Rapid Determination of Pyrethroid Pesticide Residues in Vegetables and Fruits by Gas Chromatography

Objective To establish a rapid method for determination of pyrethroid pesticide residues in vegetables and fruits,and to monitor chemical pollution in foods in Guangdong province.Method The pesticide residues of samples were extracted with petroleum ether,concentrated and cleaned up by Florisil solid phase extraction column,and then determined by gas chromatography with electron detector.The column was DB-1 capillary column(30 m×0.25 mm×0.25 μm).Results When pesticide residues in vegetables and fruits were at the 5.0 μg/kg level,the mean recovery in pakchois ranged from 86.2% to 93.4%,and the relative standard deviation was from 3.4% to 8.6%.The mean recovery of apples ranged from 87.3% to 92.8%,and the relative standard deviation was from 2.8% to 8.1%.5 pyrethroid pesticide residues from 511 vegetable and fruit samples were detected.The detection rate of pyrethroid residues was 17.4% and the over-standard rate was 0.59%.Conclusion Compared with GB/T 5009.146—2003,the method could be rapid,accurate and suitable for fast analysis of pyrethroid pesticide residues in vegetables and fruits.