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See detailOptimization and validation of HS-SPME-GC-MS for the determination of Furan and Alkylfurans in chocolate-based products: Impact of tempering and laser printing
Alsafra, Zouheir ULiege; Scholl, Georges ULiege; Eppe, Gauthier ULiege

in Journal of AOAC International (in press)

Objectives Two major objectives are presented. Firstly, we aim at optimizing and validating a HS-SPME-GC-MS method for the quantification of 5 alkylfurans in chocolate. Secondly, we focus our study on ... [more ▼]

Objectives Two major objectives are presented. Firstly, we aim at optimizing and validating a HS-SPME-GC-MS method for the quantification of 5 alkylfurans in chocolate. Secondly, we focus our study on measuring the quantitative impact of engraving technique on the formation of furan and its derivatives in chocolate, from the raw callets to processed end-products. Method HS-SPME-GC-MS method operating in SIM mode and using isotope dilution technique with deuterated homologue internal standards was used to quantify alkylfurans in chocolate. Results Good repeatability (RSD% = 0.1-8%, in duplicate) and intermediate precision (RSD% = 1.7-7%, n = 6) were obtained for these five process contaminants at 10, 25, and 50 µg/kg. Trueness was varying between 81 and 109%. LoQ ranged from 0.48 to 2.50 µg/kg. Relative expanded measurement uncertainties ranged from 6 to 30%. Finally, tempering is responsible for a 24% increase in furan contamination, while the laser engraving technique results in an additional 31% increase in furan. A similar trend was also observed for 2-methylfuran and 3-methylfuran, whereas no significant increases were observed for 2,3-dimethylfuran and 2,5-dimethylfuran. Conclusions and highlights A reliable and sensitive method of HS-SPME-GC-MS was reported for the first time for the analysis of furan and four alkylfurans in chocolate. This paper demonstrated that engraving using laser-based techniques can increase the levels of these compounds by up to 30%. [less ▲]

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See detailHigh pollutant exposure level of the largest European community of bottlenose dolphins in the English Channel
Zanuttini, Cyrielle; Gally, François; Scholl, Georges ULiege et al

in Scientific Reports (2019), 9

The objective of this study was to assess the levels of persistent organic pollutants (POPs) and mercury (T-Hg) in the blubber and skin, respectively, of the free-ranging bottlenose dolphins, Tursiops ... [more ▼]

The objective of this study was to assess the levels of persistent organic pollutants (POPs) and mercury (T-Hg) in the blubber and skin, respectively, of the free-ranging bottlenose dolphins, Tursiops truncatus, from the Normanno-Breton Gulf, one of the largest identified coastal population in Europe. Among all the POPs analysed in this study, the ∑NDL-PCBs were the most abundant compounds found in the blubber (mean: 1.33x105 – 0.65x105 ng.g-1 lipid weight (lw) for males and females respectively), followed by ∑DDX (1.11x104 – 4.67x103 ng.g-1 lw) > ∑DL-PCBs (8.06 x103– 2.62 x103ng.g-1 lw)> ∑PBDEs (1.95 x103– 0.64 x103ng.g-1 lw) > dieldrin (1.86 x103– 0.18 x103 ng.g-1 lw) > ∑endosulfan (405– 62 ng.g-1 lw) > HCB (86 – 52 ng.g-1 lw) > ∑HCHs (47 – 60 ng.g-1 lw) > ∑chlordane (24 – 0.97 ng.g-1 lw) > ∑PCDFs (0.3 – 0.1 ng.g-1 lw) > ∑PCDDs (0.06 – 0.05 ng.g-1 lw). The T-Hg concentrations were highly variable between individuals (2.45 x103 ng.g-1 to 21.3 x103 ng.g-1 dry weight, dw). The reported concentrations are among the highest reported for cetaceans. We strongly recommend that the Normanno-Breton Gulf be a special area of conservation (cSAC) candidate because it contains the last large European population of bottlenose dolphins (rare or threatened within a European context) designated under the EC Habitats Directive. [less ▲]

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See detailFood and Feed Control Using GCxGC-(MR)TOFMS: Dioxin measurements and beyond
Stefanuto, Pierre-Hugues ULiege; Scholl, Georges ULiege; Miklasova, Z. et al

Conference (2019, September)

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See detailAssessment of a New GC-MS/MS System for the Confirmatory Measurement of PCDD/Fs and (N)DL-PCBs in Food under EU Regulation
Franchina, Flavio ULiege; Lazzari, Eliane ULiege; Scholl, Georges ULiege et al

in Foods (2019)

Polychlorodibenzo-p-dioxins (PCDDs), polychloro-dibenzofurans (PCDFs), dioxin-like (DL), and non dioxin-like (NDL) polychlorinated biphenyls (PCBs) are currently regulated in food and feed within the ... [more ▼]

Polychlorodibenzo-p-dioxins (PCDDs), polychloro-dibenzofurans (PCDFs), dioxin-like (DL), and non dioxin-like (NDL) polychlorinated biphenyls (PCBs) are currently regulated in food and feed within the European territory (EU 2017/644-771). The confirmatory methods of analysis for checking compliance with maximum levels (MLs) for these involve either the historically-established GC-magnetic sector high-resolution mass spectrometry (GC-HRMS) and, more recently, GC-triple quadrupole mass spectrometry operating in tandem mode (GC-QQQMS/MS). In this study, the performance of a novel triple quadrupole GC-QQQMS/MS system equipped with a programable temperature vaporization (PTV) injector was evaluated for the analysis of regulated PCDD/Fs and PCBs in food and feed. The MS analyzer was equipped with a titanium ionization chamber and a new short collision cell capable to accumulate and eject ions by means of very narrow pulses that allow to minimize the noise and to adapt accumulation times for sensitive multiple reaction monitoring (MRM). The analytical capability of the system was confronted by the strict requirements (selectivity, reproducibility, linearity, quant/qual MRM transitions, accuracy, robustness) set by the EU Regulation for a range of standards, quality control (QC) and food/feed samples. In this respect, the approach showed high precision (1.9–15% relative standard deviation (RSD) at low pg/µL) and accuracy (>80%, except for one hexa-CDD). The quantitative results were also compared to the most used GC-HRMS. In this case, comparable results in terms of single congener concentration basis and total toxic equivalent (TEQ) basis for PCDD/Fs and DL-PCBs were obtained for the QC samples analyzed. [less ▲]

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See detailEffect of Different Parameters on Composition of Volatile Components of Leaf, Stem and Seed from Algerian Bupleurum fruticosum L. Extracted by Hydrodistillation and Headspace Solid-Phase Microextraction
Mékaoui, Radja; Benkaci-Ali, Farid; Scholl, Georges ULiege et al

in Journal of Essential Oil-Bearing Plants (2019), 22(1), 50-72

The present study describes the effect of physical parameters of plant and fiber coating on the qualitative and quantitative volatile profile of Bupleurum fruticosum L., (leave, stem and seed) from Yama ... [more ▼]

The present study describes the effect of physical parameters of plant and fiber coating on the qualitative and quantitative volatile profile of Bupleurum fruticosum L., (leave, stem and seed) from Yama Gouraya Algerian Park using the headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC/MS). The HS-SPME-GC/MS analysis showed a significant variation of the volatile composition according some parameters as the type of fiber coating polydimethyl siloxane (PDMS) and polydimethyl siloxane/divinylbenzene (PDMS-DVB), particle size (dp), and the mass (m) used. Results demonstrated that HS-SPME recoveries are strongly conditioned by the polarity and volatility of analytes were investigated, and by the composition and physical state of the vegetable matrix, characteristics which, in their turn, condition the headspace composition. According to the particle size and mass used, there were significant differences in chemical classes composition of monoterpenes (leaves: 28.35-62.01 %, stems: 23.8-57.49 % and seeds: 60.92-85.76 %) and sesquiterpene hydrocarbons (leaves: 19.39-36.91 %, stems: 36.71-59.90 % and seeds: 7.9-21.96 %) as well as oxygenated compounds (leaves: 6.17-50.3 %, stems: 4.22-9.12 % and seeds 4.17-9.43 %). Whereas hydrodistillation (heating based) essential oil showed a different qualitative and quantitative aromatic profile compared to the green technique HS-SPME (adsorption and affinity based), in chemical groups as monoterpene (leaves: 59.8, stems: 69.37 and seeds: 88.14 %) and sesquiterpenes (leaves: 13.93, stems: 17.17 and seeds: 4.23 %) hydrocarbons as well as in oxygenated compounds (leaves: 24.32, stems: 21.19 and seeds: 5.37 %). [less ▲]

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See detailInvestigating decadal changes in persistent organic pollutants in Scottish grey seal pups
Robinson, K. J.; Hall, A. J.; Scholl, Georges ULiege et al

in Aquatic Conservation (2019), 29(S1), 86-100

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See detailGC×GC-(MR)TOFMS in Food and Feed Control: Going Beyond Dioxin Measurements
Stefanuto, Pierre-Hugues ULiege; Scholl, Georges ULiege; Miklasova, Z et al

Scientific conference (2018, December)

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See detailDetermination of PCDD/Fs and dl-PCBs in ash and particle samples generated by an incineration plant for hospital and industrial waste in Northern of Algeria
Kerchich, Yacine; Moussaoui, Yacine; Scholl, Georges ULiege et al

in Atmospheric Pollution Research Journal (2018), (9), 968-975

PCDD/Fs and dl-PCB in ash and flue gas emission samples, generated by an incineration plant of clinical and industrial waste, were investigated at the sole incineration waste plant currently operating in ... [more ▼]

PCDD/Fs and dl-PCB in ash and flue gas emission samples, generated by an incineration plant of clinical and industrial waste, were investigated at the sole incineration waste plant currently operating in Northern Algeria. We studied the incineration of six types of waste including bank notes, CD-ROM, clinical waste, sludge inks, expired pharmaceuticals and tobacco. For each of them, we collected gaseous emissions and ashes after incineration. Final extracts of the different wastes were analyzed by high-resolution gas chromatography coupled to high-resolution mass spectrometry (HRGC–HRMS). Flue gas results indicated that the emission concentrations of PCDD/Fs, expressed in I-TEQs, were in the range of 22.78 – 1647.86 pg I-TEQ Nm-3, while for dl-PCB in flue gas, expressed in WHO-TEQs, levels reported were between 0.66 – 46.97 pg WHO-TEQ Nm-3. Regarding incinerator ashes, levels span from 1.68 to 879.56 pg I-TEQ g-1 for PCDD/Fs and 0.1 to 28.30 pg WHO-TEQ g-1 for dl-PCBs. The contribution of dl-PCBs to the sum TEQ was relatively low for all matrices analyzed. A positive and consistent correlation was obtained between the 2,3,4,7,8-PeCDF concentration and I-TEQ PCDD/Fs values in flue gas and ash samples. XRF method was used to determine the major inorganic compounds that could be responsible of the inhibition of PCDD/Fs formation. [less ▲]

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See detailFood and feed control using GC×GC-(MR)TOFMS: Dioxin measurements and beyond
Stefanuto, Pierre-Hugues ULiege; Scholl, Georges ULiege; Miklasova, Z et al

in Organohalogen Compounds (2018)

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See detailEffect of different parameters on composition of volatile components of Myristica fragrans seeds extracted by hydrodistillation assisted by microwave and head-space solid-phase microextraction
Bouchachia, C; Benkaci-Ali, F; Eppe, Gauthier ULiege et al

in Journal of Essential Oil Research (2017), volume 29(issue 6),

Hydrodistillation assisted by microwave (HDAM) and Head space solid phase micro-extraction (HSSPME) of Myristica fragrans houtt (MF) were investigated. A kinetic study was performed for MF seeds using two ... [more ▼]

Hydrodistillation assisted by microwave (HDAM) and Head space solid phase micro-extraction (HSSPME) of Myristica fragrans houtt (MF) were investigated. A kinetic study was performed for MF seeds using two techniques (HDAM: Hydrodistillation assisted by microwave and SDAM: steam distillation assisted by microwave). The effect of the cryogenic grinding (CG) showed differences in yields and composition of volatile oils compared to the simple grinding (SG). HDAM–SG (3.4%) and SDAM–SG (2.55%) allowed extraction of substantial amounts of volatile oils in less time compared with HDAM–CG (4.75%) and SDAM–CG (3.8%). The kinetic study (differential and accumulated yields) of essential oil extraction was quantitatively and qualitatively performed showing a significant variation of composition with the extraction time, especially for accumulated yields such as sabinene (31.48–38.78%), α-pinene (12.74–14.09%) and β-pinene (10.01–12.11%). Similarly, the HS-SPME–GC–MS analysis showed also a significant variation of MF seeds volatile composition according some parameters as the type of fibre coating (PDMS: Polydimethylsiloxane and PDMS– DVB: Polydimethylsiloxane divenylbenzene), particle size, grinding mode and the mass used. The chemical groups (monoterpenoids, aliphatic and aromatic alcohols and esters) showed specific behaviour in SPME analysis. SPME sampling parameters were optimized for these components. [less ▲]

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See detailSpatial variation in the accumulation of POPs and mercury in bottlenose dolphins of the Lower Florida Keys and the coastal Everglades (South Florida)
Damseaux, France ULiege; Kiszka, J.; Heithaus, M.R. et al

in Environmental Pollution (2017), 220

The bottlenose dolphin (Tursiops truncatus) is an upper trophic level predator and the most common cetacean species found in nearshore waters of southern Florida, including the Lower Florida Keys (LFK ... [more ▼]

The bottlenose dolphin (Tursiops truncatus) is an upper trophic level predator and the most common cetacean species found in nearshore waters of southern Florida, including the Lower Florida Keys (LFK) and the Florida Coastal Everglades (FCE). The objective of this study was to assess contamination levels of total mercury (T-Hg) in skin and persistent organic pollutants (PCBs, PBDEs, DDXs, HCHs, HCB, Σ PCDD/Fs and Σ DL-PCBs) in blubber samples of bottlenose dolphins from LFK (n = 27) and FCE (n = 24). PCBs were the major class of compounds found in bottlenose dolphin blubber and were higher in individuals from LFK (Σ 6 PCBs LFK males: 13421 ± 7730 ng.g-1 lipids, Σ 6 PCBs LFK females: 9683 ± 19007 ng.g-1 lipids) than from FCE (Σ 6 PCBs FCE males: 5638 ng.g-1 ± 3627 lipids, Σ 6 PCBs FCE females: 1427 ± 908 ng.g-1 lipids). These levels were lower than previously published data from the southeastern USA. The Σ DL-PCBs were the most prevalent pollutants of dioxin and dioxin like compounds (Σ DL-PCBs LFK: 739 ng.g-1 lipids, Σ DL-PCBs FCE: 183 ng.g-1 lipids) since PCDD/F concentrations were low for both locations (mean 0.1 ng.g-1 lipids for LFK and FCE dolphins). The toxicity equivalences of PCDD/Fs and DL-PCBs expressed as TEQ in LFK and FCE dolphins is mainly expressed by DL-PCBs (81% LFK - 65% FCE). T-Hg concentrations in skin were significantly higher in FCE (FCE median 9314 ng.g-1 dw) compared to LFK dolphins (LFK median 2941 ng.g-1 dw). These bottlenose dolphins concentrations are the highest recorded in the southeastern USA, and may be explained, at least partially, by the biogeochemistry of the Everglades and mangrove sedimentary habitats that create favourable conditions for the retention of mercury and make it available at high concentrations for aquatic predators. [less ▲]

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See detailEffect of the Extraction Technique, Heating Time and Cryogenic Grinding (N2 at -196°C) on the Composition of Cumin Seeds Volatile Oil
Mékaoui, R; Benkaci-Ali, Farid; Scholl, Georges ULiege et al

in Journal of Essential Oil-Bearing Plants (2016), 19(8), 1903-1919

Two techniques of extraction of essential oils (Steam distillation assisted by microwave (SDAM) and hydrodistillation assisted by microwave (HDAM)) are respectively advanced steam distillation (SD) and ... [more ▼]

Two techniques of extraction of essential oils (Steam distillation assisted by microwave (SDAM) and hydrodistillation assisted by microwave (HDAM)) are respectively advanced steam distillation (SD) and hydrodistillation techniques (HD), in which a microwave oven is used in the extraction process. They are considered as accelerated techniques extraction performed at atmospheric pressure. The cryogrinding (CG) showed a difference on the yields and aromatic profile comparing to the sample grinding. Isolation and concentration of volatile compounds are performed by a single stage for the extraction of volatile oil from Algerian (Sahara) Cuminum cyminum seeds (CCS). The chemical composition of the essential oil of this plant as a function of extraction time was also studied. The major components and family classes showed a significant variation with the extraction time. Gas chromatography (GC), GCxGC-mass spectrometry (GCxGC-MS)] were utilised for qualitative and quantitative analysis of essential oils extracted by these two methods. The major compounds are cumin aldehyde (HDAM-CG: 20.50-53.35 %, SDAM-CG: 21.68 66.6 %), p-cymene (HDAM-CG: 14.1-37.54 %, SDAM-CG: 6.06-20.18 %), β-pinene (HDAM-CG: 4.53-14.74 %, SDAM-CG: 4.3-32.65 %) and γ-terpinene (HDAM-CG: 1.26-14.70 %, SDAM-CG: 5.13-18.23 %). [less ▲]

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See detailThe performance of atmospheric pressure gas chromatography–tandem mass spectrometry compared to gas chromatography–high resolution mass spectrometry for the analysis of polychlorinated dioxins and PCBs in food and feed samples
ten Dam, Guillaume; Pussente, Igor; Scholl, Georges ULiege et al

in Journal of Chromatography. A (2016), 1477

Recently, gas chromatography tandem mass spectrometry (GC–MS/MS) has been added in EuropeanUnion (EU) legislation as an alternative to magnetic sector high resolution mass spectrometry (HRMS) for the ... [more ▼]

Recently, gas chromatography tandem mass spectrometry (GC–MS/MS) has been added in EuropeanUnion (EU) legislation as an alternative to magnetic sector high resolution mass spectrometry (HRMS) for the analysis of dioxins and dioxin like polychlorinated biphenyls (dl-PCB) in food and feed. In this study the performance of APGC–MS/MS compared to GC–HRMS is investigated and compared with EU legislation. The study includes the legislative parameters, relative intermediate precision standard devia-tion (SRw,rel), trueness, sensitivity, linear range and ion ratio tolerance. In addition, over 200 real samplesof large variety and spanning several orders of magnitude in concentration were analyzed by both techniques and the selectivity was evaluated by comparing chromatograms. The SRw,rel and trueness were evaluated using (in-house) reference samples and fulfill to EU legislation, though the SRw,rel was better with GC–HRMS. The sensitivity was considerably better than of GC–HRMS while the linear range was similar. Ion ratios were mostly within the tolerable range of ±15%. A (temporary unresolved) systematic deviation in ion ratio was observed for several congeners, yet this did not lead to exceeding of the maxi-mum ion ratio limits. The APGC–MS/MS results for the non-dioxin-like-PCBs (ndl-PCBs) were negatively biased, particularly for PCB138 and 153 in contaminated samples. The selectivity of APGC–MS/MS was lower for several matrices. Particularly for contaminated samples, interfering peaks were observed in the APGC chromatograms of the native compounds (dioxins) and labeled internal standards (PCBs). These can lead to biased results and ultimately to false positive samples. It was concluded that the determination of dioxins and PCBs using APGC–MS/MS meets the requirements set by the European Commission. However, due to generally better selectivity and SRw,rel, GC–HRMS is the preferred method for monitoring purposes. [less ▲]

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See detailDevelopment and optimization of a TD-GC/MS methodology for detection and quantification of furan released in air using of an experimental design.
Alsafra, Zouheir ULiege; Scholl, Georges ULiege; Romain, Anne-Claude ULiege et al

Poster (2016, July 07)

In the aim of understanding the way in which human is exposed to furan present in the air of an occupational area, an analytical method of Thermal desorption-gas chromatography/Mass spectrometry (TD-GC/MS ... [more ▼]

In the aim of understanding the way in which human is exposed to furan present in the air of an occupational area, an analytical method of Thermal desorption-gas chromatography/Mass spectrometry (TD-GC/MS) has been developed and optimized using a Plackett–Burman experimental design. This method was then used to study the phenomena of diffusion of furan released in air from a contamination source. This source of furan is simply a coffee machine located in a closed controlled room. Results show that furan concentration increases quickly over time after turning on the coffee machine until reaching a maxima. Then it starts to decrease slowly. On the other hand, concentration of furan seems to be identical everywhere in the conditioned room in each moment. [less ▲]

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