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1.
EFSA J ; 16(3): e05082, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32625822

RESUMO

Moniliformin (MON) is a mycotoxin with low molecular weight primarily produced by Fusarium fungi and occurring predominantly in cereal grains. Following a request of the European Commission, the CONTAM Panel assessed the risk of MON to human and animal health related to its presence in food and feed. The limited information available on toxicity and on toxicokinetics in experimental and farm animals indicated haematotoxicity and cardiotoxicity as major adverse health effects of MON. MON causes chromosome aberrations in vitro but no in vivo genotoxicity data and no carcinogenicity data were identified. Due to the limitations in the available toxicity data, human acute or chronic health-based guidance values (HBGV) could not be established. The margin of exposure (MOE) between the no-observed-adverse-effect level (NOAEL) of 6.0 mg/kg body weight (bw) for cardiotoxicity from a subacute study in rats and the acute upper bound (UB) dietary exposure estimates ranged between 4,000 and 73,000. The MOE between the lowest benchmark dose lower confidence limit (for a 5% response - BMDL05) of 0.20 mg MON/kg bw per day for haematological hazards from a 28-day study in pigs and the chronic dietary human exposure estimates ranged between 370 and 5,000,000 for chronic dietary exposures. These MOEs indicate a low risk for human health but were associated with high uncertainty. The toxicity data available for poultry, pigs, and mink indicated a low or even negligible risk for these animals from exposure to MON in feed at the estimated exposure levels under current feeding practices. Assuming similar or lower sensitivity as for pigs, the CONTAM Panel considered a low or even negligible risk for the other animal species for which no toxicity data suitable for hazard characterisation were identified. Additional toxicity studies are needed and depending on their outcome, the collection of more occurrence data on MON in food and feed is recommended to enable a comprehensive human risk assessment.

2.
EFSA J ; 16(8): e05367, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32626015

RESUMO

4,15-Diacetoxyscirpenol (DAS) is a mycotoxin primarily produced by Fusarium fungi and occurring predominantly in cereal grains. As requested by the European Commission, the EFSA Panel on Contaminants in the Food Chain (CONTAM) assessed the risk of DAS to human and animal health related to its presence in food and feed. Very limited information was available on toxicity and on toxicokinetics in experimental and farm animals. Due to the limitations in the available data set, human acute and chronic health-based guidance values (HBGV) were established based on data obtained in clinical trials of DAS as an anticancer agent (anguidine) after intravenous administration to cancer patients. The CONTAM Panel considered these data as informative for the hazard characterisation of DAS after oral exposure. The main adverse effects after acute and repeated exposure were emesis, with a no-observed-adverse-effect level (NOAEL) of 32 µg DAS/kg body weight (bw), and haematotoxicity, with a NOAEL of 65 µg DAS/kg bw, respectively. An acute reference dose (ARfD) of 3.2 µg DAS/kg bw and a tolerable daily intake (TDI) of 0.65 µg DAS/kg bw were established. Based on over 15,000 occurrence data, the highest acute and chronic dietary exposures were estimated to be 0.8 and 0.49 µg DAS/kg bw per day, respectively, and were not of health concern for humans. The limited information for poultry, pigs and dogs indicated a low risk for these animals at the estimated DAS exposure levels under current feeding practices, with the possible exception of fattening chicken. Assuming similar or lower sensitivity than for poultry, the risk was considered overall low for other farm and companion animal species for which no toxicity data were available. In consideration of the similarities of several trichothecenes and the likelihood of co-exposure via food and feed, it could be appropriate to perform a cumulative risk assessment for this group of substances.

3.
EFSA J ; 15(9): e04718, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32625635

RESUMO

Deoxynivalenol (DON) is a mycotoxin primarily produced by Fusarium fungi, occurring predominantly in cereal grains. Following the request of the European Commission, the CONTAM Panel assessed the risk to animal and human health related to DON, 3-acetyl-DON (3-Ac-DON), 15-acetyl-DON (15-Ac-DON) and DON-3-glucoside in food and feed. A total of 27,537, 13,892, 7,270 and 2,266 analytical data for DON, 3-Ac-DON, 15-Ac-DON and DON-3-glucoside, respectively, in food, feed and unprocessed grains collected from 2007 to 2014 were used. For human exposure, grains and grain-based products were main sources, whereas in farm and companion animals, cereal grains, cereal by-products and forage maize contributed most. DON is rapidly absorbed, distributed, and excreted. Since 3-Ac-DON and 15-Ac-DON are largely deacetylated and DON-3-glucoside cleaved in the intestines the same toxic effects as DON can be expected. The TDI of 1 µg/kg bw per day, that was established for DON based on reduced body weight gain in mice, was therefore used as a group-TDI for the sum of DON, 3-Ac-DON, 15-Ac-DON and DON-3-glucoside. In order to assess acute human health risk, epidemiological data from mycotoxicoses were assessed and a group-ARfD of 8 µg/kg bw per eating occasion was calculated. Estimates of acute dietary exposures were below this dose and did not raise a health concern in humans. The estimated mean chronic dietary exposure was above the group-TDI in infants, toddlers and other children, and at high exposure also in adolescents and adults, indicating a potential health concern. Based on estimated mean dietary concentrations in ruminants, poultry, rabbits, dogs and cats, most farmed fish species and horses, adverse effects are not expected. At the high dietary concentrations, there is a potential risk for chronic adverse effects in pigs and fish and for acute adverse effects in cats and farmed mink.

4.
Artigo em Inglês | MEDLINE | ID: mdl-24823431

RESUMO

Tropane alkaloids (TAs) are toxic secondary metabolites produced by plants of, inter alia, the genera Datura (thorn apple) and Atropa (deadly nightshade). The most relevant TAs are (-)-L-hyoscyamine and (-)-L-scopolamine, which act as antagonists of acetylcholine muscarinic receptors and can induce a variety of distinct toxic syndromes in mammals (anti-cholinergic poisoning). The European Union has regulated the presence of seeds of Datura sp. in animal feeds, specifying that the content should not exceed 1000 mg kg(-1) (Directive 2002/32/EC). For materials that have not been ground, visual screening methods are often used to comply with these regulations, but these cannot be used for ground materials and compound feeds. Immunological assays, preferably in dipstick format, can be a simple and cost-effective approach to monitor feedstuffs in an HACCP setting in control laboratories. So far no reports have been published on immunoassays that are capable of detecting both hyoscyamine and scopolamine with equal sensitivity and that can be used, preferably in dipstick format, for application as a fast screening tool in feed analysis. This study presents the results obtained for the in-house and inter-laboratory validation of a dipstick immunoassay for the detection of hyoscyamine and scopolamine in animal feed. The target level was set at 800 µg kg(-1) for the sum of both alkaloids. By using a representative set of compound feeds during validation and a robust study design, a reliable impression of the relevant characteristics of the assay could be obtained. The dipstick test displayed similar sensitivity towards the two alkaloids and it could be concluded that the test has a very low probability of producing a false-positive result at blank level or a false-negative result at target level. The assay can be used for monitoring of TAs in feedstuffs, but has also potential as a quick screening tool in food- or feed-related poisonings.


Assuntos
Ração Animal/análise , Contaminação de Alimentos/análise , Hiosciamina/análise , Imunoensaio/métodos , Escopolamina/análise , Ração Animal/toxicidade , Animais , Atropa/química , Atropa/intoxicação , Bovinos , Datura stramonium/química , Datura stramonium/intoxicação , União Europeia , Reações Falso-Negativas , Reações Falso-Positivas , Contaminação de Alimentos/legislação & jurisprudência , Hiosciamina/intoxicação , Imunoensaio/normas , Escopolamina/intoxicação , Sementes/química , Sementes/intoxicação
5.
Anal Bioanal Chem ; 406(3): 757-70, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24327075

RESUMO

Pyrrolizidine alkaloids (PAs) are a group of plant secondary metabolites with carcinogenic and hepatotoxic properties. When PA-producing plants contaminate crops, toxins can be transferred through the food chain and cause illness in humans and animals, most notably hepatic veno-occlusive disease. Honey has been identified as a direct risk of human exposure. The European Food Safety Authority has recently identified four groups of PAs that are of particular importance for food and feed: senecionine-type, lycopsamine-type, heliotrine-type and monocrotaline-type. Liquid or gas chromatography methods are currently used to detect PAs but there are no rapid screening assays available commercially. Therefore, the aim of this study was to develop a rapid multiplex ELISA test for the representatives of three groups of alkaloids (senecionine, lycopsamine and heliotrine types) that would be used as a risk-management tool for the screening of these toxic compounds in food and feed. The method was validated for honey and feed matrices and was demonstrated to have a detection capability less than 25 µg/kg for jacobine, lycopsamine, heliotrine and senecionine. The zinc reduction step introduced to the extraction procedure allows for the additional detection of the presence of N-oxides of PAs. This first multiplex immunoassay for PA detection with N-oxide reduction can be used for the simultaneous screening of 21 samples for >12 PA analytes. Honey samples (n = 146) from various origins were analysed for PA determination. Six samples were determined to contain measurable PAs >25 µg/kg by ELISA which correlated to >10 µg/kg by LC-MS/MS.


Assuntos
Ensaio de Imunoadsorção Enzimática , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Mel/análise , Óxidos/análise , Alcaloides de Pirrolizidina/análise , Ração Animal/análise , Limite de Detecção , Óxidos/química , Fatores de Tempo
6.
Artigo em Inglês | MEDLINE | ID: mdl-23895245

RESUMO

Phomopsins (PHO) are mycotoxins produced by the fungus Diaporthe toxica (also referred to as Phomopsis leptostromiformis). Lupin is the most important host crop for this fungus and PHO are suspected as cause of lupinosis, a deadly liver disease, in sheep. Lupin is currently in use to replace genetically modified soy in many food products available on the European market. However, a validated method for analysis of PHO is not available until now. In this work, a dilute-and-shoot LC-MS/MS-based method was developed for the quantitative determination and identification of phomopsin A (PHO-A) in lupin and lupin-containing food. The method involved extraction by a mixture of acetonitrile/water/acetic acid (80/20/1 v/v), dilution of the sample in water, and direct injection of the crude extract after centrifugation. The method was validated at 5 and 25 µg PHO-A kg(-1) product. The average recovery and RSD obtained were 79% and 9%, respectively. The LOQ (the lowest level for which adequate recovery and RSD were demonstrated) was 5 µg PHO-A kg(-1). Identification of PHO-A was based on retention time and two transitions (789 > 226 and 789 > 323). Using the average of solvent standards from the sequence as a reference, retention times were all within ± 0.03 min and ion ratios were within ± 12%, which is compliant with European Union requirements. The LOD (S/N = 3 for the least sensitive transition) was 1 µg PHO-A kg(-1) product. Forty-two samples of lupin and lupin-containing food products were collected in 2011-2012 from grocery stores and internet shops in the Netherlands and analysed. In none of the samples was PHO-A detected.


Assuntos
Contaminação de Alimentos/análise , Lupinus/química , Micotoxinas/análise , Animais , Cromatografia Líquida/métodos , Humanos , Limite de Detecção , Lupinus/efeitos adversos , Micotoxinas/efeitos adversos , Países Baixos , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos
8.
J AOAC Int ; 94(3): 900-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21797019

RESUMO

A liquid chromatographic method for the determination of fumonisins B1 (FB1) and B2 (FB2) in corn-based foods for infants and young children was subjected to an interlaboratory validation study involving 11 laboratories. Five blind duplicate sample pairs of each matrix were analyzed to establish the accuracy, repeatability, and reproducibility of the method. Mass fractions in the baby food samples ranged from 89.1 to 384.4 microg/kg FB1 and from 22.5 to 73.6 microg/kg FB2. The method involved a warm extraction with citrate phosphate buffer-methanol-acetonitrile (50 + 25 + 25, v/v/v), a cleanup through an immunoaffinity column, and an end-determination of fumonisins by LC after automated precolumn derivatization with o-phthaldialdehyde reagent. RSDs for within-laboratory repeatability (RSDr) ranged from 6.8 to 23.5% for FB1 and 7.6 to 22.9% for FB2. RSDs for between-laboratory reproducibility (RSDR) ranged from 15.4 to 26.2% for FB1 and 21.6 to 36.3% for FB2. Mean FB1 recoveries from baby foods spiked at 100.0 and 250.0 microg/kg were 89 and 96%, respectively; for FB2 spiked foods at 25.0 and 62.5 microg/kg recoveries were 90 and 85%, respectively. HorRat values ranged from 0.8 to 1.2 for FB1, whereas for FB2 they ranged from 0.9 to 1.4 when calculated according to Horwitz, and from 1.0 to 1.7 when calculated according to Thompson, indicating an acceptable among-laboratory precision for all matrixes (HorRat values <2).


Assuntos
Cromatografia Líquida/métodos , Cromatografia/métodos , Fumonisinas/química , Alimentos Infantis/análise , Zea mays/química , Calibragem , Pré-Escolar , Análise de Alimentos/métodos , Contaminação de Alimentos , Humanos , Lactente , Laboratórios/normas , Reprodutibilidade dos Testes
9.
Anal Chem ; 83(11): 4206-13, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21495670

RESUMO

A surface plasmon resonance (SPR) optical biosensor method was developed for the detection of paralytic shellfish poisoning (PSP) toxins in shellfish. This application was transferred in the form of a prototype kit to seven laboratories using Biacore Q SPR optical biosensor instrumentation for interlaboratory evaluation. Each laboratory received 20 shellfish samples across a range of species including blind duplicates for analysis. The samples consisted of 4 noncontaminated samples spiked in duplicate with a low level of PSP toxins (240 µg STXdiHCl equivalents/kg), a high level of saxitoxin (825 µg STXdiHCl/kg), 2 noncontaminated, and 14 naturally contaminated samples. All 7 participating laboratories completed the study, and HorRat values obtained were <1 demonstrating that the method performance was acceptable. Mean recoveries expressed as STXdiHCl equivalents/kg were 94.6 ± 16.8% for the low level PSP toxin mix and 98.6 ± 5.6% for the high level of saxitoxin. Relative standard deviations for within-laboratory variations (RSD(r): repeatability) and between-laboratory variations (RSD(R) = reproducibility) ranged from 1.8 to 9.6% and 2.9 to 18.3% respectively. This first ever reported SPR biosensor interlaboratory study demonstrated this PSP application to be an empowering tool in the drive toward the reduction and replacement of the mouse bioassay within Europe.


Assuntos
Toxinas Marinhas/análise , Frutos do Mar/análise , Ressonância de Plasmônio de Superfície/métodos , Técnicas Biossensoriais/métodos , Laboratórios , Projetos Piloto , Saxitoxina/análise
10.
J Toxicol ; 2010: 313280, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20652038

RESUMO

Pyrrolizidine alakloids (PAs) are known to cause hepatic veno-occlusive disease (VOD). Outbreaks have occurred in Western Afghanistan since 1974, the latest in February 2008. We conducted an outbreak investigation using a case-control design. Sixty-seven cases of VOD were compared with 199 community controls. Consumption of bread was strongly associated with disease (adjusted odds ratio: 35.8 [95%CI: 7.6-168.2]). Toxic doses of PA were found in plant extracts and in samples of wheat flour taken from the study area. Compared to wheat flour there was 1000 times less PA in milk and whey and in water samples the PA content was zero. Although direct analysis was not possible, contaminated wheat flour used to make bread was the likely source of PA causing the outbreak. Eating a more varied diet including meat and fruit may be protective. Prevention and control measures will rely on community awareness and agricultural interventions to ensure safety of the food supply.

11.
Biosens Bioelectron ; 25(12): 2615-21, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20466534

RESUMO

A reliable and cost-effective electrochemical method for the detection of deoxynivalenol (DON) in cereals and cereal-based food samples based on the use of a novel anti-DON Fab fragment is presented. The analytical system employed, Enzyme-Linked-Immunomagnetic-Electrochemical (ELIME) assay, is based on the use of immunomagnetic beads (IMBs) coupled with eight magnetized screen-printed electrodes (8-mScPEs) as electrochemical transducers. Using standard solutions of DON, a working range between 100 and 4500 ng/ml was obtained with an EC(50) of 380 ng/ml. The ELIME assay was employed to evaluate the cross-reactivity of the Fab fragment towards different trichothecenes revealing a good selectivity towards DON over other trichothecenes with the exception of 3-Ac-DON. The sensor was then applied to cereals and cereal-based food samples (wheat, breakfast cereal and baby-food) and a wide range of sample treatment procedures was tested. Within-laboratory precision (9-24% repeatability for breakfast cereals and 10-33% for baby-food) and recovery data (82-110% for breakfast cereals and 97-108% for baby-food) were calculated by analyzing blank breakfast cereals and baby-foods fortified with DON, demonstrating that the proposed method has the capability for use as a screening assay for DON in such products.


Assuntos
Técnicas Biossensoriais/métodos , Contaminação de Alimentos/análise , Tricotecenos/análise , Animais , Anticorpos Imobilizados , Técnicas Biossensoriais/instrumentação , Grão Comestível/química , Técnicas Eletroquímicas , Humanos , Imunoensaio/métodos , Fragmentos Fab das Imunoglobulinas , Lactente , Alimentos Infantis/análise , Proteínas Recombinantes , Tricotecenos/imunologia , Triticum/química
12.
Anal Chem ; 82(7): 2977-88, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20232817

RESUMO

A research element of the European Union (EU) sixth Framework project BioCop focused on the development of a surface plasmon resonance (SPR) biosensor assay for the detection of paralytic shellfish poisoning (PSP) toxins in shellfish as an alternative to the increasingly ethically unacceptable mouse bioassay. A biosensor assay was developed using both a saxitoxin binding protein and chip surface in tandem with a highly efficient simple extraction procedure. The present report describes the single laboratory validation of this immunological screening method, for this complex group of toxins with differing toxicities, according to the European Decision 2002/657/EC in conjunction with IUPAC and AOAC single laboratory validation guidelines. The different performance characteristics (detection capability CCbeta, specificity/selectivity, repeatability, reproducibility, stability, and applicability) were determined in relation to the EU regulatory limit of 800 microg of saxitoxin equivalents (STX eq) per kg of shellfish meat. The detection capability CCbeta was calculated to be 120 microg/kg. Intra-assay repeatability was found to be between 2.5 and 12.3% and interassay reproducibility was between 6.1 and 15.2% for different shellfish matrices. Natural samples were also evaluated and the resultant data displayed overall agreements of 96 and 92% with that of the existing AOAC approved methods of mouse bioassay (MBA) and high performance liquid chromatography (HPLC), respectively.


Assuntos
Toxinas Marinhas/química , Ressonância de Plasmônio de Superfície/métodos , Animais , Anticorpos/química , Anticorpos/metabolismo , Bivalves/química , Cardiidae/química , Proteínas de Transporte/química , Toxinas Marinhas/análise , Saxitoxina/análise , Saxitoxina/química , Saxitoxina/imunologia , Intoxicação por Frutos do Mar
14.
Anal Bioanal Chem ; 388(5-6): 1215-26, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17551715

RESUMO

This paper presents results from the European Commission-funded project Doncalibrant, the objective of which was to produce calibrators with certified mass fractions of the Fusarium toxins deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-Ac-DON), 15-acetyldeoxynivalenol (15-Ac-DON), and nivalenol (NIV), in acetonitrile. The calibrators, available in ampoules, were sufficiently homogeneous, with between-bottle variations (s (bb)) of less than 2%. Long-term stability studies performed at four different temperatures between -18 and 40 degrees C revealed no significant negative trends (at a confidence level of 95%). Molar absorptivity coefficients (in L mol(-1) cm(-1)) were determined for all four toxins (DON: 6805 +/- 126, NIV: 6955 +/- 205, 3-Ac-DON: 6983 +/- 141, 15-Ac-DON: 6935 +/- 142) on the basis of a mini-interlaboratory exercise. The overall uncertainty of the calibrators' target values for DON and NIV were evaluated on the basis of gravimetric preparation data and include uncertainty contributions from possible heterogeneity, storage, and transport. The Doncalibrant project resulted in the production of calibrators for DON (IRMM-315) and NIV (IRMM-316) in acetonitrile with certified mass fractions of 25.1 +/- 1.2 microg g(-1) and 24.0 +/- 1.1 microg g(-1), respectively. Both CRMs became commercially available from the Institute for Reference Materials and Measurements (IRMM, Geel, Belgium) at the beginning of 2007.


Assuntos
Técnicas de Química Analítica/métodos , Tricotecenos/análise , Automação , Calibragem , Cromatografia Líquida , Fusarium/metabolismo , Modelos Químicos , Modelos Estatísticos , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta , Temperatura
15.
Anal Bioanal Chem ; 389(1): 147-57, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17508207

RESUMO

Regulations relating to mycotoxins have been established in many countries to protect the consumer from the harmful effects of these compounds. Different factors play a role in the decision-making process of setting limits for mycotoxins. These include scientific factors, for example the availability of toxicological data and occurrence data, detailed knowledge about possibilities for sampling and analysis, and socio-economic issues. By the end of 2003, approximately 100 countries (covering approximately 85% of the world's inhabitants) had specific regulations or detailed guidelines for mycotoxins in food. The regulations were related to aflatoxins (B(1), B(2), G(1) and G(2)), aflatoxin M(1), trichothecenes (deoxynivalenol, diacetoxyscirpenol, T-2 toxin and HT-2 toxin), fumonisins (B(1), B(2), and B(3)), agaric acid, ergot alkaloids, ochratoxin A, patulin, phomopsins, sterigmatocystin, and zearalenone. In Europe, and in particular in the EU, regulatory and scientific interest in mycotoxins has undergone a development in the last decade from autonomous national activity towards more EU-driven activity with a structural and network character. Harmonized EU limits now exist for 40 mycotoxin-food combinations. It is expected this number will grow in 2007 to approximately 50. The direct or indirect influence of European organizations and programs on the EU mycotoxin regulatory developments is significant. They include the European Food Safety Authority, the Scientific Cooperation on Questions relating to Food, the Rapid Alert System for Food and Feed, the creation of an EU Community Reference Laboratory for Mycotoxins and a mandate of the EC to the European Standardization Committee in methods for analysis for mycotoxins in food. Large pan-European research and networking projects as "BioCop" and "MoniQA" are also important.


Assuntos
Análise de Alimentos , Micotoxinas/análise , Europa (Continente) , Humanos , Internacionalidade , Medição de Risco
16.
J AOAC Int ; 90(6): 1598-609, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18193737

RESUMO

An interlaboratory trial for determination of zearalenone (ZON) in baby food and animal feed was conducted. The study involved 39 participants in 16 European Union member states, as well as Turkey, Uruguay, and China, representing a cross-section of industry, and official food control and research institutes. The method is based on immunoaffinity column cleanup followed by high-performance liquid chromatography using fluorimetry (HPLC-FI). The test portion of the sample is extracted with methanol-water (75 + 25, v/v). The sample extract is filtered, diluted, and passed over an immunoaffinity column. ZON is eluted with methanol. The separation and determination of ZON is performed by reversed-phase HPLC-FI with an excitation wavelength of 274 nm and an emission wavelength of 446 nm. Test portions of the samples were spiked at levels of 20 and 30 microg/kg ZON in baby food and at levels of 100 and 150 microg/kg ZON in animal feed. Mean recoveries from each participant ranged from 78 to 119% with an average value of 92% for baby food and from 51 to 122% with an average value of 74% for animal feed. Based on results for spiked samples (blind duplicates at 2 levels), as well as naturally contaminated samples (blind duplicates at 3 levels), the relative standard deviation for repeatability (RSDr) in baby food ranged from 2.8 to 9.0%. For animal feed, this value ranged from 5.7 to 9.5%. The relative standard deviation for reproducibility (RSDR) in baby food ranged from 8.2 to 13.3%, and for animal feed this value ranged from 15.5 to 21.4%. The Horwitz ratio (HorRat) in baby food ranged from 0.3 to 0.4, and for animal feed this value ranged from 0.6 to 0.9. The method showed acceptable within- and between-laboratory precision for each matrix, as required by European legislation.


Assuntos
Ração Animal/análise , Alimentos Infantis/análise , Micotoxinas/análise , Zearalenona/análise , Animais , Calibragem , Criança , Cromatografia Líquida de Alta Pressão , Humanos , Imunoquímica , Indicadores e Reagentes , Padrões de Referência , Reprodutibilidade dos Testes , Solventes , Espectrometria de Fluorescência
17.
Mol Nutr Food Res ; 51(1): 7-60, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17195276

RESUMO

Blue-green algae are found in lakes, ponds, rivers and brackish waters throughout the world. In case of excessive growth such as bloom formation, these bacteria can produce inherent toxins in quantities causing toxicity in mammals, including humans. These cyanotoxins include cyclic peptides and alkaloids. Among the cyclic peptides are the microcystins and the nodularins. The alkaloids include anatoxin-a, anatoxin-a(S), cylindrospermopsin, saxitoxins (STXs), aplysiatoxins and lyngbyatoxin. Both biological and chemical methods are used to determine cyanotoxins. Bioassays and biochemical assays are nonspecific, so they can only be used as screening methods. HPLC has some good prospects. For the subsequent detection of these toxins different detectors may be used, ranging from simple UV-spectrometry via fluorescence detection to various types of MS. The main problem in the determination of cyanobacterial toxins is the lack of reference materials of all relevant toxins. In general, toxicity data on cyanotoxins are rather scarce. A majority of toxicity data are known to be of microcystin-LR. For nodularins, data from a few animal studies are available. For the alkaloids, limited toxicity data exist for anatoxin-a, cylindrospermopsin and STX. Risk assessment for acute exposure could be relevant for some types of exposure. Nevertheless, no acute reference doses have formally been derived thus far. For STX(s), many countries have established tolerance levels in bivalves, but these limits were set in view of STX(s) as biotoxins, accumulating in marine shellfish. Official regulations for other cyanotoxins have not been established, although some (provisional) guideline values have been derived for microcystins in drinking water by WHO and several countries.


Assuntos
Toxinas Bacterianas/toxicidade , Cianobactérias/patogenicidade , Toxinas Marinhas/toxicidade , Microcistinas/toxicidade , Alcaloides , Toxinas Bacterianas/análise , Toxinas Bacterianas/química , Toxinas Bacterianas/metabolismo , Biodegradação Ambiental , Toxinas de Cianobactérias , Toxinas de Lyngbya/toxicidade , Toxinas Marinhas/análise , Toxinas Marinhas/química , Toxinas Marinhas/metabolismo , Microcistinas/análise , Microcistinas/química , Microcistinas/metabolismo , Peptídeos Cíclicos/toxicidade , Saxitoxina/toxicidade , Tropanos/toxicidade , Uracila/análogos & derivados , Uracila/toxicidade
18.
J AOAC Int ; 89(4): 1012-20, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16915838

RESUMO

An interlaboratory study was conducted for the determination of deoxynivalenol in baby food and animal feed by high-performance liquid chromatography with UV detection. The study included 14 participants representing a cross section of industry, official food control, and research facilities. Mean recoveries reported ranged from 89% (at 120 microg/kg) to 85% (at 240 microg/kg) for baby food and from 100% (at 200 microg/kg) to 93% (at 400 microg/kg) for animal feed. On the basis of the results for spiked samples (blind duplicates at 2 levels), as well as those for naturally contaminated samples (blind duplicates at 3 levels), the relative standard deviation for repeatability (RSDr) in analyses of baby food ranged from 6.4 to 14.0% and in analyses of animal feed, from 6.1 to 16.5%. The relative standard deviation for reproducibility (RSDR) in analyses of baby food ranged from 9.4 to 19.5% and in analyses of animal feed, from 10.5 to 25.2%. The HorRat values ranged from 0.4 to 1.0 and from 0.7 to 1.3, for baby food and animal feed, respectively. The method showed acceptable performance for within-laboratory and between-laboratory precision for each matrix, as required by European legislation.


Assuntos
Ração Animal/análise , Técnicas de Química Analítica/métodos , Cromatografia Líquida/métodos , Análise de Alimentos/métodos , Alimentos Infantis/análise , Tricotecenos/análise , Cromatografia Líquida de Alta Pressão , Contaminação de Alimentos , Modelos Estatísticos , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta
19.
J AOAC Int ; 89(3): 595-605, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16792057

RESUMO

A method was developed for the determination of aflatoxin B1 in medical herbs (senna pods, botanical name Cassia angustifolia; devil's claw, botanical name Harpagophytum procumbens; and ginger roots, botanical name Zingiber officinale). The method, which was tested in a mini-collaborative study by 4 laboratories, is based on an immunoaffinity cleanup followed by reversed-phase high-performance liquid chromatography separation and fluorescence detection after post-column derivatization. It allows the quantitation of aflatoxin B1 at levels lower than 2 ng/g. A second extractant (acetone-water) was tested and compared to the proposed methanol-water extractant. Several post-column derivatization options (electrochemically generated bromine, photochemical reaction, and chemical bromination) as well as different integration modes (height versus area) were also investigated. No differences were found depending on the choice of derivatization system or the signal integration mode used. The method was tested for 3 different matrixes: senna pods, ginger root, and devil's claw. Performance characteristics were established from the results of the study and resulted in HorRat values ranging from 0.12 to 0.75 with mean recoveries from 78 to 91% for the extraction with methanol-water and HorRat values ranging from 0.10-1.03 with mean recoveries from 98 to 103% for the extraction with acetone-water. As a result, the method, with all tested variations, was found to be fit-for-purpose for the determination of aflatoxin B1 in medical herbs at levels of 1 microg/kg and above.


Assuntos
Aflatoxina B1/análise , Aflatoxina B1/isolamento & purificação , Cassia/metabolismo , Técnicas de Química Analítica/métodos , Calibragem , Cromatografia de Afinidade/métodos , Cromatografia Líquida de Alta Pressão/métodos , Metanol/química , Fotoquímica , Reprodutibilidade dos Testes , Espectrometria de Fluorescência
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