Dynamic behaviour and residual pattern of thiamethoxam and its metabolite clothianidin in Swiss chard using liquid chromatography-tandem mass spectrometry

Rahman M. M., Farha W., Abd El-Aty A. M. A., Kabir M. H., Im S. J., Jung D., ...Daha Fazla

FOOD CHEMISTRY, cilt.174, ss.248-255, 2015 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 174
  • Basım Tarihi: 2015
  • Doi Numarası: 10.1016/j.foodchem.2014.11.052
  • Dergi Adı: FOOD CHEMISTRY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.248-255
  • Anahtar Kelimeler: Thiamethoxam, Metabolite, Clothianidin, Swiss chard, LC/MS/MS, Dissipation, Half-life, PESTICIDE-RESIDUES, SAMPLE PREPARATION, DISSIPATION, VEGETABLES, EXTRACTION, PLANTS
  • Atatürk Üniversitesi Adresli: Hayır

Özet

A simultaneous method was developed to analyse thiamethoxam and its metabolite clothianidin in Swiss chard using tandem mass spectrometry (in the positive electrospray ionisation mode using multiple reaction monitoring mode) to estimate the dissipation pattern and the pre-harvest residue limit (PHRL). Thiamethoxam (10%, WG) was sprayed on Swiss chard grown in two different areas under greenhouse conditions at the recommended dose rate of 10 g/20 L water. Samples were collected randomly up to 14 days post-application, extracted using quick, easy, cheap, effective, rugged, safe (QuEChERS) acetate-buffered method and purified via a dispersive solid phase extraction (d-SPE) procedure. Matrix matched calibration showed good linearity with determination coefficients (R-2) >= 0.998. The limits of detection (LOD) and quantification (LOQ) were 0.007 and 0.02 mg/kg. The method was validated in triplicate at two different spiked concentration levels. Good recoveries (n = 3) of 87.48-105.61% with relative standard deviations (RSDs) < 10 were obtained for both analytes. The rate of disappearance of total thiamethoxam residues in/on Swiss chard was best described by first-order kinetics with half-lives of 6.3 and 4.2 days. We predicted from the PHRL curves that if the residues were <19.21 or 26.98 mg/kg at 10 days before harvest, then total thiamethoxam concentrations would be below the maximum residue limits during harvest. (C) 2014 Elsevier Ltd. All rights reserved.