Dissipation and Decontamination of Residues of Three Pesticides in Okra Fruits

Three pesticides viz cypermethrin, λ-cyhalothrin and endosulfan @ 60, 15 and 300 g ai ha⁻¹, respectively, were applied on okra crop and the residues were determined in fruits at different time intervals. The initial deposits were 0.53 ug g⁻¹ for cypermethrin @ 60 g ai ha⁻¹,0.64 µg g⁻¹ for λ-cyhalothrin @ 15 g ai ha⁻¹ and 9.25 µg g⁻¹ for endosulfan at 300 g ai ha⁻¹. The half-life periods calculated were 3.3, 5.2 and 3.8 days and safe waiting periods were 4.7, 8.6 and 8.3 days for cypermethrin, λ-cyhalothrin and endosulfan, respectively. Residue levels reached below MRL value of each pesticide in 9 days. Washing reduced the residues of cypermethrin, λ-cyhalothrin and endosulfan maximum up to 37.4, 35.6 and 23.8%, respectively.