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1.
J Food Compost Anal ; 972021 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-35547641

RESUMEN

The 2018 Agricultural Improvement Act removed hemp from Schedule I control, creating a market for hemp products, including cannabidiol-containing products. Due to the market's rapid growth, little is known about the presence and concentration of cannabinoids in commercial products. Herein, 11 cannabinoids were quantified using liquid chromatography with diode-array detection in a non-representative sampling of 147 products labeled as containing hemp or cannabidiol. A subset of 133 products were analyzed for toxic elements using inductively coupled plasma-mass spectrometry. Cannabinoid content ranged from < LOD - 143 mg/serving, with a median of 16.7 mg/serving. Fewer than half of products surveyed contained cannabidiol concentrations within 20 % of their label declarations. The estimated exposure to lead was below the Interim Reference Level of 12.5 µg/day Pb for women of childbearing age, and most products presented concentrations of Δ9-tetrahydrocannabinol below LOQ. These findings emphasize the need for further testing and representative investigation of the cannabidiol marketplace.

2.
Artículo en Inglés | MEDLINE | ID: mdl-31437088

RESUMEN

Potential consumer exposure to nanoparticles (NPs) from nanoenabled food contact materials (FCMs) has been a driving force for migration studies of NPs from FCMs. Although NP migration from fresh, unused FCMs was not previously observed, conditions that result in significant changes to the surface of FCMs have not been investigated for NP migration into food. Therefore, a quantitative assessment of nanoparticle release from commercially available nanosilver-enabled FCMs was performed using an abrasion protocol to simulate cleaning, cutting, scraping and other stressful use conditions. Laser scanning confocal microscopy (LSCM) analysis showed a general increase in root mean square (RMS) roughness after FCM abrasion, and particle count (for particle sizes from 80 nm to 960 nm) at the surface was 4 orders of magnitude higher for the abraded FCMs. Migration was evaluated using both water and 3% (v/v, volume fraction) acetic acid as food simulants. Low concentrations of total Ag were detected in water simulants with a small portion (<10 ng dm-2) in the form of silver nanoparticles (AgNPs). Median particle diameter ranged from 39 nm to 50 nm with particle number concentrations on the order of 106 particles dm- 2. Total Ag migration into 3% (v/v) acetic acid was significantly higher than in water; however, 3% (v/v) acetic acid was not suitable for evaluation of NP release due to dissolution of AgNPs to Ag+ under acidic solution chemistries.


Asunto(s)
Contaminación de Alimentos/análisis , Embalaje de Alimentos , Nanopartículas del Metal/análisis , Plata/análisis , Agua/química
3.
Environ Toxicol Chem ; 38(4): 872-882, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30614049

RESUMEN

The bioavailability and bioaccumulation of sedimentary hydrophobic organic compounds (HOCs) is of concern at contaminated sites. Passive samplers have emerged as a promising tool to measure the bioavailability of sedimentary HOCs and possibly to estimate their bioaccumulation. We thus analyzed HOCs including organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), and polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) in sediment, porewater, and river water using low-density polyethylene passive samplers and in 11 different finfish species and blue crab from the lower Passaic River. In addition, perfluorinated alkyl acids (PFAAs) were measured in grab water samples, sediment, and fish. Best predictors of bioaccumulation in biota were either porewater concentrations (for PCBs and OCPs) or sediment organic carbon (PBDEs and PFAAs), including black carbon (OCPs, PCBs, and some PCDD/F congeners)-normalized concentrations. Measured lipid-based concentrations of the majority of HOCs exceeded the chemicals' activities in porewater by at least 2-fold, suggesting dietary uptake. Trophic magnification factors were >1 for moderately hydrophobic analytes (log octanol-water partitioning coefficient [KOW ] = 6.5-8.2) with low metabolic transformation rates (<0.01 d-1 ), including longer alkyl chain PFAAs. For analytes with lower (4.5-6.5) and higher (>8.2) KOW s, metabolic transformation was more important in reducing trophic magnification. Environ Toxicol Chem 2019;38:872-882. © 2019 SETAC.


Asunto(s)
Braquiuros/metabolismo , Monitoreo del Ambiente/métodos , Peces/metabolismo , Compuestos Orgánicos/análisis , Ríos/química , Contaminantes Químicos del Agua/análisis , Animales , Bioacumulación , Fluorocarburos/análisis , Fluorocarburos/metabolismo , Éteres Difenilos Halogenados/análisis , Éteres Difenilos Halogenados/metabolismo , Hidrocarburos Clorados/análisis , Hidrocarburos Clorados/metabolismo , Interacciones Hidrofóbicas e Hidrofílicas , New Jersey , Compuestos Orgánicos/metabolismo , Plaguicidas/análisis , Plaguicidas/metabolismo , Contaminantes Químicos del Agua/metabolismo
4.
Artículo en Inglés | MEDLINE | ID: mdl-33209188

RESUMEN

Potential consumer exposure to nanoparticles (NPs) from nanoenabled food contact materials (FCMs) has been a driving force for migration studies of NPs from FCMs. Although NP migration from fresh, unused FCMs was not previously observed, conditions that result in significant changes to the surface of FCMs have not been investigated for NP migration into food. Therefore, a quantitative assessment of nanoparticle release from commercially available nanosilver-enabled FCMs was performed using an abrasion protocol to simulate cleaning, cutting, scraping and other stressful use conditions. Laser scanning confocal microscopy (LSCM) analysis showed a general increase in root mean square (RMS) roughness after FCM abrasion, and particle count (for particle sizes from 80 nm to 960 nm) at the surface was 4 orders of magnitude higher for the abraded FCMs. Migration was evaluated using both water and 3% (v/v, volume fraction) acetic acid as food simulants. Low concentrations of total Ag were detected in water simulants with a small portion (<10 ng dm-2) in the form of silver nanoparticles (AgNPs). Median particle diameter ranged from 39 nm to 50 nm with particle number concentrations on the order of 106 particles dm- 2. Total Ag migration into 3% (v/v) acetic acid was significantly higher than in water; however, 3% (v/v) acetic acid was not suitable for evaluation of NP release due to dissolution of AgNPs to Ag+ under acidic solution chemistries.


Asunto(s)
Contaminación de Alimentos/análisis , Embalaje de Alimentos , Nanopartículas del Metal/análisis , Plata/análisis , Ácido Acético , Antiinfecciosos/análisis , Antiinfecciosos/toxicidad , Inocuidad de los Alimentos , Humanos , Nanopartículas del Metal/toxicidad , Microscopía Confocal , Nanocompuestos/análisis , Nanocompuestos/toxicidad , Tamaño de la Partícula , Plata/toxicidad , Propiedades de Superficie , Agua
5.
Artículo en Inglés | MEDLINE | ID: mdl-30352016

RESUMEN

Migration evaluation involving nano-enabled food contact materials (FCMs) mostly focuses on potential nanoparticle release from new unused products. This may not represent consumer use practices encountered by the FCMs in their lifecycle. In order to determine if product use impacts the release of nanoparticles or other FCM components, it is necessary to perform migration evaluations under typical consumer use scenarios. A quantitative assessment of nanoparticle release from a commercially available nanosilver-enabled cutting board was performed under five conditions intended to simulate consumer use. Knife motion, washing and scratching scenarios were simulated by linear abrasion using knife blades, scrubbing pads and tungsten carbide burr attachments, respectively. Migration was evaluated using water and 3% acetic acid as food simulants. Low concentrations of silver (Ag) were detected in water simulants, a small portion (<4 ng dm-2) in the form of silver nanoparticles (AgNPs) with particle number concentrations on the order of 106 particles dm-2. Median particle diameter was 40 nm. Nanoparticle release into water was observed under all five consumer use scenarios studied, however there was no correlation with the different levels of stress simulated.


Asunto(s)
Contaminación de Alimentos/análisis , Embalaje de Alimentos , Nanopartículas del Metal/análisis , Plata/análisis , Ácido Acético/química , Inocuidad de los Alimentos , Humanos , Tamaño de la Partícula , Propiedades de Superficie , Agua/química
6.
Artículo en Inglés | MEDLINE | ID: mdl-30130454

RESUMEN

4-Methylimidazole (4-MEI) is formed in caramel colours produced using ammonium compounds (Class III and Class IV caramel colours). 4-MEI can also form in food through Maillard reactions between reducing sugars and amino acids during cooking, roasting or dry-heating. The USFDA has analysed over 700 food and beverage samples collected from 2013 to 2015 for the presence of 4-MEI. These samples include foods containing added caramel colour and foods that are not labelled as containing added caramel colour, but which may contain 4-MEI resulting from thermal treatment. The 4-MEI levels in all food samples were quantified using LC-MS/MS. These data were used to develop a comprehensive dietary exposure assessment for 4-MEI for the U.S. population aged 2 years or more and several sub-populations, using two non-consecutive days of food consumption data from the combined 2009-2012 National Health and Nutrition Examination Survey and 10-14-day food consumption survey data for 2009-2012 from the NPD Group, Inc. National Eating Trends-Nutrient Intake Database. Dietary exposure estimates were prepared for each category of foods labelled as containing added caramel colour and of foods not labelled as containing added caramel colour, but which may contain 4-MEI from thermal treatment. Exposure to 4-MEI from consumption of foods containing added caramel colour was higher than that from foods that contain 4-MEI from thermal treatment for all population groups. Cola-type carbonated beverages were the highest contributors for most populations from foods containing added caramel colour. Coffee was the highest contributor for most populations from foods in which 4-MEI could be formed from thermal treatment. An overall combined exposure to 4-MEI was also estimated that included all foods identified as containing added caramel colour and foods in which 4-MEI could be formed by thermal treatment.


Asunto(s)
Dulces/análisis , Carbohidratos/química , Culinaria , Exposición Dietética/análisis , Contaminación de Alimentos/análisis , Imidazoles/análisis , Adolescente , Adulto , Niño , Preescolar , Humanos , Imidazoles/administración & dosificación , Lactante , Estructura Molecular , Temperatura , Estados Unidos , Adulto Joven
7.
Artículo en Inglés | MEDLINE | ID: mdl-27049753

RESUMEN

Research focused on assessing potential consumer exposure to nanoparticles released from nano-enabled food-contact materials (FCMs) has often reached conflicting conclusions regarding the detection of migrating nanoparticles. These conflicting conclusions, coupled with the potential for nanoparticles to be unstable in certain food simulants, has necessitated a closer look at the role played by food simulants recommended for use in nanoparticle migration evaluation. The influence of aqueous food simulants on nanoparticles under migration evaluation conditions is reported herein. The stability of silver nanoparticles (AgNP) spiked into three food simulants (water, 10% ethanol and 3% acetic acid) was investigated using asymmetric flow field-flow fractionation (AF4), ultrafiltration, electron microscopy (EM), and single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS). While 3% acetic acid induced significant oxidative dissolution of AgNP to silver ions, there were very minor to no changes in the physicochemical properties of AgNP in water and 10% ethanol.


Asunto(s)
Bebidas/análisis , Utensilios de Comida y Culinaria , Contaminación de Alimentos/prevención & control , Embalaje de Alimentos , Nanopartículas del Metal/análisis , Modelos Químicos , Plata/análisis , Ácido Acético/química , Difusión , Etanol/química , Fraccionamiento de Campo-Flujo , Cinética , Espectrometría de Masas , Ensayo de Materiales , Nanopartículas del Metal/química , Nanopartículas del Metal/toxicidad , Nanopartículas del Metal/ultraestructura , Microscopía Electrónica de Transmisión , Plata/química , Plata/toxicidad , Cloruro de Sodio/química , Solubilidad , Espectrofotometría Atómica , Ultrafiltración , Agua/química
8.
J Chromatogr A ; 1444: 106-13, 2016 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-27018189

RESUMEN

Cross-linked polyester resins are being introduced into the market as alternatives to epoxy resins as coatings for metal food cans. Identification of potential migrants, from these coatings into food, is a significant analytical challenge due to the diversity of substances employed in the manufacture of the coatings. However, such identification is required to assess migration from the can coating into the food and quantify dietary exposure. Polyester can coatings were extracted with acetonitrile at 40°C for 24h and the extracts were analyzed by a variety of analytical techniques, including GC-MS, HPLC-DAD/MS, HPLC-DAD/CAD and UHPL C-HRMS. Twenty nine non-volatile oligomers were tentatively identified using retention times, UV spectra, and accurate mass measurements. Identified oligomers suggest the coating in use for food cans is a polyester coating and is mainly based on the monomers isophthalic acid, terephthalic acid and nadic acid. To give confidence in the identification, one of the tentatively identified oligomer was synthetized and analyzed by (13)C and (1)H NMR and UHPL C-HRMS. The NMR and HRMS results, confirmed the presence of this compound in the can extracts. Finally, to determine if rapid, direct detection of the oligomers was practical, the coatings were analyzed by DART-HRMS. Twenty three out of the 29 oligomers were identified in the coating by direct measurement with DART-HRMS in few minutes.


Asunto(s)
Contaminación de Alimentos/análisis , Embalaje de Alimentos/normas , Poliésteres/química , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Cromatografía de Gases y Espectrometría de Masas
9.
J Agric Food Chem ; 64(11): 2377-85, 2016 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-26917426

RESUMEN

FDA guidance for food contact substances recommends that for food packaging intended for use at sterilized, high temperature processed, or retorted conditions, a migration test with a retort step at 121 °C for 2 h followed by a 10 day migration test at 40 °C should be performed. These conditions are in intended to simulate processing and long-term storage. However, can coatings may be in contact with food for years, and there are very few data evaluating if this short-term testing accurately simulates migration over extended time periods. A long-term migration test at 40 °C with retorted and non-retorted polyester cans using several food simulants (water, 3% acetic acid, 10% ethanol, 50% ethanol, and isooctane) was conducted to verify whether traditional migration testing protocols accurately predict migration from food contact materials used for extended time periods. Time points were from 1 day to 515 days. HPLC-MS/MS was used to analyze polyester monomers, and oligomer migration was monitored using HPLC-DAD/CAD and HPLC-MS. Concentrations of monomers and oligomers increased during the migration experiments, especially in ethanol food simulants. The data suggest that current FDA migration protocols may need to be modified to address changes in migrants as a result of long-term storage conditions.


Asunto(s)
Contaminación de Alimentos/análisis , Embalaje de Alimentos/instrumentación , Poliésteres/análisis , Cromatografía Líquida de Alta Presión/métodos , Conservación de Alimentos , Calor , Espectrometría de Masas en Tándem
10.
Artículo en Inglés | MEDLINE | ID: mdl-26744815

RESUMEN

A simple, rapid and sensitive method for analyzing multi-target and non-target additives in polyvinyl chloride (PVC) food can coatings using ultra-high-performance liquid chromatography coupled to quadrupole-orbital ion-trap mass spectrometry was developed. This procedure was used to study the behaviour of a cross-linking agent, benzoguanamine (BGA), two slip agents, oleamide and erucamide, and 18 other commonly used plasticisers including phthalates, adipates, sebacates, acetyl tributyl citrate and epoxidised soybean or linseed oils. This optimised method was used to detect these analytes in food simulants (water and 3% acetic acid) in a long-term migration test of PVC-coated food cans for a period ranging from 1 day to 1.5 years at 40°C. Although very low detection limits (5 ng ml(-1)) were obtained for the majority of compounds, none of the monitored plasticisers and slip agents was detected in simulants extracted from cans over the period of the test. However, the presence of BGA in both aqueous food simulants was confirmed based on high-resolution mass spectrometry, product ion spectra and analysis of a reference standard. The BGA concentration in both simulants continued to increase with storage time: after 1.5 years storage in aqueous food simulants at 40°C, BGA was detected at concentrations up to 84 µg dm(-2). We believe this is the first study describing the long-term migration capacity of BGA from any vinyl coating material intended for use in PVC-coated food cans. Our results may have implications for migration test protocols for food cans that will be stored for extended time periods.


Asunto(s)
Contaminación de Alimentos/análisis , Embalaje de Alimentos , Cloruro de Polivinilo/análisis , Acetatos/química , Cromatografía Líquida de Alta Presión , Reactivos de Enlaces Cruzados/química , Espectrometría de Masas , Estructura Molecular , Plastificantes/análisis , Factores de Tiempo , Agua/química
11.
Artículo en Inglés | MEDLINE | ID: mdl-25831019

RESUMEN

The potential for consumer exposure to nano-components in food contact materials (FCMs) is dependent on the migration of nanomaterials into food. Therefore, characterising the physico-chemical properties and potential for migration of constituents is an important step in assessing the safety of FCMs. A number of commercially available food storage products, purchased domestically within the United States and internationally, that claim to contain nanosilver were evaluated. The products were made of polyethylene, polypropylene and polyphenylene ether sulfone and all contained silver (0.001-36 mg kg(-1) of polymer). Silver migration was measured under various conditions, including using 3% acetic acid and water as food simulants. Low concentrations (sub-ppb levels) of silver were detected in the migration studies generally following a trend characterised by a surface desorption phenomenon, where the majority of the silver migration occurred in the first of three consecutive exposures. Silver nanoparticles were not detected in food simulants, suggesting that the silver migration may be due solely to ionic silver released into solution from oxidation of the silver nanoparticle surface. The absence of detectable silver nanoparticles was consistent with expectations from a physico-chemical view point. For the products tested, current USFDA guidance for evaluating migration from FCMs was applicable.


Asunto(s)
Contaminación de Alimentos/análisis , Embalaje de Alimentos , Nanopartículas del Metal/análisis , Plata/análisis , Ácido Acético/química , Agua/química
12.
Compr Rev Food Sci Food Saf ; 13(4): 679-692, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33412706

RESUMEN

This article is one of a series of 4 that report on a task of the NanoRelease Food Additive project of the Intl. Life Science Inst. Center for Risk Science Innovation and Application to identify, evaluate, and develop methods that are needed to confidently detect, characterize, and quantify intentionally produced engineered nanomaterials (ENMs) released from food along the alimentary tract. This particular article focuses on the problem of detecting ENMs that become released into food indirectly from food contact materials. In this review, an in-depth analysis of the release literature is presented and relevant release mechanisms are discussed. The literature review includes discussion of articles related to the release phenomenon in general, as experimental methods to detect ENMs migrating from plastic materials into other (nonfood) complex matrices were determined to be relevant to the focus problem of food safety. From the survey of the literature, several "control points" were identified where characterization data on ENMs and materials may be most valuable. The article concludes with a summary of findings and a discussion of potential knowledge gaps and targets for method development in this area.

13.
J Agric Food Chem ; 61(46): 11166-72, 2013 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-24144282

RESUMEN

This paper reports the validation and application of a method for determination of 10 perfluorochemicals (PFCs) in retail fish and shellfish. The analytes of interest were 7 perfluorinated carboxylates and 3 perfluorinated sulfonates. Fish and shellfish samples were digested with a basic solution of 10 mM sodium hydroxide in methanol before sonication and solid phase extraction through weak anion exchange. Analysis was performed using liquid chromatography-tandem mass spectrometry. Recoveries from spiking five different types of fish and shellfish indicate that the method performs similarly with different fish types, and recoveries were over 90% for all analytes. Forty-six retail samples, collected between 2010 and 2012, including 13 different types of fish and shellfish were analyzed for PFCs. The 13 different types included the top 10 most-consumed fish and shellfish in the United States according to data collected by the National Fisheries Institute. Two Standard Reference Materials were also analyzed. Most fish and shellfish had no detected PFCs; only 11 samples of the 46 tested had detectable concentrations of PFCs.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Fluorocarburos/química , Contaminación de Alimentos/análisis , Carne/análisis , Alimentos Marinos/análisis , Mariscos/análisis , Espectrometría de Masas en Tándem/métodos , Animales , Peces , Contaminantes Químicos del Agua/química
14.
J Agric Food Chem ; 60(7): 1652-8, 2012 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-22243628

RESUMEN

This study describes a new method developed for detection of 10 different perfluorochemicals (PFCs) in cow's milk, seven perfluorinated carboxylates and three perfluorinated sulfonate salts. After attempting multiple methods employing both acidic and basic extractions, a basic extraction using 10 mM sodium hydroxide in methanol digestion along with weak anion-exchange solid-phase extraction was employed. Vortex mixing and varying sonication times were compared as part of sample processing. Results show that sonication during sample processing yield decreased recovery of longer chain perfluorinated carboxylates. The final method developed was used to determine the concentration of PFCs in 12 raw and 49 retail milk samples from across the United States. With the exception of a single raw milk sample obtained from a dairy farm that had applied PFC containing biosolids to its fields, there were no milk samples containing PFCs.


Asunto(s)
Cromatografía Liquida/métodos , Fluorocarburos/análisis , Contaminación de Alimentos/análisis , Leche/química , Espectrometría de Masas en Tándem/métodos , Animales , Bovinos
15.
J Chromatogr A ; 1218(28): 4284-90, 2011 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-21641603

RESUMEN

This report presents the single-laboratory validation of a method for the determination of melamine in dairy-based products using on-line turbulent flow extraction-tandem mass spectrometry. Liquid or powder test portions were dissolved in water, enriched with (13)C(3)(15)N(3)-Melamine internal standard, followed by protein precipitation and withdrawal of an aliquot for analysis. The turbulent flow method was validated by analyses of liquid and powdered proficiency test portions containing up to 10mg/kg melamine. Accuracy of results ranged from 96 to 106% of the assigned values for the 6 proficiency test portions tested with relative standard deviations of 4-8%. Apparent recoveries based on addition of amino-(15)N(3)-Melamine to prepared test portions were between 98 and 114%. Based on the repeat analysis of a known blank sample the limit of detection and limit of quantification were determined to be 27 and 87 µg/kg, respectively. Additionally, this report demonstrates that turbulent flow chromatography is significantly faster than traditional LC-MS, with sample analysis times of less than 2 min.


Asunto(s)
Cromatografía Liquida/métodos , Cromatografía Liquida/normas , Fórmulas Infantiles/química , Espectrometría de Masas en Tándem/métodos , Espectrometría de Masas en Tándem/normas , Triazinas/análisis , Calibración , Humanos , Lactante , Modelos Lineales , Isótopos de Nitrógeno , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Triazinas/aislamiento & purificación
16.
J Agric Food Chem ; 59(13): 7178-85, 2011 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-21598963

RESUMEN

Metal food and drink cans are commonly coated with epoxy films made from phenolic polymers produced from bisphenol A (BPA). It is well established that residual BPA monomer migrates into can contents during processing and storage. While a number of studies have reported BPA concentrations in foods from foreign markets and specialty foods on the U.S. market, very few peer-reviewed data for the BPA concentrations in canned food from the U.S. market were available. This study quantified BPA concentrations in 78 canned and two frozen food products from the U.S. market using an adaptation of a previously reported liquid chromatography-tandem mass spectrometry method. The tested products represented 16 different food types that are from the can food classifications that constitute approximately 65% of U.S. canned food sales and canned food consumption. BPA was detected in 71 of the 78 canned food samples but was not detected in either of the two frozen food samples. Detectable BPA concentrations across all foods ranged from 2.6 to 730 ng/g. Large variations in BPA concentrations were found between different products of the same food type and between different lots of the same product. Given the large concentration ranges, the only distinguishable trend was that fruits and tuna showed the lowest BPA concentrations. Experiments with fortified frozen vegetables and brine solutions, as well as higher BPA concentrations in canned food solids over liquid portions, clearly indicated that BPA partitions into the solid portion of foods.


Asunto(s)
Contaminación de Alimentos/análisis , Alimentos en Conserva/análisis , Fenoles/análisis , Compuestos de Bencidrilo , Cromatografía Liquida , Embalaje de Alimentos , Metales , Espectrometría de Masas en Tándem , Estados Unidos
17.
Rapid Commun Mass Spectrom ; 25(9): 1336-42, 2011 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-21488128

RESUMEN

Two unknown compounds were previously determined to be potential interferences in liquid chromatography/tandem mass spectrometry (LC/MS/MS) analysis of bisphenol A (BPA) in canned infant formula. Both yielded two identical MS/MS transitions to BPA. The identities of the unknowns were investigated using accurate mass LC/MS, LC/MS/MS, and elemental formula and structures proposed. Exact identities were confirmed through purification or synthesis followed by (1)H and (13)C nuclear magnetic resonance (NMR) experiments, as well as comparisons of one unknown with commercial standards. Comparisons of negative ion electrospray ionization (ESI) MS/MS and accurate mass spectra suggested both unknowns to be structurally identical (to BPA and each other). Positive ion ESI spectra confirmed both were larger molecules, suggesting that in the negative mode they likely fragmented to the deprotonated BPA ion in the source [corrected]. Elemental composition of positive ion accurate mass spectra and NMR analysis concluded the unknowns were oxidized forms of the known epoxy can coating monomer, bisphenol A diglycidyl ether (BADGE). One of the unknowns, 2,2-[bis-4-(2,3-dihydroxypropoxy)phenyl]propane, commonly known as BADGE*2H(2)O, is widely reported as an epoxy-phenolic can coating migrant, but has not been suggested to interfere with the MS/MS analysis of BPA. The other unknown, 2-[4-(2,3-dihydroxypropoxy)phenyl]-2-[4'-hydroxyphenyl]propane, or the oxidized form of bisphenol A monoglycidyl ether (BAMGE*H(2)O), has not been previously reported in food or packaging.


Asunto(s)
Cromatografía Liquida/métodos , Embalaje de Alimentos , Fenoles/química , Propano/análogos & derivados , Propano/química , Espectrometría de Masas en Tándem/métodos , Compuestos de Bencidrilo , Fórmulas Infantiles/química , Resonancia Magnética Nuclear Biomolecular , Fenoles/análisis , Propano/análisis
19.
J Agric Food Chem ; 58(4): 2307-13, 2010 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-20102208

RESUMEN

An updated survey of U.S. infant formula was conducted to determine the concentrations of bisphenol A (BPA). The purpose was to accurately assess BPA concentrations across the infant formula market, accounting for lot variability, and determine if geographic location or can age influences BPA concentrations. A method was developed to measure BPA in formula utilizing isotope dilution, solid-phase extraction, and liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The method was tested and found to be reproducible (10% relative standard deviation), reliable (47 +/- 1% recovery), and sensitive (0.15 ng g(-1) method detection limit). Over 160 analyses were conducted using 104 formula containers representing 36 products. Samples from U.S. east and west coast markets demonstrated no significant difference, and concentrations in older cans were not higher. BPA concentrations in liquid formula (0.48-11 ng g(-1)) were consistent with previous studies, and BPA was detected in only 1 of 14 powder formula products analyzed.


Asunto(s)
Fórmulas Infantiles/química , Fenoles/análisis , Animales , Compuestos de Bencidrilo , Canadá , Bovinos , Cromatografía Líquida de Alta Presión/métodos , Alimentos Fortificados/análisis , Alimentos en Conserva/análisis , Humanos , Lactante , Espectrometría de Masas , Leche/química , Leche de Soja/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Estados Unidos
20.
J AOAC Int ; 91(3): 511-23, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18567295

RESUMEN

The accuracy, repeatability, and reproducibility characteristics of a method using multitoxin immunoaffinity column cleanup with liquid chromatography (LC) for determination of aflatoxins (AF; sum of aflatoxins B1, B2, G1, and G2) and ochratoxin A (OTA) in powdered ginseng and ginger have been established in a collaborative study involving 13 laboratories from 7 countries. Blind duplicate samples of blank, spiked (AF and OTA added) at levels ranging from 0.25 to 16.0 microg/kg for AF and 0.25 to 8.0 microg/kg for OTA were analyzed. A naturally contaminated powdered ginger sample was also included. Test samples were extracted with methanol and 0.5% aqueous sodium hydrogen carbonate solution (700 + 300, v/v). The extract was centrifuged, diluted with phosphate buffer (PB), filtered, and applied to an immunoaffinity column containing antibodies specific for AF and OTA. After washing the column with water, the toxins were eluted from the column with methanol, and quantified by high-performance LC with fluorescence detection. Average recoveries of AF from ginseng and ginger ranged from 70 to 87% (at spiking levels ranging from 2 to 16 microg/kg), and of OTA, from 86 to 113% (at spiking levels ranging from 1 to 8 microg/kg). Relative standard deviations for within-laboratory repeatability (RSDr) ranged from 2.6 to 8.3% for AF, and from 2.5 to 10.7% for OTA. Relative standard deviations for between-laboratory reproducibility (RSDR) ranged from 5.7 to 28.6% for AF, and from 5.5 to 10.7% for OTA. HorRat values were < or = 2 for the multi-analytes in the 2 matrixes.


Asunto(s)
Aflatoxinas/análisis , Cromatografía de Afinidad/métodos , Cromatografía Liquida/métodos , Ocratoxinas/análisis , Panax/química , Zingiber officinale/química , Aflatoxina B1/análisis , Aflatoxinas/normas , Cromatografía de Afinidad/normas , Cromatografía Liquida/normas , Conducta Cooperativa , Indicadores y Reactivos , Ocratoxinas/normas , Estándares de Referencia
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