title: Residues of thiamethoxam and chlorantraniliprole in rice grain.
abstract: Thiamethoxam and chlorantraniliprole insecticides have been important tools for controlling pests in rice. However, food safety issues related to pesticide residues are important to consider with a food crop such as rice. Therefore, the objective of this study was to analyze thiamethoxam and chlorantraniliprole residues in rice hull, bran, and polished rice grains. The study was conducted during the 2012 cropping season at the Texas A&M Agrilife Research, David R. Wintermann Rice Research Station, near Eagle Lake, TX, USA. Rice was planted on May 5, 2012, using the cultivar 'Presidio'. Pesticide applications were performed at 5, 15, 25, and 35 days after flowering (DAF) using 1 and 2 times the recommended rate of 30 g active ingredient (ai) ha(-1) for thiamethoxam and 30 g ai ha(-1) for chlorantraniliprole. Sequentially, two treatments using the insecticides at recommended rate were applied at 5 and 25 DAF and at 5, 25, and 35 DAF. Insecticide residues were analyzed in different sample fractions: rice hull, bran, and polished rice grains. The samples were subjected to extraction using an accelerated solvent extraction (ASE) technique. Sample aliquots were analyzed using ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), with a limit of quantification (LOQ) of 5 × 10(-5) mg kg(-1). Residues of thiamethoxam and chlorantraniliprole were detected in rice hull, bran, and polished rice grains, and the quantified values were greater in hull and in rice bran.
authors.affiliation: Research Group in Irrigated Rice, Department of Plant Science, Universidade Federal de Santa Maria (UFSM) , Santa Maria, Rio Grande do Sul, 97105-900, Brazil.
authors.forename: Gustavo Mack
authors.initials: GM
authors.lastname: Teló
authors.forename: Scott Allen
authors.initials: SA
authors.lastname: Senseman
authors.forename: Enio
authors.initials: E
authors.lastname: Marchesan
authors.forename: Edinalvo Rabaioli
authors.initials: ER
authors.lastname: Camargo
authors.forename: Trevor
authors.initials: T
authors.lastname: Jones
authors.forename: Garry
authors.initials: G
authors.lastname: McCauley
mesh_terms: D059022:Food Safety; D007306:Insecticides / Q000032:analysis*; D000073943:Neonicotinoids; D009574:Nitro Compounds / Q000032:analysis*; D012275:Oryza / Q000737:chemistry*; D010078:Oxazines / Q000032:analysis*; D010573:Pesticide Residues / Q000032:analysis*; D000077922:Thiamethoxam; D013844:Thiazoles / Q000032:analysis*; D014481:United States; D062367:ortho-Aminobenzoates / Q000032:analysis*
chemical_list: D007306:Insecticides; D000073943:Neonicotinoids; D009574:Nitro Compounds; D010078:Oxazines; D010573:Pesticide Residues; D013844:Thiazoles; D062367:ortho-Aminobenzoates; C517733:chlorantranilipole; D000077922:Thiamethoxam
keywords: Oryza sativa L.; accelerated solvent extraction; polished rice grains; rice bran; rice hull