Determination of residues of deltamethrin in Alphonso mango by HPLC

Residues of deltamethrin, a pyrethroid insecticide has been determined in Alphonso mango by high -performance liquid chromatography with UV detection at 233 nm after extraction by chloroform and a silica gel clean-up. Deltamethrin was sprayed at recommended (9 ml/10 lit) and double recommended (18 ml/10 lit) doses on Mango trees. Mangoes from such treated trees were harvested and analyzed at 1, 5, 10, 15 and 25th day after spraying. Recommended dose showed residue of 0.14 ppm which was reduced to 0.08 ppm on 5th day and thereafter was not detectable. Double recommended dose recorded residue of 0.20 ppm which was reduced to 0.12 ppm on 5th day and later was not detectable.