Patel Badal V, Chawla Suchi, Gor Hetal, Upadhyay Payal, Parmar Kaushik D, Patel Anil R, Shah Paresh G
Pesticide Residue Laboratory, AINP on Pesticide Residues, Anand Agricultural University, Anand, Gujarat, -388110, India.
Environ Sci Pollut Res Int. 2016 Oct;23(20):20871-20881. doi: 10.1007/s11356-016-7331-8. Epub 2016 Aug 3.
A method was validated for estimating fluopyram and tebuconazole in onion on LC-MS/MS using dispersive QuEChERS. Three sprays of a combination fungicide fluopyram + tebuconazole (Luna experience, 400 SC) were applied @ 75 + 75 and 150 + 150 g a.i. ha at an interval of 10 days on onion using Knapsack sprayer. First spray was made at bulb setting stage. Spring onion samples were drawn at 0 (1 h), 1, 3, 5, 7, 10, 15, and 20 days and matured onion bulb at harvest (52 days) after the last spray. Soil samples were also drawn at harvest. Foliar application of the combination product resulted in 1.14 and 2.86 mg kg fluopyram residues on spring onion at standard and double dose, respectively, one hour after the last application. The levels of fluopyram residues gradually declined and recorded 0.25 and 0.58 mg kg on 20th day of application with half-lives of 8.8 and 9.1 days at standard and double dose, respectively. For tebuconazole, the corresponding residues observed after 1 h (0 day) of application were 0.92 and 2.29 mg kg. The levels declined gradually to 0.12 and 0.33 mg kg on 20th days with half-life of 6.7 to 7.7 days at standard and double dose, respectively. Here, we are proposing a pre-harvest interval of 7 day for fluopyram and tebuconazole in spring onion when applied at 75 + 75 g a.i. ha (400 SC). Risk assessment was done by calculating hazard quotient and by comparing theoretical maximum residue intake (TMRI) with maximum permissible intake (MPI). In all the cases, results of the study showed that HQ (Hazard Quotient) ≤1 and TMDI < MPI. Hence, the use of this combination product can be recommended with pre harvest interval of 7 days. The data can be used in establishing MRLs (maximum residue limits) for spring onion after considering multilocation trials.
建立了一种使用分散固相萃取-快速、简便、廉价、有效、耐用、安全（QuEChERS）方法结合液相色谱-串联质谱（LC-MS/MS）测定洋葱中氟吡菌酰胺和戊唑醇的方法。使用背负式喷雾器，以75 + 75克和150 + 150克有效成分/公顷的剂量，间隔10天对洋葱进行三次组合杀菌剂氟吡菌酰胺+戊唑醇（露娜森，400 SC）喷雾处理。第一次喷雾在鳞茎形成期进行。在最后一次喷雾后的0（1小时）、1、3、5、7、10、15和20天采集葱样品，并在收获时（最后一次喷雾后52天）采集成熟洋葱鳞茎。收获时也采集土壤样品。在最后一次施药1小时后，叶面喷施该组合产品，标准剂量和双倍剂量下葱中氟吡菌酰胺残留量分别为1.14和2.86毫克/千克。氟吡菌酰胺残留量逐渐下降，在施药第20天时分别为0.25和0.58毫克/千克，标准剂量和双倍剂量下的半衰期分别为8.8天和9.1天。对于戊唑醇，施药1小时（0天）后观察到的相应残留量为0.92和2.29毫克/千克。在第20天时残留量逐渐下降至0.12和0.33毫克/千克，标准剂量和双倍剂量下的半衰期分别为6.7天和7.7天。在此，我们建议当以75 + 75克有效成分/公顷（400 SC）的剂量施用于葱时，氟吡菌酰胺和戊唑醇的收获前间隔期为7天。通过计算危害商数并将理论最大残留摄入量（TMRI）与最大允许摄入量（MPI）进行比较来进行风险评估。在所有情况下，研究结果表明危害商数（HQ）≤1且理论最大每日摄入量（TMDI）<最大允许摄入量（MPI）。因此，建议使用该组合产品，收获前间隔期为7天。在考虑多地试验后，这些数据可用于确定葱的最大残留限量（MRL）。
