Challenges of Limiting Pesticide Residues in Fresh Vegetables: The Indian Experience

India is the second largest producer of vegetables after China, and accounts for 13.4% of world production. Surveys carried out by institutions spread throughout the country indicate that 50-70% of vegetables are contaminated with insecticide residues. Rapid, inexpensive and sensitive methods such as pesticide finger printing technique and enzyme-linked immunosorbent assay developed at CFTRI, Mysore, together with GC analysis revealed that in most cases the residue burden was less than the maximum residue limits (MRLs), with some exceptions. Frequently DDT and HCH residues were detected. Evidence suggests that chemical residues in vegetables are due to pick-up from the contaminated soil by plants and migration to edible parts. Bacterial cultures capable of degrading HCH have been isolated at CFTRI and successfully deployed as “Agrocure” to combat HCH residues through accelerated degradation of the chemical in soil. Pseudomonas ptm+ strain developed at CFTRI produced an extracellular surfactant, which was exploited as a cleaning agent “Baxeklen” to dislodge pesticide residues in vegetables. Bioremediation and biocleaning are the redeeming technologies useful to limit pesticide residues in vegetables.