Dissipation of endosulfan residues from unprocessed and processed brinjal (Solanum melongena L.) fruits.

In the summer season of 1980, brinjal crop (Solanum melongena L.) raised under field conditions in the Hissar region, India, was studied for endosulfan residues, with particular reference to the influence of washing and boiling/cooking of the fruits on the persistence of endosulfan. Endosulfan was applied three times at intervals of 15 days each. For analysis, fruits were sampled from the first and third spraying at 0, 1, 3, 6, 10, and 15 days. They were analysed colorimetrically for residues. Recovery of endosulfan was 99.61%. In unprocessed fruits, the initial samples contained 2.13 and 2.53 ppm, the final samples 0.12 and 0.25 ppm, which means an endosulfan dissipation of 90.12 and 94.37%. With increasing time the dissipation speed decreased. The half-life values were 4.01 and 5.20 days. Washing and boiling/cooking the fruits decreased the endosulfan content by 42.06 to 64.41 and 67.94 to 78.66%, respectively. The endosulfan residues were below the prescribed tolerance level of 2 ppm within one day of spraying in unprocessed fruits, while in washed and boiled/cooked fruits, even the initial deposits were below the tolerance level.