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1.
EFSA J ; 15(7): e04908, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32625569

RESUMEN

EFSA was asked by the European Commission to deliver a scientific opinion on the risks for human health related to the presence of pyrrolizidine alkaloids (PAs) in honey, tea, herbal infusions and food supplements and to identify the PAs of relevance in the aforementioned food commodities and in other feed and food. PAs are a large group of toxins produced by different plant species. In 2011, the EFSA Panel on Contaminants in the Food Chain (CONTAM Panel) assessed the risks related to the presence of PAs in food and feed. Based on occurrence data limited to honey, the CONTAM Panel concluded that there was a possible health concern for those toddlers and children who are high consumers of honey. A new exposure assessment including new occurrence data was published by EFSA in 2016 and was used to update the risk characterisation. The CONTAM Panel established a new Reference Point of 237 µg/kg body weight per day to assess the carcinogenic risks of PAs, and concluded that there is a possible concern for human health related to the exposure to PAs, in particular for frequent and high consumers of tea and herbal infusions. The Panel noted that consumption of food supplements based on PA-producing plants could result in exposure levels too close (i.e. less than 100 times lower) to the range of doses known to cause severe acute/short term toxicity. From the analysis of the available occurrence data, the CONTAM Panel identified a list of 17 PAs of relevance for monitoring in food and feed. The Panel recommended continuing the efforts to monitor the presence of PAs in food and feed, including the development of more sensitive and specific analytical methods. A recommendation was also issued on the generation of data to identify the toxic and carcinogenic potency of the PAs commonly found in food.

2.
J Agric Food Chem ; 56(15): 6031-8, 2008 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-18624435

RESUMEN

The discovery of acrylamide (AA) in many common cooked starchy foods has presented significant challenges to toxicologists, food scientists, and national regulatory and public health organizations because of the potential for producing neurotoxicity and cancer. This paper reviews some of the underlying experimental bases for AA toxicity and earlier risk assessments. Then, dietary exposure modeling is used to estimate probable AA intake in the U.S. population, and physiologically based pharmacokinetic/pharmacodynamic (PBPK/PD) modeling is used to integrate the findings of rodent neurotoxicity and cancer into estimates of risks from human AA exposure through the diet. The goal of these modeling techniques is to reduce the uncertainty inherent in extrapolating toxicological findings across species and dose by comparing common exposure biomarkers. PBPK/PD modeling estimated population-based lifetime excess cancer risks from average AA consumption in the diet in the range of 1-4 x 10 (-4); however, modeling did not support a link between dietary AA exposure and human neurotoxicity because marginal exposure ratios were 50-300 lower than in rodents. In addition, dietary exposure modeling suggests that because AA is found in so many common foods, even big changes in concentration for single foods or groups of foods would probably have a small impact on overall population-based intake and risk. These results suggest that a more holistic analysis of dietary cancer risks may be appropriate, by which potential risks from AA should be considered in conjunction with other risks and benefits from foods.


Asunto(s)
Acrilamida/toxicidad , Dieta , Modelos Biológicos , Acrilamida/farmacocinética , Acrilamida/farmacología , Animales , Carcinógenos/química , Exposición a Riesgos Ambientales/análisis , Contaminación de Alimentos/análisis , Calor , Humanos , Neoplasias/inducido químicamente , Medición de Riesgo
3.
Artículo en Inglés | MEDLINE | ID: mdl-18311619

RESUMEN

Furan is a suspected human carcinogen that is formed in some processed foods at low ng per g levels. Recent improvements in analytical methodology and scientific instrumentation have made it possible to accurately measure the amount of furan in a wide variety of foods. Results from analysis of more than 300 processed foods are presented. Furan was found at levels ranging from non-detectable (LOD, 0.2-0.9 ng g(-1)) to over 100 ng g(-1). Exposure estimates for several adult food types were calculated, with brewed coffee being the major source of furan in the adult diet (0.15 microg kg(-1) body weight day(-1)). Estimates of mean exposure to furan for different subpopulations were calculated. For consumers 2 years and older, the intake is estimated to be about 0.2 microg kg(-1) body weight day(-1).


Asunto(s)
Carcinógenos/análisis , Contaminación de Alimentos/análisis , Manipulación de Alimentos , Furanos/análisis , Adulto , Carcinógenos/toxicidad , Café , Furanos/toxicidad , Cromatografía de Gases y Espectrometría de Masas/métodos , Calor , Humanos , Productos de la Carne
4.
J AOAC Int ; 88(1): 16-25, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15759721

RESUMEN

Kava (Piper methysticum) dietary products have been sold worldwide for treatment of nervous anxiety, tension, and restlessness. Recent reports showed potential association of kava usage and liver injuries. This study was conducted to develop simple and reliable methodologies for the extraction and determination of 6 major kavalactones: (+)-methysticin, (+)-dihydromethysticin, (+)-kavain, (+)-dihydrokavain, yangonin, and desmethoxyyangonin. Ultrasonic extraction techniques and isocratic reversed-phase liquid chromatography (LC) were optimized for different types of samples, including capsules containing kava root extract or root powder, raw root material, tea bags, and snack bar. A suitable internal standard, 5,7-dihydroxyflavone, was used for LC calibration. Kavalactones were completely separated in 30 min using a Luna C18-2 column at 60 degrees C with an isocratic mobile phase consisting of 2-propanol-acetonitrile-water-acetic acid (16 + 16 + 68 + 0.1, v/v/v/v). Within-laboratory, intraday, and interday method variation (% relative standard deviation) for most samples extracted by methanol or methanol-water mixture were <5%. Lower levels of kavalactone contents and higher variations were observed for tea bags from water extraction or infusion as compared to methanol extraction. Labeling information of tea bags based on methanol extraction could be misleading to consumers. Analytical recoveries of snack bar fortified at 10 and 20 microg/g were >84% with RSD values <8%. Methods developed in this study offer a simple and reproducible means for analysis of kavalactones in various matrixes of dietary products.


Asunto(s)
Cromatografía Liquida/métodos , Suplementos Dietéticos , Análisis de los Alimentos/métodos , Kava/metabolismo , Lactonas/análisis , Lactonas/química , Calibración , Alimentos , Modelos Químicos , Raíces de Plantas , Piranos/análisis , Pironas/análisis , , Temperatura , Factores de Tiempo
5.
J Agric Food Chem ; 52(20): 6156-64, 2004 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-15453681

RESUMEN

Several bioactive botanicals including St. John's wort (SJW; Hypericum perforatum L.) have been used to formulate functional foods and beverages. This study aimed to investigate the stability of SJW components in aqueous solutions and fruit-flavored drinks. Changes of active marker components (hypericin, pseudohypericin, hyperforin, and adhyperforin) as affected by pH and light exposure were determined by HPLC, and the degradation of hyperforin was analyzed by LC-MS/MS and NMR. SJW components were found to be unstable in acidic aqueous solutions. More changes occurred under light exposure, with hyperforin and adhyperforin decreasing the most. Less severe changes were observed in the drink sample as compared to the pH 2.65 solution. Major degradation products of hyperforin in acidic aqueous solutions were identified as furohyperforin, furohyperforin hydroperoxide, and furohyperforin isomer a. The latter was also found in the drink product containing SJW as an ingredient. Biological activities and potential quality and safety implications of these chemical changes are yet to be evaluated.


Asunto(s)
Bebidas/análisis , Compuestos Bicíclicos con Puentes/química , Hypericum/química , Floroglucinol/análogos & derivados , Floroglucinol/química , Terpenos/química , Estabilidad de Medicamentos , Concentración de Iones de Hidrógeno , Estructura Molecular , Soluciones , Agua
6.
J AOAC Int ; 87(4): 815-26, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15295874

RESUMEN

Ginkgo biloba leaf extract has been widely used in dietary supplements and more recently in some foods and beverages. Sample preparation procedures for determination of ginkgo terpene trilactones (including bilobalide and ginkgolides A, B, C, and J) in various sample matrixes were developed in this study. Ginkgo leaves and capsules were extracted with 5% KH2PO4 aqueous solution under sonication. Tea bags were extracted with boiling water, whereas drink samples were taken directly from the bottles. After filtration and the addition of NaCl to approximately 30% (w/v), the terpene trilactones in aqueous solutions were quantitatively extracted with ethyl acetate-tetrahydrofuran (4 + 1, v/v). Puff samples (a cereal-based fried snack item) were first defatted by using hexane or by using supercritical fluid extraction and then extracting under sonication with methanol-acetic acid (99 + 1, v/v). After evaporation of the organic phase, the terpene trilactones were redissolved in methanol and determined on a C18 reversed-phase column by liquid chromatography (LC) with evaporative light-scattering detection. The method of standard additions and gas chromatography with flame ionization detection were used for method validation. For most samples, the relative standard deviation was <10%. The identities of target compounds in ginkgo leaves and drink samples were confirmed by LC/electrospray ionization-tandem mass spectrometry.


Asunto(s)
Bebidas/análisis , Suplementos Dietéticos/análisis , Análisis de los Alimentos , Ginkgo biloba/química , Lactonas/análisis , Terpenos/análisis , Algoritmos , Calibración , Cápsulas , Cromatografía de Gases , Cromatografía Liquida , Indicadores y Reactivos , Lactonas/aislamiento & purificación , Hojas de la Planta/química , Estándares de Referencia , Dispersión de Radiación , Solventes , Espectrometría de Masa por Ionización de Electrospray , Terpenos/aislamiento & purificación
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