Liquid-solid sample preparation followed by headspace solid-phase microextraction determination of multiclass pesticides in soil

J AOAC Int. 2012 Sep-Oct;95(5):1331-7. doi: 10.5740/jaoacint.sge_durovic.

Abstract

This paper describes development and validation of a multiresidue method for the determination of five pesticides (terbufos, prochloraz, chloridazon, pendimethalin, and fluorochloridone) belonging to different pesticide groups in soil samples by GC/MS, followed by its application in the analysis of some agricultural soil samples. The method is based on a headspace solid-phase microextraction method. Microextraction conditions, namely temperature, extraction time, and NaCI content, were tested and optimized using a 100 microm polydimethylsiloxane fiber. Three extraction solvents [methanol, methanol-acetone (1 + 1, v/v), and methanol-acetone-hexane (2 + 2 + 1, v/v/v)] and the optimum number of extraction steps within the sample preparation stage were optimized for the extraction procedure. LOD values for all the studied compounds were less than 12 microg/kg. Recovery values for multiple analyses of soil samples fortified at 30 microg/kg of each pesticide were higher than 64%. The method was proven to be repeatable, with RSD lower than 15%.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chemistry Techniques, Analytical
  • Pesticides / chemistry*
  • Reproducibility of Results
  • Soil / chemistry*
  • Soil Pollutants / chemistry*
  • Solid Phase Microextraction / methods*

Substances

  • Pesticides
  • Soil
  • Soil Pollutants