Center for Quality Safety and Standard Research of Agricultural Products, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China.
Ecotoxicol Environ Saf. 2012 Oct;84:112-6. doi: 10.1016/j.ecoenv.2012.06.030. Epub 2012 Aug 16.
This study investigates the dissipation and residue of a metalaxyl and dimethomorph mixed formulation in grape and soil. A high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) analytical method was developed to determine the residue of metalaxyl and dimethomorph in grape and soil. The results showed that the average recoveries are in the range of 86.84 percent to 97.30 percent. The dissipation rate of metalaxyl in grape (with half life of 4.9 days) was faster than in soil (with half life of 8.7 days). The dissipation rates of E- and Z-isomers of dimethomorph in grape were almost the same (with half lives of 9.0 and 9.8 days, respectively). However, the dissipation rate of the E-isomer in soil was much faster than that of the Z-isomer (with half lives of 10.3 and 31.5 days, respectively). Moreover, the terminal residue of metalaxyl and dimethomorph were significantly below the available maximum residue limits (MRL). However, a difference was observed between the concentration of the Z- and E-isomers either in grape or soil. The ratio of E-isomer to Z-isomer in grape was higher than in soil, which may due to the different water solubilities and polarities of the two isomers.
本研究调查了金属吖啶和二甲嘧菌胺混剂在葡萄和土壤中的消解和残留情况。建立了高效液相色谱-串联质谱（HPLC-MS/MS）分析方法，用于测定葡萄和土壤中金属吖啶和二甲嘧菌胺的残留量。结果表明，平均回收率在 86.84%至 97.30%之间。金属吖啶在葡萄中的消解速度（半衰期为 4.9 天）快于在土壤中的消解速度（半衰期为 8.7 天）。E-和 Z-异构体二甲嘧菌胺在葡萄中的消解速率几乎相同（半衰期分别为 9.0 和 9.8 天）。然而，E-异构体在土壤中的消解速度远快于 Z-异构体（半衰期分别为 10.3 和 31.5 天）。此外，金属吖啶和二甲嘧菌胺的最终残留量明显低于最大残留限量（MRL）。然而，无论是在葡萄还是土壤中，都观察到 Z-和 E-异构体的浓度存在差异。葡萄中 E-异构体与 Z-异构体的比例高于土壤，这可能是由于两种异构体的水溶性和极性不同。
