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1.
Artigo em Inglês | MEDLINE | ID: mdl-38170576

RESUMO

A call for data on the occurrence of alkylfurans in food and feed from EFSA triggered the development of new methods to cover next to furan also 2- and 3-methylfuran, 2,5-dimethyl- and 2-ethylfuran as well as 2-pentylfuran. A significant variability was noticed when comparing analysis of 2-pentylfuran and furans in the same matrix performed by different laboratories. To assess the variability an interlaboratory study including eight laboratories was organised. The highest variabilities were observed when analysing cereals, with measurements of 2-pentylfuran indicating concentrations from 8 mg/kg up to more than 1000 mg/kg in the same sample. This study illustrates that the analysis of 2-pentylfuran requires special attention, and that additional method development would be necessary to ensure reliable and reproducible determination of 2-pentylfuran at contamination level. Moreover, a recent evaluation of the EFSA Panel on Food Additives and Flavourings indicates that concerns for genotoxicity, reason why it was grouped with the shorter alkylfurans, are now ruled out. We question the need and justification to include 2-pentylfuran in the analytical method as requested by EFSA, from both the analytical and the safety perspective.


Assuntos
Grão Comestível , Furanos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Furanos/análise , Grão Comestível/química
2.
Artigo em Inglês | MEDLINE | ID: mdl-34418759

RESUMO

Alkylfurans have been found concurrently to furan in thermally processed food and might add to the overall exposure, thereby increase the health concern. The analytical methods developed for these compounds are based on gas chromatography separation coupled to mass spectrometry. Two of those alkylfurans, 2,5-dimethylfuran and 2-ethylfuran, are isomers, for which accurate quantification require either complete chromatographic separation or tandem mass spectrometry (MS/MS) selectivity. A new chromatographic method is reported using the Supelco Equity-1 column, demonstrating complete baseline separation of these two isomers, with a shorter runtime when using single mass spectrometry. Full validation was performed successfully for furan, 2- and 3-methylfuran, 2-ethylfuran, 2,5-dimethylfuran and 2-pentylfuran on different food matrices with recovery rates in the range of 80-110 %, repeatability below 14%, intermediate reproducibility below 22% as well as expanded uncertainty under 50%.


Assuntos
Café/química , Grão Comestível/química , Furanos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Furanos/química , Furanos/isolamento & purificação , Humanos , Lactente , Alimentos Infantis/análise , Modelos Lineares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Microextração em Fase Sólida/métodos
3.
J Prof Nurs ; 36(6): 514-519, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33308549

RESUMO

Although nurse educators may prefer to avert student failure, they need to handle the situation competently when failure occurs. Thus, faculty should know how to inform the student and administration of course failure, process their own emotions, and learn from the experience. However, many nurse educators lack confidence in dealing with the consequences of assigning a failing grade. This manuscript aims to provide foundational knowledge on managing student failure after it happens. Planning the timing, setting, and conversation can ease this challenging process. Despite faculty attempts to present the information compassionately, students may react aggressively. Consequently, faculty should develop a strategy to maintain safety. In addition, faculty may find it daunting to notify administrators of a student's failure, but preparing objective data based on missed course outcomes can promote administrator support of the decision. This factual rationale for the course failure also assists the faculty during a potential student appeal. Following the initial conversations with the student and administration, faculty should plan a time of respite to recover from the conflicting emotions that typically results from assigning a failing grade. Additionally, individual reflection and discussion with a mentor will help the educator to process the experience and grow professionally.


Assuntos
Fracasso Acadêmico , Educação em Enfermagem , Estudantes de Enfermagem , Docentes de Enfermagem , Humanos , Mentores
4.
J Agric Food Chem ; 68(29): 7727-7733, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32578985

RESUMO

The study reports the role of choline and compounds thereof in the formation of chlormequat under thermal conditions, with emphasis on the molecular mechanism involved in the transformation. The data show the decomposition of choline to chlormequat at 200 °C in presence of chloride ions, likely by nucleophilic substitution. Furthermore, the results suggest that phosphatidylcholine, glycerophosphocholine, and phosphocholine are the effective precursors of chlormequat under sufficient thermal conditions due to their capability to degrade to choline and/or the ability of the phosphate moiety to behave as a good leaving group with respect to nucleophilic attacks. Thermal treatments (120 and 200 °C) applied to egg powder, rich in phosphatidylcholine, and wheat flour, with choline at a substantial level, suggest that less energy is required for obtaining chlormequat from phosphatidylcholine than from choline. This observation is consistent with the postulated mechanism of a nucleophilic substitution with phosphate moieties acting as better leaving groups than the hydroxyl group.


Assuntos
Clormequat/análise , Ovos/análise , Farinha/análise , Reguladores de Crescimento de Plantas/análise , Triticum/química , Animais , Galinhas , Colina/análise , Temperatura Alta
5.
J Chromatogr A ; 1622: 461119, 2020 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-32376013

RESUMO

Next to furan, other alkylfurans such as 2- and 3-methylfuran, 2-ethylfuran, 2,5-dimethylfuran, and 2-pentylfuran have been found concurrently in thermal processed food and fruit juices. To ensure an accurate quantification of these compounds, a method based on isotope dilution using all six respective internal standards and gas chromatography coupled to mass spectrometry was developed. Two injection techniques, static head space (HS) and solid phase micro extraction (SPME), were tested and compared for their performance. Validation was based on a single laboratory validation under repeatability condition. Good data for both techniques in baby food and cereals were obtained. Furthermore, validation was conducted successfully on fruit juices and infant formula using SPME injection and on coffee using HS injection. LOQ for all matrices was established at 5 µg/kg and 200 µg/kg in coffee samples, which corresponds to the lowest fortification level. Recovery was between 80 % and 110 % and repeatability obtained below 16 % at 50 µg/kg (7.4 % at 10 mg/kg for coffee samples), except few slight outliers.


Assuntos
Análise de Alimentos/métodos , Furanos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Café/química , Grão Comestível/química , Sucos de Frutas e Vegetais/análise , Humanos , Lactente , Alimentos Infantis/análise , Microextração em Fase Sólida
6.
J Am Vet Med Assoc ; 253(3): 322-336, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30020006

RESUMO

OBJECTIVE To estimate Brucella canis seropositivity rates for purebred dogs being bred by noncommercial breeders, describe epidemiological findings in infected commercial dog-production facilities, and characterize B canis infection in pet dogs and the risk to human health. DESIGN Retrospective descriptive study. SAMPLE 2,799 canine specimens submitted to the Michigan State University Veterinary Diagnostic Laboratory for B canis testing and records of B canis reports provided to the Michigan Department of Agriculture and Rural Development from 2007 through 2016. PROCEDURES Results of B canis laboratory tests and epidemiological findings for reported cases of B canis were reviewed and summarized. Federal and state public health officials were interviewed regarding human B canis infection. State veterinarians were interviewed regarding canine brucellosis reporting and control procedures. RESULTS Estimated B canis seropositivity was 0.4% among purebred Michigan dogs owned by noncommercial breeders. Infection was confirmed in dogs from 17 commercial dog-production facilities, 3 shelters, and 1 rescue agency. Estimated infection prevalence in production facilities ranged from 2 of 22 (9%) to 5 of 6 (83%). Transfer of infected dogs involved 22 Michigan counties and 11 states. Seven of 20 privately owned infected dogs had diskospondylitis; I also had uveitis. Fifty-three veterinary hospital or diagnostic laboratory personnel had inadvertent exposure to the pathogen. Brucella canis was isolated from 1 commercial production facility owner. CONCLUSIONS AND CLINICAL RELEVANCE B canis was uncommon in purebred dogs being bred by noncommercial breeders but endemic in Michigan commercial facilities producing dogs destined to become household pets. Infected pet dogs caused human B canis exposure, and several pet dogs had debilitating disease not associated with the reproductive system.


Assuntos
Criação de Animais Domésticos , Brucella canis/isolamento & purificação , Brucelose/veterinária , Surtos de Doenças/veterinária , Doenças do Cão/epidemiologia , Animais , Cruzamento , Brucelose/epidemiologia , Demografia , Doenças do Cão/transmissão , Cães , Feminino , Humanos , Masculino , Michigan/epidemiologia , Animais de Estimação , Prevalência , Zoonoses/epidemiologia
7.
J Am Vet Med Assoc ; 251(8): 912-921, 2017 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-28959928

RESUMO

OBJECTIVE To measure blood lead concentrations (BLCs) in dogs living in Flint, Mich, following a declared water crisis and to assess potential associations of BLCs with demographic data, water sources, and clinical signs in these dogs. DESIGN Cross-sectional study. ANIMALS 284 dogs residing in Flint, Mich (test population), and 47 dogs residing in East Lansing, Mich (control population), and immediately adjacent areas. PROCEDURES Blood samples were collected at free screening clinics in Flint (test population) and at the Michigan State University College of Veterinary Medicine Veterinary Medical Center (control population). Owners of test population dogs completed questionnaires providing demographic and clinical information. Hematologic evaluations were performed; BLCs were measured by inductively coupled plasma-mass spectrometry. RESULTS 4 of 284 test population dogs had BLCs > 50 ppb; an additional 20 had BLCs > 20 ppb. Overall, BLCs of test population dogs were higher than those of control dogs. Within the test population, young dogs (≤ 2 years of age) had higher BLCs than old dogs (≥ 6 years of age). Only 7.2% of test population dogs were drinking unfiltered tap water at the time of screening; however, dogs that had been receiving filtered or bottled water for ≤ 3 months before screening had higher BLCs than did those that received such water for > 3 months. CONCLUSIONS AND CLINICAL RELEVANCE Taken together, findings suggested that the impact of the Flint water crisis extended to companion animals. Results highlighted the importance of maintaining awareness of lead exposure and considering both human and animal well-being in cases of environmental toxicant exposures.


Assuntos
Doenças do Cão/sangue , Água Potável/química , Intoxicação por Chumbo/veterinária , Chumbo/sangue , Animais , Estudos Transversais , Doenças do Cão/diagnóstico , Doenças do Cão/epidemiologia , Cães , Feminino , Intoxicação por Chumbo/sangue , Intoxicação por Chumbo/diagnóstico , Intoxicação por Chumbo/epidemiologia , Masculino , Michigan/epidemiologia
8.
Artigo em Inglês | MEDLINE | ID: mdl-28869741

RESUMO

The increasing number of food frauds using exogenous nitrogen-rich adulterants to artificially raise the protein content for economically motivated adulteration has demonstrated the need for a robust analytical methodology. This method should be applicable for quality control in operations covering a wide range of analyte concentrations to be able to analyse high levels as usually found in adulteration, as well as low levels due to contamination. The paper describes a LC-MS/MS method covering 14 nitrogen-rich adulterants using a simple and fast sample preparation based on dilution and clean-up by dispersive SPE. Quantification is carried out by isotopic dilution reaching LOQs of 0.05-0.20 mg/kg in a broad range of food matrices (infant formula, liquid milk, dairy ingredient, high protein meal, cereal, infant cereal, and meat/fish powder). Validation of seven commodity groups was performed according to SANCO 12571/2013, giving satisfactory results demonstrating the method's fitness for purpose at the validated range at contamination level. Method ruggedness was further assessed by transferring the developed method into another laboratory devoted to routine testing for quality control. Next to the method description, emphasis is placed on challenges and problems appearing during method development as well as validation. They are discussed in detail and solutions are provided.


Assuntos
Aditivos Alimentares/análise , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Nitrogênio/análise , Cromatografia Líquida , Estrutura Molecular , Espectrometria de Massas em Tandem
9.
Artigo em Inglês | MEDLINE | ID: mdl-28730944

RESUMO

Food contact materials (FCM) contain chemicals which can migrate into food and result in human exposure. Although it is mandatory to ensure that migration does not endanger human health, there is still no consensus on how to pragmatically assess the safety of FCM since traditional approaches would require extensive toxicological and analytical testing which are expensive and time consuming. Recently, the combination of bioassays, analytical chemistry and risk assessment has been promoted as a new paradigm to identify toxicologically relevant molecules and address safety issues. However, there has been debate on the actual value of bioassays in that framework. In the present work, a FCM anticipated to release the endocrine active chemical 4-nonyphenol (4NP) was used as a model. In a migration study, the leaching of 4NP was confirmed by LC-MS/MS and GC-MS. This was correlated with an increase in both estrogenic and anti-androgenic activities as measured with bioassays. A standard risk assessment indicated that according to the food intake scenario applied, the level of 4NP measured was lower, close or slightly above the acceptable daily intake. Altogether these results show that bioassays could reveal the presence of an endocrine active chemical in a real-case FCM migration study. The levels reported were relevant for safety assessment. In addition, this work also highlighted that bioactivity measured in migrate does not necessarily represent a safety issue. In conclusion, together with analytics, bioassays contribute to identify toxicologically relevant molecules leaching from FCM and enable improved safety assessment.


Assuntos
Bioensaio/métodos , Disruptores Endócrinos/análise , Contaminação de Alimentos/análise , Embalagem de Alimentos/instrumentação , Embalagem de Alimentos/métodos , Humanos , Espectrometria de Massas em Tandem/métodos
10.
Chimia (Aarau) ; 70(5): 329-33, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27198809

RESUMO

Crises related to the presence of melamine in milk or horse meat in beef have been a wake-up call to the whole food industry showing that adulteration of food raw materials is a complex issue. By analysing the situation, it became clear that the risk-based approach applied to ensure the safety related to chemical contaminants in food is not adequate for food fraud. Therefore, a specific approach has been developed to evaluate adulteration vulnerabilities within the food chain. Vulnerabilities will require the development of new analytical solutions. Fingerprinting methodologies can be very powerful in determining the status of a raw material without knowing the identity of each constituent. Milk adulterated by addition of adulterants with very different chemical properties could be detected rapidly by Fourier-transformed mid-infrared spectroscopy (FT-mid-IR) fingerprinting technology. In parallel, a fast and simple multi-analytes liquid-chromatography tandem mass-spectrometry (LC/MS-MS) method has been developed to detect either high levels of nitrogen-rich compounds resulting from adulteration or low levels due to accidental contamination either in milk or in other sensitive food matrices. To verify meat species authenticity, DNA-based methods are preferred for both raw ingredients and processed food. DNA macro-array, and more specifically the Meat LCD Array have showed efficient and reliable meat identification, allowing the simultaneous detection of 32 meat species. While the Meat LCD Array is still a targeted approach, DNA sequencing is a significant step towards an untargeted one.

12.
Artigo em Inglês | MEDLINE | ID: mdl-24552621

RESUMO

Tris(nonylphenyl)phosphite, an antioxidant used in polyethylene resins for food applications, is problematic since it is a source of the endocrine-disrupting chemicals 4-nonylphenols (4NP) upon migration into packaged foods. As a response to concerns surrounding the presence of 4NP-based compounds in packaging materials, some resin producers and additive suppliers have decided to eliminate TNPP from formulations. This paper describes an analytical procedure to verify the "TNPP-free" statement in multilayer laminates used for bag-in-box packaging. The method involves extraction of TNPP from laminates with organic solvents followed by detection/quantification by LC-MS/MS using the atmospheric pressure chemical ionisation (APCI) mode. A further acidic treatment of the latter extract allows the release of 4NP from potentially extracted TNPP. 4NP is then analysed by LC-MS/MS using electrospray ionisation (ESI) mode. This two-step analytical procedure ensures not only TNPP quantification in laminates, but also allows the flagging of other possible sources of 4NP in such packaging materials, typically as non-intentionally added substances (NIAS). The limits of quantification were 0.50 and 0.48 µg dm⁻² for TNPP and 4NP in laminates, respectively, with recoveries ranging between 87% and 114%. Usage of such analytical methodologies in quality control operations has pointed to a lack of traceability at the packaging supplier level and cross-contamination of extrusion equipment at the converter level, when TNPP-containing laminates are processed on the same machine beforehand.


Assuntos
Antioxidantes/análise , Qualidade de Produtos para o Consumidor , Disruptores Endócrinos/análise , Embalagem de Alimentos , Organofosfonatos/análise , Fenóis/análise , Fosfitos/análise , Alumínio/química , Antioxidantes/química , Ásia , Cromatografia Líquida de Alta Pressão , Disruptores Endócrinos/química , Europa (Continente) , Contaminação de Alimentos/prevenção & controle , Rotulagem de Alimentos , Fidelidade a Diretrizes , Limite de Detecção , Organofosfonatos/química , Fenóis/química , Fosfitos/química , Polietileno/química , Polietilenotereftalatos/química , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray , Suíça , Espectrometria de Massas em Tandem
13.
J Agric Food Chem ; 58(6): 3700-7, 2010 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-20180576

RESUMO

The present paper describes the development of an analytical method for the semiquantitative analysis of 3-butenyl isothiocyanate in mustard seeds, this compound being linked to an undesirable (at least for the European palate) off-flavor. 3-Butenyl isothiocyanate is one of the enzymatic degradation products of gluconapin, a member of the glucosinolate family of compounds. A headspace-gas chromatography-mass spectrometry (HS-GC-MS) method has been developed for the rapid analysis of 3-butenyl isothiocyanate in mustard seeds. The cross-check of this HS-GC-MS method has been made on the basis of the analysis of the native gluconapin using liquid chromatography coupled to time-of-flight mass spectrometry (LC-TOF-MS). Both techniques gave comparable results. The HS-GC-MS method was kept as the method of choice as it is rapid and solvent-free. Because yellow mustard seeds do not normally contain gluconapin, its presence in such seeds above the limit of detection was already considered as a criterion for potentially problematic mustard batches. However, "organoleptically" acceptable brown mustard seeds already contained measurable amounts of gluconapin and had to be differentiated from mustard seeds containing nonacceptable levels of gluconapin, as it is typically the case for brown mustard originating from the Indian subcontinent. Thus, a 3-butenyl isothiocyanate content "cut point" has been established to discriminate between batches. This limit could then be applied for the acceptance or rejection of mustard seed batches. In addition, LC-TOF-MS screening of mustard seeds from different geographic origins showed the heterogeneity of the glucosinolate profile and the difficulty to find good origin markers.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Glucosinolatos/análise , Isotiocianatos/análise , Mostardeira/química , Controle de Qualidade , Sementes/química
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