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1.
Food Chem ; 452: 139580, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38744129

RESUMEN

The absence of high-affinity antibodies has hindered the development of satisfactory immunoassays for dichlorvos (DDVP) and trichlorfon (TCP), two highly toxic organophosphorus pesticides. Herein, the de novo synthesis of a novel anti-DDVP hapten was introduced. Subsequently, a specific anti-DDVP monoclonal antibody (Mab) was produced with satisfying affinity to DDVP (IC50: 12.4 ng mL-1). This Mab was highly specific to DDVP, and TCP could readily convert into DDVP under mild alkaline conditions. Leveraging this insight, an indirect competitive ELISA was successfully developed for simultaneous detection of DDVP and TCP. The limit of detection in rice, cabbage and apple for DDVP /TCP was found to be 12.1/14.6 µg kg-1, 7.3/8.8 µg kg-1 and 6.9/8.3 µg kg-1, respectively. This study not only provides an effective strategy for producing a high-quality anti-DDVP Mab but also affords a reliable and cost-effective tool suitable for high-throughput detection of DDVP and TCP in food samples.


Asunto(s)
Anticuerpos Monoclonales , Diclorvos , Ensayo de Inmunoadsorción Enzimática , Contaminación de Alimentos , Haptenos , Oryza , Triclorfón , Haptenos/química , Haptenos/inmunología , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/química , Animales , Contaminación de Alimentos/análisis , Ensayo de Inmunoadsorción Enzimática/métodos , Diclorvos/análisis , Oryza/química , Oryza/inmunología , Triclorfón/análisis , Triclorfón/inmunología , Ratones , Ratones Endogámicos BALB C , Malus/química , Brassica/química , Brassica/inmunología , Inmunoensayo/métodos
2.
Sci Total Environ ; 912: 169312, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38104830

RESUMEN

Widespread use of pesticides globally has led to serious concerns about environmental contamination, particularly with regard to aquatic and soil ecosystems. This work involved investigating concentrations of 64 pesticides in surface-water and soil samples collected in four provinces along the Mekong River in Cambodia during the dry and rainy seasons (276 samples in total), and conducting semi-structured interviews with local farmers about pesticide use. Furthermore, an ecological risk assessment of the detected pesticides was performed. In total, 56 pesticides were detected in surface water and 43 in soil, with individual pesticides reaching maximum concentrations of 1300 ng/L in the surface-water samples (tebufenozide) and 1100 ng/g dry weight in the soil samples (bromophos-ethyl). The semi-structured interviews made it quite evident that the instructions that farmers are provided regarding the use of pesticides are rudimentary, and that overuse is common. The perceived effect of pesticides was seen as an end-point, and there was a limited process of optimally matching pesticides to pests and crops. Several pesticides were used regularly on the same crop, and the period between application and harvest varied. Risk analysis showed that bromophos-ethyl, dichlorvos, and iprobenfos presented a very high risk to aquatic organisms in both the dry and rainy seasons, with risk quotient values of 850 for both seasons, and of 67 in the dry season and 78 in the rainy season for bromophos-ethyl, and 49 in the dry season and 16 in the rainy season for dichlorvos. Overall, this work highlights the occurrence of pesticide residues in surface water and soil along the Mekong River in Cambodia, and emphasizes the urgent need for monitoring and improving pesticide practices and regulations in the region.


Asunto(s)
Organotiofosfatos , Residuos de Plaguicidas , Plaguicidas , Contaminantes Químicos del Agua , Ríos/química , Agua/análisis , Suelo , Diclorvos/análisis , Cambodia , Ecosistema , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Plaguicidas/análisis , Residuos de Plaguicidas/análisis
3.
Environ Sci Pollut Res Int ; 30(60): 125664-125676, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38001290

RESUMEN

Trichlorfon, one of the most widely used organophosphate insecticides, is commonly employed in aquaculture and agriculture to combat parasitic infestations. However, its inherent instability leads to rapid decomposition into dichlorvos (DDVP), increasing its toxicity by eightfold. Therefore, the environmental effects of trichlorfon in real-world scenarios involve the combined effects of trichlorfon and its degradation product, DDVP. In this study, we systematically investigated the degradation of trichlorfon in tap water over time using HPLC and LC-MS/MS analysis. Subsequently, an experiment was conducted to assess the acute toxicity of trichlorfon and DDVP on goldfish (Carassius auratus), employing a 1H NMR-based metabolic approach in conjunction with serum biochemistry, histopathological inspection, and correlation network analysis. Exposure to trichlorfon and its degradation product DDVP leads to increased lipid peroxidation, reduced antioxidant activity, and severe hepatotoxicity and nephrotoxicity in goldfish. Based on the observed pathological changes and metabolite alterations, short-term exposure to trichlorfon significantly affected the liver and kidney functions of goldfish, while exerting minimal influence on the brain, potentially due to the presence of the blood-brain barrier. The changes in the metabolic profile indicated that trichlorfon and DDVP influenced several pathways, including oxidative stress, protein synthesis, energy metabolism, and nucleic acid metabolism. This study demonstrated the applicability and potential of 1H NMR-based metabonomics in pesticide environmental risk assessment, providing a feasible method for the comprehensive study of pesticide toxicity in water environments.


Asunto(s)
Insecticidas , Plaguicidas , Animales , Triclorfón/análisis , Diclorvos/toxicidad , Diclorvos/análisis , Carpa Dorada/metabolismo , Cromatografía Liquida , Espectroscopía de Protones por Resonancia Magnética , Espectrometría de Masas en Tándem , Insecticidas/análisis , Plaguicidas/análisis , Agua/metabolismo
4.
Food Chem ; 416: 135822, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-36893638

RESUMEN

Herein, we developed a method coupling TLC and enzyme inhibition principles to rapidly detect OPs (dichlorvos, paraoxon and parathion). After the removal of the organic solvent from the samples using TLC and paper-based chips, the enzyme was added to the detection system. The results showed that the current method effectively reduced the effects of solvents on enzyme behavior. Moreover, the pigments could be successfully retained on TLC with 40% ddH2O/ACN solution (v/v) as a developing solvent. Additionally, the detection limits (LODs) were 0.002 µg/mL for dichlorvos, 0.006 µg/mL for paraoxon, and 0.003 µg/mL for parathion. Finally, the method was applied to spiked cabbage, cucumber, and spinach and showed good average recoveries ranging between 70.22% and 119.79%. These results showed that this paper-based chip had high sensitivity, precleaning, and elimination of organic solvent properties. Furthermore, it provides a valuable idea for sample pretreatment and rapid determination of pesticide residues in food.


Asunto(s)
Paratión , Residuos de Plaguicidas , Plaguicidas , Plaguicidas/análisis , Diclorvos/análisis , Cromatografía en Capa Delgada , Paraoxon/análisis , Residuos de Plaguicidas/análisis , Paratión/análisis , Solventes
5.
Biosens Bioelectron ; 224: 115074, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36638562

RESUMEN

In this study, based on the oxidase activity and photothermal effect of manganese dioxide nanosheets (MnO2 NSs), with thiamine (TH) as the fluorescence response signal and tris (2,2'-bipyridyl) ruthenium (II) hexahydrate as the reference signal, an enzyme-regulated ratiometric fluorescence and photothermal dual-mode probe was constructed for the quantitative detection of organophosphorus pesticide (OPs) residues. OPs reduced the production of the reductive product thiocholine by inhibiting the activity of acetylcholinesterase, thereby regulating the residual amount of MnO2 NSs. With the increase of OPs concentration, the color of the probe solution gradually transitioned from red to blue, and the temperature gradually increased. Using dichlorvos and chlorpyrifos as pesticide models, the developed probes exhibited sensitive responses to OPs in a wide linear range of 0.1-8000 ng/mL. The detection limits of dichlorvos and chlorpyrifos in fluorescence mode were 1.13 × 10-3 ng/mL and 0.86 ng/mL, respectively. The corresponding detection limits in photothermal mode were 1.01 ng/mL and 1.02 ng/mL, respectively. The proposed probe displayed excellent anti-interference and reliability in the analysis of OPs residues in real samples. The dual-mode probe with self-verification function is expected to provide more accurate and robust detection results than the single-mode probe, and has a wider application prospect.


Asunto(s)
Técnicas Biosensibles , Cloropirifos , Plaguicidas , Plaguicidas/análisis , Compuestos Organofosforados/análisis , Diclorvos/análisis , Acetilcolinesterasa/química , Compuestos de Manganeso/química , Reproducibilidad de los Resultados , Óxidos/química , Técnicas Biosensibles/métodos , Colorantes Fluorescentes/química
6.
Artículo en Inglés | MEDLINE | ID: mdl-36586343

RESUMEN

Dichlorvos (DDVP) is an organophosphorous insecticide which is classified as "highly hazardous" Class 1B chemical by World Health Organization (WHO) and largely misused for the purpose of self-poisoning in developing countries. Forensic toxicology laboratories are routinely encountering cases of pesticide poisoning due to their fatal intoxication. Herein; a method is described based on vortex-assisted dispersive liquid-liquid microextraction (VA-DLLME) coupled with Gas Chromatography-Mass Spectrometry (GC-MS) for the determination of an organophosphorous insecticide; dichlorvos (DDVP) in human autopsy samples (blood, stomach content and liver). Under the optimum conditions, the method was found to be linear in the range of 0.5-10 µg mL-1 and 1.5-10 µg g-1 for blood and tissue samples, respectively. Limit of quantification was set at 0.55 µg mL-1 and 1.1 µg g-1 for blood and tissue samples, respectively. Intraday and inter-day precisions were less than 8 and 12 %, respectively. Good recoveries in the range of 86-95 % were obtained for the proposed procedure. The method has been satisfactorily applied for the determination of DDVP in autopsy samples from two different cases received in our laboratory. In comparison to previous methods; the proposed method is relatively short, high sample throughput, inexpensive and adheres to the principles of green analytical chemistry (GAC) for determination of DDVP in human autopsy samples. The method can be adopted in forensic toxicological laboratories for analysis of DDVP in autopsy samples. In addition, the green character of the proposed method was evaluated using ComplexGAPI procedure.


Asunto(s)
Insecticidas , Microextracción en Fase Líquida , Humanos , Cromatografía de Gases y Espectrometría de Masas/métodos , Diclorvos/análisis , Insecticidas/análisis , Hígado/química , Microextracción en Fase Líquida/métodos , Límite de Detección
7.
Artículo en Inglés | MEDLINE | ID: mdl-36111817

RESUMEN

Pollution of water by persistent organic pollutants is well described; however, little is known about the accumulation of these pollutants by aquatic organisms. For this reason, a method based on QuEChERS extraction and gas chromatography coupled to tandem mass spectrometry (GC-MS/MS) was developed for the determination of pesticides, polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in the muscles of five fish species from the bay of Soumbedioune (Dakar, Senegal). This method shows good recoveries of extraction (68.2-98.1% for pesticides, 83.87-98.10% for PAHs and 81.30-98.15% for PCBs), precision (% RSD ≤ 1%), sensitivity (LODs between 0.001 and 0.079 ng g-1), linearity (R2 ≥ 0.99) and repeatability and reproducibility, evaluated for three concentration levels (10 ng g-1, 200 ng g-1 and 500 ng g-1), ≤ 15% for the majority of pollutants under study except for alachlor, atrazine, acetochlor, dicofol, deltamethrin and dichlorvos where a RSD ≥ 20% was determined for the 10 ng g-1 concentration. Organic pollutants have been detected in fish from the Soumbedioune coast demonstrating the necessity of a regular survey of water and fish in order to protect the populations.


Asunto(s)
Atrazina , Contaminantes Ambientales , Plaguicidas , Bifenilos Policlorados , Hidrocarburos Policíclicos Aromáticos , Animales , Bifenilos Policlorados/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Plaguicidas/análisis , Espectrometría de Masas en Tándem/métodos , Reproducibilidad de los Resultados , Dicofol/análisis , Contaminantes Orgánicos Persistentes , Atrazina/análisis , Diclorvos/análisis , Senegal , Cromatografía de Gases y Espectrometría de Masas/métodos , Peces , Contaminantes Ambientales/análisis , Agua/análisis
8.
Analyst ; 147(14): 3258-3265, 2022 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-35698892

RESUMEN

The abuse of pesticides has introduced a large number of residues in soil and drinking water, which can then enter the food chain and the human body. Monitoring pesticide residues and developing simple and fast detection systems for pesticide residues is urgently needed. In this study, we presented one-pot prepared CdS fluorescent quantum dots (QDs) and explored their sensing application for organic pesticides. The CdS QDs can sensitively and selectively detect three different pesticides, dichlorvos (DDVP), paraquat, and glufosinate-ammonium, through different fluorescence responses. Paraquat can effectively quench the fluorescence of the QDs and DDVP can cause remarkable fluorescent enhancement. Glufosinate-ammonium can induce both 150 nm fluorescent blueshifting and 30-fold fluorescent enhancement. The probe exhibited low detection limits for the three pesticides: 1.44 µM for paraquat, 0.23 mM for DDVP, and 49.8 µM for glufosinate-ammonium. Furthermore, based on the results, we utilized the powerful functions of smartphones to establish a concentration-gray value standard curve through RGB values and gray values to realize the qualitative detection and quantitative analysis of DDVP. It is believed that this work presents a new platform for the simultaneous detection of multiple pesticides using a single QDs probe. The present on-site method using a smartphone is of great potential for water monitoring in rural areas.


Asunto(s)
Agua Potable , Residuos de Plaguicidas , Plaguicidas , Puntos Cuánticos , Diclorvos/análisis , Agua Potable/análisis , Colorantes Fluorescentes/química , Humanos , Paraquat/análisis , Residuos de Plaguicidas/análisis , Plaguicidas/análisis , Puntos Cuánticos/química , Espectrometría de Fluorescencia/métodos
9.
Food Chem ; 347: 128986, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-33515969

RESUMEN

Pigeonpea grains are important sources of vegetarian proteins. It is the paramount importance to check the pesticide residues due to their frequent use during production. The LC-MS/MS and GC-MS/MS analytical method was developed and validated for the simultaneous determination of 79 pesticide residues in pigeonpea. The LOD and LOQ of the analytical method were in the range of 0.53 to 3.97 and 1.60 to 10.05 µg kg-1, respectively, with a correlation coefficient of more than 0.997. Average recoveries were in the range of 80 to 118.8%, with the RSD of less than 15%. Measurement uncertainty (Ux) for pesticides was in the range of 3.42 to 12.76 µg kg-1 evaluated at 50 µg kg-1. The method was applied to analyze the sample collected from the farmer's field. This method could be useful for routine analysis of selected pesticide residue for monitoring purposes.


Asunto(s)
Cajanus/química , Cromatografía de Gases y Espectrometría de Masas , Residuos de Plaguicidas/análisis , Espectrometría de Masas en Tándem , Cajanus/metabolismo , Cromatografía Líquida de Alta Presión , Diclorvos/análisis , Grano Comestible/química , Grano Comestible/metabolismo , Límite de Detección , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem/métodos , Trifluralina/análisis
10.
Food Chem ; 331: 127352, 2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-32652343

RESUMEN

The influence of some additives, including metal ions, antioxidants, enzyme inhibitors and organic solvents, on the storage stability of four organophosphorus pesticides in cucumber samples were investigated. It was found that metal ions, including Al3+, Fe3+, and Co2+, increased the stability of dichlorvos, malathion, and chlorpyrifos. Conversely, Al3+, Fe3+, Fe2+, and Co2+ caused catalytic degradation of diazinon. With the addition of organic solvents (CH2Cl2, CHCl3, CCl4, CH3OH and CH3COCH3), remaining of diazinon residues was higher (16-54%) after storage for seven days. CCl4 was associated with the highest retention of malathion, diazinon, and chlorpyrifos (33%, 48% and 44%, respectively) in samples. SDS also stabilized the pesticides since residues were, again, higher (13-38%) after seven days storage. Furthermore, addition of Al3+ and Fe3+ decreased peroxidase (POD) activity and inhibited degradation of dichlorvos and malathion. After 14 days, lyophilization increased the pesticide residues remaining by 36%, 29%, and 58% for diazinon, malathion and chlorpyrifos, respectively. Overall, the stability of these pesticides during storage is impacted by water content and addition of exogenous substances. This could ensure higher quality of pesticide residue data in samples.


Asunto(s)
Cucumis sativus/química , Contaminación de Alimentos/análisis , Almacenamiento de Alimentos , Insecticidas/química , Compuestos Organofosforados/química , Aluminio/química , Cloropirifos/análisis , Cloropirifos/química , Diazinón/análisis , Diazinón/química , Diclorvos/análisis , Diclorvos/química , Aditivos Alimentarios/química , Liofilización , Insecticidas/análisis , Malatión/análisis , Malatión/química , Compuestos Organofosforados/análisis , Oxidorreductasas/química , Peroxidasas/química , Peroxidasas/metabolismo , Residuos de Plaguicidas/análisis , Residuos de Plaguicidas/química , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Dodecil Sulfato de Sodio/química , Agua/química
11.
Mikrochim Acta ; 187(7): 419, 2020 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-32613298

RESUMEN

A novel fluorescence strategy based on the outstanding catalytic capability of CuS nanoparticles (CuSNPs) has been developed for highly sensitive and specific determination of o,o-dimethyl-o-2,2-dichlorovinyl phosphate (DDVP) under enzyme-free and hydrogen peroxide (H2O2)-free conditions. In the presence of DDVP, CuSNPs can catalyze non-fluorescence substratum of Amplex red (AR) into resorufin, which exhibits fluorescence emission at 584 nm under excitation at 540 nm. The sensing system exhibits outstanding specificity and only responds to DDVP and no other organophosphorus pesticides (OPs). A wide linear range is obtained from 0.0001 to 0.1 µg/mL, and the limit of detection (LOD) is 0.1 ng/mL. Furthermore, paper-based test strips have been constructed for visual detection of DDVP under ultraviolet light irradiation. By integrating a smartphone installed with Color Picker APP, point-of-care detection with quantitative determination is realized, demonstrating substantial potential applications of the as-developed assay for in situ detection. Graphical abstract.


Asunto(s)
Colorimetría/métodos , Diclorvos/análisis , Nanopartículas del Metal/química , Plaguicidas/análisis , Teléfono Inteligente , Catálisis , Colorimetría/instrumentación , Cobre/química , Fluorescencia , Colorantes Fluorescentes/química , Contaminación de Alimentos/análisis , Límite de Detección , Solanum lycopersicum/química , Malus/química , Oxazinas/química , Oxidación-Reducción , Papel
12.
Anal Bioanal Chem ; 411(29): 7879-7887, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31691847

RESUMEN

A biomass nitrogen and sulfur codoped carbon dots (NS-Cdots) was prepared by a simple and clean hydrothermal method using leek, and was employed as efficient fluorescent probes for sensitive detection of organophosphorus pesticides (OPs). The leek-derived NS-Cdots emitted blue fluorescence, but was quenched by H2O2. Due to acetylcholinesterase/choline oxidase-based cascade enzymatic reaction that produces H2O2 and the inhibition effect of OPs on acetylcholinesterase activity, a NS-Cdots-based fluorescence "off-on" method to detect OPs-dichlorvos (DDVP) was developed. More sensitivity and wider linear detection range were achieved from 1.0 × 10-9 to 1.0 × 10-3 M (limit of detection = 5.0 × 10-10 M). This developed method was applied to the detection of DDVP in Chinese cabbage successfully. The average recoveries were in the range of 96.0~104.0% with a relative standard deviation of less than 3.3%. In addition, the NS-Cdots fluorescent probes were also employed successfully in multicolor imaging of living cells, manifesting that the NS-Cdots fluorescent probes have great application potential in agricultural and biomedical fields. Graphical Abstract.


Asunto(s)
Inhibidores de la Colinesterasa/análisis , Diclorvos/análisis , Colorantes Fluorescentes/química , Cebollas/química , Puntos Cuánticos/química , Línea Celular Tumoral , Humanos , Límite de Detección , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta
13.
Environ Sci Pollut Res Int ; 26(33): 34622-34632, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31654308

RESUMEN

Organophosphorus pesticides are effective, cheap, and used extensively but can harm aquatic organism and human health. Here, water quality criteria (WQCs) for dichlorvos (DDVP) and malathion (MAL) were derived. Nine aquatic organisms native to China were used in toxicity tests. Published toxicity data for aquatic organisms native and non-native to China were also analyzed. DDVP and MAL WQCs were derived using (log-normal model) species sensitivity distributions. Species sensitivity distribution curves indicated native and non-native species have different sensitivities to DDVP. The sensitivities of native and non-native species to MAL were not different because non-native species data for fewer than eight genera were available, so further research is required. The results indicated that native species need to be considered when deriving WQCs. The criteria maximum concentration (CMC) and criteria continuous concentration (CCC) were 1.33 and 0.132 µg/L, respectively, for DDVP, and 0.100 and 0.008 µg/L, respectively, for MAL. The CMCs for DDVP and MAL derived using ETX 2.0 software and species sensitivity ranks were different from the CMCs obtained using the SSD method because of parameter uncertainties. The DDVP and MAL WQCs were significantly lower than Chinese surface water quality standard thresholds. The results provide basic data for revising these thresholds.


Asunto(s)
Diclorvos/análisis , Malatión/análisis , Plaguicidas/análisis , Contaminantes Químicos del Agua/análisis , Calidad del Agua/normas , Animales , Organismos Acuáticos , China , Humanos , Pruebas de Toxicidad
14.
Mikrochim Acta ; 186(6): 390, 2019 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-31152243

RESUMEN

A novel and highly sensitive enzyme inhibition assay was developed for the rapid detection of the organophosphate pesticide dichlorvos and the carbamate pesticide carbofuran. It achieves signal amplification by the secondary catalysis of platinum nanoparticles. Acetylcholinesterase (AChE) is capable of catalyzing the hydrolysis of acetylthiocholine to form thiocholine. Thiocholine causes the aggregation of citrate-capped platinum nanoparticles which then lose their peroxidase-mimicking properties. After addition of pesticides, the activity of AChE is inhibited, less thiocholine is produced, less aggregation occurs, and the peroxidase-mimetic properties are increasingly retained. In the presence of tetramethylbenzidine and H2O2, a deep blue coloration with an absorption maximum at 650 nm will be formed. The assay was applied to the determination of dichlorvos and carbofuran, and detection limits of 2.3 µg·L-1 and 1.4 µg·L-1 were obtained, respectively. Recovery experiments with spiked tap water and pears gave satisfactory relative standard deviations. Graphical abstract The blue product formed by platinum nanoparticle-catalyzed oxidation of 3,3'5,5'-tetramethylbenzidine (TMB) by H2O2 is reduced if acetylthiocholine (ATCh) is hydrolyzed by acetylcholinesterase (AChE) to form thiocholine. However, if AChE is inhibited by pesticides, color formation will recover.


Asunto(s)
Carbofurano/análisis , Colorimetría/métodos , Diclorvos/análisis , Nanopartículas del Metal/química , Plaguicidas/análisis , Acetilcolinesterasa/química , Acetiltiocolina/química , Bencidinas/química , Materiales Biomiméticos/química , Inhibidores de la Colinesterasa/análisis , Agua Potable/análisis , Peróxido de Hidrógeno/química , Límite de Detección , Peroxidasa/química , Platino (Metal)/química , Tiocolina/química , Contaminantes Químicos del Agua/análisis
15.
Biomed Chromatogr ; 33(7): e4537, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30897223

RESUMEN

A simple pretreatment method with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed and validated to simultaneously determine dichlorvos and phoxim in tobacco and soil matrices. Satisfactory linearity (R2 ≥ 0.9991) of the method was obtained for both analytes. The limits of detection and limits of quantification for dichlorvos and phoxim in three matrices were 0.0015-0.006 and 0.005-0.02 mg/kg, respectively. Average recoveries were 78.24-92.21% for dichlorvos and 76.62-100.51% for phoxim in soil, green tobacco leaves and cured tobacco leaves. The intra- and inter-day relative standard deviations were <6%. The established method was successfully applied for the residual analysis of dichlorvos and phoxim in real soil and tobacco samples. The results indicated that the established method could be used to detect trace amounts of dichlorvos and phoxim in tobacco. The data could also help the Chinese government establish maximum residue limits of dichlorvos and phoxim on tobacco and establish proper and safe use of dichlorvos and phoxim on tobacco plants in China.


Asunto(s)
Cromatografía Liquida/métodos , Diclorvos/análisis , Nicotiana/química , Compuestos Organotiofosforados/análisis , Residuos de Plaguicidas/análisis , Espectrometría de Masas en Tándem/métodos , Límite de Detección , Modelos Lineales , Hojas de la Planta , Reproducibilidad de los Resultados
16.
Water Res ; 138: 272-281, 2018 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-29614455

RESUMEN

As reclaimed water use is increasing, its safety attracts growing attention, particularly with respect to the health risks associated with the wide range of micropollutants found in the reclaimed water. In this study, sophisticated analysis was conducted for water samples from a water reclamation and ecological reuse system where domestic wastewater was treated using an anaerobic-anoxic-oxic unit followed by a membrane bioreactor (A2O-MBR), and the reclaimed water was used for replenishing a landscape lake. A total of 58 organic micropollutants were detected in the system, consisting of 13 polycyclic aromatic hydrocarbons (PAHs), 16 phenols, 3 pesticides, and 26 pharmaceuticals and personal care products (PPCPs). After treatment by the A2O-MBR process, effective removal of pesticides and phenols was achieved, while when the reclaimed water entered the landscape lake, PPCPs were further removed. From the physicochemical properties of micropollutants, it could be inferred that phenols and dichlorphos (the only pesticide with considerable concentration in the influent) would have been mainly removed by biodegradation and/or volatilization in the biological treatment process. Additionally, it is probable that sludge adsorption also contributed to the removal of dichlorphos. For the predominant PPCP removal in the landscape lake, various actions, such as adsorption, biodegradation, photolysis, and ecologically mediated processes (via aquatic plants and animals), would have played significant roles. However, according to their logKoc, logKow and logD (pH = 8) values, it could be concluded that adsorption by suspended solids might be an important action. Although carcinogenic and non-carcinogenic risks associated with all the detected micropollutants were at negligible levels, the hazard quotients (HQs) of PPCPs accounted for 92.03%-97.23% of the HQTotal. With the significant removal of PPCPs through the ecological processes in the landscape lake, the safety of reclaimed water use could be improved. Therefore, the introduction of ecological unit into the water reclamation and reuse system could be an effective measure for health risk reduction posed by micropollutants.


Asunto(s)
Reactores Biológicos , Reciclaje , Eliminación de Residuos Líquidos/métodos , Adsorción , Biodegradación Ambiental , Diclorvos/análisis , Diclorvos/metabolismo , Lagos/análisis , Plaguicidas/análisis , Plaguicidas/metabolismo , Preparaciones Farmacéuticas/análisis , Preparaciones Farmacéuticas/metabolismo , Fenoles/análisis , Fenoles/metabolismo , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/metabolismo , Riesgo , Aguas del Alcantarillado/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/metabolismo
17.
J Forensic Sci ; 63(6): 1928-1931, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29601635

RESUMEN

Organophosphates are widely used as pesticides. However, organophosphates are occasionally orally ingested to commit suicide. In this case, a man in his late 80s committed suicide by ingesting both dichlorvos and phenthoate. Autopsy findings revealed a characteristic volatile odor from his mouth, stomach, lungs, liver, and kidneys. The esophageal mucosa was denatured and had lost elasticity. Serum cholinesterase activity was 9 IU/L. Toxicological analyses performed using high-performance liquid chromatography-tandem mass spectrometry revealed that dichlorvos concentrations in the left and right cardiac blood samples were 11.6 and 4.6 µg/mL, respectively. Phenthoate concentrations in the left and right cardiac blood samples were 5.8 and 0.51 µg/mL, respectively. The total amounts of dichlorvos and phenthoate in the stomach were 7.35 and 4.55 g, respectively. The case history, autopsy findings, and toxicological analyses indicated that the cause of death was acute fatal poisoning after oral ingestion of both dichlorvos and phenthoate.


Asunto(s)
Diclorvos/efectos adversos , Intoxicación por Organofosfatos , Compuestos Organotiofosforados/envenenamiento , Suicidio , Anciano de 80 o más Años , Diclorvos/análisis , Contenido Digestivo/química , Humanos , Masculino , Compuestos Organotiofosforados/análisis
18.
Food Chem ; 252: 40-48, 2018 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-29478562

RESUMEN

A chromatographic method involving a single run was validated for the quantification of clanobutin, dichlorvos, and naftazone in products of animal origin. Pork, beef, chicken, milk, and egg samples were extracted with a solution of 0.1% formic acid in acetonitrile, defatted with n-hexane, centrifuged, and filtered prior to analysis using liquid chromatography-tandem mass spectrometry (LC-/MS/MS). The analytes were separated on a C18 column using a solution of 0.1% formic acid and 10 mM ammonium formate (A) and acetonitrile (B) as the mobile phase. A good linearity over 5-50 ng/g concentration range was obtained with coefficients of determination (R2) ≥ 0.9807. The intra- and interday accuracy (recovery %) calculated from 3 fortification levels (5, 10, and 20 ng/g) were 73.2-108.1% and 71.4-109.8%, and the precisions (expressed relative standard deviations (RSDs)) were 0.9-12.9% and 1.8-10.6%, respectively, for the 3 tested analytes in animal originated foods. The limits of quantification (LOQs) ranged between 0.1 and 1 ng/g, thus enabling the quantification of residual levels below the uniform maximum residue limit (MRL) of 0.01 mg/kg set for compounds having no MRL. The designated methodology was successfully applied to monitor various samples collected from Seoul; the tested analytes were not quantified in any of the market samples. Conclusively, the developed method is simple, sensitive, and accurate, and could be used for the detection of pharmaceuticals in various animal food matrices with variable protein and fat contents.


Asunto(s)
Cromatografía Liquida/métodos , Análisis de los Alimentos/métodos , Leche/química , Óvulo/química , Aves de Corral , Carne Roja/análisis , Espectrometría de Masas en Tándem/métodos , Animales , Bovinos , Diclorvos/análisis , Contaminación de Alimentos/análisis , Naftoquinonas/análisis , Factores de Tiempo , Ácido gamma-Aminobutírico/análogos & derivados , Ácido gamma-Aminobutírico/análisis
19.
Environ Sci Pollut Res Int ; 24(29): 22940-22947, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28815365

RESUMEN

Drosophila is a common strawberry pest. In this work, toxicities of the 77.5% EC dichlorvos to 3rd instar larvae and adults of drosophila were evaluated through indoor bioassays and field bioassays, respectively. To insure the safety, dichlorvos dissipation and terminal residue in strawberry by different application methods under field conditions were determined by high-performance liquid chromatography. The decline curves of dichlorvos residues in strawberry corresponded with first-order kinetics, and dichlorvos dissipated rapidly in strawberry with half-life (t1/2) of 7.58-13.17 h. Terminal residues below the maximum residue limit of strawberry and soil in different distance were achieved after 24 h under different application methods. This article provides guidance to the proper and safe use of dichlorvos in agriculture; it is more reasonable that dichlorvos is applied by embedding on the ground near the strawberry plants covered plastic film with holes.


Asunto(s)
Diclorvos/análisis , Drosophila/efectos de los fármacos , Fragaria/química , Residuos de Plaguicidas/análisis , Contaminantes del Suelo/análisis , Suelo/química , Agricultura , Animales , China , Monitoreo del Ambiente , Semivida
20.
Luminescence ; 32(8): 1541-1546, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28660707

RESUMEN

A fluorescent probe was developed and characterized, it consisted of terbium(III) with 3-ally-salicylohydrazide in ethanol, in which the 1:2 [Tb3+ :S1 ] molar ratio was the best stoichiometric ratio for the probe. The ligand 3-ally-salicylohydrazide (S1 ) was synthesized, then was confirmed by IR, CHN, LC-MS and 1 H NMR. The sensitivity of the probe's fluorescence spectra towards the presence of eight organophosphorus pesticides in ethanolic solution was studied, in which the probe showed marked sensitivity towards dichlorvos pesticide. A tangible enhancement of the probe's fluorescence intensity was observed as a consequence of the gradual addition of dichlorvos pesticide. The calculated limit of detection (LOD) was 1.183 µM and limit of quantitation (LOQ) was 3.94 µM. Further characterization of the nature of forces acting in the interaction of the probe with dichlorvos was performed by calculation of binding constants at different temperatures according to the Benesi - Hildebrand equation, and the thermodynamic parameters ΔH, ΔS and ΔG. In order to assess the analytical applicability of the method, the influence of various potentially interfering anion and cations that naturally occur in water and soil were calculated.


Asunto(s)
Diclorvos/análisis , Colorantes Fluorescentes/química , Hidrazinas/química , Compuestos Organometálicos/química , Salicilatos/química , Terbio/química , Fluorescencia , Colorantes Fluorescentes/síntesis química , Compuestos Organometálicos/síntesis química
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