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The persistence of chlorpyrifos, fluopyram, and tebuconazole was estimated in green pods, matured seeds, and soil of French beans using dispersive QuEChERS. Three foliar applications each of chlorpyrifos and a combination fungicide fluopyram + tebuconazole (Luna experience, 400 SC) were applied at 600 and 125 + 125 as a standard dose and 1200 and 250 + 250 g a.i. ha -1 as a double dose, respectively, were applied at an interval of 10 days and treated pods were picked up at regular intervals. Dried mature seeds and soil were also monitored at harvest. The initial deposits of chlorpyrifos on bean pods were 3.083 and 6.017 mg kg -1 with a half-life of 1.86 and 2.29 days, at respective doses. Foliar application of a combi product Luna experience yielded 3.396 and 5.772 mg kg -1 residues of fluopyram and 3.613 and 5.887 mg kg -1 of tebuconazole in green pods at standard and double dose with almost same half-lives of 3.4 and 3.8-3.9 days. Residues declined below the limit of quantitation (LOQ) of 0.05 mg kg -1 in green beans after 15 and 25 days after the application of double dose of chlorpyrifos and Luna experience, respectively. However, the residues in dry bean seeds and soil reached below the LOQ of 0.05 mg kg -1 at the time of harvest. A pre-harvest interval of 5, 10, and 7 days has been proposed for chlorpyrifos, fluopyram, and tebuconazole, respectively, in beans. HQ < 1 and TMDI < MPI in all test chemicals. Hence, it was concluded that a waiting period of 5 days for chlorpyrifos and 7-10 days in Luna experience will be safer to consumers. This data generated will be useful for regulatory agency for fixing MRLs.

A total of 162 samples of different varieties of mango: Deshehari, Langra, Safeda in three growing stages (Pre-mature, Unripe and Ripe) were collected from Lucknow, India, and analyzed for the presence of seventeen organophosphate pesticide residues. The QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method of extraction coupled with gas chromatography was validated for pesticides and qualitatively confirmed by gas chromatography-mass spectrometry. The method was validated with different concentrations of mixture of seventeen organophosphate pesticides (0.05, 0.10, 0.50 mg kg(-1)) in mango. The average recovery varied from 70.20% to 95.25% with less than 10% relative standard deviation. The limit of quantification of different pesticides ranged from 0.007 to 0.033 mg kg(-1). Out of seventeen organophosphate pesticides only malathion and chlorpyriphos were detected. Approximately 20% of the mango samples have shown the presence of these two pesticides. The malathion residues ranged from ND-1.407 mg kg(-1) and chlorpyriphos ND-0.313 mg kg(-1) which is well below the maximum residues limit (PFA-1954). In three varieties of mango at different stages from unpeeled to peeled sample reduction of malathion and chlorpyriphos ranged from 35.48%-100% and 46.66%-100% respectively. The estimated daily intake of malathion ranged from 0.032 to 0.121 µg kg(-1) and chlorpyriphos ranged from zero to 0.022 µg kg(-1) body weight from three different stages of mango. The hazard indices ranged from 0.0015 to 0.0060 for malathion and zero to 0.0022 for chlorpyriphos. It is therefore indicated that seasonal consumption of these three varieties of mango may not pose any health hazards for the population of Lucknow, city, India because the hazard indices for malathion and chlorpyriphos residues were below to one.

Punjab state in India is an agrarian society, where agriculture is the lifeline of farming community. To keep pace with increasing demands of food for growing population the indiscriminate use of pesticides has led to the contamination of environment and food commodities in this region. Analysis of human breast milk samples (n=53) for pesticide residues revealed the presence of β-, γ-HCH, p,p' DDD, p,p' DDE, p,p' DDT and endrin with mean concentration of 97.9, 101.7, 239.8, 1574.1, 100.3 and 90.7 ng g(-1) lipid wt., respectively. In addition, occurrence of β-endosulfan, endosulfan sulphate, cypermethrin and chlorpyrifos in this study have also been reported for the first time in human breast milk in Punjab, India. With increase in parity, HCH and DDT residue burden in donor's milk decreased. Although levels of HCH and DDT residues in breast milk samples have decreased significantly, yet estimated daily intake values for DDT are higher than the FAO/WHO permissible tolerable daily intake values for few infants., (© 2013.)

Residue levels of chlorpyriphos were determined in unprocessed and processed okra fruits to evaluate the effect of different processes (washing and washing followed by boiling/cooking) on reduction of residues of this pesticide in okra. The study was carried out on okra crop (Variety, Varsha Uphar) in research farm of Chaudhary Charan Singh, Haryana Agricultural University, Hisar with application of chlorpyriphos (Radar 20 EC) at 200 g a.i./ha and 400g a.i./ha (Single Dose, T(1)) and 400 g a.i./ha (Double Dose, T(2)). Samples of okra fruits were collected on 0, 1, 3, 5, 7, 10, 15 days and at harvest after treatment. Residues were estimated by GC-ECD system and reached BDL of 0.010 mg kg(-1) on 7th and 15th day in case of single and double dose, respectively. The residues dissipated with half-life period of 3.15 days at lower dose and 3.46 days at higher dose following biphasic first order kinetics. Processing was found very effective in reducing the levels of chlorpyriphos residues in okra fruits. Maximum reduction (64-77%) was observed by washing + boiling followed by washing (13-35%).

A multilaboratory proficiency testing program was conducted by the National Accreditation Board for Testing and Calibration Laboratories (India) and coordinated by the Institute of Pesticide Formulation Technology. This program was conducted to compare the performance of individual laboratories in the area of pesticide formulation (Chlorpyrifos 20 EC) analysis. A total of 24 laboratories in India participated. Analysis of 2 parameters (i.e., estimation of the active ingredient and the acidity) of 2 samples of Chlorpyrifos 20 EC was the objective of this program. Homogeneity tests were performed before sample distribution. Performance of the participating laboratories was evaluated by using new robust statistics given in the guidelines of the National Association of Testing Authorities, Australia. Results were collated and statistically computed to calculate the value of 2 types of Z-scores (Zwi and Zbi). In addition to the statistical analysis, a graphical representation such as the Youden plot was also generated to evaluate the performance of participating laboratories.

The dissipation of chlorpyrifos (20 EC) at environment-friendly doses in the sandy loam and loamy sand soils of two semi-arid fields and the presence of pesticide residues in the harvested groundnut seeds, were monitored. The movement of chlorpyrifos through soil and its binding in the loamy sand soil was studied using 14C chlorpyrifos. Chlorpyrifos was moderately stable in both loamy sand and sandy loam soils, with half-life of 12.3 and 16.4 days, respectively. With 20 EC treatments the dissipation was slower for standing crop than seed treatment, indicative of the high degradation rates in the bioactive rhizosphere. In soil, 3,5,6-trichloro-2-pyridinol (TCP) was the principal breakdown product. Presence of 3,5,6-trichloro-2-methoxypyridine (TMP), the secondary metabolite, detected in the rhizospheric samples during this study, has not been reported earlier in field soils. The rapid dissipation of the insecticide from the soil post-application might have resulted from low sorption due to the alkalinity of the soil and its low organic matter content, fast topsoil dissipation possibly by volatilization and photochemical degradation, aided by the low water solubility, limited vertical mobility due to confinement of residues to the upper 15 cm soil layers and microbial mineralization and nucleophilic hydrolysis. Contrary to the reports of relatively greater mobility of its metabolites in temperate soils, TMP and TCP remained confined to the top 15 cm soil. The formation of bound residues (half-life 13.4 days) in the loamy sand soil was little and not "irreversible." A decline in bound residues could be correlated to decreasing TCP concentration. Higher pod yields were obtained from pesticide treated soils in comparison to controls. Post-harvest no pesticide residues were detected in the soils and groundnut seeds.