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The recently registered insecticide, imidacloprid, was applied to three vegetable crops at 20 and 40 g AI ha À1 . The persistence of the parent insecticide and its translocation, along with the quanti®cation of the metabolites formed on these crops are presented. The parent insecticide dissipated with a half-life of 3±5 days and persisted longest on mustard leaves. The detectable limit of the HPLC method was 0.01 mg g À1 . The metabolites 1-(6-chloropyridin-3-yl-methyl)imidazolidin-2-one and 6-chloronicotinic acid were found to be translocated by day 10 in eggplant, cabbage leaves and mustard leaves but not in cabbage curd. The MRL of imidacloprid is not documented by the FAO/WHO on these crops and comparison of the MPI with the TMRC, calculated on the residue data generated in this study, establishes the safety of the schedule.

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Protocol for the determination of pesticides residues in honey samples have been standardized using a simple technique of liquid–liquid extraction. The method is sensitive to detect low levels of pesticides in honey. Honey sample was fortified with pesticides, namely, cypermethrin, fenvalerate, alphamethrin, lamba–cyhalothrin, endosulfan (α, β and sulfate) and chlorpyrifos. The method of extraction and clean up was optimized and validated in the laboratory. The method was applied to screen six samples of honey locally available for pesticides residues. Recoveries ranged from 60% to 90.6% with RSDs from 2% to 10%. Low recoveries were recorded for α and β -endosulfan in the range of 60%–71%. The LOQs, varied from 0.05 to 1.0 mg kg−1.

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An Electrochemical micro Analytical Device (EµAD) was fabricated for sensitive detection of organophosphate pesticide chlorpyrifos in the food chain. Gold microelectrode (µE) modified with Zinc based Metal Organic Framework (MOF-Basolite Z1200) and Acetylcholinesterase (AChE) enzyme served as an excellent electro-analytical transducer for the detection of chlorpyrifos. Electrochemical techniques such as Cyclic Voltammetry (CV), Electrochemical Impedance Spectroscopy (EIS) and Differential Pulse Voltammetry (DPV) were performed for electrochemical analysis of the developed EµAD. The sensor needs only 2 µL of the analyte and it was tested within the linear range of 10 to 100 ng/L. The developed EµAD’s limit of detection (LoD) and sensitivity is 6 ng/L and 0.598 µ A/ng L−1/mm2 respectively. The applicability of the device for the detection of chlorpyrifos from the real vegetable sample was also tested within the range specified. The fabricated sensor showed good stability with a shelf-life of 20 days. The EµAD’s response time is of 50 s, including an incubation time of 20 s. The developed EµAD was also integrated with commercially available low-cost, handheld potentiostat (k-Stat) using Bluetooth and the results were comparable with a standard electrochemical workstation.

Pesticide contamination of soil and ground water at or near the agricultural fields is a major problem world wide. The ability of several amendments like rice straw, manure, saw dust and charcoal were used to stimulate the degradation of atrazine in soil. Field soil fortified with pesticide at two concentration levels were amended separately with rice straw, farm yard manure, saw dust and charcoal at rates of 2.5% (w/w) and maintained at field capacity moisture regime and kept at ambient temperature 25 +/- 5 degrees C. The results indicate 89.5% degradation of atrazine in farm yard manure during 60-day period followed by rice straw, saw dust charcoal and recording 87.2% and 83.8%, 67.7%, respectively, as compared to unamended treatment where 63.3% degradation was observed. The FYM was found to be most effective in soil and enhances the degradation as compared to the other amendments. Although addition of organic manures has been an integral part of sustainable agriculture practices; the present findings give a new dimension of it's utilization for removal of persistent pesticides.

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