Analysis of eight organophosphorus pesticide residues in fresh vegetables retailed in agricultural product markets of Nanjing, China

A method to effectively remove pigments in fresh vegetables using activated carbon followed cleanup through solid phase extraction (SPE) cartridge to further reduce matrix interference and contamination, was established to determine eight organophosphorous pesticides (OPPs) by gas chromatography (GC) with nitrogen-phosphorus detection (NPD) in this study, and it has been successfully applied for the determination of eight OPPs in various fresh vegetables with the recoveries ranging from 61.8% to 107%. To evaluate eight OPPs residue level, some fresh vegetables retailed at three agricultural product markets (APM) of Nanjing in China were detected, the results showed that phorate in Shanghai green (0.0257 mu g g(-1)) and Chinese cabbage (0.0398 mu g g(-1)), dimethoate in Shanghai green (0.0466-0.0810 mu g g(-1)), Chinese cabbage (0.077 mu g g(-1)), and spinach (0.118-0.124 mu g g(-1)), methyl-parathion in Shanghai green (0.0903 mu g g(-1)), Chinese cabbage (0.157 mu g g(-1)), and spinach (0.0924 mu g g(-1)), malathion in Shanghai green (0.0342-0.0526 mu g g(-1)), chorpyrifos in spinach (0.106-0.204 mu g g(-1)), and Chinese cabbage (0.149 mu g g(-1)), chlorfenvinfos in carrot (0.094-0.131 mu g g(-1)), were found. However, fonofos and fenthion were not detected in all the collected vegetable samples.