Determination of Synthetic Pyrethroids and Hexaconazole Residues in curry leaves and decontamination through
1Pesticide Toxicology Laboratory, Department of Agricultural Entomology, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu 641003 India.
Abstract:
A multiresidue method was developed and validated for the simultaneous determination of eight synthetic pyrethroids and hexaconazole fungicide residues in curry leaves. The method involves extraction of leaf sample with ethyl acetate, purified by dispersive SPE with primary secondary amine and graphitized carbon black. The gas chromatography-electron capture detector (GC-ECD) used for residue estimation and confirmed using gas chromatography-mass spectrometry (GC-MS) with the LOQ of 0.03 μg/g. The recoveries of all pesticides were in the range of 75 to 110% with a relative standard deviation of less than 7%. The matrix effect was within the acceptable limit of less than 20% as prescribed by SANTE guidelines. The decontamination was carried out to reduce the concentration of residues in curry leaves by different household techniques and lemon juice (2%) solution was found to be more effective (35.71-56.52%) followed by 2% tamarind (23.48 to 42.94%), hot water (18.44 to 46.74%), 2% salt water (10.98 to 42.71%) and least in tap water (3.57 to 27.84%). The method was successfully applied for routine monitoring of pesticide residues in curry leaves.
