Reliable identification of pesticides using linear retention indices as an active tool in gas chromatographic–mass spectrometric analysis

The present research is focused on the current development and employment of a dedicated pesticide mass spectral library, characterized by a double-filter search procedure: the first is based on the degree of spectral similarity and the second on chromatographic retention information (linear retention indices). The highly pure mass spectra contained in the library have been attained by subjecting mixtures of widely used pesticides to comprehensive GC–MS analysis. Linear retention indices for conventional GC–MS analyses were calculated by injecting the same compounds on a single-column GC–MS system. The effectiveness of this approach was verified by analysing a white wine sample spiked with 10 structurally similar pyrethroid compounds, through automated solid-phase microextraction–GC–MS.