Successful round robin test for the DIN EN 15768 analysis method

For the first time, the accredited interlaboratory test organizer DRRR (Deutsches Referenzbüro für Ringversuche und Referenzmaterialien) carried out a laboratory comparison RVEP 253201 for drinking water screening analysis using GC-MS according to DIN EN 15768:2015 (GC-MS identification of water leachable organic substances). A migration water spiked with an unknown number of organic substances and a non-spiked blank sample were provided for the analysis. The laboratories were required to identify the spiked substances as well as their semi-quantitative determination in accordance with the specifications of the standard method.

In total, 18 laboratories participated in the round robin test. Only six laboratories (33 %) were able to correctly identify all five added organic substances after liquid-liquid extraction and analysis using GC-MS. With regard to the semi-quantitative estimation, depending on the substance, between seven and 15 of the participants met the comparability criteria (|z-score| ≤ 2).

Laboratory Lommatzsch und Säger successfully completed the proficiency test by correctly identifying all added substances and accurately determining their concentration (|z-score < 1 for all parameters). The positive participation provides the basis for the accreditation of the DIN EN 15768 analysis method for the testing and conformity assessment of materials in contact with drinking water in our laboratory.