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This study presents the contents of α-methylenecyclopropylglycine, a potentially toxic amino acid, in the peel, pulp and seed fractions of two well-known litchi varieties, namely Shahi and China, over a span of three harvest-seasons. For analysing α-methylenecyclopropylglycine, an LC-MS/MS-based method was validated. The method-accuracies fell within 75–110 % (RSD, <15 %) at 0.1 mg/kg (LOQ) and higher levels. A comparative evaluation of the results in peel, pulp and seed at 30 days before harvest (DBH), 15-DBH, and edible-ripe stage revealed that α-methylenecyclopropylglycine content increased as the litchi seeds grew towards maturity, regardless of the cultivar. In arils, at maturity, the concentration of α-methylenecyclopropylglycine ranged from not-detected to 11.7 μg/g dry weight. The Shahi cultivar showed slightly higher α-methylenecyclopropylglycine content in comparison to China litchi. This paper presents the first known analysis of combined seasonal data on different fruit components at various growth stages for the two chosen litchi cultivars grown in India. • An LC-MS/MS method optimised for estimation of α-methylenecyclopropylglycine in litchi • MCPG was quantified in peel, seed and aril of China and Shahi litchi at 3 growth stages • MCPG in litchi aril ranged between 0 and 11.7 μg/g DW • Shahi litchi showed slightly higher MCPG content over China cultivar • Ripe arils showed higher MCPG over unripe in Shahi cultivar [ABSTRACT FROM AUTHOR]

A liquid chromatography tandem mass spectrometry (LC–MS/MS) based method is reported for simultaneous analysis of fipronil (plus its metabolites) and difenoconazole residues in okra. The sample preparation method involving extraction with ethyl acetate provided 80–107% recoveries for both the pesticides with precision RSD within 4–17% estimated at the limits of quantification (LOQ, fipronil = 1 ng g −1 , difenoconazole = 5 ng g −1 ) and higher fortification levels. In field, both the pesticides dissipated with half-life of 2.5 days. The estimated pre-harvest intervals (PHI) for fipronil and difenoconazole were 15 and 19.5 days, and 4 and 6.5 days at single and double dose of field applications, respectively. Decontamination of incurred residues by washing and different cooking treatments was quite efficient in minimizing the residue load of both the chemicals. Okra samples harvested after the estimated PHIs were found safe for human consumption. [ABSTRACT FROM AUTHOR]

• For the first time, an LC-ESI-MS/MS method is reported for captan, captafol, folpet & iprodione. • The scope of the method also includes degradation products of captan and folpet. • Samples were cryogenically comminuted & extracted with acidified ethyl acetate or acetonitrile. • Limits of quantification were ≤0.01 mg/kg for all these pesticides in fruits and vegetables. • This method provides a viable alternative to conventional GC–MS/MS methods with improved precision & accuracy. An improved liquid chromatography tandem mass spectrometry method is reported for the determination of residues of captan (+tetrahydrophthalimide), captafol, folpet (+phthalimide), and iprodione in fruits and vegetables. The optimized electrospray ionization parameters (high cone gas flow, and a low desolvation temperature) did not result in degradation of target compounds, rather they provided a significant advantage over the conventional GC–MS/MS methods, which lack sensitivity and repeatability. Strategies for minimizing losses in recovery of these compounds during sample preparation included cryogenic comminution, extraction with acidified ethyl acetate or acetonitrile, and dilution of the final extract with acidified water prior to LC-MS/MS analysis. The method performance complied with the SANTE/11813/2017 guidelines, with recoveries in the range of 70–120% at the LOQ of 0.01 mg/kg across the tested matrices at various pHs. The efficiency of the method was reflected in its precision (RSDs < 10%) for incurred residues. [ABSTRACT FROM AUTHOR]

Higher matrix interference makes the multi-residue pesticide analysis in spices more challenging. A simple, sensitive, and robust large-scale multi-residue method was developed for the rapid analysis of 243 pesticides in cardamom matrix by gas chromatography tandem mass spectrometry (GC-MS/MS). Prehydration of cardamom in 1:4 sample:water for 30 min improved the homogeneity and extractability. QuEChERS extraction followed by cleanup with 25 mg primary secondary amine, 100 mg C 18 , and 10 mg graphitized carbon black to 1 ml supernatant was used for sample preparation. Reconstitution of final extract in ethyl acetate reduced matrix co-extract up to 60%. The method was validated according to the SANTE/11,945/2015 guidelines. The limit of quantification was ≤0.01 mg kg −1 , and the recovery was within 70.0–120.0%, with ≤20% RSD for the majority of pesticides. The method was used for screening market samples, and the detected residues were devoid of any risk of acute toxicity related to dietary exposure. [ABSTRACT FROM AUTHOR]

A method was validated for the simultaneous analysis of the residues of dimethomorph, famoxadone and cymoxanil in grape and raisin matrix by ethyl acetate based extraction and liquid chromatography tandem mass spectrometric analysis. Field studies were conducted to evaluate the dissipation rate kinetics and processing factor (PF) for these pesticides during raisin making. Residue data during the drying process were best fitted to 1st + 1st order rate kinetics with half-life ranging between 8–9 days for dimethomorph, 12–13 days for famoxadone and 9–10 days for cymoxanil at single dose (SD) and double dose (DD), respectively. PF values calculated were 1.03 and 1.14 for dimethomorph, 1.95 and 2.09 for famoxadone, and 1.99 and 1.35 for cymoxanil at SD and DD, respectively. PF value >1 indicates concentration of the residues during raisin making. The residues of detected pesticides in market samples of raisins were devoid of any risk of acute toxicity related to dietary exposure. [ABSTRACT FROM AUTHOR]

Highlights: [•] Dissipation kinetics of the residues of CPPU, 6-BA, GA3 and Ethephon in grape are reported. [•] Dissipation of residues followed 1st +1st order kinetics. [•] Initial residue of GA3 was below MRL and hence no pre-harvest interval (PHI) is applicable. [•] CPPU, 6-BA and Ethephon residues dissipated with PHIs of 33.5, 12 and 32days, respectively. [Copyright &y& Elsevier]

Abstract: Food safety aspects of buprofezin, dimethoate and imidacloprid residues in pomegranate are reported. The residue analysis involved extraction of samples (15g) with 10ml ethyl acetate, cleanup by dispersive solid phase extraction with 25mg primary secondary amine and 25mg C18 sorbents and estimation by LC–MS/MS. The limit of quantification of each analyte was 0.001mgkg−1 with recoveries within 76–109%. The residues of buprofezin and dimethoate were confined to outer rind, which degraded to below the maximum residue limit for the European Union (EU-MRL) after 10.5 and 31.5days at standard dose and 32.0 and 44.0days at double dose. Residues of imidacloprid penetrated into the albedo and membrane, although at less than the MRL in all samples even at double dose. The dietary exposure of buprofezin and imidacloprid was safe on all sampling days; whereas samples with dimethoate appeared safe after 15 and 30days of field applications at standard and double doses, respectively. [Copyright &y& Elsevier]

Abstract: A novel method for the residue analysis of wine spoilage compound 2,4,6-trichloroanisole is reported. Wine (60ml) was extracted with 2ml toluene in presence of 24g MgSO4 and 6g NaCl. Cleanup of the toluene phase by dispersive solid phase extraction with mixture of 100mg CaCl2, 25mg primary secondary amine and 50mg MgSO4 was effective in minimising co-extractives and matrix effects. Time-of-flight and tandem mass spectrometric parameters were optimised to achieve linearity over 0.25–500ngml−1 and method detection limit 0.0083ngml−1 which is well below the odour threshold of 0.04ngml−1. Recoveries at 0.04, 0.2 and 0.8ngml−1 were within 80–110% (±8%). The method was reproducible when tested for Argentinean wines with intra-laboratory Horwitz ratios being <0.20 in white and red wines at both the laboratories of India and Argentina. The method could be successfully applied for incurred wine samples. [ABSTRACT FROM AUTHOR]