Dissipation of Endosulfan and Lindane on Sunflower Seeds and Cowpea Pods

Persistence of endosulfan and lindane in emulsifiable concentrate formulations was investigated on sunflower and cowpea at the recommended (T1) and double the recommended (T2), doses. The total residues of endosulfan (Endosulfan A + Endosulfan B) 2.370 μg g−1 in T1 and 3.030 μg g−1 in T2, exceeded MRL value of 2 ppm in sunflower seeds at harvest. The corresponding lindane residues of 0.197 ug g”1 in T, and 0.680 jig g”1 in T2 were also above the MRL value. On cowpea pods, residues of endosulfan in T1 and T2 and lindane in T1 were below their respective MRL values at one DAT. Endosulfan dissipated by about 46–92% and lindane by 26–89% by harvest. Washing and cooking of cowpea pods reduced endosulfan residue by 37–90% and 78–96% respectively. The loss of lindane residues on cooking was 87–90%. A waiting period of 3 d has been suggested for these insecticides on cowpea.