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Gallart-Ayala H - Chéreau S - Dervilly-Pinel G - Le Bizec B
Potential of mass spectrometry metabolomics for chemical food safety (review)
This review aims to describe the most significant applications of mass spectrometry based metabolomics in the field of chemical food safety. A particular discussion of all the different analytical steps involved in the metabolomics workflow (sample preparation, mass spectrometry analytical platform and data processing) will be addressed. © 2015 Future Science Ltd.

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Kouassi Nzoughet J - Dervilly-Pinel G - Chéreau S - Biancotto G - Monteau F - Elliott CT - Le Bizec B
First insights into serum metabolomics of Revalor-XS® implanted bovines; Screening model to predict animals’ status
The use of anabolic agents in livestock production is a subject of much concern. Although prohibited for more than 20 years within the EU, growth promoting practices are still widely suspected. To meet the current challenges for detecting illicit practices, ‘omics’ strategies have recently been demonstrated as important new investigative tools. These investigations, based on the observation of physiological disturbances, mainly in urine, demonstrated the possibility to monitor biomarkers enabling high throughput determination of animal status in terms of hormonal treatment. In this context, serum was investigated for the first time as an alternative and potential complementary sample type. A metabolomic approach based on liquid chromatography coupled to high resolution mass spectrometry, was exploited in order to, highlight metabolic perturbations in serum of Revalor-XS® (trenbolone acetate/estradiol) implanted bovines. Univariate and multivariate statistical analyses were carried out to establish descriptive and predictive models. These models enabled the discrimination of anabolised from control animals, and highlighted a number of metabolites which contributed the most in the observed discrimination. Further, a screening model combining a set of selected markers intensities was generated and it successfuly classified animals according to their status, up to 4 weeks post Revalor-XS® implant. This research indicates, for the first time, that serum metabolomics has an important role in screening to detect for anabolic misuse in bovines. © Springer Science+Business Media New York 2015.

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Doué M - Dervilly-Pinel G - Pouponneau K - Monteau F - Le Bizec B
Direct analysis in real time - high resolution mass spectrometry (DART-HRMS): a high throughput strategy for identification and quantification of anabolic steroid esters
Drug Testing and Analysis
High throughput screening is essential for doping, forensic, and food safety laboratories. While hyphenated chromatography mass spectrometry (MS) remains the approach of choice, recent ambient MS techniques, such as direct analysis in real time (DART), offer more rapid and more versatile strategies and thus gain in popularity. In this study, the potential of DART hyphenated with Orbitrap-MS for fast identification and quantification of 21 anabolic steroid esters has been evaluated. Direct analysis in high resolution scan mode allowed steroid esters screening by accurate mass measurement (Resolution = 60 000 and mass error<3ppm). Steroid esters identification was further supported by collision-induced dissociation (CID) experiments through the generation of two additional ions. Moreover, the use of labeled internal standards allowed quantitative data to be recovered based on isotopic dilution approach. Linearity (R2>0.99), dynamic range (from1 to 1000 ng.mL-1), bias (<10%), sensitivity (1 ng.mL-1), repeatability and reproducibility (RSD<20%) were evaluated as similar to those obtained with hyphenated chromatography-mass spectrometry techniques. This innovative high throughput approach was successfully applied for the characterization of oily commercial preparations, and thus fits the needs of the competent authorities in the fight against forbidden or counterfeited substances. © 2014 John Wiley & Sons, Ltd.

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Couderc M - Poirier L - Zalouk-Vergnoux A - Kamari A - Blanchet-Letrouvé I - Marchand P - Venisseau A - Veyrand B - Mouneyrac C - Le Bizec B
Occurrence of POPs and other persistent organic contaminants in the European eels (Anguilla anguilla) from the Loire estuary, France
Science of the Total Environment
The chemical contamination of the Loire estuary by three classes of persistent organic pollutants (POPs): the polychlorinated biphenyls (PCBs), the polybrominated diphenyl ethers (PBDEs) and the perfluorinated and polyfluorinated alkyl substances (PFAS), and three families of organic contaminants, the alkylphenols (APs), the polycyclic aromatic hydrocarbon metabolites (OH-PAHs) and the bisphenol A (BPA) were investigated in the muscles and bile of European eel (Anguilla anguilla). Yellow eels (n = 30) were caught in three different points along the estuary to highlight variations between sites and sources of contaminations. Silver eels (n = 15) were also studied to compare contaminant impregnation between different life stages of the species. Average concentrations in the muscles of the eel ranged between: 857 and 4358 ng/g LW for the PCBs, 26 and 46 ng/g LW for the PBDEs, 130 and 1293 ng/g LW for the PFAS; and in bile: 31 and 286 μg/g protein for the APs, 9 and 26 μg/g protein for the OH-PAHs and ND-1213 μg/g protein for the BPA. Among PCBs, PCB 153 (40% contribution to the sum of PCBs) was predominant in all eel muscles. PBDE 47 (60%) was the most predominant PBDE congeners, while perfluorooctanesulfonic acid (85%) was the most widely detected PFAS. For APs, 4p-nonylphenol (91%) was the most abundant and for the OH-PAHs, it was 1OH-Pyrene (63%). All the eels exceeded the environmental quality standards (EQS) for biota for the PBDEs and about 75% were higher than the EQS specific to PFOS. Finally, 20% of the analyzed eels presented TEQ concentrations above the maximum limits for lipid-rich species. These results supplied new data on the occurrence, levels, and patterns of 53 organic chemicals in the eels from the Loire estuary and they highlighted the need of further investigations focused notably on the potential effects of these chemicals on this species and their analysis in the water and sediments of the estuary. © 2014 Elsevier B.V. All rights reserved.

10(2): e0117226. doi:10.1371/journal.pone.0117226
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Ben Maamar M - Lesné L - Desdoits-Lethimonier C - Coiffec I - Lassurguère J - Lavoué V - Deceuninck Y - Antignac JP - Le Bizec B - Perdu E - Zalko D - Pineau C - Chevrier C - Dejucq-Rainsford N - Mazaud-Guittot S - Jégou B
An investigation of the endocrine-disruptive effects of bisphenol A in human and rat fetal testes
Few studies have been undertaken to assess the possible effects of bisphenol A (BPA) on the reproductive hormone balance in animals or humans with often contradictory results. We investigated possible direct endocrine disruption by BPA of the fetal testes of 2 rat strains (14.5–17.5 days post-coitum) and humans (8–12 gestational weeks) and under different culture conditions. BPA concentrations of 10-8M and 10-5M for 72h reduced testosterone production by the Sprague-Dawley fetal rat testes, while only 10-5M suppressed it in the Wistar strain. The suppressive effects at 10-5M were seen as early as 24h and 48h in both strains. BPA at 10-7-10-5M for 72h suppressed the levels of fetal rat Leydig cell insulinlike factor 3 (INSL3). BPA exposure at 10-8M, 10-7M, and 10-5M for 72h inhibited testosterone production in fetal human testes. For the lowest doses, the effects observed occurred only when no gonadotrophin was added to the culture media and were associated with a poorly preserved testicular morphology. We concluded that (i) BPA can display antiandrogenic effects both in rat and human fetal testes; (ii) it is essential to ascertain that the divergent effects of endocrine disruptors between species in vitro do not result from the culture conditions used, and/or the rodent strain selected; (iii) the optimization of each in vitro assay for a given species should be a major objective rather than the search of an hypothetical trans-species consensual model-system, as the organization of the testis is intrinsically different between mammalian species; (iv) due to the uncertainty existing on the internal exposure of the human fetal testis to BPA, and the insufficient number of epidemiological studies on the endocrine disruptive effects of BPA, caution should be taken in the extrapolation of our present results to the human reproductive health after fetal exposure to BPA.

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Boué G - Guillou S - Antignac JP - Le Bizec B - Membré JM
Public health Risk-Benefit Assessment associated with food consumption: a review
European Journal of Nutrition and Food Safety
Background: In the food safety field, risk assessment, including microbial and chemical components, has been applied for many years. However, a whole and integrated public health assessment also depends on the nutritional composition of food. While the fact that foods and diets can be a source of both risks and benefits now appears undisputed, carrying out a risk-benefit assessment (RBA) is still an emerging and challenging scientific subject. Aims: The purpose of the present review was to synthesize RBA studies associated with food consumption and to summarize the current methodological options and/or tendencies carried out in this field. Methods: The different data sources explored included around 20 accessible databases using the main terms “risk”, “benefit” and “food” as keyword enquiries in article title and full-text. The initial research process led to 3293 screened papers, 160 of which were examined in detail. Results: There were 126 articles dealing with RBA studies and 34 with the RBA methodological framework. Most of the available papers dealt with the comparison of nutritional beneficial effects and chemical adverse effects related to fish consumption. The majority of studies undertook a comparison of consumer exposure to risks and benefits with regard to reference safety values. However, more varied studies have emerged during the last 15 years, contributing to the diversification and the development of this issue. Conclusion: RBA appears to be a promising scientific discipline and should be the next step in assessing the overall impact of food on health.

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Denys S - Fraize-Frontier S - Moussa O - Le Bizec B - Veyrand B - Volatier JL
Is the fresh water fish consumption a significant determinant of the internal exposure to perfluoroalkylated substances (PFAS)?
Toxicology Letters
PFAS are man-made compounds that are highly spread in the environment. Human dietary exposure to such contaminants is of high concern as they may accumulate in the food chain. Different studies already demonstrated the importance of the fish consumption in the dietary exposure of these molecules and the potential increase of internal doses of PFAS following the consumption of PFAS. However, so far few study aimed to study the link between the consumption of fresh water fishes and the internal exposure to PFAS. Objectives of this study were (i) to estimate the internal exposure of populations that are potentially high consumers of fresh water fishes and (ii) to determine whether the consumption of fish caught from fresh water is a significant determinant of the internal exposure of PFAS. In this work, a large sample of adult freshwater anglers from the French metropolitan population (478 individuals) was constituted randomly from participants lists of anglers associations. Questionnaires provided social and demographic information and diet information for each subject. In addition, analyses of blood serum samples provided the internal concentration of 14 PFAS. The survey design allowed to extrapolate the data obtained on the 478 individuals to the freshwater angler population. Descriptive data regarding internal levels of PFAS were discussed at the population level, whereas identification of the determinants were done at the 478 individuals level as sufficient contrast was required in terms of fresh water fish consumption. Only molecules for which the detection frequency were above 80% in blood were considered, i.e., PFOS, PFOA, PFHxS, PFNA, PFHpS, and PFDA. Distribution profiles showed log-normal distribution and PFOS and PFOA were the main contributors of the PFAS sum. For PFOS, the results obtained on the 478 individuals showed that upper percentiles were higher as compared to upper percentiles obtained on occidental general population. This confirmed an over-exposure of a fraction of the 478 individuals. Though, when the results were considered at the population level, the values were close. This was attributed to the low consumption frequency of fresh water fish in the general population. For PFOS, PFNA, PFHxS, PFHpS and PFDA, the fresh water fish consumption was identified as one of the contributors of internal PFAS concentrations. Gender, age, geographical location and consumption of home-grown products as other determinants were also discussed in this paper. © 2014 Elsevier Ireland Ltd. All rights reserved.

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Nunes M - Venisseau A - Marchand P - Le Bizec B - Ramos F - Pardal MA
Occurrence of PCDD/Fs and dioxin-like PCBs in superficial sediment of Portuguese estuaries
Environmental Science and Pollution Research
Superficial sediments collected from seven estuarine systems located along the Portuguese coast were analyzed for 7 polychlorinated dibenzo-p-dioxins (PCDDs), 10 polychlorinated dibenzofurans (PCDFs), and 12 dioxin-like polychlorinated biphenyls (dl-PCBs). Total PCDD/F concentration ranged from 4.6 to 464 pg.g-1 dry weight (dw), while that of dl-PCBs varied from 26.6 to 8,693 pg.g-1 dw. In general, the highest PCDD/F and dl-PCB concentrations were associated with densely populated and industrially impacted areas. Additionally, PCDD/F revealed a predominance of octachlorodibenzodioxin (OCDD) to total PCDD/Fs, while PCB 118 was the major contributor to total dl-PCBs. This study provided a global perspective of the contamination status of Portuguese estuaries by dioxin-like compounds and allowed a comparison between the investigated systems and other systems worldwide. PCDD/F and dl-PCB levels found in the collected sediments were lower than those of highly impacted areas from different parts of the globe. Nevertheless, comparison with guidelines and quality standards from other countries indicated that some Portuguese estuarine areas with a high industrialization level present PCDD/F and dl-PCB concentrations in superficial sediment that may constitute a risk to aquatic organisms. © Springer-Verlag Berlin Heidelberg 2014.

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Jacquet R - Miege C - Smedes F - Tixier C - Tronczynski J - Togola A - Berho C - Valor I - Llorca J - Barillon B - Marchand P - Coquery M
Comparison of five integrative samplers in laboratory for the monitoring of indicator and dioxin-like polychlorinated biphenyls in water
This study aimed at evaluating and comparing five integrative samplers for the monitoring of indicator and dioxin-like polychlorinated biphenyls (PCBs) in water: semi-permeable membrane device (SPMD), silicone rubber, low-density polyethylene (LDPE) strip, Chemcatcher and a continuous-flow integrative sampler (CFIS). These samplers were spiked with performance reference compounds (PRCs) and then simultaneously exposed under constant agitation and temperature in a 200 L stainless steel tank for periods ranging from one day to three months. A constant PCB concentration of about 1 ng.L-1 was achieved by immersing a large amount of silicone rubber sheets (‘‘dosing sheets’’) spiked with the target PCBs. The uptake of PCBs in the five samplers showed overall good repeatability and their accumulation was linear with time. The samplers SPMD, silicone rubber and LDPE strip were the most promising in terms of achieving low limits of quantification. Time-weighted average (TWA) concentrations of PCBs in water were estimated from uptake of PCBs using the sampling rates calculated from the release of PRCs. Except for Chemcatcher, a good agreement was found between the different samplers and TWA concentrations ranged between 0.4 and 2.8 times the nominal water concentration. Finally, the influence of calculation methods (sampler-water partition coefficients, selected PRCs, models) on final TWA concentrations was studied. © 2013 Elsevier Ltd. All rights reserved.

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Bemrah N - Jean J - Rivière G - Sanaa M - Leconte S - Bachelot M - Deceuninck Y - Le Bizec B - Dauchy X - Roudot AC - Camel V - Grob K - Feidt C - Hagen-Picard N - Badot PM - Foures F - Leblanc JC
Assessment of dietary exposure to bisphenol A in the French population with a special focus on risk characterisation for pregnant French women
Food and Chemical Toxicology
Bisphenol A (BPA) is used in a wide variety of products and objects for consumers use (digital media such as CD’s and DVD’s, sport equipment, food and beverage containers, medical equipment). Here, we demonstrate the ubiquitous presence of this contaminant in foods with a background level of contamination of less than 5 µg/kg in 85% of the 1498 analysed samples. High levels of contamination (up to 400 µg/kg) were found in some foods of animal origin. We used a probabilistic approach to calculate dietary exposure from French individual consumption data for infants under 36 months, children and adolescents from 3 to 17 years, adults over 18 years and pregnant women. The estimated average dietary exposure ranged from 0.12 to 0.14 µg/kg body weight per day (bw/d) for infants, from 0.05 to 0.06 µg/kg bw/d for children and adolescents, from 0.038 to 0.040 µg/kg bw/d for adults and from 0.05 to 0.06 µg/kg bw/d for pregnant women. The main sources of exposure were canned foods (50% of the total exposure), products of animal origin (20%) and 30% as a background level. Based on the toxicological values set by the French Agency for Food, Environmental and Occupational Health & Safety (ANSES) for pregnant women, the risk was non negligible. Thus, we simulated scenarios to study the influence of cans and/or food of animal origin on the BPA-related risk for this specific population. ©2014 Elsevier Ltd. All rights reserved.

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