School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing, China.
College of Chemistry and Environmental Science, Hebei University, Baoding, China.
J Sci Food Agric. 2021 Sep;101(12):4900-4906. doi: 10.1002/jsfa.11133. Epub 2021 Apr 22.
Wheat is one of the most important cereal crops worldwide, and use of fungicides is an essential part of wheat production. Both prothioconazole and fluoxastrobin give excellent control of important seed and soilborne pathogens. The combination of these two fungicides shows a complementary mode of action and has a wide usage around the world. But the residue levels of these fungicides in the wheat matrix are still unknown.
In the current study, a simple, low-cost and highly sensitive method using modified QuECHERS procedure combined with high-performance liquid chromatography-tandem mass spectrometry was developed to simultaneously quantify E- and Z-fluoxastrobin and the main metabolite prothioconazole-desthio of prothioconazole in the wheat matrix. The recoveries of prothioconazole-desthio, E-fluoxastrobin and Z-fluoxastrobin ranged from 84% to 101%, with relative standard deviation of less than 13.2%. The terminal residues of prothioconazole-desthio and E- and Z-fluoxastrobin were studied in wheat grain and straw under field conditions. The results showed that the terminal residue of the target compounds ranged from <0.01 to 0.029 mg kg and <0.05 to 7.6 mg kg in wheat grain and straw (expressed as dry weight), respectively. The risk quotients of prothioconazole-desthio and fluoxastrobin were 0.2% and 3.2%.
The residue levels of the target analytes in wheat grain were lower than the maximum residue limits recommended by the Chinese Ministry of Agriculture. And the calculated risk quotient values were far below 100%, indicating a low dietary intake health risk to consumers. © 2021 Society of Chemical Industry.
小麦是全球最重要的谷物作物之一，使用杀菌剂是小麦生产的重要组成部分。丙硫菌唑和氟环唑都能极好地防治重要的种传和土传病原菌。这两种杀菌剂的组合具有互补的作用模式，在全世界都有广泛的应用。但是，这些杀菌剂在小麦基质中的残留水平仍不清楚。
在本研究中，开发了一种简单、低成本和高灵敏度的方法，使用改良的 QuECHERS 程序结合高效液相色谱-串联质谱法，同时定量测定小麦基质中的 E-和 Z-氟环唑和丙硫菌唑的主要代谢物丙硫菌唑-脱巯基。丙硫菌唑-脱巯基、E-氟环唑和 Z-氟环唑的回收率在 84%至 101%之间，相对标准偏差小于 13.2%。在田间条件下研究了丙硫菌唑-脱巯基和 E-和 Z-氟环唑在小麦籽粒和秸秆中的最终残留情况。结果表明，目标化合物在小麦籽粒和秸秆中的最终残留量分别为<0.01 至 0.029 mg/kg 和<0.05 至 7.6 mg/kg（以干重计）。丙硫菌唑-脱巯基和氟环唑的风险商数分别为 0.2%和 3.2%。
小麦籽粒中目标分析物的残留水平低于中国农业部推荐的最大残留限量。计算得到的风险商值远低于 100%，表明对消费者的膳食摄入健康风险较低。© 2021 英国化学学会。
