Lafay Florent, Daniele Gaëlle, Fieu Maëva, Pelosi Céline, Fritsch Clémentine, Vulliet Emmanuelle
Univ Lyon, CNRS, Université Claude Bernard Lyon 1, Institut Des Sciences Analytiques, UMR 5280, 5 rue de la Doua, 69100, Villeurbanne, France.
INRAe, Avignon Université, UMR EMMAH, 84000, Avignon, France.
Environ Sci Pollut Res Int. 2022 Mar 3. doi: 10.1007/s11356-022-19397-3.
It is essential to monitor pesticides in soils as their presence at trace levels and their bioavailability can induce adverse effects on soil's ecosystems, animals, and human health. In this study, we developed an analytical method for the quantification of traces of multi-class pesticides in soil using liquid chromatography-tandem mass spectrometry. In this way, 31 pesticides were selected, including 12 herbicides, 9 insecticides, and 10 fungicides. Two extraction techniques were first evaluated, namely, the pressurized liquid extraction and the QuEChERS procedure. The latest one was finally selected and optimized, allowing extraction recoveries of 55 to 118%. The role of the chelating agent EDTA, which binds preferentially to soil cations that complex some pesticides, was highlighted. Coupled with liquid chromatography-tandem mass spectrometry, the procedure displayed very high sensitivity, with limits of quantification (LOQ) in the range 0.01-5.5 ng/g. A good linearity (R > 0.992) was observed over two orders of magnitude (LOQ-100 [Formula: see text] LOQ) with good accuracy (80-120%) for all compounds except the two pyrethroids lambda-cyhalothrin and tau-fluvalinate (accuracy comprised between 50 and 175%) and the cyclohexanedione cycloxydim (accuracy < 35%). Good repeatability and reproducibility were also achieved. The method was finally successfully applied to 12 soil samples collected from 3 land-use types. Among the 31-targeted pesticides, 24 were detected at least once, with concentration levels varying from LOQ to 722 ng/g. Many values were below 0.5 ng/g, indicating that the developed method could provide new knowledge on the extremely low residual contents of some pesticides.
监测土壤中的农药至关重要，因为痕量农药的存在及其生物有效性会对土壤生态系统、动物和人类健康产生不利影响。在本研究中，我们开发了一种使用液相色谱 - 串联质谱法定量土壤中多类痕量农药的分析方法。通过这种方法，选择了31种农药，包括12种除草剂、9种杀虫剂和10种杀菌剂。首先评估了两种提取技术，即加压液体萃取和QuEChERS方法。最终选择并优化了后者，其萃取回收率为55%至118%。突出了螯合剂乙二胺四乙酸（EDTA）的作用，它优先与络合某些农药的土壤阳离子结合。与液相色谱 - 串联质谱联用，该方法显示出非常高的灵敏度，定量限（LOQ）在0.01 - 5.5 ng/g范围内。在两个数量级（LOQ - 100 [公式：见正文] LOQ）内观察到良好的线性（R > 0.992），除了两种拟除虫菊酯高效氯氟氰菊酯和氟胺氰菊酯（准确度在50%至175%之间）以及环己二酮烯草酮（准确度 < 35%）外，所有化合物的准确度都很好（80% - 120%）。还实现了良好的重复性和再现性。该方法最终成功应用于从3种土地利用类型采集的12个土壤样品。在31种目标农药中，至少检测到24种，浓度水平从LOQ到722 ng/g不等。许多值低于0.5 ng/g，表明所开发的方法可以提供关于某些农药极低残留量的新知识。
