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1.
J Agric Food Chem ; 72(2): 1017-1024, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38170676

RESUMO

Locally sourced waste cooking oil (WCO) was successfully base-catalyzed and transesterified with methanol into biodiesel to produce biostimulant (nitrobenzene) formulations and replace high-risk carrier solvents. Ideal synthesis conditions were composed of 1% NaOH, MeOH/oil molar ratio (6:1), reaction temperature (65 °C), a 3 h mixing rate, and 97-98% yields. Gas chromatography-mass spectrometry (GC-MS) analysis identified five fatty acid methyl esters (FAMEs) including palmitic, linoleic, oleic, stearic, and eicosenoic acids with high solubilization and olfactory characteristics. Using anionic and nonionic emulsifiers in conjunction with recycled biodiesel, a stable emulsifiable concentrate (NB 35% EC) was created with greater storage stability, wettability, and spreading capabilities than those of organic solvent-based ones. The highest counts of fruits per plant (35.80), flowers per plant (60.00), yield per plant (3.56 kg), and yield per hectare (143.7 quintals) were recorded in treatments with 4 mL/L biodiesel-based EC in field bioassays. In addition to having superior biosafety, FAME-based EC exhibits minimal phytotoxicity and is less harmful to aquatic creatures. It was discovered that the average cost-effectiveness was 5.49 times less expensive than solvent-based EC. In order to utilize waste oils as a locally obtained, sustainable alternative solvent with a wide solubilization range, low ecotax profile, circular economy, and high renewable carbon index, this integrative technique was expanded.


Assuntos
Biocombustíveis , Óleos de Plantas , Óleos de Plantas/química , Solventes , Esterificação , Biocombustíveis/análise , Ácidos Graxos/química , Culinária , Catálise
2.
Environ Monit Assess ; 195(9): 1067, 2023 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-37598129

RESUMO

Monitoring pesticide residue levels becomes crucial to maintain quality and guarantee food safety as the consumption of onion green leaves and immature and mature bulbs (either raw or processed) rises. A field experiment was conducted for two consecutive seasons with quizalofop-p-ethyl (5% EC) at 50 and 100 g a.i. ha-1 to evaluate weed control efficiency and to determine terminal residues. Post-emergence application of fop herbicide at 100 g a.i. ha-1 kept the weed density and dry weight reasonably at a lower level and enhanced the productivity of onion with higher economic returns. A rapid, sensitive, and analytical method was developed using high-performance liquid chromatography (HPLC) with excellent linearity (r2 > 0.99). The limit of quantification for quizalofop-p-ethyl was established at 0.04 mg kg-1 with signal to noise (S/N) ratio ≥ 10. The method was successfully applied and initial quantified residues were in the range of 2.5-4.4 mg kg-1 irrespective of seasons and doses. Finally, the presence of targeted herbicide residues in harvested samples was confirmed by liquid chromatography tandem mass spectrometry (LC-MS/MS) under optimized operating conditions. Dietary risk assessment assured harvested onions were safe for consumption at the recommended dose. It also can be concluded that quizalofop ethyl did not adversely influence soil micro-organisms at standard rates of application.


Assuntos
Herbicidas , Controle de Plantas Daninhas , Cebolas , Cromatografia Líquida , Espectrometria de Massas em Tandem , Monitoramento Ambiental , Inocuidade dos Alimentos
3.
J AOAC Int ; 106(5): 1209-1219, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36622007

RESUMO

BACKGROUND: The presence of undesirable substances, including pesticides (xenobiotics) in betel leaf (Piper betel), is a great concern for consumers because it is chewed and consumed directly. To protect the consumer's health, a modified QuEChERS method for monitoring purposes and subsequent decontamination process has been developed. OBJECTIVE: The goal of this work was to establish a multi-residue analytical method for monitoring nonpermitted organophosphorus pesticide residues in betel leaf, as well as cost-effective cleaning strategies. METHOD: The homogenized 15 g samples (20 betel leaf samples collected in West Bengal, India) were extracted with a modified QuEChERS method using acetonitrile, reconstituted to acetone, and finally analyzed by GC-MS/MS. Possible decontamination techniques (such as tap water washing, 2% saltwater washing, and lukewarm water washing) were evaluated. RESULTS: The limit of detection ranged from 0.003 to 0.005 mg/kg, and limit of quantification was 0.01 mg/kg. Recoveries ranged from 80 to 120% with RSDr 9%. One sample was found to contain three pesticides 4 to 7 times higher than MRLs. Suggested decontamination methods allowed reducing toxic traces below European limits. CONCLUSIONS: The suggested approach is useful for determining pesticide residues in betel leaves quickly. Traditional techniques of processing betel leaves may reduce pesticide residues below regulatory limits. HIGHLIGHTS: A multi-residue method and decontamination of pesticides in betel leaf using QuEChERS-GC-MS/MS technology with satisfactory method performance was achieved. Domestic decontamination techniques have a high efficacy in reducing pesticide residues from betel leaves, making them safe for human consumption.


Assuntos
Resíduos de Praguicidas , Praguicidas , Humanos , Espectrometria de Massas em Tandem/métodos , Resíduos de Praguicidas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Praguicidas/análise , Descontaminação , Compostos Organofosforados/análise , Saúde Pública , Tecnologia , Água/análise , Folhas de Planta/química
4.
Environ Geochem Health ; 45(6): 3683-3698, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36478235

RESUMO

Jute is a healthy vegetable due to its high content of carotenoids, vitamins, and minerals, in addition to its industrial utility. The purpose of this study was to look into the dissipation of fenoxaprop-p-ethyl and to track indirect sources of pesticide accumulation in jute ecosystems for three years in a row during tropical monsoon seasons. To avoid the intake of residues over approved limits, a rapid extraction technique was developed to evaluate the residues of this herbicide (Whip-Super 9% EC) in jute leaves, fiber, cropped soil, and water. A modified QuEChERS approach based on liquid chromatography and ultraviolet-visible (UV-VIS) detection was developed and successfully validated in accordance with SANCO requirements. Gas chromatography mass spectrometer (GC-MS) was used to examine fish and water samples from jute fields and retting pond for twenty widely-used multi-class pesticide contaminations from indirect sources. Relative standard deviations (RSD) (≤ 20) and recoveries (100-115%) are observed to be within acceptable ranges. In edible jute leaves, independent of season, first-order kinetics of dissipation was recorded, with half-lives ranging from 0.61 to 0.68 days. Based on the findings of the risk assessment, it is feasible to conclude that the consumer health risks of ingesting jute leaves are insignificant, even on day zero, when used at the recommended amount, and that using jute bags for food packaging and storage is safe. But jute field water was found to be less polluted with indirect pesticides than water from a nearby jute retted pond. Fish samples from this jute retted pond were also analyzed and found to be 26% contaminated. The presence of quinalphos and chlorpyriphos in jute retting water and fish might pose a concern to consumer health and environmental ecosystems.


Assuntos
Resíduos de Praguicidas , Praguicidas , Animais , Praguicidas/análise , Ecossistema , Poluição Ambiental/análise , Água/análise , Medição de Risco , Resíduos de Praguicidas/análise
6.
Environ Sci Pollut Res Int ; 29(12): 17174-17187, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34661836

RESUMO

A liquid-liquid extraction (LLE) method was validated as per SANTE/12682/2019 guidelines for gas chromatography-mass spectrometric (GC-MS) determination of thirty-six multiclass pesticides in environmental waters. Seasonal (summer, monsoon, and winter) effects on the magnitude of pesticide residues in environmental water (river, pond, and tube well) of six different urban areas of Nadia and North 24 Parganas districts (New alluvial zone, Eastern India) was monitored for subsequent risk assessment. Total 288 water samples (96 each of river, pond, and tube-well) irrespective of locations and seasons were monitored for multiclass multi pesticide residues during the experiment. Each sample (750 mL) was extracted with ethyl acetate/dichloromethane (8:2) liquid-liquid partitioning and filtration (0.22 µm nylon filter paper) and total residue was reconstituted in acetone (1 mL) for GC-MS analysis with developed and validated method resulting satisfactory recovery percentages (77.84-118.15%). The maximum no. of organochlorine (OC) and organophosphorus (OP) pesticide residues were dominated in river and pond water irrespective of seasons and monitoring sites. About 74% of river water samples were found to be contaminated with concerned pesticides in variable magnitudes. Monsoon (July to October) season was highly alarming with the highest presence of total pesticide residues in different types of environmental waters. Risk quotient (RQ) [acute and chronic] was also evaluated in pond and river water as sometimes used for drinking purposes. RQ value (5900) of total endosulfan indicates the highest risk of chronic toxicity to river fishes. Seven water samples from tube-wells were also monitored and found to be contaminated with butachlor and chlorpyriphos in non-significant amounts (< 0.1 ng mL-1), irrespective of seasons and sites, thus safe for consumption.


Assuntos
Água Subterrânea , Resíduos de Praguicidas , Praguicidas , Poluentes Químicos da Água , Monitoramento Ambiental , Resíduos de Praguicidas/análise , Praguicidas/análise , Medição de Risco , Estações do Ano , Poluentes Químicos da Água/análise
7.
Environ Monit Assess ; 193(10): 652, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34528153

RESUMO

The increasing use of gibberellic acid (GA3) to promote fruit growth and yield has necessitated research into its trace level determination and estimation in harvested product. The phytohormone has increased the tomato yield (tonne ha-1) up to 24.7% with uniform fruit shape, size colour and lustre. A fast, simple, high-throughput analytical method was standardised based on electrospray ionisation - liquid chromatography-tandem mass spectrometry (LC-MS/MS). The samples were extracted using acidified (1% formic acid) methanol. The method was validated as per the SANTE/12682/2019 guidelines. The limits of detection (LOD) and quantification (LOQ) were 0.01 and 0.05 mg kg-1. The average recoveries at LOQ and higher levels were in the range of 86-108% with relative standard deviation (RSD) < 20%. The validated method was successfully applied under field condition by following first-order kinetics with half-lives (T1/2) 1.76 days (recommended dose) and 1.99 days (double dose). The estimated pre-harvest intervals (PHIs) were 6 days (recommended dose) and 8 days (double dose). Studies on dietary risk assessment concluded that even after spray of GA3 at recommended dose, the harvested produce (tomato) could be consumed safely.


Assuntos
Solanum lycopersicum , Espectrometria de Massas em Tandem , Cromatografia Líquida , Monitoramento Ambiental , Giberelinas , Medição de Risco
8.
Artigo em Inglês | MEDLINE | ID: mdl-29279005

RESUMO

Multi-location supervised field trials were conducted in India at four locations of the All India Network Project (AINP) on Pesticide Residues to study the persistence, dissipation and risk assessment of flubendiamide and deltamethrin on cucumber (Cucumis sativus). Residues of flubendiamide and deltamethrin on cucumber resulting from three spray applications of a combination formulation (flubendiamide 90% + deltamethrin 60%, 150 SC) at recommended (22.5 + 15 g a.i./ha) and double the recommended (45 + 30 g a.i./ha) dose were analysed. On the basis of persistence and dissipation studies, the half- life (T1/2) of flubendiamide on cucumber varied from 1.40 to 2.98 (recommended dose) and 1.55 to 2.76 days (double the recommended dose), while that of deltamethrin ranged from 2.5 to 4.9 (recommended dose) and 2.7 to 3.9 days (double the recommended dose) at the four locations. On the basis of supervised field trial data and using OECD calculator, MRLs in the combination product of 3 mg kg-1 for flubendiamide and 1.5 mg kg-1 for deltamethrin has been proposed for consideration by the Food Safety and Standards Authority of India (FSSAI). Codex, EU and EPA have fixed MRL of 0.2 mg kg-1 for flubendiamide and deltamethrin.


Assuntos
Benzamidas/análise , Cucumis sativus/química , Contaminação de Alimentos/análise , Nitrilas/análise , Resíduos de Praguicidas/análise , Piretrinas/análise , Sulfonas/análise , Agricultura , Cromatografia Líquida de Alta Pressão , Análise de Alimentos , Humanos , Índia , Espectrometria de Massas , Estrutura Molecular , Medição de Risco
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