Pesticides are commonly used to increase the yield of food crops all over the world. Regional regulations and product availability determine the specific pesticides applied to a given crop. The range of compounds a crop is exposed to may be further expanded through unintentional means such as drift during application to nearby fields or misuse of pesticides not registered for use with a given crop. Combined with the fact that most labs performing pesiticide analysis will have the need to analyze many different types of produce, there is the need to analyze a wide variety of analytes with high specificity. Furthermore, the term pesticide really refers to the intended use of the compound rather than a chemical class and, in fact, pesticides span a range of chemical classes. The various classes these compounds fall into generally make them compatible with analysis by GC/MS or LC/MS or in some instances both. And so, many labs that analzye for pesticides are obliged to use both techniques to cover the range of expected and unexpected pesticides in order to achieve their goal of ensuring the safety of produce for human consumption. The atmospheric pressure ionization gas chromatography (APGC) mass spectrometry system described in this work is capable of femtogram levels of detection in both APGC and UPLC modes of operation. This project investigated performance of QuECHERs extracts of strawberry, spinach, tomato and pear analyzed by APGC/MS/MS. Twenty GC amenable pesticides, chosen based on the difficulty they present to systems using an EI source, were analyzed using APGC on a tandem quadrupole mass spectrometer operated in MRM mode and monitoring two transitions per analyte. APGC provided improved specificity for these compounds due to its ability to generate intense molecular ions for these analytes. Reproducibility, sensitivity, and linearity were evaluated and will be discussed.

APGC/MS/MS analysis of pesticides in produce

248th National Meeting (2014)

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