute of Food Safety, Wageningen, Netherlands, the Food and Environment Research Agency (FERA), York, UK, and the European Union Reference Laboratory (EU-RL) for Dioxins and PCBs in Feed and Food a standard for determination of PCDD/Fs and PCBs in animal feed was described. In order to validate this new CEN method a ring trial was organized by the RIKILT - Institute of Food Safety to be accomplished within the EU-RL/NRL network as well within the CEN network. The objective was to assess the comparibility of results of all relevant parameters (17 PCDD/F, 12 dioxin-like PCBs and 6 indicator PCBs) obtained by the new draft CEN standard in four samples of animal feed and a standard solution.

In addition to the validation of the CEN method, the available data (including results of laboratories using in-house validated methods) was evaluated for checking of the analytical performance of participating laboratories, in particular NRLs, in a proficiency test.

The evaluation of the data was performed in close cooperation of the RIKILT - Institute of Food Safety and the EU-RL for Dioxins and PCBs in Feed and Food.

Treaty of Lisbon entered into force

On 1 December 2009 the European Community was replaced by the European Union which succeeds it and takes over all its rights and obligations.
As consequence the Community Reference Laboratory for Dioxins and PCBs in Feed and Food was re-named as the

European Union Reference Laboratory (EU-RL) for Dioxins and PCBs in feed and Food.

Results of interlaboratory studies organized by the CRL between 2006 and 2009

The CRL for Dioxins and PCBs in Feed and Food organized five interlaboratory studies and proficiency tests on the determination of PCDD/F and PCB in different food and feed matrices between 2006 and 2009. NRLs for Dioxins and PCBs form EU member states, official and private laboratories participated in these studies. An overview of the results was presented at the 4th International Symposium on Recent Advances in Food Analysis (RAFA) in Pargue.

Proficiency test on determination of PCDD/Fs and PCBs in Canned Sausage (Pork) 2009

The proficiency test on the determination of PCDD/Fs and PCBs in pork sausage was organized by the CRL between January and April 2009. 77 NRLs and official laboratories from EU member states reported results for the requested parameters. Besides the determination of PCDD/Fs and PCBs participants were also asked to report the lipid content of the sample.

Analytical Requirments for Determination of NDL-PCBs

The EU Commission has initiated steps to set maximum levels for non dioxin-like PCBs expressed as sum of the six indicator PCBs (PCB 28, 52, 101, 138, 153 and 180) in certain food samples. Therefore, the CRL was asked to propose criteria for the analytical determination of NDL-PCBs. A working document was discussed at the CRL-NRL workshop, held on November 2008 in Freiburg and presented at the Dioxin conference in Beijing 2009.

Proficiency test on the determination of PCDD/Fs and PCP in guar gum and follow-up analyses

In cooperation with the CRL for Single Residue Methods [CRL-SRM] Stuttgart, Germany, the CRL for Dioxins and PCBs in Feed and Food organized a proficieny test on the determination of PCDD/F, PCB and pentachlorophenol (PCP) in guar gum samples in 2008. Additionally, further tests due to some elevated levels reported in the PT were performed at the CRL focusing on different extraction techniques and solvents. An overview of this PT and the results were presented at the Dioxin conference in Beijing 2009.

Evaluation of Results of Guar Gum PT

In cooperation with the CRL for Single Residue Methods [CRL-SRM] Stuttgart, Germany, the CRL for Dioxins and PCBs in Feed and Food organized a proficienz test on the determination of PCDD/F, PCB and pentachlorophenol (PCP) in guar gum samples. 53 official amd private laboratories worldwide analyzing PCDD/F and PCB using confirmatory and screening methods and 41 laboratories analyzing PCP participated in the Guar Gum PT. The results were discussed at the CRL-NRL workshop in July 2008. A final comprehensive evaluation of the data for all participating laboratories will be available soon.

The guar gum case: Contamination with PCP and dioxins and analytical problems

A summary of the contamination of guar gum with PCDD/F and PCP, actions taken afterwards and resulting analyticla problems was presented at the Dioxin Conference in Birmingham 2008.

Interlaboratory study on the harmonization of extraction procedures

The process of harmonization of extration methods for the determination of PCDD/F in mineral feed, which was initiated with the interlaboratory study on etxraction techniques for sepiolite in 2006, was contionued with an interlaboratory comparison on extraction techniques for fullers earth and mangenese oxide. The results of the interlaboratory study with 23 participating laboratories and additional comprehensive tests at the CRL were presented at the Dioxin conference in Birmingham 2008.

PT on the Determination of PCDD/Fs, PCBs and PCP in Guar Gum

The CRL for Dioxins and PCBs in Feed and Food and the CRL for Single Residue Methods invite interested laboratories to participate in a joint proficiency test on the determination of PCDD/Fs, PCBs and PCP in guar gum samples.

The PT is open for NRLs and official laboratories (OFLs) dealing with PCDD/F, PCB and/or PCP analysis. Additionally the PT is also open for other laboratories analyzing PCDD/F and PCB, only, or PCDD/F, PCB and PCP. More details about the PT can be found in the Announcement Letter.

Recommendations for extraction procedures for PCDD/Fs and PCBs

The CRL for Dioxins and PCBs in Feed and Food organized two interlaboratory studies on extraction techniques of PCDD/F and PCB in 2006 and 2007 for sepiolite, fullers earth and manganese oxides. Conclusions and recommendations derived from these studies were formally adopted at the CRL/NRL workshop on November 5th, 2007.

Harmonization of Extraction Methods for the determination of PCDD/Fs in Sepiolite

The CRL performed a comprehensive study on extraction methods for PCDD/F in sepiolite in 2006, including an interlaboratory stduy withn 17 participating laboratories and further tests at the CRL. The study focused on the different extraction methods and solvents and the pre-treatment of sepiolite before extraction. A summary of the interlaboratory study, the results of the tests at the CRL and conclusions were presented at the Dioxin conference in Tokyo 2007.

Influence of new WHO-TEFs on TEQ-based results of food samples

The existing maximum and action levels are fixed on basis of WHO-TEFs published in 1997. These TEFs were revised in 2005. These changes will be considered at the review of maximum and action levels. In order to contribute to this discussion, the levels of PCDD/Fs and dl-PCBs in 1121 food samples of different matrices collected between 2002 and 2006 were evaluated with both TEF concepts and the results presented at the Dioxin conference in Tokyo 2007.

Contamination of Guar Gum from India with PCP and Dioxins

The Rapid Alert System for Food and Feed (RASFF) of the European Commission received on 24 July 2007 in the evening a notification from the competent authorities of Switzerland concerning a finding of a serious contamination by dioxins and pentachlorophenol in guar gum originating from India.

Harmonization of extraction procedures - Sepiolite

The CRL-NRL workshop was held in Freiburg. The harmonization of extraction procedures for mineral feed additives was one important topic. Therefore an interlaboratory study was organized with NRLs from EU member states and expert laboratories.