Multiresidue analysis of 184 pesticides in high-fat fish feed using a new generic extraction method coupled with gas and liquid chromatography-tandem mass spectrometry

Philipp Rudolf Michael Peter Eyring,Mette Erecius Poulsen,Susan Strange Herrmann

doi:10.1186/s13765-021-00610-9

Abstract

Animal feed is typically plant-based and can contain pesticide residues. Methods for testing food and feed samples, such as the Quick Easy Cheap Effective Rugged Safe (QuEChERS) method or the Swedish Ethyl Acetate (SweEt) method, successfully extract many pesticide residues. However, nonpolar pesticides, such as organochlorine pesticides, show poor recovery when extracted from lipid-rich samples. The previously developed water-acetonitrile-heptane-solid-phase-extraction (WAHSPE) method shows better recoveries for the nonpolar pesticides but requires two injections per sample and per instrument. Here, we present a modified version of the WAHSPE method for pesticides in fish feed using one injection per sample and per instrument. Of the 184 pesticides tested, 179 met the European Union Legislation’s validation criteria at a spike level of 50 μg/kg, showing recoveries between 70 and 120% and a relative standard deviation (RSD) below 20%. Organochlorine pesticides accounted for 14 of the tested compounds.

Highlights

Animal feed is typically plant-based and can contain pesticide residues
QuEChERS and Swedish Ethyl Acetate (SweEt) are widely used methods and generally perform well, some analytes, such as organochlorine pesticides and other nonpolar pesticides, have low recoveries when extracted from lipid-rich samples [6]
Method development The method that was developed was based on the method reported in Eyring et al, but improvements were made by decreasing preparation and instrument time [4]

Summary

Introduction

Methods for testing food and feed samples, such as the Quick Easy Cheap Effective Rugged Safe (QuEChERS) method or the Swedish Ethyl Acetate (SweEt) method, successfully extract many pesticide residues. Nonpolar pesticides, such as organochlorine pesticides, show poor recovery when extracted from lipid-rich samples. The previously developed water-acetonitrile-heptane-solid-phase-extraction (WAHSPE) method shows better recoveries for the nonpolar pesticides but requires two injections per sample and per instrument. QuEChERS and SweEt are widely used methods and generally perform well, some analytes, such as organochlorine pesticides and other nonpolar pesticides, have low recoveries when extracted from lipid-rich samples [6]. A modified version of the WAHSPE method was developed to reduce instrument time by requiring only one injection for each of the analytical techniques (GC-MS/MS or LC-MS/MS)

Objectives

Methods

Results