Tianjin Agricultural University, Tianjin 300380, PR China.
Ecotoxicol Environ Saf. 2012 Dec;86:73-8. doi: 10.1016/j.ecoenv.2012.08.029. Epub 2012 Oct 15.
The degradation behavior of metaflumizone was studied in a rice field ecosystem, and a simple and reliable analytical method was developed for determination of metaflumizone in soil, rice straw, paddy water and brown rice. Metaflumizone residues were extracted from samples with acetonitrile. The extract was cleaned up with QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method, and determined by liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). The average recoveries of metaflumizone were 75.2-105.1 percent from soil, rice straw, paddy water and brown rice. The relative standard deviations were less than 15 percent. The limits of quantitation (LOQs) of metaflumizone were 3.0μg/L for paddy water and 3.0μg/kg for other samples. The results of the kinetic study of metaflumizone residue showed that metaflumizone degradation in soil, water and rice straw coincided with C=0.08564e(-0.0505t), C=0.04984e(-0.1982t), C=2.2572e(-0.1533t), respectively; the half-lives were about 13.7d, 3.5d, and 4.5d, respectively. The final residues of metaflumizone on brown rice were lower than maximum residue limit (MRL) of 0.05mg/kg after 28d Pre-Harvest Interval (PHI) at the recommended dosage. Therefore, a dosage of 450mLa.i.ha(-1) with 28 days before harvest was recommended, which could be considered as safe to human beings and animals.
在稻田生态系统中研究了唑虫酰胺的降解行为，并建立了一种简单可靠的分析方法，用于测定土壤、稻草、稻田水和糙米中的唑虫酰胺。唑虫酰胺残留用乙腈从样品中提取。提取物用 QuEChERS（快速、简便、廉价、有效、坚固和安全）方法净化，并用液相色谱-电喷雾串联质谱法（LC-ESI-MS/MS）测定。唑虫酰胺在土壤、稻草、稻田水和糙米中的平均回收率为 75.2-105.1%。相对标准偏差小于 15%。唑虫酰胺的定量限（LOQ）为稻田水 3.0μg/L，其他样品 3.0μg/kg。唑虫酰胺残留的动力学研究结果表明，唑虫酰胺在土壤、水和稻草中的降解符合 C=0.08564e(-0.0505t)、C=0.04984e(-0.1982t)、C=2.2572e(-0.1533t)，半衰期分别约为 13.7d、3.5d 和 4.5d。在推荐剂量下，施药后 28 天预收获间隔（PHI）时，糙米上的唑虫酰胺最终残留量低于 0.05mg/kg 的最大残留限量（MRL）。因此，推荐使用 450mLa.i.ha(-1)的剂量，施药后 28 天收获，这对人类和动物是安全的。
