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1.
Food Addit Contam Part B Surveill ; 16(4): 321-331, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37581338

RESUMO

Upward trend in the use of food supplements urged the assessment of their safety. Eighty-eight liquid herbal supplements collected in Novi Sad (Serbia) in 2018 (36 samples) and 2021 (52 samples) were analysed for the presence of benzoates and sorbates (HPLC-UV) and benzene (HS-GC/MS). Benzoic acid varied from 599 to 9253 mg/kg and sorbic acid between 185 and 1658 mg/kg. The acceptable daily intake of sorbic acid was not reached, but in case of benzoic acid, it was exceeded by 5.3% of the samples. The presence of benzene was confirmed in 41.2% of benzoate preserved supplements (0.9-51.7 µg/kg). Benzene exposure revealed no health concern: maximum hazard quotients ranged from 0.39% (toddlers) to 0.84% (adolescents); minimum margins of exposure were between 35,680 (adolescents) and 77,419 (toddlers); estimates of lifetime cancer risk did not reach one extra cancer case per 100 000 persons. However, measures to mitigate benzene presence in food should be considered.


Assuntos
Benzoatos , Neoplasias , Adolescente , Humanos , Benzoatos/análise , Benzeno/análise , Contaminação de Alimentos/análise , Ácido Sórbico , Ácido Benzoico/análise , Suplementos Nutricionais/análise , Medição de Risco
2.
Food Chem ; 274: 429-433, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30372961

RESUMO

This study reports a method for propoxycarbazone pesticide determination including its metabolite in food commodities (lettuce, beetroot, soybean meal and honey). Both compounds were extracted, and samples cleaned using a buffered QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method based on the AOAC Official Method, followed by ultra high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). Both matrix-matched calibration curves showed good linearity (R2 = 0.99) within the tested ranges. Method performance was assessed on the basis of recovery and intra/inter-day precision studies at spiked concentrations of 10 (25) and 50 µg/kg (n = 5). Mean recovery rates were between 73 and 110%, while precision studies, assessed by relative standard deviation (RSD), were ≤20%. The limits of quantification (LOQ) were established as 10 or 25 µg/kg, depending on the matrix, which are low enough for monitoring residues at regulated maximum residue levels.


Assuntos
Benzoatos/análise , Benzoatos/metabolismo , Custos e Análise de Custo , Análise de Alimentos/economia , Análise de Alimentos/métodos , Segurança , Espectrometria de Massas em Tandem , Triazóis/análise , Triazóis/metabolismo , Calibragem , Cromatografia Líquida de Alta Pressão , Contaminação de Alimentos/análise , Modelos Lineares
3.
Talanta ; 151: 42-50, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26946008

RESUMO

Pyrethroid insecticides are used extensively in agriculture, and they, as well as their environmental degradates, may remain as residues on foods such as fruits and vegetables. Since pyrethroid degradates can be identical to the urinary markers used in human biomonitoring, it is important to understand the contribution of these degradates when studying sources of human pyrethroid exposure. We modified the widely used Quick Easy Cheap Effective Rugged Safe (QuEChERS) method to measure several current-use pyrethroids (cis/trans-permethrin, cypermethrin, deltamethrin, esfenvalerate, bifenthrin, cyfluthrin, and cyhalothrin) and their environmental degradation products (3-PBA, cis/trans-DCCA, 4-F-3-PBA, DBCA, and MPA) in selected fresh fruits and vegetables. Using fortified samples, we determined extraction efficiencies from: tomatoes, oranges (whole, peeled, and rind), grapes, apples, bananas (peeled and rind only), onions, lettuce, green peppers, carrots and broccoli. For a subset of these food items (apples, grapes, tomatoes, lettuce and banana peel), we also established limits of detection (MDLs) and quantitation (MQLs). Each sample was homogenized (1kg) then spiked with the target pyrethroids and their degradation products. Sub-samples (15g) were extracted with acetonitrile, then salted out and partitioned with NaCl and MgSO4. The extract was divided and further cleaned using solid phase extraction (SPE) cartridges containing either graphitized non-porous carbon (pyrethroids) or C18 (degradation products). Sample analysis was via liquid chromatography/tandem mass spectrometry (LC-MS/MS). Considering the mean recoveries each of the 14 analytes in all 13 matrices: 42% of the recoveries were ≥90%, 70% were ≥80%, and 90% were ≥70%. All MDL's were less than 100ng/kg, except 3-PBA (132ng/kg, tomato), MPA (129ng/kg, tomato), and trans-permethrin (141ng/kg, banana peel). We then applied the method to non-spiked samples (subset of 5 for which the MDLs/MQLs had been determined) collected weekly for four weeks from local supermarkets. At least one pyrethroid was present in measureable concentrations in all matrices except banana peels. In contrast, the only degradation products detected were cis/trans-DCCA, in one lettuce sample.


Assuntos
Benzoatos/análise , Frutas/química , Piretrinas/análise , Verduras/química , Adulto , Benzoatos/química , Benzoatos/isolamento & purificação , Biodegradação Ambiental , Cromatografia Líquida/métodos , Análise Custo-Benefício , Exposição Ambiental/análise , Exposição Ambiental/prevenção & controle , Monitoramento Ambiental/economia , Monitoramento Ambiental/métodos , Humanos , Inseticidas/análise , Inseticidas/química , Inseticidas/isolamento & purificação , Pessoa de Meia-Idade , Estrutura Molecular , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/isolamento & purificação , Resíduos de Praguicidas/metabolismo , Piretrinas/química , Piretrinas/isolamento & purificação , Reprodutibilidade dos Testes , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Adulto Jovem
4.
Forensic Sci Int ; 251: 107-14, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25898183

RESUMO

In recent years, the high frequency of illicit substance abuse reported in the United States has made the development of efficient and rapid detection methods important. Biological detectors, such as canines (Canis familiaris), are valuable tools for rapid, on-site identification of illicit substances. However, research indicates that in many cases canines do not alert to the contraband, but rather to the volatile organic compounds (VOCs) that are released from the contraband, referred to as the "active odor." In 2013, canine accuracy and reliability were challenged in the Supreme Court case, State of Florida v. Jardines. In this case, it was stated that if a canine alerts to the active odor, and not the contraband, the canine's accuracy and selectivity could be questioned, since many of these compounds have been found in common household products. Specifically, methyl benzoate, the active odor of cocaine, has been found to be the most abundant compound produced by snapdragon flowers. Therefore, the purpose of this study is to evaluate the odor profiles of various species of snapdragon flowers to assess how significantly methyl benzoate contributes to the total VOC profile or fragrance that is produced. Particularly, this study examines the VOCs released from newly grown snapdragon flowers and determines its potential at eliciting a false alert from specially trained detection canines. The ability of detection canines to differentiate between cocaine and snapdragon flowers was determined in order to validate the field accuracy and discrimination power of these detectors. An optimized method using headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME/GC-MS) was used to test the different types and abundances of compounds generated from snapdragon flowers at various stages throughout the plants' life cycle. The results indicate that although methyl benzoate is present in the odor profile of snapdragon flowers, other compounds are present that contribute significantly, if not more, than that of methyl benzoate. Canine teams, from various police departments throughout South Florida, certified for narcotics detection, took part in this study. Two canine trials involving 21 canines teams were performed by exposing the teams to 4 different species of snapdragon flowers. Of the 21 canine teams tested, none alerted to the snapdragon flowers presented, while all (100%) alerted to real cocaine samples, the positive control. Notably, the results revealed that although methyl benzoate is produced by snapdragon flowers, certified narcotics detection canines can distinguish cocaine's odor profile from that of snapdragon flowers.


Assuntos
Antirrhinum/química , Benzoatos/análise , Cães/fisiologia , Flores/química , Olfato/fisiologia , Compostos Orgânicos Voláteis/análise , Animais , Comportamento Animal/fisiologia , Cocaína/química , Ciências Forenses , Cromatografia Gasosa-Espectrometria de Massas , Entorpecentes/química , Odorantes , Microextração em Fase Sólida
5.
Artigo em Inglês | MEDLINE | ID: mdl-24321757

RESUMO

A novel analytical approach based on molecularly imprinted solid phase extraction (MISPE) coupled with dispersive liquid-liquid microextraction (DLLME), and injector port silylation (IPS) has been developed for the selective preconcentration, derivatization and analysis of 3-phenoxybenzoic acid (3-PBA) using gas chromatography-tandem mass spectrometry (GC-MS/MS) in complex biological samples such as rat blood and liver. Factors affecting the synthesis of MIP were evaluated and the best monomer and cross-linker were selected based on binding affinity studies. Various parameters of MISPE, DLLME and IPS were optimized for the selective preconcentration and derivatization of 3-PBA. The developed method offers a good linearity over the calibration range of 0.02-2.5ngmg(-1) and 7.5-2000ngmL(-1) for liver and blood respectively. Under optimized conditions, the recovery of 3-PBA in liver and blood samples were found to be in the range of 83-91%. The detection limit was found to be 0.0045ngmg(-1) and 1.82ngmL(-1) in liver and blood respectively. SRM transition of 271→227 and 271→197 has been selected as quantifier and qualifier transition for 3-PBA derivative. Intra and inter-day precision for five replicates in a day and for five, successive days was found to be less than 8%. The method developed was successfully applied to real samples, i.e. rat blood and tissue for quantitative evaluation of 3-PBA. The analytical approach developed is rapid, economic, simple, eco-friendly and possess immense utility for the analysis of analytes with polar functional groups in complex biological samples by GC-MS/MS.


Assuntos
Benzoatos/análise , Benzoatos/sangue , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Líquida/métodos , Fígado/química , Impressão Molecular , Animais , Cromatografia Gasosa-Espectrometria de Massas/economia , Limite de Detecção , Microextração em Fase Líquida/economia , Ratos , Ratos Wistar , Espectrometria de Massas em Tandem/economia , Espectrometria de Massas em Tandem/métodos
6.
Artigo em Inglês | MEDLINE | ID: mdl-24779907

RESUMO

From 2008 to 2011, surveys were conducted to determine the levels of benzoic and sorbic acids and their respective salts in 983 retail food samples which included sauces, vegetable and fruit preparations, flavoured syrups, food supplements, cereals, bakery products, jelly, synthetic cream, sprays, mustards, jam and preserves, molasses, chewing gum, confectionery, non-alcoholic beverages, tea, wine, vinegar, brine and beers. The analysis involved methanol extraction of the foodstuff and direct determination by HPLC with UV detection. Quality assurance was employed with each batch of samples. Accuracy was ensured through regular participation in proficiency tests. Over this four-year period, a total of 23 samples (2.3%), some syrups, tomato sauces and fruit contained individual or combined levels of sorbic and benzoic acids above regulatory limits. Unauthorised use of benzoic acid was also detected in a syrup sample, bakery products and fruit preserves.


Assuntos
Benzoatos/análise , Bebidas/análise , Doces/análise , Inspeção de Alimentos/métodos , Conservantes de Alimentos/análise , Alimentos em Conserva/análise , Ácido Sórbico/análise , Bebidas/economia , Calibragem , Doces/economia , Cromatografia Líquida de Alta Pressão , Condimentos/análise , Condimentos/economia , Suplementos Nutricionais/análise , Suplementos Nutricionais/economia , Alimentos em Conserva/economia , Frutas/química , Fidelidade a Diretrizes , Política de Saúde , Promoção da Saúde , Humanos , Limite de Detecção , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta , Turquia
7.
Anal Bioanal Chem ; 402(6): 2173-82, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22209957

RESUMO

A rapid ultra-high-performance liquid chromatographic-tandem mass spectrometric (UHPLC-MS-MS) method has been developed for rapid screening and quantitative analysis of sulfonate derivatives (SDs) in commercial white peony root. Separation was performed on an Agilent Zorbax Eclipse Plus-C18 column by gradient elution with acetonitrile-0.1% (v/v) formic acid as the mobile phase. In-source fragmentation was used to generate the characteristic fragment ion at m/z 259 and to screen for nine SDs. Detection of these SDs was further performed in multiple reaction monitoring (MRM) mode to improve sensitivity and to quantify the two SDs paeoniflorin sulfonate and benzoylpaeoniflorin sulfonate. The method was validated for specificity, linearity, limits of detection and quantification, precision, accuracy, and matrix effects. Nine commercial white peony root samples were examined by use of this method, which revealed great variety in the paeoniflorin sulfonate and benzoylpaeoniflorin sulfonate content.


Assuntos
Alcanossulfonatos/análise , Paeonia/química , Extratos Vegetais/análise , Espectrometria de Massas em Tandem/métodos , Benzoatos/análise , Hidrocarbonetos Aromáticos com Pontes/análise , Cromatografia Líquida de Alta Pressão/economia , Cromatografia Líquida de Alta Pressão/métodos , Glucosídeos/análise , Monoterpenos , Raízes de Plantas/química , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem/economia
8.
Bull Environ Contam Toxicol ; 81(5): 494-7, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18777146

RESUMO

Methyl benzoate - as a biomarker for mold growth - was used as a specific target compound to indicate outgassed MVOC products from mold. Both real and surrogate samples were analyzed from a variety of matrices including: carpet, ceiling tiles, dried paint surfaces, wallboard and wallboard paper. Sampling parameters, including: desorption, extraction time, incubation temperature, pH, salt effects and spinning rate, were optimized. Results suggest that extraction and detection of methyl benzoate amongst other MVOCs can be accomplished cleanly by SPME-GC/MS methods. With detection limits (LOD = 1.5 ppb) and linearity (0.999) over a range of 100 ppm to 2 ppb, this work demonstrates that such a green technique can be contemplated for use in quick assessment or as part of an ongoing assessment strategy to detect mold growth in common indoor buildings and materials for both qualitative and quantitative determinations. Of importance, no matrix effects are observed under optimized extraction conditions.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Benzoatos/análise , Materiais de Construção/análise , Fungos/química , Biomarcadores/análise , Calibragem , Cromatografia Gasosa-Espectrometria de Massas , Reprodutibilidade dos Testes , Microextração em Fase Sólida , Solventes
9.
Food Addit Contam ; 20(2): 127-35, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12623660

RESUMO

A study was performed to evaluate the estimated daily intakes (EDI) of benzoates for the average and high (90th percentile) consumers by age and sex categories in Korea. The estimation of daily intakes of benzoates was based on individual dietary intake data from the National Health and Nutrition Survey in 1998 and on the determination of benzoates in eight food categories. The EDI of benzoates for average consumers of different age groups ranged from 0.009 to 0.025 mg kg(-1) bw day(-1). For high consumers, the range of EDI of benzoates was 0.195-1.878 mg kg(-1) bw day(-1). The intakes represented 0.18-0.50% of the acceptable daily intake (ADI) of benzoates for average consumers and 3.9-37.6% of the ADI for high consumers. Foods that contributed most to the daily intakes of benzoates were mixed beverages and soy sauce in Korea.


Assuntos
Benzoatos/administração & dosagem , Conservantes de Alimentos/administração & dosagem , Adolescente , Adulto , Distribuição por Idade , Idoso , Aloe , Benzoatos/análise , Bebidas/análise , Criança , Pré-Escolar , Condimentos/análise , Ingestão de Energia , Comportamento Alimentar , Feminino , Humanos , Lactente , Coreia (Geográfico) , Masculino , Pessoa de Meia-Idade , Panax , Distribuição por Sexo
10.
Ecotoxicol Environ Saf ; 23(2): 161-72, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1374324

RESUMO

An international ring test involving 14 laboratories was organized on behalf of the Commission of the European Economic Communities (EEC) with the purpose of evaluating two proposed screening methods for assessment of biodegradability in seawater: (a) a shake flask die-away test based primarily on analysis of dissolved organic carbon and (b) a closed bottle test based on determination of dissolved oxygen. Both tests are performed with nutrient-enriched natural seawater as the test medium and with no inoculum added other than the natural seawater microflora. The test methods are seawater versions of the modified OECD screening test and the closed bottle test, respectively, adopted by the Organization for Economic Cooperation and Development (OECD) and by the EEC as tests for "ready biodegradability." The following five chemicals were examined: sodium benzoate, aniline, diethylene glycol, pentaerythritol, and 4-nitrophenol. Sodium benzoate and aniline, which are known to be generally readily biodegradable consistently degraded in practically all tests, thus demonstrating the technical feasibility of the methods. Like in previous ring tests with freshwater screening methods variable results were obtained with the other three compounds, which is believed primarily to be due to site-specific differences between the microflora of the different seawater samples used and to some extent also to differences in the applied concentrations of test material. A positive result with the screening methods indicates that the test substance will most likely degrade relatively rapidly in seawater from the site of collection, while a negative test result does not preclude biodegradability under environmental conditions where the concentrations of chemicals are much lower than the concentrations applied for analytical reasons in screening tests. Nevertheless, the screening tests are considered useful and cost-effective tools for an initial assessment of biodegradability in marine environments.


Assuntos
Água do Mar/análise , Poluentes Químicos da Água/análise , Compostos de Anilina/análise , Benzoatos/análise , Ácido Benzoico , Biodegradação Ambiental , Etilenoglicóis/análise , Nitrofenóis/análise , Propilenoglicóis/análise , Padrões de Referência
11.
Ecotoxicol Environ Saf ; 23(2): 173-90, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1374325

RESUMO

A comparative study has been performed on test methods for assessing the biodegradability of chemicals in seawater environments. A simple shake flask die-away test with natural seawater and 14C-labeled chemicals added in microgram/liter concentrations is proposed as a "simulation" test. The analytical parameter used in this test is residual dissolved 14C activity. The performance of the simulation test has been compared with the performance of similar screening tests with dissolved organic carbon analysis and test compounds added in mg/liter concentrations to nutrient-enriched seawater. All chemicals investigated that passed the screening tests were also degradable in the simulation test and some results with simulation tests were positive; even screening tests were negative, while some compounds, including maleinhydrazide, known to be degradable in soil, remained undegraded in either type of test. Disappearance times after the ended lag time were smaller in screening tests than in simulation tests, but the rates of biodegradation cannot be meaningfully compared, as zero-order kinetics in combination with an exponentially growing population of degraders prevail in screening tests, while first-order kinetics and frequently a constant activity of degraders (cooxidation) prevail in simulation tests where the test material is a secondary substrate only. In screening tests, lag times are sometimes excessively long and highly variable. Whether the lag times could be decreased and their variability narrowed by supplementation with a cosubstrate (yeast extract) or by inoculation with seawater that had been preadapted to the test material was investigated. In most experiments such test modifications had no significant effect but in one experiment with 4-nitrophenol, inoculation with 1% preadapted seawater decreased the lag phase from greater than 35 to 9 days.


Assuntos
Água do Mar/análise , Poluentes Químicos da Água/análise , Compostos de Anilina/análise , Benzoatos/análise , Ácido Benzoico , Biodegradação Ambiental , Etilenoglicóis/análise , Métodos , Nitrofenóis/análise , Propilenoglicóis/análise , Padrões de Referência
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