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See detailDioxin levels in fertilizers from Belgium: Determination and evaluation of the potential impact on soil contamination
Elskens, M; Pussemier, L; Dumortier, P et al

in Science of the Total Environment (2013), 454-455

Dioxins are harmful Persistent Organic Pollutants (POPs) to which humans are exposed mostly via the consumption of animal products. They can enter the food chain at any stage, including crop fertilization ... [more ▼]

Dioxins are harmful Persistent Organic Pollutants (POPs) to which humans are exposed mostly via the consumption of animal products. They can enter the food chain at any stage, including crop fertilization. Fertilizers belong to several categories: synthetic chemicals providing the essential elements (mostly N, P and K) that are required by the crops but also organic fertilizers or amendments, liming materials, etc. Ninety-seven samples of fertilizers were taken in Belgium during the year 2011 and analyzed after a soft extraction procedure for polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (DL-PCBs) using GC-IDHRMS. Only small qualitative differences could be observed between the main fertilizer categories since the PCDD:PCDF:DL-PCB average ratio obtained with the results expressed in WHO 2005-TEQ was often close to 30:30:40 (typically for sewage sludge) or 40:30:30 (typically for compost). The median dioxin levels determined were generally lower than recorded previously and were the highest for sewage sludge and compost (5.6 and 5.5 ng TEQ/kg dry weight (dw), respectively). The levels in other fertilizers were lower including manure for which the median value was only 0.2 ng TEQ/kg dw. Several fertilization scenarios relying on the use of those fertilizers were assessed taking into consideration the application conditions prevailing in Belgium. From this assessment it could be concluded that the contribution of fertilizers to the overall soil contamination will be low by comparison of other sources of contamination such as atmospheric depositions. At the field scale, intensive use of compost and sewage sludge will increase dramatically the dioxin inputs compared with other fertilization practices but this kind of immission to the soil will still be relatively low compared to the dioxin atmospheric depositions. [less ▲]

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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 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 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 detailEstimation of furan contamination across the Belgian food chain.
Scholl, Georges ULg; Scippo, Marie-Louise ULg; De Pauw, Edwin ULg et al

in Food Additives & Contaminants. Part A. Chemistry, Analysis, Control, Exposure & Risk Assessment (2012), 29(2), 172-9

This paper provides an estimate of the furan content of Belgian foods. The objective of the study was to achieve the best food chain coverage with a restricted number of samples (n = 496). The geographic ... [more ▼]

This paper provides an estimate of the furan content of Belgian foods. The objective of the study was to achieve the best food chain coverage with a restricted number of samples (n = 496). The geographic distribution, different market chains and labels, and consumption frequencies were taken into account in the construction of the sampling plan. Weighting factors such as contamination levels, consumption frequency and the diversity of food items were applied to set up the model. The very low detection capabilities (CC(beta)) of the analytical methods used (sub-ppb) allowed reporting of 78.2% of the overall dataset above CC(beta) and, in particular, 96.7% for the baby food category. The highest furan levels were found in powdered roasted bean coffee (1912 microg kg(-1)) with a mean of 756 microg kg(-1) for this category. Prepared meat, pasta and rice, breakfast cereals, soups, and baby food also showed high mean furan contents ranging from 16 to 43 microg kg(-1). Comparisons with contamination surveys carried out in other countries pointed out differences for the same food group and therefore contamination levels are related to the geographical origin of food items. [less ▲]

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See detailFuran Formation from Lipids in Starch-Based Model Systems, As Influenced by Interactions with Antioxidants and Proteins.
Owczarek-Fendor, A.; De Meulenaer, B.; Scholl, Georges ULg et al

in Journal of Agricultural and Food Chemistry (2011), 59(6), 2368-2376

The formation of furan upon sterilization of a lipid-containing starch gel was investigated in the presence of various antioxidants, namely, alpha-tocopherol, beta-carotene, and ascorbic acid, with and ... [more ▼]

The formation of furan upon sterilization of a lipid-containing starch gel was investigated in the presence of various antioxidants, namely, alpha-tocopherol, beta-carotene, and ascorbic acid, with and without proteins. Results indicated that alpha-tocopherol did not significantly influence furan formation from oxidized lipids. beta-Carotene, suggested previously to be a furan precursor itself, did influence the generation of furan in a concentration-dependent manner, although to a limited extent. Surprisingly, the presence of lipids seemed to limit the furan generation from beta-carotene. Interestingly, the addition of ascorbic acid to the emulsions containing soybean or sunflower oils considerably enhanced the formation of furan from these oils. This was also the case when fresh oils were applied, shown previously to be nearly unable to generate furan. This observation can be explained by an intensified ascorbic acid degradation stimulated by the presence of lipids. [less ▲]

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See detailFuran formation in baby food model system via lipid oxidation and sugar degradation
Owczarek-Fendor, Agnieszka; De Meulenaer, Bruno; Scholl, Georges ULg et al

in Communications in Agricultural and Applied Biological Sciences (2011), 76(1), 107-110

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See detailDioxins in Human Milk from Different Regions of France: Pilot of the French Longitudinal Study of Children (ELFE)
Vandentoren, S; Frery, N; Bidondo, ML et al

in Organohalogen Compounds (2011), 73

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See detailPLE for extraction of dioxins in animal feed and ingredients
Focant, Jean-François ULg; Scholl, Georges ULg; De Pauw, Edwin ULg et al

in Organohalogen Compounds (2010, September), 72

Within the entire complex procedure required to measure dioxins and related compounds in biological matrices, the extraction step is often seen as a well controlled step. Although maybe true for many ... [more ▼]

Within the entire complex procedure required to measure dioxins and related compounds in biological matrices, the extraction step is often seen as a well controlled step. Although maybe true for many human and food-related matrices, the situation is very different for animal feed and feed ingredients. Specific European guidelines (e.g. Commission Directive 2006/13/EC, Commission Regulation (EC) No 152/2009) exist for animal feed but only list general requirements for the various stages of the procedure. The liberty is left to laboratories to select, for example, the tools used for the extraction steps. This has the advantage to allow ‘in-house’ methods to be used, as long as they satisfy with all the requirements of the EU Regulation. In that context, it is foreseen that the European Committee for Standardization (CEN) will soon propose a standard for the determination of PCDD/Fs and PCBs in animal feed that would be the reference method to be used to solve potential issues in case of dispute over results reported from different laboratories. A major point of concern is that it has been reported earlier1 that most commonly accepted extraction procedure can conduct to significantly different results for the extraction of dioxins and related compounds in feed and feed additives such as mineral clays and various oxides. Several non-instrumental and instrumental automated approaches are available for extraction. Soxhlet extractors have long been the most used tools for non-instrumental extraction of solids. They have proven to be very efficient but some limitations encouraged the development of other approaches based on instrumental techniques. For feed extraction, pressurized liquid extraction (PLE) (also branded as accelerated solvent extraction ASE®) is the technique of choice for high sample throughput. This study reports on the investigation of the use of various solvent mixtures, extraction temperatures, and instruments (parallel PLE, sequential ASE®) for the extraction of 17 PCDD/Fs and 12 dioxin-like PCBs in mineral clay, bovine feed, fish meal, and in-house quality control animal compound feed. [less ▲]

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See detailFuran formation from vitamin C in a starch-based model system: Influence of the reaction conditions
Owczarek-Fendor, Agnieska; De Meulenaer, Bruno; Scholl, Georges ULg et al

in Food Chemistry (2010), 121(4), 1163-1170

The generation of furan from vitamin C during thermal treatment of a starch-based model system, which simulated baby food, was studied. Results indicated that the amount of sample heated in the vial ... [more ▼]

The generation of furan from vitamin C during thermal treatment of a starch-based model system, which simulated baby food, was studied. Results indicated that the amount of sample heated in the vial influenced the furan generation from ascorbic acid. Increasing the amount of heated sample from 5% to approximately 98% of the total vial volume, drastically reduced furan formation from 70 ppb to 16 ppb. Changes in ascorbic acid concentrations from 0.1 to 4.5 mg/g did not influence furan concentration nor did different ascorbic/dehydroascorbic acid molar ratios. Interestingly, waxy corn starch itself considerably enhanced furan generation from ascorbic acid. Under the same conditions, 13.2 ppb of furan was generated in starch-based samples, while in ascorbic acid buffered solutions only 0.4 ppb of furan was formed. Application of other matrices, in particular agar and hydrolysed starch, resulted in similar furan concentrations as for native starch, while in polyol solutions furan concentrations were comparable to those obtained for the buffered ascorbic acid solutions. [less ▲]

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See detailFuran formation in baby food model systems from vitamin C and unsaturated fatty acids
Owczarek-Fendor, Agnieszka; De Meulenaer, Bruno; Scholl, Georges ULg et al

Conference (2010)

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See detailImportance of fat oxidation in starch-based emulsions in the generation of the process contaminant furan.
Owczarek-Fendor, Agnieszka; De Meulenaer, Bruno; Scholl, Georges ULg et al

in Journal of Agricultural and Food Chemistry (2010), 58(17), 9579-86

The formation of the possibly carcinogenic process contaminant furan was studied in starch-based emulsions during heat treatments as applied for sterilization. Fresh and oxidized soybean, sunflower, high ... [more ▼]

The formation of the possibly carcinogenic process contaminant furan was studied in starch-based emulsions during heat treatments as applied for sterilization. Fresh and oxidized soybean, sunflower, high-oleic sunflower, olive, linseed, and rapeseed oils were compared. Results indicated that both the oil type, in particular, the fatty acid composition, and the oxidation degree of the oil determined the susceptibility of the oils to generate furan upon heating. Thus, oils containing the nutritionally relevant omega-3 unsaturated alpha-linolenic acid proved to be able to generate significant amounts of furan if the oils were oxidized. No clear relationship between p-anisidine values of various oils and the amount of generated furan could be observed. However, in the case of soybean oil, significantly more furan was produced upon an increase in oxidation degree. Surprisingly, furan formation in food-relevant systems containing fresh lipids proved to be a minor route (up to 1.5 ppb furan) compared to a previously studied vitamin C containing model system (up to 13 ppb furan). [less ▲]

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