Persistence of Malathion Residues on/in Bell Pepper (Capsicum annuum Linn.)

Persistence of malathion on/in bell pepper fruits was studied in field experiments conducted at the Punjab Agricultural University, Ludhiana, during 1998–99. Spray of malathion @ 500 and 1000 g a.i. ha⁻¹ resulted in initial deposits ranging from 4.65 to 4.83 mg kg⁻¹ and 10.00 to 10.09 mg kg⁻¹, respectively. About 91 to 97% initial concentrations were found to be dissipated in 6 d after its application. Washing of treated fruits with running tap water resulted in removal of 67 to 78% of residues from 0 and 1 d samples. The half-life values (RL₅₀) of malathion on bell pepper varied from 1.18 to 1.29 d and 1.22 to 1.36 d for the respective lower and higher dosages. A waiting period of 5 d has been suggested for the safe consumption of bell pepper following application of malathion at the recommended dosage.