Residue and dissipation kinetics of thiamethoxam in a vegetable-field ecosystem using QuEChERS methodology combined with HPLC-DAD.
The dissipation kinetics and residual levels of thiamethoxam in potato and soil under field ecosystem were determined using a QuEChERS method with HPLC-DAD. At fortification levels of 0.05, 0.1, 0.25, 0.5, 1.0 and 5.0 mg kg(-1), it was shown recovery was 99.4% (95.3-103.5%) for potato tubers, and 88.5% (86-91%) for soil with coefficient variation of the method (CV%) was less than 4% in potato tubers, and in soil less than 11%. For repeatability ranged from 1.27% to 4.77%. The LOD and LOQ were estimated to be 0.02 and 0.06 mg kg(-1), respectively. The half-lives were 2.92 and 1.4 days, respectively. The terminal residues of thiamethoxam were below the maximum residue limit (MRL 0.2 mg kg(-1)) after 6 days, which considered to be safe for human beings. These results contribute to establishing the scientific basis of the dosage of thiamethoxam for use in vegetable-field ecosystems.
Biochemistry Department, College of Science, King Saud University, PO Box, 2455, Riyadh 11451, Saudi Arabia; Pesticides Residue and Environmental Pollution Department, Central Agricultural Pesticides Laboratory, Agriculture Research Center, Dokki, Giza 12618, Egypt. Electronic address: drsherif_hussein@yahoo.com.
Sherif H
SH
Abd-Alrahman
D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D017753:Ecosystem; D007700:Kinetics; D000073943:Neonicotinoids; D009574:Nitro Compounds / Q000032:analysis*; D010078:Oxazines / Q000032:analysis*; D010573:Pesticide Residues / Q000032:analysis*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis; D011198:Solanum tuberosum / Q000737:chemistry*; D000077922:Thiamethoxam; D013844:Thiazoles / Q000032:analysis*
D000073943:Neonicotinoids; D009574:Nitro Compounds; D010078:Oxazines; D010573:Pesticide Residues; D012987:Soil; D012989:Soil Pollutants; D013844:Thiazoles; D000077922:Thiamethoxam
Dissipation; HPLC; Kinetics; Potato; QuEChERS; Thiamethoxam