title: Determination and study on dissipation and residue determination of cyhalofop-butyl and its metabolite using HPLC-MS/MS in a rice ecosystem.
abstract: Cyhalofop-butyl is an aryloxyphenoxypropionate postemergence herbicide with good control of barnyard grass in rice paddies. In this study, method for the determination of cyhalofop-butyl and its metabolite was developed with high-performance liquid chromatography tandem mass spectrometry. Dissipation and residue levels of cyhalofop-butyl and its metabolite in rice ecosystems were also investigated. Recoveries and relative standard deviations of cyhalofop-butyl and cyhalofop acid in six matrices at three spiking levels ranged from 76.1 to 107.5% and 1.1 to 8.2%, respectively. The limit of quantitation (LOQ) of cyhalofop-butyl and cyhalofop acid was 0.01 mg/kg in paddy water, paddy soil, rice plant, rice straw, rice hulls, and husked rice. For field experiments, the results showed that cyhalofop-butyl degraded to cyhalofop acid quickly, and the half-lives of cyhalofop acid in paddy water, paddy soil, and rice plant were 1.01-1.53, 0.88-0.97, and 2.09-2.42 days, respectively. Ultimate residues of cyhalofop-butyl and its metabolite in the rice samples were not detectable or below 0.01 mg/kg at harvest.
authors.affiliation: College of Science, China Agricultural University, Beijing, 100193, People's Republic of China.
authors.forename: Junxue
authors.initials: J
authors.lastname: Wu
authors.forename: Kai
authors.initials: K
authors.lastname: Wang
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhang
authors.forename: Hongyan
authors.initials: H
authors.lastname: Zhang
mesh_terms: D002073:Butanes / Q000032:analysis* / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D002853:Chromatography, Liquid; D017753:Ecosystem; D004784:Environmental Monitoring; D006207:Half-Life; D006540:Herbicides / Q000032:analysis / Q000378:metabolism; D013058:Mass Spectrometry; D009570:Nitriles / Q000032:analysis* / Q000378:metabolism; D012275:Oryza / Q000737:chemistry* / Q000378:metabolism; D010573:Pesticide Residues / Q000032:analysis* / Q000378:metabolism; D011422:Propionates; D012987:Soil; D053719:Tandem Mass Spectrometry
chemical_list: D002073:Butanes; D006540:Herbicides; D009570:Nitriles; D010573:Pesticide Residues; D011422:Propionates; D012987:Soil; C543406:cyhalofop-acid; C501583:cyhalofop-butyl