Determination of acephate, methamidophos and monocrotophos in crude palm oil

A method for the determination of acephate, methamidophos and monocrotophos in oil matrices is described. Pesticide residues in crude palm oil were extracted with acetonitrile, and a clean-up process was performed by cooling the entire extract below 10 °C, followed by a discolouring process using a Carbograph SPE cartridge. The extract was analysed using gas chromatography coupled with a pulsed flame photometry detector. The limit of detection for the method was calculated from regression data, and the recovery test results were in the range of 85–109%.