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Study conducted to develop and validate laboratory method using QuEChERS method. QuEChER method was used for the determination of 28 pesticide residues belongs to organochlorine, synthetic pyrethroids and herbicides in Spinach. Sample was extracted by ethyl acetate. Removal of moisture using from sample extract by anhydrous sodium sulphate and magnesium sulphate. Cleaning of matrix and other interferences was done by Primary Secondary Amine (PSA), C18 and activated charcoal. Agilent 7890B model GC-ECD with 7693 auto sampler and 7890A-Agilent Technologies GC with 5975C inert XL EI/CI MSD triple axis mass detector with DB-5MS fused silica capillary column were used for analysis of samples taken for study. Each pesticide spiking concentration was 0.05 ppm level in three replicate whose recovery lies between Codex permissible limit i.e. 70–120%. Relative standard deviation (RSD) < 15%. Codex norms were followed for repeatability and reproducibility check of the instrument. For Linearity check, taking area of lambda cyhalothrin against five different concentration levels of 0.003, 0.010, 0.100, 0.70, 1.00 mg/kg, calibration curve was plotted with regression co-efficient (r2) 0.993. Total uncertainty or combined uncertainty comprise of three main independent uncertainties arise due to weighing of standards, purity of the standard and repeatability of instruments. Expanded uncertainty is twice of the combined uncertainty which lies in three ranges viz., (a) ≤10% (b) 11–15% and (c) 15–20%. All pesticides taken for study were in the range (a) i.e. ≤10%.

Astudy was conducted forthe qualitative and quantitative estimation of 51 pesticides comprising 16 organochlorines, 23 organophosphates, eight synthetic pyrethroids and four herbicides in commonly consumed green vegetables i.e spinach, coriander, chilli, ladyfinger, bottle gourd and bitter gourd collected from various tehsils of Satna district, Madhya Pradesh. Gas chromatography-Electron Capture Detector (GC-ECD), Flame Photometric Detector (GC-FPD) were used for estimation of pesticides and Gas chromatography-Mass Spectrometry (GC-MS) was used for confirmation. Out of 144 samples, 59 samples were found contaminated with pesticide residue. It was observed that most of the bitter gourd samples were contaminated with chlorpyrifos whereas spinach and okra were contaminated with cypermethrin. Nagod samples were found most contaminated (10 out of 18) whereas Rampur Baghelan were least contaminated (6 out of 18). Contamination of chlorpyrifos was predominant in samples of Nagod, Raghurajnagar and Birsinghpur whereas cypermethrin contamination was so in Majhagawa samples. Profenofos and monocrotophos were detected only in Nagod and Raghurajnagar samples.

Objective: To validate in-house QuEChERS method, which scrutinizes and quantify the residue levels of some most frequently used organophosphorus pesticides and to prove a complete workflow for routine multi-residue pesticide analysis in representative bottle guard matrices and study the persistence of 23 organ phosphorus pesticides. Methods: QuEChERS (quick, easy, cheap, effective, rugged and safe) extraction method was followed. Method validation and residue screening of bottle guard samples were conducted by GC-FPD (Gas Chromatography-Flame Photometric Detector) were used to analyse the presence of pesticides whereas confirmation of pesticides was done by GC-MS (Gas Chromatographic-Mass Spectrometer). Results: For bottle guard matrix, LOD (limit of detection) and LOQ (limit of quantification) values are lowest for phorate (0.005 mg/kg and 0.015 mg/kg) and highest for parathion-methyl (0.1 mg/kg and 0.3 mg/kg) respectively. Calibration curve, was plotted between an area of 23 pesticide standard mixture against seven different concentration levels of 0.01, 0.02, 0.05, 0.10, 0.20, 0.50, 1.00 mg/kg with regression coefficient (R 2 ) are in the range of 0.978-0.994. The mean recovered amount at 0.05 mg/kg spikeing concentration are in the range of lowest 0.0413 mg/kg to highest 0.0467 mg/kg and relative standard deviation are in the range of lowest 2.2 to highest 8.571. Conclusion: For ensuring exposure to contaminants, especially by dietary intake, Robust analytical methods were validated for carrying out both research and monitoring programmes and thus for defining limitations and supporting enforcement of regulations.

The hydrotalcite has been synthesized using Al/Mg molar ratios of 1.0–3.0 by grinding at room temperature for 5 min. It shows maximum acid neutralization capacity (285 ml). When hydrotalcite was prepared hydrothermally (175 °C) and by refluxing (80 °C) method it shows low acid neutralization capacity (i.e. 20 and 200 ml respectively). Hydrotalcite has been characterized by FT-IR, TG and P-XRD. The powder X-ray diffraction analysis values 77.638, 3.777, 2.362, 2.218, 1.876 A support double layer hydroxide structure. It is a rapid and cost effective procedure.