European Union Proficiency Tests for pesticide residues in cereals and feedstuff, from 2007 to 2022- Data collection experience

The European Union Reference Laboratory for pesticide residues in cereals and feeding stuff (EURL-CF) has, for 16 consecutive years since 2007, organized European Union Proficiency Tests (EUPTs) for analysis of multiple pesticide residues in various cereals and feedstuff commodities. The EUPTs are directed to National Reference Laboratories (NRLs), and official laboratories (OfLs) in European member (EU) states and in European Free Trade Association (EFTA) countries. The aim of the EUPTs is to gain information regarding the quality, accuracy and comparability of pesticide residue data in cereals and feedstuff reported by different EU and EFTA laboratories, to help evaluate and improve their performance. This article summarizes 16 years’ experience in processing and analyzing results for EUPTs for pesticide residues in cereals and feedstuff. It provides an overview of the performance and development of as many as 160 laboratories throughout the years. Results are highlighted in terms of the number of participants, analytical scope, z scores, false positive and false negative reported results, and classification of laboratories. The performance of laboratories in the EUPTs has improved over time. A notable increase was observed in NRLs and OfLs classified as category A, indicating satisfactory overall performance and scope coverage for the majority of participating laboratories.