Steinborn Angelika, Alder Lutz, Spitzke Madeleine, Dörk Daniela, Anastassiades Michelangelo
Federal Institute for Risk Assessment , Department of Pesticides Safety, Max-Dohrn-Strasse 8-10, 10589 Berlin, Germany.
Federal Office of Consumer Protection and Food Safety (BVL), National Reference Laboratories for Pesticide Residues , Diedersdorfer Weg 1, 12277 Berlin, Germany.
J Agric Food Chem. 2017 Feb 15;65(6):1296-1305. doi: 10.1021/acs.jafc.6b05407. Epub 2017 Feb 7.
An analytical procedure was developed allowing the simultaneous determination of acidic pesticides and their conjugates by addition of an alkaline hydrolysis step into the European Union (EU) version of the QuEChERS method. The procedure resulted additionally in hydrolysis of most esters of phenoxy acids. On the basis of information from metabolism studies and the hydrolytic conditions employed in supervised field trials as well as results on the influence of physical and chemical parameters (temperature, time, type of solvent, type of matrix), alkaline hydrolysis for 30 min at 40 °C was deemed a good compromise for the determination of residues of 2,4-D, dichlorprop, fluazifop, haloxyfop, MCPA, and MCPB. The applicability of the proposed method was tested by analyzing food samples with incurred residues in six German laboratories not involved in method development. Up to 6 times higher residues are measured by using the QuEChERS extraction procedure with the newly developed alkaline hydrolysis step.
通过在欧盟版的QuEChERS方法中加入碱性水解步骤，开发了一种分析方法，可同时测定酸性农药及其共轭物。该方法还导致大多数苯氧酸酯发生水解。根据代谢研究的信息、监督田间试验中采用的水解条件以及物理和化学参数（温度、时间、溶剂类型、基质类型）的影响结果，40℃碱性水解30分钟被认为是测定2,4-D、二氯丙酸、氟吡甲禾灵、高效氟吡甲禾灵、灭草灵和麦草畏残留量的良好折衷方案。六个未参与方法开发的德国实验室通过分析含有残留量的食品样品，对所提出方法的适用性进行了测试。采用新开发的碱性水解步骤的QuEChERS提取程序测量的残留量高达原来的6倍。
