ABSTRACT
Pesticide testing in foodstuffs is of great interest for the protection of human health. The international trade of fruits and vegetables, combined with the lack of harmonized pesticide usage regulations worldwide, fosters the development of comprehensive screening methods for analyzing hundreds of pesticides in a unique assay. The use of quadrupole tandem mass spectrometry (GC-MS) libraries for unknown organic compound screening and identification has over 30 years of usage. Liquid chromatography tandem mass spectrometry (LC-MS) mass spectral libraries are necessary for unknown screening methodologies in food, forensics, or environmental analysis. Either unknown screening or nontarget analysis approaches become easier and user-friendlier by means of spectral libraries. Even though accurate mass measurements are universal and not instrument dependent, mass accuracy still represents an important parameter to consider in screening methods based on accurate mass measurements. An additional feature usually included in specific software for accurate mass screening is the examination of isotope profiles for the assigned elemental compositions.
