Influence of QuEChERS modifications on recovery and matrix effect during the multi-residue pesticide analysis in soil by GC/MS/MS and GC/ECD/NPD

Abstract

A QuEChERS extraction followed by GC/MS/MS and GC-μECD/NPD for 216 pesticide and metabolites determination in soil simultaneously were developed and compared. Volume of water, volume and polarity of solvent, and cleanup sorbents (C18, GCB, PSA) were optimized. The QuEChERS with and without purification step were applied to estimate effectiveness of the method. The recovery and matrix effect (ME) were critical parameters within each tested procedure. The optimal method without cleanup was validated. Accuracy (expressed as recovery), precision (expressed as RSD), linearity, LOQ, and uncertainty were determined. The recoveries at the three spiking levels using matrix-matched standards ranged between 65 and 116% with RSD ≤17 and 60–112% with RSD ≤18% for MS/MS and μEC/NP, respectively. The LOQ ranged from 0.005–0.01 mg/kg for MS/MS to 0.05 mg/kg for μEC/NP. The ME for most of pesticides resulted in enhancement of the signal and depended on the analyte and detection system: MS/MS showed ME from −25 to 74%, while μEC/NP from −45 to 96%. A principal component analysis was performed to explain the relationships between physicochemical parameters and ME of 216 pesticides. The QuEChERS protocol without the cleanup step is a promising option to make the method less expensive and faster. This methodology was applied in routine analysis of 263 soil samples in which p,p’ DDT was the most frequently detected (23.5% of samples) and pendimethalin with the highest concentration (1.63 mg/kg).Electronic supplementary materialThe online version of this article (doi:10.1007/s11356-016-8334-1) contains supplementary material, which is available to authorized users.

Health risk assessment of neonicotinoid insecticide residues in pistachio using a QuEChERS‐based method in combination with HPLC‐UV

“…The main goal in using the QUECHERs based method, is to clean–up the targets compounds by using the most suitable solvent which possesses a greater permeability into the matrix and the adsorbents (C18, GCB, PSA) and the amount of water used (Łozowicka, Rutkowska, & Jankowska, ). These items are significant parameters of QuEChERS that affect the extraction performance and thus have been optimized in this study.…”

“…Because addition of water to the dry sample is important to achieve maximum extraction of the target (Cajka et al, ; Łozowicka et al, ), we included this step during extraction. As presented in Figure , when water was added to the fortified matrix‐matched pistachio sample, the QuEChERS method was more efficient in completing four phases; by contrast, in the absence of water during extraction, only two phases could be completed.…”

“…The main goal in using the QUECHERs based method, is to clean-up the targets compounds by using the most suitable solvent which F I G U R E 1 Chromatograms for the standard mixture of imidacloprid and acetamiprid, respectively, at 1.7 μg/mL concentration level on a C 18 column (250 × 4.6 mm i.d., 5 μm) at 40 C. Experimental conditions: flow rate, 1 mL/min; λ = 254 nm; and isocratic elution with different ratios of acetonitrile:water as a mobile phase: (a) 65:35, (b) 30:70, and (c) 25:75 v/v possesses a greater permeability into the matrix and the adsorbents (C18, GCB, PSA) and the amount of water used (Łozowicka, Rutkowska, & Jankowska, 2017). These items are significant parameters of QuEChERS that affect the extraction performance and thus have been optimized in this study.…”

“…Because addition of water to the dry sample is important to achieve maximum extraction of the target (Cajka et al, 2012;Łozowicka et al, 2017), we included this step during extraction. As presented in The upper layer comprising ACN was expected to contain our targets as ACN has satisfactory efficacy for the extraction of a wide range of pesticides from different matrices.…”

Influence of a Commercial Biological Fungicide containing Trichoderma harzianum Rifai T-22 on Dissipation Kinetics and Degradation of Five Herbicides in Two Types of Soil

“…Propylene containers were closed with a cover one day after chemical spraying and were opened to take samples for GC analysis. The samples for the pesticide analysis were taken after 1,8,15,22,29,43, and 64 days. Before sampling, each soil was mixed thoroughly with a laboratory spoon.…”