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278 résultat(s) trouvé(s)
2013;93(1):35–47
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P255
Mc Alister DR - Cariou R - Dindal A - Billets S
Application of an aryl hydrocarbon receptor based screening assay for assessing U.S. EPA draft remediation goals for dioxin in soil and sediment samples
International Journal of Environmental Analytical Chemistry
An aryl hydrocarbon receptor (AhR)-based, real-time polymerase chain reaction (PCR) assay (Procept®) was used to determine dioxin-like compounds in soil and sediment samples from seven sites known to be contaminated by dioxin and related compounds. The biological equivalent quotient (BEQ) generated by the Procept® assay was compared with toxicity equivalent (TEQ) measurements by isotope dilution gas chromatography-mass spectrometry (GC-MS). This research demonstrated that the Procept® assay has several limitations, when compared with GC-MS, including poorer detection limits and precision, and increased sensitivity to a wide range of AhR agonists and antagonists, such as polycyclic aromatic hydrocarbons (PAH) and polychlorinated biphenyls (PCBs). However, results indicate that the Procept® assay can be used as an effective screening technique for dioxin-like compounds at the EPA draft recommended interim preliminary remediation level for dioxin in soils of 72 pg/g TEQ. © 2013 Taylor & Francis.

2015;505:623–632
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P253
Desvignes V - Volatier JL - De Bels F - Zeghnoun A - Favrot MC - Marchand P - Le Bizec B - Rivière G - Leblanc JC - Merlo M
Study on polychlorobiphenyl serum levels in French consumers of freshwater fish
Science of the Total Environment
Introduction: Polychlorobiphenyls (PCBs) are persistent pollutants that are widespread in the environment and in foodstuffs, particularly in freshwater fish, which frequently exceed the maximum levels set by European regulations. Objectives: First, we describe the consumption of freshwater fish and serum PCB levels in French anglers, a population expected to have the highest level of dietary PCB exposure. Second, we investigated whether there is a statistical relationship between serum PCB levels and the angler consumption of freshwater fish with high PCB bioaccumulation potential (PCB-BP+ freshwater fish) in order to make recommendations with regard to safe consumption of freshwater fish. Methods: We conducted a survey of anglers from six sites with contrasting PCB contamination levels. The survey included a food consumption frequency questionnaire and blood samples were taken to assess serum PCB levels. We used a regression model to determine the main factors contributing to serum PCB levels. Results: Consumption of PCB-BP+ freshwater fish was relatively infrequent. Serum PCB levels of the study population and of women of childbearing age were in the same range as those observed in the French population and in neighboring European countries, but higher than in the North American population. The two factors with the highest positive association with serum PCB levels were age (R2=61%) and the consumption of PCB-BP+ freshwater fish (R2=2%). Using the regression model, we calculated, for several scenarios depending on the age and gender of the population, the maximum annual frequencies for PCB-BP+ freshwater fish consumption that do not exceed the critical body burden threshold. Conclusion: Following the results of this study, the French agency for food, environmental and occupational health and safety (ANSES) issued an opinion and recommended some specific maximum fresh water fish consumption frequencies to protect the French general population. © 2014 Elsevier B.V. All rights reserved.

2014;491–492:170–175
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P252
Yamada A - Bemrah N - Veyrand B - Pollono C - Merlo M - Desvignes V - Sirot V - Marchand P - Berrebi A - Cariou R - Antignac JP - Le Bizec B - Leblanc JC
Dietary exposure to perfluorinated alkyl acids of specific French sub-populations: high seafood consumers, high freshwater fish consumers and pregnant women
Science of the total environment
Contamination levels and profiles of 7 polychlorinated-p-dioxins, 10 polychlorinated furans (PCDD/Fs) and 12 dioxin-like polychlorinated biphenyls (dl-PCBs) were investigated in juvenile European flounder (Platichthys flesus) captured in different nursery areas in the northeastern Atlantic coast across its geographical distribution range. The toxic equivalent concentrations (WHO-TEQfish) were also determined in order to evaluate which P. flesus population was more exposed to dioxin-like toxicity. Juveniles caught in the Sørfjord (Norway) showed the lowest WHO-TEQfish concentration (0.052 pg WHO-TEQfish g-1 wet weight) whereas the highest value was observed in fish from the Wadden Sea (The Netherlands; 0.291 pg WHO-TEQfish g-1 ww), mainly due to the greater contribution of 2,3,7,8-tetrachlorodibenzo-p-dioxin, the most toxic congener. Nonetheless, when comparing the results with existent tissue residue-based toxicity benchmarks, no adverse effects resulting from PCDD/Fs and dl-PCBs are expected to occur in flounder from the studied systems. © 2014 Elsevier Ltd. All rights reserved.

2014;85:292–296
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P251
Nunes M - Martinho F - Venisseau A - Marchand P - Le Bizec B - Van der Veer HW - Cabral HN - Ramos F - Pardal MA
Early contamination of European flounder (Platichthys flesus) by PCDD/Fs and dioxin-like PCBs
Marine Polution Bulletin

2014:10(4):627-637
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P250
Da Costa Jacob C - Dervilly-Pinel G - Biancotto G - Le Bizec B
Evaluation of specific gravity as normalization strategy for cattle urinary metabolome analysis
Metabolomics
Urine is an ideal biofluid for metabolomics studies since it is obtained noninvasively, and its composition is affected by genetic and environmental factors reflecting the physiology of multiple organs. However, urine dilution effects and instrumental variation from the analytical method play a significant confounding role when one attempts to characterize biological and physiological factors through NMR and MS measurements of small molecule concentrations. Several normalization approaches have been used for urinary metabolomics studies and normalization to osmolality or to total useful MS signal have been proposed. When dealing with urinary metabolome analysis in cattle, freeze-drying (FD) is the method commonly used for normalization purposes. Herein, normalization to specific gravity, which provides a fair estimation of urine osmolality, was compared to the time consuming FD step and to the normalization to total useful MS signal in order to assess if this approach could be used as normalization strategy to differentiate control from anabolic treated animals. The results revealed that  80 % of the metabolites detected as constituting the acquired MS fingerprints for the freeze-dried samples and for the samples normalized to both specific gravity (SG) and total useful MS signal were in common. In addition, similar information from the multivariate statistical analysis was obtained by both normalization approaches. We demonstrate, therefore, that SG can be used as normalization approach for urinary metabolome analysis in cattle resulting in a high sample throughput procedure when compared with the FD step. © Springer Science+Business Media New York 2013.

2013:13.5:1302-1308
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P249
Barritaud L - Leroy G - Chachignon M - Ingrand V - Roche P - Bichon E - Gervais G - Bourgin M - Antignac JP - Monteau F - Le Bizec B
Identification of treatment by-products of the ozonation of estrone sulfate
Water Science & Technology: Water Supply
This article presents a methodology developed in order to identify the potential by-products of emerging chemical pollutants generated during oxidation treatments like chlorination and ozonation. As an example, the study of ozonated real river water samples spiked with estrone sulfate (E1-S) was used to evaluate the impact of ozonation on E1-S concentration and to identify the generated treatment by-products (TBPs). After a large-scale solid phase extraction, samples were analyzed by liquid chromatography coupled with high resolution mass spectrometry (HRMS) and data were processed according to a differential metabolomic-like approach to uncover the produced compounds. Four main TBPs were found. ERα-CALUX bioassays were performed to measure the estrogenic potency of samples before and after treatment. Results show that the estrogenic potency decreases drastically in drinking water with ozonation. © IWA Publishing 2013.

2013;30(12):2108–2113
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P248
Porphyre V - Rakotoharinome M - Randriamparany T - Pognon D - Prevost S - Le Bizec B
Residues of medroxyprogesterone acetate detected in sows at a slaughterhouse, Madagascar
Food Additives and Contaminants
In Madagascar, little information about drug residues in animal products is available. However, recently, official veterinary services were informed about the misuse of human injectable contraceptives in pig farms as an alternative for chirurgical castration of adult sows before culling. We investigated pigs (n = 80) slaughtered in 7 Malagasy abattoirs and raised in 8 of the 22 Malagasy regions (1) to confirm the contamination of carcasses by anabolic hormones by using LC-MS/MS, (2) to identify the substances of concern and (3) to explore the consumers’ exposure to hormone residues. Medroxyprogesterone acetate was the only synthetic hormone detected in kidney fat. Samples positive with medroxyprogesterone acetate were observed in 66.7% of the districts investigated and in 87.5% of the surveyed regions, confirming its large misuse in livestock. Public awareness campaigns and control improvement among the animal production sector and among the Malagasy public health sector are therefore urgent. © 2013 Taylor & Francis.

2014;53:1-10
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P247
Dervilly-Pinel G - Prevost S - Monteau F - Le Bizec B
Recombinant bovine somatotropin: an overview of analytical strategies to detect its use in food producing animals
TraC Trends in Analytical Chemistry
Recombinant bovine somatotropin (rbST) is produced in large quantities and widely used in a number of countries worldwide to stimulate milk production and as a general growth promoter in meat-producing animals. The use of this compound in animal production is strictly regulated by food-safety directives, particularly in the European Union. We give an overview of the state of the art in the detection of rbST-treated animals. © 2013 Elsevier B.V. All rights reserved.

Sous presse, 2014
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P246
Polychlorinated dibenzo-p-dioxins, furans and biphenyls (PCDDs/PCDFs, PCBs) in breast milk and early childhood growth and IGF-I
Reproduction
Experimental studies have shown that dioxin-like chemicals may interfere with aspects of the endocrine system including growth. However, human background population studies are, however, scarce. We aimed to investigate whether early exposure of healthy infants to dioxin-like chemicals was associated with changes in early childhood growth and serum IGF1. In 418 maternal breast milk samples of Danish children (born 1997–2001) from a longitudinal cohort, we measured polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and polychlorinated biphenyls (pg or ng/g lipid) and calculated total toxic equivalent (total TEQ). SDS and SDS changes over time (SDS) were calculated for height, weight, BMI, and skinfold fat percentage at 0, 3, 18, and 36 months of age. Serum IGF1 was measured at 3 months. We adjusted for confounders using multivariate regression analysis. Estimates (in parentheses) correspond to a fivefold increase in total TEQ. TEQ levels in breast milk increased significantly with maternal age and fish consumption and decreased with maternal birth year, parity, and smoking. Total TEQ was associated with lower fat percentage (K0.45 S.D., CI:K0.89; K0.04), non-significantly with lower weight and length at 0 months, accelerated early height growth (increased SDS) (SDS 0–18 months:C0.77 S.D., CI: 0.34; 1.19) and early weight increase (SDS 0–18:C0.52 S.D., CI: 0.03; 1.00), and increased IGF1 serum levels at 3 months (C13.9 ng/ml, CI: 2.3; 25.5). Environmental exposure to dioxin-like chemicals was associated with being skinny at birth and with higher infant levels of circulating IGF1 as well as accelerated early childhood growth (rapid catch-up growth). © 2014 Society for Reproduction and Fertility.

2013;61:7242-7249
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P243
Janssens G - Mangelinckx S - Courtheyn D - Prevost S - De Poorter G - De Kimpe N - Le Bizec B
Application of Gas Chromatography−Mass Spectrometry/2 Combustion/Isotope Ratio Mass Spectrometry (GC-MS/C/IRMS) to 3 Detect the Abuse of 17β-Estradiol in Cattle.
Journal of Agricultural and Food Chemistry
Although the ability to differentiate between endogenous steroids and synthetic homologues on the basis of their 13C/12C isotopic ratio has been known for over a decade, this technique has been scarcely implemented for food safety purposes. In this study, a method was developed using gas chromatography−mass spectrometry/combustion/isotope ratio mass spectrometry (GC-MS/C/IRMS) to demonstrate the abuse of 17β-estradiol in cattle, by comparison of the 13C/12C ratios of the main metabolite 17α-estradiol and an endogenous reference compound (ERC), 5-androstene-3β,17α-diol, in bovine urine. The intermediate precisions were determined as 0.46 and 0.26‰for 5-androstene-3β,17α-diol and 17α-estradiol, respectively. This is, to the authors’ knowledge, the first reported use of GC-MS/C/IRMS for the analysis of steroid compounds for food safety issues. © 2013 American Chemical Society.

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