Quantification of multi-class pesticides in stomach contents and milk by gas chromatography–mass spectrometry with liquid extraction method

Abstract

• Stomach content is the best specimen in acute pesticide poisoning. • Direct detection of pesticides in milk. • Salt-assisted liquid extraction method. • Quantification method of nine multi-class pesticides by GCMS. Pesticides belonging to carbamates, pyrethroids and organophosphate groups are being mostly used worldwide. These are toxic and their minute amount leads to severe illness or death when ingested through various means. In case of suicidal or homicidal incidents, trace levels of pesticides may lead to acute death. In this scenario, stomach content is the best specimen for the detection of pesticide poison. Conversely, trace levels of pesticides may reach the mammary glands of milking animals when they eat grassy feed exposed to pesticides spray. Trace levels of those pesticide residues present in milk remain stable even after pasteurization. Eventually, milk consumers are affected chronically by these pesticide residues. The current study includes the development and validation of nine multi-class pesticide residues analyses in stomach content and milk. Nine-multiclass pesticides were extracted from stomach content and milk by acetonitrile with the addition of extraction salt. Quantitative analysis of permethrin, lambda-cyhalothrin, pyriproxyfen, triazophos, profenophos, chlorpyriphos, carbofuran, phorate, and step, GC–MS was used as an analytical technique equipped with DB-5 ms capillary open tubular column (15 m × 0.25 mm × 0.25 µm) and 0.08 ml/L flow rate of helium mobile phase gas with constant pressure. LLOQ and ULOQ for all target analytes were 0.05 mg/L and 3 mg/L respectively.