False Positive Identification of Pesticides in Food Using the European Standard Method and LC-MS/MS Determination: Examples and Solutions from Routine Applications

The latest standard method for pesticides in food and feed (EN 15662:2018) is now generally used control laboratories. However, routine analyses of the combination hundreds compounds matrices highlighted that false positive identification particular does occur. aim study was to show relevant precedents when thorough investigation necessary make a decision on possibly compliant/non-compliant samples. Examples include pesticide/commodity atrazine-desethyl date seed coffee, mepanipyrim parsley root, myclobutanil white peppercorn, primisulfuron-methyl herb extract, propham elderberry, quinoclamine fennel tebufenpyrad dried ginger. These examples, which were presented first time, indicated criteria some certain matrices, according SANTE/11312/2021 guideline, might fail: general as stable retention time ion ratio could lead an incorrect qualification pesticides. Standard addition useful not only compensating background during mass spectrometric detection under confirmatory analysis, but also process negligible difference observed between analytes interfering matrix compounds.