Detection of several classes of pesticides and metabolites in meconium by gas chromatography-mass spectrometry

A solid phase extraction method was developed to isolate multiple classes of parent pesticides from meconium. A methanolic/hydrochloric acid methyl ester derivatization with liquid-liquid extraction technique was also developed for the analysis of metabolites. Identification and quantitation was by electron impact gas chromatography-mass spectrometry. For the parent compounds and metabolites, recoveries in spiked meconium ranged between 72-109%, with coefficients of variation ranging from 1.55-16.92% and limits of detection between 0.01-4.15 mu g g(-1). Meconium samples obtained from infants in the Philippines were assayed using these methods, and propoxur, cypermethrin, pretilachlor, malathion, 4,4'-dichlorodiphenyltri-chloroethylene, bioallethrin, and cyfluthrin were detected.