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1.
Anal Bioanal Chem ; 411(27): 7187-7196, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31620825

RESUMO

Surface-enhanced Raman spectroscopy (SERS) has the potential to detect pesticide residues in agricultural products. However, some systemic pesticides, such as chlorpyrifos, can enter the plant tissue, and not just stay on the surface. Consequently, many SERS studies halted at practical application because of its complexity. In this work, SERS technology was used to detect chlorpyrifos residues in tea products at the semiquantitative level. A simple pretreatment method effectively avoided interference of other fluorescent substances, and all major peaks could be distinguished on the basis of a novel substrate. A principal component analysis algorithm was applied to form a regression model, and a nanogram detection limit was obtained. Furthermore, chlorpyrifos residues in the same tea products were also measured by gas chromatography-mass spectrometry, and the results show a small range of errors. From the comparative study of the two detection methods, the results suggest the great promise of SERS technology for rapid inspection of agricultural products.


Assuntos
Clorpirifos/análise , Resíduos de Praguicidas/análise , Análise Espectral Raman/métodos , Chá/química , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Praguicidas/análise
2.
Environ Monit Assess ; 191(11): 644, 2019 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-31606848

RESUMO

The bayberry is an important economic fruit as well as a minor crop in China, and few pesticide products are registered for bayberry. Prochloraz is a widely used fungicide with a high detection rate on bayberry. This study evaluated the potential dietary risk of prochloraz for different populations in China based on field trial data and market surveillance. The results indicate that one-time applications at dosages of 1000 and 1500 mg/kg with a recommended preharvest interval of 20 days do not pose a chronic or acute dietary risk. However, applying the above dosages twice will cause a potential short-term dietary risk. Risk assessment results conducted on surveillance samples indicated acceptable long-term risks for the general population, with a hazard quotient < 0.82. Furthermore, simulated washing and wine production processes were performed to mimic household practices to investigate residue transfer and distribution. We found that rinsing with tap water for 1 min was an effective way to remove residue, and the processing factors of prochloraz for both bayberry and wine were < 1, indicating that wine production could reduce residue levels. Prochloraz had a strong capacity to transfer to wine due to its high log Kow value, with transfer percentages up to 43%. This study supports the recommendation on good agricultural practices for prochloraz application and provides a guide for safe consumption.


Assuntos
Exposição Dietética/análise , Frutas/química , Fungicidas Industriais/análise , Imidazóis/análise , Myrica/química , Resíduos de Praguicidas/análise , Vinho/análise , China , Dieta , Medição de Risco
3.
J Agric Food Chem ; 67(45): 12576-12583, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31618026

RESUMO

Copper ion (Cu2+)-triggered carbon dots (CDs/Cu) with dual emissions were utilized to develop a ratiometric fluorescence sensor for ultrasensitive detection of inert thiophanate-methyl (TM). TM could be recognized by CDs/Cu through π-π stacking and could chelate Cu2+ of CDs/Cu through metal ion coordination, inducing synchronous fluoresent quenching of the dual emission of CDs/Cu based on the excited state intramolecular proton transfer and the ligand-to-metal charge transfer. The fluorescence ratio of CDs/Cu (F416/F481) linearly responded in a TM concentration of 0.10-20.00 µmol/L with an ultralow limit of detection of 2.90 × 10-6 µmol/L. A synchronous response of the ratiometric sensor enhanced the specificity toward TM and presented remarkable capability of anti-interference in complex matrices. The sensor exhibited satifactory accuracy and precision for practical applications with recoveries of 88.33-101.09% and relative standard deviations of 1.61-5.06%, demonstrating an ultrasensitive ratiometric fluorescent nanosensor for detecting pesticides residues in complex matrices.


Assuntos
Carbono/química , Cobre/química , Medições Luminescentes/métodos , Resíduos de Praguicidas/análise , Pontos Quânticos/química , Tiofanato/análise , Fluorescência , Sensibilidade e Especificidade
4.
Se Pu ; 37(10): 1042-1047, 2019 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-31642281

RESUMO

A method based on QuEChERS-gas chromatography-tandem mass spectrometry (GC-MS/MS) was established for the determination of 20 pesticide residues in wolfberry. The samples were extracted with acetonitrile. The extract was purified with PSA (primary secondary amine), GCB (graphite carbon black) and C18 to suppress the matrix in wolfberry. The analytical results showed that the calibration curves for the 20 pesticides obtained by GC-MS/MS were linear in the range of 5-500 µg/L, with the correlation coefficients higher than 0.99. The recoveries ranged from 70.02% to 110.78% with relative standard deviations (RSDs) ranging from 2.05% to 9.53%. This method has the advantages of being time-saving, convenient and sensitive. The proposed method can simultaneously detect organic phosphorus and organic chlorine pesticides residues with a good performance in terms of qualitative and quantitative detection.


Assuntos
Lycium/química , Resíduos de Praguicidas/análise , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas em Tandem
5.
Se Pu ; 37(9): 955-962, 2019 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-31642299

RESUMO

An improved method to screen 52 pesticide residues in flavored tea using QuEChERS coupled with liquid chromatography-quadrupole-time-of-flight mass spectrometry (LC-Q-TOF-MS) has been investigated. The flavored tea was extracted with acetonitrile and purified using by primary secondary amine (PSA), graphitized carbon black (GCB) and C18 sorbent. The resultant residues were then analyzed using LC-Q-TOF-MS. The recoveries of all the pesticides in flavored tea at the four spiked levels of 10, 20, 50 and 100 µg/kg were 70%-120% and the relative standard deviations (RSDs, n=3) were less than 20%. The calibration curves of the 52 pesticide residues had good linear relationships, and the correlation coefficients were more than 0. 99. The screening detection limits (SDLs) and the limits of quantitation (LOQs) for the 52 pesticides were in the range of 0.001-0.01 mg/kg and 0.002-0.02 mg/kg, respectively, which were lower than maximum residue limits standard permitted by the European Union (EU). This method is simple, rapid, reliable, and can meet the requirements for the simultaneous determination of 52 pesticide residues in flavored tea.


Assuntos
Contaminação de Alimentos/análise , Resíduos de Praguicidas/análise , Chá/química , Cromatografia Líquida , Aromatizantes , Espectrometria de Massas
6.
Se Pu ; 37(9): 1019-1025, 2019 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-31642308

RESUMO

An analytical method for the determination of 34 pesticide residues in plant-derived foods was established using an automated QuEChERS sample preparation system combined with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The sample extraction and dispersive solid-phase extraction in the manual QuEChERS method were combined using the vortex vibration and centrifugation functions of the automated QuEChERS sample preparation system. The operating parameters and pretreatment steps were optimized, and the analytes were detected in the multiple reaction monitoring (MRM) mode. The quantification analysis was performed by the matrix-matched external standard method. The automated and the manual QuEChERS methods were compared from the methodological verification standpoint. The calibration curves showed good linearity in a certain range, and the correlation coefficients (R2) were greater than 0.99. The limits of detection and limits of quantification were 0.76-3.60 µg/kg and 2.28-10.80 µg/kg, respectively. Moreover, the recoveries ranged from 53.0% to 125.2%, and the relative standard deviations (RSDs) were less than 1.59% (n=5). The results obtained by the manual QuEChERS method were not significantly different from those obtained by the automated QuEChERS method. This method can effectively reduce the labor intensity and probability of error in the determination of pesticide residues.


Assuntos
Contaminação de Alimentos/análise , Resíduos de Praguicidas/análise , Verduras/química , Cromatografia Líquida de Alta Pressão , Extração em Fase Sólida , Espectrometria de Massas em Tandem
7.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3287-3296, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602885

RESUMO

To evaluate the pesticide residue risk of Jinyinhua Formula Granules( made from Lonicerae Japonicae Flos) used in the market preliminarily,20 samples of Jinyinhua Formula Granules from 5 manufactures were collected randomly through the national evaluative sampling test program. Totally 262 pesticides( involving 270 chemical monomers) with monitoring significance to traditional Chinese medicinal materials were detected. Samples were extracted by high speed homogenate with acetonitrile as solvent. And their residues were analyzed by GC-MS/MS and LC-MS/MS in MRM mode. No less than 2 groups of characteristic ion pairs were adopted for qualitative detection,and the calibration curve method was used for quantitative detection. The results showed that 20 pesticides were detected in 20 batches of Jinyinhua Formula Granules,with an average of about 9 pesticides detected in every batch,but no restricted pesticide was detected. The detected pesticides were all at the trace level,which was far lower than the limit of the general food standard. Therefore,the safety risk was low in Jinyinhua Formula Granules. In this study,a screening method for pesticide residues in Jinyinhua Formula Granules was established for the first time. The method was accurate and rapid,and the detection indicators were highly targeted. The results could provide theoretical reference for the prevention and control of pesticide safety risks in Jinyinhua Formula Granules and even traditional Chinese medicine formula granules.


Assuntos
Contaminação de Medicamentos , Medicamentos de Ervas Chinesas/análise , Resíduos de Praguicidas/análise , Cromatografia Gasosa , Cromatografia Líquida , Controle de Qualidade , Espectrometria de Massas em Tandem
8.
Artigo em Inglês | MEDLINE | ID: mdl-31535952

RESUMO

In this study, we propose an improved analytical method for the multiresidue analysis of captan (plus its metabolite, tetrahydrophthalimide), folpet (plus its metabolite, phthalimide), captafol, and iprodione in cereals using liquid chromatography tandem mass spectrometry (LC-MS/MS). As captan, captafol, and folpet are easily degraded during homogenisation and extraction, samples were comminuted with liquid nitrogen, and both QuEChERS and ethyl acetate-based extraction workflows provided a satisfactory method performance. The optimised LC-MS/MS procedure with electrospray ionisation did not degrade these compounds, and offered sufficient method selectivity by resolving and minimising co-eluting matrix-derived interferences. The method also resolved the problem of non-specific mass spectra that these compounds usually produce on GC-MS analysis involving electron ionisation. The method performance was satisfactory for all 6 compounds at 0.01 mg kg-1 and higher levels of fortification, and validated as per the SANTE/11813/2017 guidelines of analytical quality control in a wide range of cereals including rice, wheat, sorghum, and corn. The method provides special advantage of simultaneous analysis of captan, and folpet along with their metabolites (tetrahydrophthalimide, and phthalimide, respectively) in combination with captafol, and iprodione in a single chromatographic run. Although iprodione is known to degrade to 3,5-dichloroaniline, since this metabolite is not a part of the residue definition, it was not included in the scope of this method. As the method demonstrates satisfactory selectivity, sensitivity, accuracy, precision, and robustness in a wide range of cereal matrices, it is recommended for regulatory testing of these compounds in cereals.


Assuntos
Aminoimidazol Carboxamida/análogos & derivados , Captana/análogos & derivados , Captana/análise , Cicloexenos/análise , Contaminação de Alimentos/análise , Hidantoínas/análise , Resíduos de Praguicidas/análise , Ftalimidas/análise , Aminoimidazol Carboxamida/análise , Cromatografia Líquida , Grão Comestível/química , Análise de Alimentos , Espectrometria de Massas em Tandem
9.
J Agric Food Chem ; 67(33): 9203-9209, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31369261

RESUMO

With the monitoring of hundreds of pesticides in food and feed, the comminution step is equally crucial as any other to achieve valid results. However, sample processing is often underestimated in its importance and practical difficulty to produce consistent test portions for analysis. The scientific literature is rife with descriptions of microextraction methods, but ironically, sample comminution is often ignored or dismissed as being prosaic, despite it being the foundation upon which the viability of such techniques relies. Cryogenic sample processing using dry ice (-78 °C) is generally accepted in practice, but studies have not shown it to yield representative test portions of <1 g. Remarkably, liquid nitrogen has rarely been used as a cryogenic agent in pesticide residue analysis, presumably as a result of access, cost, and safety concerns. However, real-world implementation of blending unfrozen bulk food portions with liquid nitrogen (-196 °C) using common food processing devices has demonstrated this approach to be safe, simple, fast, and cost-effective and yield high-quality results for various commodities, including increased stability of labile or volatile analytes. For example, analysis of dithiocarbamates as carbon disulfide has shown a significant increase of thiram recoveries (up to 95%) using liquid nitrogen during sample comminution. This perspective is intended to allay concerns among working laboratories about the practical use of liquid nitrogen for improved sample processing in the routine monitoring of pesticide residues in foods and feeds, which also gives promise for feasible test sample size reduction in high-throughput miniaturized methods.


Assuntos
Ração Animal/análise , Contaminação de Alimentos/análise , Liofilização/métodos , Resíduos de Praguicidas/análise , Gelo-Seco , Liofilização/instrumentação , Frutas/química , Nitrogênio/química
10.
Anal Bioanal Chem ; 411(26): 6913-6929, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31418049

RESUMO

A method was developed for the analysis of 22 antiparasitic residues belonging to the benzoylurea, organophosphate, pyrimidinamine, pyrethrin and pyrethroid classes in salmon by liquid chromatography coupled with tandem mass spectrometry. Samples were extracted with acetonitrile-water as the extraction solvent with use of a vibrational shaking apparatus with a ceramic homogenizer. After extraction, the acetonitrile extracts were cleaned up by incubation at low temperature (-20 °C, 1 h) to remove fat, followed by dispersive solid-phase extraction using Z-Sep+ and primary-secondary amine as sorbents. Validation was performed following the 2002/657/EC and SANTE/11813/2017 guidelines. The trueness of the method ranged from 87% to 121% and precision ranged from 4.1% to 23.7%, with the exception of cyphenothrin, dicyclanil and azamethiphos. The method developed is particularly advantageous because the use of a vibrational shaker allows unattended extraction of samples and eliminates a laborious tissue disruption step, which increases sample throughput in the laboratory. The sample preparation and chromatographic separations can be performed in 5 and 4 h, respectively, for 36 samples. Graphical abstract.


Assuntos
Antiparasitários/análise , Praguicidas/análise , Alimentos Marinhos/análise , Animais , Cromatografia Líquida de Alta Pressão/métodos , Resíduos de Drogas/análise , Peixes/metabolismo , Análise de Alimentos/métodos , Limite de Detecção , Resíduos de Praguicidas/análise , Salmão/metabolismo , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos
11.
Food Chem ; 301: 125216, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31404804

RESUMO

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.


Assuntos
Cromatografia Líquida/métodos , Contaminação de Alimentos/análise , Frutas/química , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Verduras/química , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/análise , Captana/análogos & derivados , Captana/análise , Cicloexenos/análise , Hidantoínas/análise , Limite de Detecção , Ftalimidas/análise
12.
Sci Total Environ ; 687: 712-719, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31412474

RESUMO

To assess the health risk posed by flumethrin residues in beeswax to honeybees and honey consumers, 124 wax samples randomly distributed in Belgium were analysed for flumethrin residues using liquid chromatography/tandem mass spectrometry. The risk posed by flumethrin residues in beeswax to honeybee health was assessed through the calculation of a non-pondered and a pondered Hazard Quotient by the prevalence rate of flumethrin considering an oral or topical exposure. No statistical difference was found when comparing both the average flumethrin residues concentrations and contact and oral pondered hazard quotients between apiaries with lower and equal or higher than 10% of colony loss. Flumethrin residues estimated daily intake by Belgian consumers through honey and wax ingestion was estimated via a deterministic (worst-case scenario) and a probabilistic approach. The probabilistic approach was not possible for beeswax consumption due to the lack of individual consumption data. The highest estimated exposure was <0.1% of the theoretical maximum daily intake for both approaches, meaning no risk for human health.


Assuntos
Exposição Dietética/análise , Resíduos de Praguicidas/análise , Piretrinas/análise , Ceras/química , Animais , Abelhas , Bélgica , Exposição Dietética/estatística & dados numéricos , Humanos
13.
J Agric Food Chem ; 67(35): 9942-9949, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31403785

RESUMO

We develop an ultrasensitive T2-mediated immunosensor based on the coordination chemistry and Cu(I)-catalyzed 1,3-dipolar cycloaddition of azide andalkyne (CuAAC) and apply it for the detection of pesticide residues. We functionalize polyglutamic acid (PGA) on polystyrene to form a brush-like nanostructure that has a large loading capacity of Cu(II) through the coordination chemistry between PGA and Cu(II). Such a brush-like nanostructure could be used to chelate Cu(II) to modulate the CuAAC between azide-functionalized 1000 nm polystyrene (PS1000) and alkyne-functionalized 30 nm magnetic nanoparticles (MNP30), and the MNP30-PS1000 conjugate as a product of CuAAC can act as a magnetic probe in this T2-based immunosensor. This click chemistry and coordination chemistry-mediated immunosensor allows for an ultrasensitive detection for chlorpyrifos residue (0.022 ng/mL), a 58-fold enhancement compared with that of enzyme-linked immunosorbent assay (1.28 ng/mL), providing a promising platform for detection of trace small molecules.


Assuntos
Técnicas Biossensoriais/métodos , Clorpirifos/análise , Nanoestruturas/química , Resíduos de Praguicidas/análise , Alquinos/química , Azidas/química , Técnicas Biossensoriais/instrumentação , Quelantes/química , Química Click , Cobre/química , Água Potável/análise , Lagos/análise , Ácido Poliglutâmico/química , Sensibilidade e Especificidade , Poluentes da Água/análise
14.
Environ Monit Assess ; 191(9): 584, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31440848

RESUMO

A micro-liquid-liquid extraction (MLLE) technique coupled with liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis was established and validated to determine the residues of two macrocyclic lactone insecticides (spinetoram and spinosad) in green onion. The limit of quantification (LOQ) of the method, as demonstrated by the lowest acceptable recovery level, was 0.01 mg kg-1, and the obtained recoveries were 78.3-93.4% with relative standard deviations (RSDs) < 12.5%. The method was then applied for analyzing field samples collected after treatment with the tested insecticides under Egyptian open-field condition. The decline pattern, terminal residues, and dietary risk assessment of spinetoram and spinosad residues in green onion were evaluated for food safety. Spinetoram and spinosad residues' decline in green onion followed first-order kinetics with the half-lives of 1.2 and 1.42 days, respectively. Based on the results, the required period to reach their respective maximum residue limits (MRLs) was 1 and 0 days for spinetoram and spinosad residues in green onion, respectively, which indicates a short persistence level and high degradation rate. The results suggest that there is no unacceptable chronic or acute risk to human health from the consumption of green onion treated with spinetoram and spinosad according to the uses considered.


Assuntos
Inseticidas/análise , Macrolídeos/análise , Cebolas/química , Resíduos de Praguicidas/análise , Cromatografia Líquida/métodos , Combinação de Medicamentos , Egito , Monitoramento Ambiental , Meia-Vida , Lactonas , Microextração em Fase Líquida , Medição de Risco , Espectrometria de Massas em Tandem/métodos
15.
Anal Chim Acta ; 1078: 142-150, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31358212

RESUMO

Mycotoxins and pesticides are prevalent in cereal food. It is difficult to detect these two kinds of hazard factors simultaneously in rapid assay. In order to find a solution to the problem, carbamates and aflatoxins were selected in this study to establish a rapid, on-site, and quantitative paper sensor. Two novel monoclonal antibodies (mAbs) against carbaryl and carbofuran (1D2 and G11) were developed. The IC50 values (half maximal inhibitory concentration) were 0.8 ng/mL and 217.6 ng/mL for carbaryl and carbofuran, respectively. Based on the sensitive and specific mAbs, a multi-TRFICA (time-resolved fluorescence) paper sensor was developed, which simultaneously detected six types of hazardous chemicals, including AFB1, AFB2, AFG1, AFG2, carbaryl, and carbofuran. A universal sample pretreatment method for mycotoxins and pesticides was explored to apply on established competitive indirect enzyme-linked immunosorbent assay (icELISA) and multi-TRFICA-paper sensor. The established paper sensor can be easily observed with naked eyes, qualitatively under a UV lamp, and quantitated using a home-made device. It exhibited a calculated limit of quantity for AFTs, carbaryl, and carbofuran of 0.03, 0.02, and 60.2 ng/mL in corn samples, respectively. The spiking-recoveries and real sample studies proved that multi-TRFICA-paper sensor is an accurate, sensitive, and high throughput detection method for simple and low-cost analysis in corn samples.


Assuntos
Aflatoxinas/análise , Ensaio de Imunoadsorção Enzimática/métodos , Papel , Resíduos de Praguicidas/análise , Anticorpos Monoclonais/imunologia , Carbaril/imunologia , Carbofurano/imunologia , Európio/química , Fluorescência , Contaminação de Alimentos/análise , Nanopartículas Metálicas/química , Zea mays/química
16.
Food Chem ; 298: 125050, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260955

RESUMO

An analytical method involving QuEChERS (quick, easy, cheap, effective, rugged, and safe) sample preparation, followed by LC-MS/MS and GC-MS/MS was developed and validated for the determination of 60 pesticides in eggs. Recoveries of 70-120% were achieved for selected pesticides and relative standard deviations <20% were obtained for most analytes at three concentrations. The limit of quantification was <10 µg kg-1 for 83% of the total pesticides. This method was used to analyze 58 egg samples and the residues of seven pesticides (disulfoton, fipronil sulfone, cyromazine, o,p-DDT, p,p-DDD, p,p-DDT, and permethrin) were quantified in 16 egg samples at levels of 5-10 µg kg-1, which was below the corresponding the maximum residue levels, as established by Korean Ministry of Food and Drug Safety. We demonstrated that LC-MS/MS and GC-MS/MS in combination with QuEChERS can be used to routinely monitor multiple pesticide residues in egg samples.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Animais , Galinhas , Cromatografia Líquida de Alta Pressão , Dissulfóton/análise , Ovos/análise , Feminino , Limite de Detecção , Pirazóis/análise , Reprodutibilidade dos Testes
17.
Zhongguo Zhong Yao Za Zhi ; 44(11): 2197-2207, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31359642

RESUMO

The excessive pesticide residues and heavy metals in traditional Chinese medicine seriously endanger human health and the sustainable development of Chinese medicine industry. In order to improve the quality of traditional Chinese medicine and establish a general standard for maximum residue limits(MRL) of pesticides in pollution-free traditional Chinese medicine and decoction pieces, and to ensure the safety of clinical medication from its origin, MRLs were calculated based on the formula(MRL=A×W/100M) from Chinese Pharmacopeia, comparing it with the current Chinese and international standards as well as literature review, the RAND/UCLA appropriateness method(RAM) was applied to determine the categories and MRLs of pesticides in pollution-free traditional Chinese medicine and decoction pieces. Two questionnaires were drafted for expert panel and appropriateness analysis was carried out with the 9-point Likert scale to determine the general standard for MRLs of pollution-free traditional Chinese medicine and decoction pieces. The results showed that a total of nine experts from different fields scored the necessity of standard-setting and 206 pesticide residue limits respectively. The appropriateness scores of 206 pesticides were greater than 7, and appropriateness rate was 100%, which signifies that the expert panel has reached consensus. In summary, based on the RAM, the general standard for maximum residue limits of pesticides in pollution-free Chinese medicines and decoction pieces has reached an expert consensus. Comparing with the MRLs of medicinal plants and plant-sourced food from CAC, Europe Union, the United States, South Korea, Japan, Australia, New Zealand and Canada, 206 MRLs from this general standard share 88.8% in common, 4.4% of which is higher and 6.8% lower than those international standards. This has provided a basis for standardizing the use of pesticides in pollution-free traditional Chinese medicine.


Assuntos
Medicamentos de Ervas Chinesas/normas , Resíduos de Praguicidas/análise , Praguicidas/análise , Medicina Tradicional Chinesa
18.
Se Pu ; 37(7): 729-734, 2019 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-31271012

RESUMO

A method was developed for the determination of chlorpyrifos residues in paddy field aquatic products by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Samples were extracted with acetonitrile and purified by using 0.2 g primary secondary amine (PSA) sorbent and 1.2 g MgSO4. The target compound was separated on a Hypersil GOLD C18 column (100 mm×2.1 mm, 5 µm), and was determined using a heated electrospray ionization (HESI) source in the positive ion selective reaction monitoring (SRM) mode. The analyte was quantified with external standard using the matrix-matched standard calibration curve method. The results showed that good linearities were obtained in the range of 0.5-100.0 µg/L, and the correlation coefficients were greater than 0.999. The spiked recoveries of chlorpyrifos ranged from 86.2% to 103.6% with RSDs of 3.5%-7.6% (n=6). The limits of detection and quantification were 0.25 µg/kg and 0.5 µg/kg, respectively. This method is simple, quick, sensitive, and suitable for the rapid determination and analysis of chlorpyrifos residues in paddy field aquatic products.


Assuntos
Clorpirifos/análise , Resíduos de Praguicidas/análise , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Oryza , Espectrometria de Massas em Tandem
19.
Food Chem ; 299: 125123, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31299514

RESUMO

Beehive products are considered sentinels for environmental pollutants. The presence of trace elements and pesticides in honey and beeswax may pose a health hazard to consumers. The study's aim was to determine the profile of pesticides and trace elements in Israeli honey and beeswax samples in relation to human risk assessment. At least two pesticides contaminated the honey and beeswax samples simultaneously, in which, amitraz metabolites and coumaphos were frequently detected. The neonicotinoid insecticides and 2,4-dichlorophenoxyacetic acid, were found only in honey samples, whereas the more lipophilic pesticides were predominantly found in beeswax. In honey, chromium displayed the highest mean concentration, followed by zinc, whereas lead and molybdene occurred only in beeswax. Our findings indicate that the daily consumption of honey and beeswax together may compromise children's health. Sucrose-syrup fed honey could not be distinguished from floral honey based on sugar profile, rather by its trace elements levels.


Assuntos
Poluentes Ambientais/análise , Mel/análise , Resíduos de Praguicidas/análise , Oligoelementos/análise , Ceras/análise , Ácido 2,4-Diclorofenoxiacético/análise , Animais , Abelhas , Cromo/análise , Cromo/toxicidade , Contaminação de Alimentos/análise , Herbicidas/análise , Mel/normas , Humanos , Inseticidas/análise , Israel , Resíduos de Praguicidas/toxicidade , Praguicidas/análise , Medição de Risco , Açúcares/análise , Toluidinas/análise , Oligoelementos/toxicidade , Ceras/normas
20.
Food Chem ; 300: 125220, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31352288

RESUMO

Fruits and vegetables play an important role in human nutrition. Study of the contamination sources which result from farming activities is of importance. For this reason, a chitosan-graphene oxide nanocomposite film was prepared and implemented as the extractive phase in thin film microextraction of six organophosphate residues (OPPs) in the samples using high-performance liquid chromatography. The optimized method was validated and the limits of detection (0.7-1.2 µg l-1), limits of quantification (2.3-4.0 µg l-1) and linear dynamic range (2.0-1000.0 µg l-1) were obtained. Principal component analysis revealed clustering of the fruit and vegetable samples based on the selected (OPPs) into two groups of unwashed-unpeeled and peeled-washed. This mapping was further investigated using descriptive method of boxplot. Washing and peeling of the samples, reduced the presence of OPPs to half or one third of interquartile range found in the unpeeled and unwashed samples.


Assuntos
Contaminação de Alimentos/análise , Frutas/química , Organofosfatos/análise , Resíduos de Praguicidas/análise , Verduras/química , Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Análise de Alimentos/estatística & dados numéricos , Grafite/química , Limite de Detecção , Nanoestruturas/química , Óxidos/química , Análise de Componente Principal , Reprodutibilidade dos Testes , Microextração em Fase Sólida/instrumentação , Microextração em Fase Sólida/métodos
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