title: Spinach or amaranth contains highest residue of metalaxyl, fluazifop-P-butyl, chlorpyrifos, and lambda-cyhalothrin on six leaf vegetables upon open field application.
abstract: To select representative leaf vegetables which may contain the highest residue, field experiments of metalaxyl, fluazifop-P-butyl, chlorpyrifos, and lambda-cyhalothrin on six crops including pakchoi, rape, crown daisy, amaranth, spinach, and lettuce were designed and conducted. In this study, a high-performance liquid chromatograph and electrospray ionization tandem mass spectrometer with multiple reaction monitoring was used to simultaneously determine metalaxyl and fluazifop-P-butyl residue in various samples, and a gas chromatograph with electron capture detector was used to detect chlorpyrifos and lambda-cyhalothrin. The limits of quantification (LOQ) of metalaxyl, fluazifop-P-butyl, chlorpyrifos, and lambda-cyhalothrin were in the range of 0.001-0.01 mg kg(-1) for all samples, and the average recoveries of all pesticides ranged from 67.6 to 119.1% at spiked levels of 0.01-0.1 mg kg(-1). In supervised field trials, the half-lives of metalaxyl, fluazifop-P-butyl, chlorpyrifos, and lambda-cyhalothrin were in the range of 1.11-3.79 days, 1.11-2.27 days, 1.13-5.17 days, and 1.77-6.24 days. It was also found that all pesticide residues in spinach and/or amaranth were higher than others after application. It is recommended that spinach or amaranth can be selected as a representative crop of leaf vegetables in studying systemic fungicide, insecticides, and herbicides with similarity as metalaxyl, fluazifop-P-butyl, chlorpyrifos, and lambda-cyhalothrin.
authors: Department of Applied Chemistry, College of Science, China Agricultural University, Beijing 100193, People's Republic of China.
authors: Sufang
authors: S
authors: Fan
authors: Fengzu
authors: F
authors: Zhang
authors: Kailin
authors: K
authors: Deng
authors: Chuanshan
authors: C
authors: Yu
authors: Shaowen
authors: S
authors: Liu
authors: Pengyue
authors: P
authors: Zhao
authors: Canping
authors: C
authors: Pan
mesh_terms: D000409:Alanine / Q000031:analogs & derivatives / Q000032:analysis; D027721:Amaranthus / Q000737:chemistry*; D002681:China; D004390:Chlorpyrifos / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D009570:Nitriles / Q000032:analysis; D010573:Pesticide Residues / Q000032:analysis*; D018515:Plant Leaves / Q000737:chemistry*; D011722:Pyrethrins / Q000032:analysis; D011725:Pyridines / Q000032:analysis; D021241:Spectrometry, Mass, Electrospray Ionization; D018724:Spinacia oleracea / Q000737:chemistry*
chemical_list: D009570:Nitriles; D010573:Pesticide Residues; D011722:Pyrethrins; D011725:Pyridines; C050585:fluazifop-butyl; C028175:metalaxyl; D004390:Chlorpyrifos; D000409:Alanine; C037304:cyhalothrin