Thammisetty Venkata Rao and Atmakuru Ramesh
A sensitive multi-residual analytical method based on Gas Chromatography Electron impact Ionization Mass Spectrometry (GC-EI-MS) has been developed for the simultaneous determination of twelve azole group of fungicides (Tetraconazole, Penconazole, Tricyclazole, Paclobutrazole, Hexaconazole, Diniconazole, Propiconazole, Tebuconazole, Epoxyconazole, Etoxazole, Fluquinconazole, Difenconazole) in market fish samples. The composite samples were homogenized, freeze dried and ground to obtain powdered samples which were extracted by the Soxhlet extraction procedure using a hexane-acetonitrile mixture (v/v, 3:1). The extracts were cleaned using florisil and analysed for azoles using GC-MS. The method was validated in fish samples spiked with investigated compounds at different concentration levels (0.005 and 0.05 μg/g). The average recoveries (n=5) ranged between 85-105% with a relative standard deviation (RSD) of less than 5%. This method has the lowest limit of quantification (LOQ) at 0.005 μg/mL and the limit of detection (LOD) at 0.001μg/mL. The developed method was applied successfully for the determination of residues in market fish samples.