EU-RL PT 1101: PAHs in food supplements

Proficiency Test on the determination of 4 EU priority PAHs in a food supplement

The European Union Reference Laboratory for Polycyclic Aromatic Hydrocarbons organises a proficiency test on the determination of 4 EU priority PAHs in a food supplement.

The objective of this study is to evaluate the capabilities of official food control laboratories (OCLs) in the determination of 4 EU priority PAHs in food supplements.

Only national reference laboratories (NRLs) for PAHs and EU official food control laboratories (OCLs) can participate in the study.

Participation is admitted to maximum 50 official food control laboratories, which will be accepted in the order of registration.

Participation is free of charge for NRLs for PAHs. The participation fee for other official food control laboratories, which do not have national reference laboratory status, is EUR 250 (two hundred fifty) per registration!

Test material and analytes

The test material is a commercial dry extract of St. John's wort containing the target analytes (see Table 1). One amber glass screw cap vial containing about 15 g of the dry extract of St. John's wort will be sent to the participants in the second half of June 2011. In addition participants will get an ampoule with a solution of the target PAHs with undisclosed analyte content, in, depending on their preference, either ecetonitrile or toluene. A third ampoule with a solution of the target analytes in the preferred solvent, with disclosed analyte content, will be supplied to the participants to allow the participants verifying instrument calibration against an independent standard.

The measurands are the 4 EU priority PAHs as listed in Table 1.

Results have to be reported at least for the contents of the individual analytes as well as for the sum of the four PAHs. All results have to be reported corrected for recovery, and have to be accompanied by the respective measurement uncertainty.

Table 1: the 4 target PAHs

General outline

Participants are requested to perform three independent analyses of the St. John's wort extract and at least one analysis of the standard solution with undisclosed analyte content using a method of their choice. The analyses shall be performed on the same day.

Performance assessment:

The performance of the participants in the determination of 4 EU priority PAHs in a food supplement will be rated by z-scores and zeta-scores.

The standard deviations for proficiency assessment will be derived:
- for all four analytes from the fitness-for-purpose function given in Commission Regulation (EC) No 333/2007 assuming a value of 0.3 μg/kg for the limit of detection

Performance indicators will not be calculated for the standard solutions.

Registration

Registration shall be done via this link

Schedule