摘要
【目的】研究甲氰菊酯和氰戊菊酯在芥蓝中的消解动态。【方法】通过田间试验和气相色谱(GCECD)检测。【结果】甲氰菊酯和氰戊菊酯在芥蓝和土壤中的消解动态均符合一级动力学方程,甲氰菊酯在芥蓝中的半衰期为0.72～1.6 d,在土壤中为7.2～8.2 d;氰戊菊酯在芥蓝中的半衰期为1.2～4.6 d,在土壤中为6.1～23.4 d,均属于易消解农药。甲氰菊酯乳油和氰戊菊酯乳油分别按最高推荐使用剂量和1.5倍最高推荐使用剂量施药3～4次,距末次施药后5 d,收获的芥蓝中甲氰菊酯的残留量低于1.54 mg/kg,膳食风险评估风险商值(RQ)为0.407;距末次施药后7 d,收获的芥蓝中氰戊菊酯的残留量低于1.14 mg/kg,风险商值为0.452,都处于安全水平。【结论】建议在使用20%甲氰菊酯乳油和20%氰戊菊酯乳油防治芥蓝虫害时,甲氰菊酯用药量为90 g a.i/hm^2,氰戊菊酯为120 g a.i/hm^2,最多施用3次,安全间隔期分别为5 d和7 d。
[Purpose]The aim of this study was to investigate the residue dissipation of fenpropathrin and fenvalerate in Chinese kale and soil under open field conditions.[Method]The methods for determination of fenpropathrin and fenvalerate were developed and validated using GC-ECD,based on which,the dynamics of both two pesticides were investigated via field trials.[Results]The dissipation trends of fenpropathrin and fenvalerate in Chinese kale and soil were fitted to the first order kinetics with half-life of 0.72-1.6d and1.2-4.6d in Chinese kale,and of7.2-8.2d and6.1-23.4d in soil,respectively,both of which belonged to the pesticide that was easy to be degraded.According to the terminal residue results,the fenpropathrin EC and fenvalerate EC were applied at a recommended dosage and at 1.5 times the recommended dosage for3to4times,the residues of fenpropathrin in Chinese kale was lower than1.54mg/kg with a risk quotient(RQ)of 0.407 on 5d after the last application.The residues of fenvalerate was lower than1.14mg/kg with a RQ of0.452on7d after the last application,indicating that the risk was not significant.[Conclusion]Based on the results of risk assessment,it is recommended that20%fenpropathrin EC used at a dose of 90g a.i/hm^2and20%fenvalerate EC used at a dose 120g a.i/hm^2in Chinese kale,the application time do not exceed3times,and the pre-harvest intervals are5d and7d for fenpropathrin and fenvalerate,respectively.
作者
赵欣
邓毅书
浦恩堂
代雪芳
李文希
毛佳
ZHAO Xin;DENG Yishu;PU Entang;DAI Xuefang;LI Wenxi;MAO Jia(College of Resources and Environment,Yunnan Agricultural University, Kunming 650201, China;Institute of Agro-Environmental Resources,Yunnan Agricultural Science, Kunming 650205, China)
出处
《云南农业大学学报（自然科学版）》
CSCD
北大核心
2018年第6期1120-1126,共7页
Journal of Yunnan Agricultural University:Natural Science
基金
云南省科技惠民专项项目(2016RA008)
云南省科技创新人才计划项目(2015HC025)
关键词
甲氰菊酯
氰戊菊酯
芥蓝
残留
膳食风险评估
fenpropathrin
fenvalerate
Chinese kale
residue
dietary intake risk assessment
