GC-MS in the NCI mode was one order of magnitude higher than that of GC-ECD to
pyrethroid compounds, largely because of reduced inference from matrix background [22]. Methane was mainly used as moderating gas [27, 43], but Feo et al.
also found excellent results (instrumental limit of detection, ILOD, 0.02–1.88 pg
injected) when using ammonia as moderating gas [29]. Tandem MS was used for the
determination of pyrethroids in chemical ionization (CI) [36, 38, 65]. Sichilingo
et al. found ILODs in the range 110–400 pg injected [38] operating with methane as
moderating gas, whereas Feo et al. found ILODs ranging between 0.11 and 450 pg
injected operating with ammonia as moderating agent [65].
3.2 LC Methods
Recently, liquid chromatography (LC) and high-performance liquid chromatography (HPLC) technique have been increasingly employed for the determination of
pyrethroid residues in different matrices [36, 66, 67] with the main advantage of
Fig. 1 GC-NCI-MS chromatograms of 14 pyrethroids selected in the study of Feo et al. [29]
Analytical Methods for Determining Pyrethroid Insecticides in Environmental and. . .
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