References of "Eppe, Gauthier"
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See detailInnovative analytical strategy using ion-mobility for structural or functional selenium isomers identification by ion mobility spectrometry
Far, Johann ULg; Kune, Christopher ULg; Lobinski, Ryszard et al

Poster (2013, July)

Selenium (Se) is a trace element which is both essential and toxic depending on its concentration and its chemical form. Se-rich yeast is one of the most popular Se source for supplementation. The ... [more ▼]

Selenium (Se) is a trace element which is both essential and toxic depending on its concentration and its chemical form. Se-rich yeast is one of the most popular Se source for supplementation. The classical method of speciation is related to multidimensional liquid chromatography (LC) hyphenated to mass spectrometry (MS) Recent advances in Se speciation led to greatly improve the Se speciation in these samples but isomers identification and quantification remain challenging. This work focuses on the elaboration of an innovative analytical strategy for the detection and the structural elucidation of isobaric selenium compounds present in Se-rich yeast. A specific complex formation agent acts as a chemical probe for the detection of chemical function. The addition of a complexing agent can improve the discrimination between structural or functional Se isomers using ion mobility techniques as Ion Mobility Spectrometry (IMS) by increasing the molecular weight (i.e. the m/z ratio in MS) and the collision cross section of a target ion after selective complexation. This Ion Mobility orthogonal separation improves the structural elucidation. Crown ethers used as shifting agents can specifically form complexes with primary amines. The addition of crown ether to different low molecular weight fractions obtained by multidimensional LC of a water extract from Se-rich yeast permitted to detect Se isomers and confirmed their structure using IMS. [less ▲]

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See detailDevelopment of an analytical strategy to measure major selenium-containing species in juvenile turtles (Trachemys scripta scripta) by SAX-HPLC-ICP MS
Far, Johann ULg; Dyc, Christelle; Das, Krishna ULg et al

Poster (2013, July)

Sea turtles are exposed to many environmental elements such as selenium (Se). Sea turtles are listed under the Red List of threatened species by the International Union for Conservation of Nature. It is ... [more ▼]

Sea turtles are exposed to many environmental elements such as selenium (Se). Sea turtles are listed under the Red List of threatened species by the International Union for Conservation of Nature. It is thus mandatory to use low-invasive tissue collection (skin, carapace, blood ) for estimating Se exposure in these highly protected turtles. For this purpose, a biological modal Trachemys scripta scripta (or slider turtle) was selected. For two months, juvenile turtles were dietary exposed to Se by spiking the food with Selenomethionine (SeMet) or Methionine as control groups. Individuals were sacrificed after different time of exposure and tissues (skin, liver, muscle, carapace and blood) collected to perform Se speciation and determine some biological endpoints. An analytical strategy was developed to cope with the very low amount of available sample. It is briefly consisting by reduction, alkylation and proteolysis of the entire freeze-dried tissues followed by sample clean-up using ultra-filtration membrane. Then anion exchange HPLC using salt and pH gradient was developed to prevent the introduction of organic solvents, which cause severe fooling of ICP MS and avoid ultra-trace analyses of sea water in routine analysis. This method successfully achieved the detection and quantification at ppm level of expected species (i.e SeMet, selenocysteine, inorganic Se) and also unknown species but their relative amounts were time and tissues dependent. [less ▲]

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See detailDevelopment of a quantitative approach to measure phospholipids in dried drops by Raman spectroscopy
Malherbe, Cédric ULg; Jadoul, Laure ULg; Gilbert, Bernard ULg et al

Poster (2013, May 24)

Phospholipids, PL, such as the phosphatidylcholine PC(18:0/18:1), play a role in the structure of living cells and are suspected to be part of the development of some diseases, for example cancers. Mass ... [more ▼]

Phospholipids, PL, such as the phosphatidylcholine PC(18:0/18:1), play a role in the structure of living cells and are suspected to be part of the development of some diseases, for example cancers. Mass spectrometry enables the structural analysis of PL in complex biological media but imaging mass spectrometry by MALDI-MS is rather limited for quantification purposes. Complementarily, Raman spectroscopy as a non invasive and non destructive method is a potential candidate to quantify and visualise the spatial distribution of the PL by molecular imaging. Unfortunately, the lack of specific chemical function in PL, compared to others biomolecules, limits the use of Raman spectroscopy in the identification process of those PL in complex biological samples. The results presented here belong to a first study of the application of the Raman analyses on dried residues of PL and mice brain tissue performed in the lab. [less ▲]

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See detailPreliminary assessment of the risk linked to furan ingestion by babies consuming only ready-to-eat food
Scholl, Georges ULg; Humblet, Marie-France ULg; Scippo, Marie-Louise ULg et al

in Food Additives & Contaminants. Part A. Chemistry, Analysis, Control, Exposure & Risk Assessment (2013), 30(4), 654-659

The risk linked to furan ingestion has been assessed in previous papers for Belgian adults and children (Scholl et al., 2012b; Scholl et al., 2012c). The present paper focuses on infants consuming only ... [more ▼]

The risk linked to furan ingestion has been assessed in previous papers for Belgian adults and children (Scholl et al., 2012b; Scholl et al., 2012c). The present paper focuses on infants consuming only ready-to-eat baby food. As there is no Belgian baby dietary database, the furan exposure assessment was carried out by using Italian infant consumption database and Belgian contamination data. The estimated daily intake (EDI) was calculated according to a deterministic methodology. It involved 42 commercially available ready-to-eat baby food and 36 baby consumption records. The mean EDI was 1,460 ng * (kgb.w.*day)-1 which is 3.8 times higher than the 381 ng * (kgb.w.*day)-1 reported for Belgian adults, and 3.5 times higher than the 419 ng * (kgb.w. * day)-1 measured for Belgian children. To assess and characterize the risk for babies exposure the Margin of Exposure (MoE) was calculated. It highlighted that 74% of infants have a MoE below 1,000, with a minimum of 140. However, these are only preliminary results as they were calculated from a very small dataset and the infant cytochrome P450 activity is significantly different compared to the adult. Therefore, the risk linked to furan ingestion by babies should be assessed in a different manner. To this end, additional data regarding a baby diet as well as a better understanding of furan toxicity for babies are needed to characterize more accurately the risk for infants. [less ▲]

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See detailRelationships between in vitro lymphoproliferative responses and levels of contaminants in blood of free-ranging adult harbour seals (Phoca vitulina) from the North Sea
Dupont, Aurélie ULg; Siebert, Ursula; Covaci, Adrian et al

in Aquatic Toxicology (2013), 142-143

tIn vitro culture of peripheral blood leucocytes (PBLs) is currently used in toxicological studies of marinemammals. However, blood cells of wild individuals are exposed in vivo to environmental ... [more ▼]

tIn vitro culture of peripheral blood leucocytes (PBLs) is currently used in toxicological studies of marinemammals. However, blood cells of wild individuals are exposed in vivo to environmental contaminantsbefore being isolated and exposed to contaminants in vitro. The aim of this study was to highlightpotential relationships between blood contaminant levels and in vitro peripheral blood lymphocyteproliferation in free-ranging adult harbour seals (Phoca vitulina) from the North Sea. Blood samplesof 18 individuals were analyzed for trace elements (Fe, Zn, Se, Cu, Hg, Pb, Cd) and persistent organiccontaminants and metabolites ( PCBs, HO-PCBs, PBDEs, 2-MeO-BDE68 and 6-MeO-BDE47, DDXs,hexachlorobenzene, oxychlordane, trans-nonachlor, pentachlorophenol and tribromoanisole). The samesamples were used to determine the haematology profiles, cell numbers and viability, as well as thein vitro ConA-induced lymphocyte proliferation expressed as a stimulation index (SI). Correlation tests(Bravais-Pearson) and Principal Component Analysis with multiple regression revealed no statisticallysignificant relationship between the lymphocyte SI and the contaminants studied. However, the numberof lymphocytes per millilitre of whole blood appeared to be negatively correlated to pentachlorophenol(r = −0.63, p = 0.005). In adult harbour seals, the interindividual variations of in vitro lymphocyte pro-liferation did not appear to be directly linked to pollutant levels present in the blood, and it is likelythat other factors such as age, life history, or physiological parameters have an influence. In a generalmanner, experiments with in vitro immune cell cultures of wild marine mammals should be designed soas to minimize confounding factors in which case they remain a valuable tool to study pollutant effectsin vitro. [less ▲]

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See detailHigh accumulation of PCDD, PCDF, and PCB congeners in marine mammals from Brazil: a serious PCB problem
Dorneles, Paulo R; Sanz, Paloma; Eppe, Gauthier ULg et al

in Science of the Total Environment (2013), 463-464

Blubber samples from three delphinid species (false killer whale, Guiana and rough-toothed dolphin), as well as liver samples from franciscana dolphins were analyzed for dioxins and related compounds ... [more ▼]

Blubber samples from three delphinid species (false killer whale, Guiana and rough-toothed dolphin), as well as liver samples from franciscana dolphins were analyzed for dioxins and related compounds (DRCs). Samples were collected from 35 cetaceans stranded or incidentally captured in a highly industrialized and urbanized area (Southeast and Southern Brazilian regions). Dioxin-like PCBs accounted for over 83% of the total TEQ for all cetaceans. Non-ortho coplanar PCBs, for franciscanas (82%), and mono-ortho PCBs (up to 80%), for delphinids, constituted the groups of highest contribution to total TEQ. Regarding franciscana dolphins, significant negative correlations were found between total length (TL) and three variables, ΣTEQ-DRCs, ΣTEQ-PCDF and ΣTEQ non-ortho PCB. An increasing efficiency of the detoxifying activity with the growth of the animal may be a plausible explanation for these findings. This hypothesis is reinforced by the significant negative correlation found between TL and PCB126/PCB169 concentration ratio. DRC concentrations (ng/g lipids) varied from 36 to 3006, for franciscana dolphins, as well as from 356 to 30776, for delphinids. The sum of dioxin-like and indicator PCBs varied from 34662 to 279407 ng/g lipids, for Guiana dolphins from Rio de Janeiro state, which are among the highest PCB concentrations ever reported for cetaceans. The high concentrations found in our study raise concern not only on the conservation of Brazilian coastal cetaceans, but also on the possibility of human health problem due to consumption of fish from Brazilian estuaries. [less ▲]

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See detailScreening and confirmatory methods for the detection of dioxins and polychlorinated biphenyls (PCB) in foods
Focant, Jean-François ULg; Eppe, Gauthier ULg

in Rose, Martin; Fernandes, Alwyn (Eds.) Persistent organic pollutants and toxic metals in foods (2013)

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See detailLevels of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and polychlorinated biphenyls in human milk from different regions of France
Focant, Jean-François ULg; Fréry, N; Bidondo, ML et al

in Science of the Total Environment (2013), 452-453

Wereport on the pilot study carried out before the start of the Elfe project (French longitudinal study from childhood). A total of 44 samples of mature human milk were collected at home 8 weeks after ... [more ▼]

Wereport on the pilot study carried out before the start of the Elfe project (French longitudinal study from childhood). A total of 44 samples of mature human milk were collected at home 8 weeks after delivery. A total of 7 polychlorinated dibenzo-p-dioxins (PCDDs), 10 polychlorinated dibenzofurans (PCDFs), 12 dioxin-like (DL) polychlorinated biphenyls (PCBs), and 6 non dioxin-like (NDL)-PCBs were measured. For total TEQ (PCDD/Fs and DL-PCBs), the geometric mean concentration was 17.81 pg TEQWHO05/g lipids. Relative PCDD, PCDF, and DL-PCB contributions to the arithmetic mean TEQWHO05 were 38%, 18%, and 44%, respectively. The use of TEFWHO05 instead of TEFWHO98 resulted in a 27% reduction of the total TEQ value. Although PCDD levels did not significantly change (less than 0.5% increase), PCDF and DL-PCB levels both decreased by 35% and 38%, respectively. Levels have been compared to data obtained during a previous non-reported national study conducted in 1998 (TEFWHO98) in French lactaria (n = 244). The mean of PCDD/Fs has decreased about 39.4% (18.8 pg TEQWHO98/g lipids in 1998 vs 11.4 pg TEQWHO98/g lipids in pilot study), respectively 41.5% for PCDDs (10.6 pg TEQWHO98/g lipids in 1998 vs 6.2 pg TEQWHO98/g lipids in pilot study) and 36.7% for PCDFs (7.9 pg TEQWHO98/g lipids in 1998 vs 5.0 pg TEQWHO98/g lipids in pilot study). For the sum of the 6 NDL-PCBs, the 2007 geometric mean concentration in milk was 176.3 ng/g lipids. The arithmetic mean lipid concentration in 2007 breast milk was 26.4 g/l (range from 6.0 to 46.7 g/l). A PCDD/F and DL-PCB daily intake was estimated to be 62.3 pg TEQWHO05/kg body weight per day (85.0 pg TEQWHO98/kg bodyweight per day) for a baby of 5 kg of bodyweight fed daily with 700 ml of maternal milk containing 25 g/l of lipids. [less ▲]

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See detailMilk and serum standard reference materials for monitoring organic contaminants in human samples
Schantz; Eppe, Gauthier ULg; Focant, Jean-François ULg et al

in Analytical and Bioanalytical Chemistry (2013), 405

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See detailDevelopment of a quantitative approach to measure phospholipids in dried drops by Raman spectroscopy
Malherbe, Cédric ULg; Jadoul, Laure; Gilbert, Bernard ULg et al

Poster (2012, October)

We present here the results obtained during our tentative to analyse quantitatively dried drops of phospholipidic solutions by Raman spectroscopy. Drops of different solutions of phospholipid were deposed ... [more ▼]

We present here the results obtained during our tentative to analyse quantitatively dried drops of phospholipidic solutions by Raman spectroscopy. Drops of different solutions of phospholipid were deposed onto different material supports. The spots were then analyses by confocal Raman microspectroscopy. Experimental settings have been optimised and the analysis of the intensity profile of the Raman signal inside the spot allows the establishment of a calibration curve for the determination of the phospholipids amount within a 1 µL solution. [less ▲]

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See detailFuran formation upon degradation of carbohydrates in combination with proteins and lipids
Owczarek, Agnieszka; De Meulenaer, Bruno; Scholl, Georges ULg et al

Conference (2012, September 20)

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See detailFuran formation in starch-based model systems containing carbohydrates in combination with proteins, ascorbic acid and lipids
Owczarek-Fendor, Agnieszka; De Meulenaer, Bruno; Scholl, Georges ULg et al

in Food Chemistry (2012), 133(3), 816-821

Formation of the ‘‘possibly carcinogenic’’ furan during thermal treatment of a starch-based model food system containing selected sugars alone and in the presence of proteins, ascorbic acid and lipids ... [more ▼]

Formation of the ‘‘possibly carcinogenic’’ furan during thermal treatment of a starch-based model food system containing selected sugars alone and in the presence of proteins, ascorbic acid and lipids, respectively, was investigated. The results showed that in starch gels containing various sugars significantly more furan was formed at pH 6 than at pH 4. Moreover, addition of whey proteins enhanced the generation of furan considerably at both pH values tested. In acidic conditions, no significant difference was observed between the amounts of furan found in a starch–carbohydrate–ascorbic acid model system and those formed in a starch-based samples containing only ascorbic acid. Addition of fresh lipids did not affect furan formation. However, when oxidised soybean oil was applied, the generated amounts of furan were higher than expected from the sum of furan found in the separate starch–carbohydrate and starch–lipid samples. Interestingly, the most efficient carbohydrate in furan generation, among the sugars tested, at pH 6, was lactose, especially when heated in the presence of proteins. This is the first report on the generation of furan from lactose. [less ▲]

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See detailRisk assessment for furan contamination through the food chain in Belgian children
Scholl, Georges ULg; Huybrechts, Inge; Humblet, Marie-France ULg et al

in Food Additives & Contaminants (2012), 29(8), 1219-1229

Young, old, pregnant and immuno-compromised persons are of great concern for risk assessors as they represent the sub-populations most at risk. The present paper focuses on risk assessment linked to furan ... [more ▼]

Young, old, pregnant and immuno-compromised persons are of great concern for risk assessors as they represent the sub-populations most at risk. The present paper focuses on risk assessment linked to furan exposure in children. Only the Belgian population was considered because individual contamination and consumption data that are required for accurate risk assessment were available for Belgian children only. Two risk assessment approaches, so called deterministic and probabilistic, were applied and their results were compared for the estimation of the daily intake. A significant difference between the average Estimated Daily Intake (EDI) was underlined between the deterministic (419 ng * (kgb.w. * day)-1) and the probabilistic (583 ng * (kgb.w. * day)-1) approaches, which results from the mathematical treatment of the null consumption and contamination data. The risk was characterized by two ways: (1) the classical approach by comparison of the EDI to a reference dose (RfDchronic-oral) and (2) the most recent approach, namely the Margin of Exposure (MoE) approach. Both reached similar conclusions: the risk level is not of a major concern, but is neither negligible. In the first approach, only 2.7% or 6.6% (respectively in the deterministic and in the probabilistic way) of the studied population presented an EDI above the RfDchronic-oral. In the second approach, the percentage of children displaying a MoE above 10,000 and below 100 is 3% - 0% and 20% - 0.01% in the deterministic and probabilistic modes respectively. In addition, children were compared to adults and significant differences between the contamination patterns were highlighted. Whilst major contamination was linked to coffee consumption in adults (55%), no item predominantly contributed to the contamination in children. The most important were soups (19%), dairy products (17%), pasta and rice (11%), fruit and potatoes (9% each). [less ▲]

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See detailAnalytical criteria for use of MS/MS for determination of dioxins and dioxin-like PCBs in feed and food
Kotz, A; Malisch, R; Focant, Jean-François ULg et al

in Organohalogen Compounds (2012, August), 74

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See detailIdentification and quantification of concentration-dependent biomarkers in MCF-7/BOS cells exposed to 17β-estradiol by 2-D DIGE and label-free proteomics
Collodoro, Mike ULg; Lemaire, Pascale ULg; Eppe, Gauthier ULg et al

in Journal of Proteomics (2012), in press

This paper reports the identification of biomarkers resulting from the exposure of MCF-7/BOS cells to 17β-estradiol (E2). The biomarkers were identified using 2 independent and complementary techniques, 2 ... [more ▼]

This paper reports the identification of biomarkers resulting from the exposure of MCF-7/BOS cells to 17β-estradiol (E2). The biomarkers were identified using 2 independent and complementary techniques, 2-D DIGE / MALDI-TOF peptide mass fingerprint, and 2-D UPLC-ESI MS/MS. These markers form a preliminary molecular signature that can be used when testing the estrogenic activity of xenobiotics, either pure or in mixtures. [less ▲]

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See detailThe usefulness of Ion Mobility-Mass Spectrometry for Small Molecules Analysis
Far, Johann ULg; Goscinny, Séverine ULg; Joly, Laure et al

Conference (2012, March)

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See detailRisk assessment of Belgian adults for furan contamination through the food chain
Scholl, Georges ULg; Humblet, Marie-France ULg; Scippo, Marie-Louise ULg et al

in Food Additives & Contaminants (2012), 29(3), 345-353

Risk assessment is an interdisciplinary process used to quantify the risk linked to a hazard. In the present paper it is applied to quantify the risk linked to furan ingestion through the food chain for ... [more ▼]

Risk assessment is an interdisciplinary process used to quantify the risk linked to a hazard. In the present paper it is applied to quantify the risk linked to furan ingestion through the food chain for the Belgian adult population. Two approaches, deterministic and probabilistic, were carried out in parallel. The deterministic method relied on a case study, whereas the probabilistic approach involved statistical distributions of contamination and consumption data to calculate a statistical distribution of the daily intake. First, the deterministic method revealed a low estimated daily intake (EDI) for the average population (380 ng*(kgbw*day)–1) and a huge contribution of coffee consumption to the EDI (55%). Increasing or decreasing the daily coffee consumption by one cup can affect the EDI by about 22%. Afterwards, the probabilistic approach showed that the average population has a low EDI (494 ng*(kgbw*day) 1), and that high contamination levels were only registered in a small proportion of the population. Finally, a comparison of the RfDchronic oral showed that less than 10% of the Belgian population had an EDI above the reference dose proposed by the USEPA; the majority of the population had an EDI 20% below the reference dose. The margin of exposure (MoE) approach indicated that the level of risk related to furan intake through ingestion is low, with a MoE>10,000 for more than 10% of the population and no result < 100. [less ▲]

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See detailLes PCB non apparentés aux dioxines (non dioxin-like PCB) dans les denrées alimentaires et les aliments pour animaux: mise en place d'une législation européenne
Eppe, Gauthier ULg

Article for general public (2012)

La famille des PolyChloroBiphényles ou PCB regroupe un ensemble de 209 composés différents (dénommés usuellement congénères) se différenciant par le nombre (1 à 10 atomes) et la position des atomes de ... [more ▼]

La famille des PolyChloroBiphényles ou PCB regroupe un ensemble de 209 composés différents (dénommés usuellement congénères) se différenciant par le nombre (1 à 10 atomes) et la position des atomes de chlore sur la molécule biphényle. Cette famille de composés peut être divisée en deux catégories selon leurs propriétés toxicologiques, et plus particulièrement les effets tératogènes des PCB. Le premier groupe, composé de 12 congénères, se caractérise par des propriétés toxicologiques similaires aux dioxines, et il est par conséquent désigné par le terme ‘PCB de type dioxine’ (dioxin-like PCB, DL-PCB). L’autre groupe de PCB non apparenté aux dioxines (non dioxin-like PCB, NDL-PCB), présente d’autres mécanismes de toxicité pris en compte dans la gestion du risque PCB. Parmi ces 197 NDL-PCB, une sous-catégorie de six congénères relativement abondants dans l’environnement et dans les chaînes alimentaires (PCB 28, 52, 101, 138, 153 et 180), représente ce que nous appelons communément les PCB indicateurs. De par leurs propriétés de persistance, de bioaccumulation et de biomagnification, l’ensemble des PCB (DL-PCB et NDL-PCB) se retrouve fréquemment dans l’alimentation humaine et dans les aliments pour animaux. La fixation de teneurs maximales en NDL-PCB dans divers aliments fait l’objet d’une nouvelle réglementation européenne qui entrera en vigueur dès 2012. Cet article fait le point sur l’impact de ces nouvelles propositions par rapport au niveau de bruit de fond des principales classes d’aliments mais également sur l’évolution des méthodes d’analyse nécessaires pour atteindre les performances requises. [less ▲]

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