Determination of chloramphenicol in honey, 1 shrimp and poultry meat with liquid chromatography-mass spectrometry. Validation of the method according to Commission Decision 2002/657/EC

in Food Analytical Methods (in press)

Chloramphenicol (CAP) is an antibiotic used for the treatment of bacterial infections in human and veterinary medicine. The use of CAP was prohibited in the European Union in 1994. Control laboratories ... [more ▼]

Chloramphenicol (CAP) is an antibiotic used for the treatment of bacterial infections in human and veterinary medicine. The use of CAP was prohibited in the European Union in 1994. Control laboratories are required to use suitably validated analytical methods to check sample compliance with the regulation. A quantitative method based on liquid chromatography coupled to isotopic dilution tandem mass spectrometry (LC–IDMS/MS) was developed for the determination of chloramphenicol in honey, shrimp and poultry meat. The experimental protocol consisted of a liquid-liquid extraction with ethyl acetate. Separation and detection were realized respectively by a 2690 Waters HPLC (Milford, MA, USA) and a Micromass Triple Quadrupole mass spectrometer (Micromass, Manchester, UK), equipped with an Electrospray source. The effects of mobile phase additives on the response of LC/ESI/MS were examined. Two different HPLC columns were tested: the X-Terra from Waters and the Alltima HP C18 HL from Alltech (Deerfield, IL, USA). A validation of the method was conducted according to the EU criteria for the analysis of chloramphenicol in foods. The decision limits (CCα) were 0.04, 0.03, 0.07 µg kg-1 and the detection capabilities (CCβ) were 0.05, 0.04, 0.08 µg kg-1 for honey, shrimp and poultry meat respectively. Those values are below the minimum required performance limit (MRPL) set at 0.3 µg kg-1 by the EU and 0.1 µg kg-1 by Belgium. Our protocol has the advantage to propose a unique extraction method working as well for honey, shrimp and poultry meat, contrary to similar published methods in which a different extraction method is used for each type of matrix. [less ▲]

Preliminary assessment of the risk linked to furan ingestion by babies consuming only ready-to-eat food

in Food Additives & Contaminants. Part A. Chemistry, Analysis, Control, Exposure & Risk Assessment (2013)

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 ▲]

A review of dietary and non-dietary exposure to bisphenol-A.

in Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association (2012), 50(10), 3725-40

Due to the large number of applications of bisphenol-A (BPA), the human exposure routes are multiple. We aimed to review shortly the food and non-food sources of BPA, and to evaluate their contribution to ... [more ▼]

Due to the large number of applications of bisphenol-A (BPA), the human exposure routes are multiple. We aimed to review shortly the food and non-food sources of BPA, and to evaluate their contribution to the human exposure. Food sources discussed here include epoxy resins, polycarbonate and other applications, such as paperboard and polyvinylchloride materials. Among the non-food sources, exposures through dust, thermal paper, dental materials, and medical devices were summarized. Based on the available data for these exposure sources, it was concluded that the exposure to BPA from non-food sources is generally lower than that from exposure from food by at least one order of magnitude for most studied subgroups. The use of urinary concentrations from biomonitoring studies was evaluated and the back-calculation of BPA intake seems reliable for the overall exposure assessment. In general, the total exposure to BPA is several orders of magnitude lower than the current tolerable daily intake of 50 mug/kg bw/day. Finally, the paper concludes with some critical remarks and recommendations on future human exposure studies to BPA. [less ▲]

Quantification of Acrylamide in Various Belgian Potato Products Using Solid Phase Extraction and Liquid Chromatography Tandem Mass Spectrometry Detection

in Food and Public Health (2012), 2(5), 137-141

Acrylamide (CH2=CHCONH2), a neurotoxic and potentially carcinogenic substance for human health, is in the glare of the spotlights for a few years. This is mostly due to the fact that acrylamide was found ... [more ▼]

Acrylamide (CH2=CHCONH2), a neurotoxic and potentially carcinogenic substance for human health, is in the glare of the spotlights for a few years. This is mostly due to the fact that acrylamide was found worldwide in various heated foodstuffs. Levels reported in the literature vary from 25 to 2000 ìg/kg and potato products are considered as the most contaminated. A possible pathway of synthesis of acrylamide is the Maillard reaction between reducing sugars and the amino acid asparagine. The aim of this study was to develop a liquid chromatography/mass spectrometry method to analyse as quickly as possible acrylamide in a variety of Belgian food samples such as potatoes, French fries, crisp bread, coffee, corn-flakes, etc. The sample preparation consisted in a liquid/liquid extraction, a centrifugation, followed by purification with Solid Phase Extraction (SPE). The instruments used were a Waters 2690 Alliance HPLC system coupled to a Micro-mass Quattro Ultima Platinum triple-quadrupole mass spectrometer. The analysis was performed in MS/MS mode using isotopic dilution technique for quantification. An internal 13C3 labelled standard was added prior to extraction. Quantifica-tion in MS/MS mode was calculated by reconstructing the ion current with the most abundant daughter ions for native and 13C labelled standard (ions of m/z 55 and 58). [less ▲]

Furan formation in starch-based model systems containing carbohydrates in combination with proteins, ascorbic acid and lipids

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 ▲]

Risk assessment of Belgian adults for furan contamination through the food chain

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 ▲]

Estimation of furan contamination across the Belgian food chain.

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 ▲]

Screening, post-screening and confirmation analysis of antibiotics in pork and chicken meat marketed in Vietnam.

in EuroResidue VII: conference on residues of veterinary drugs in food (2012)

Analyse sensorielle et biochimique du Tilapia du Nil (Oreochromis niloticus) conservé à température ambiante (30°C) et à 4°C

Poster (2012)

Selection and characterization of PCB-binding DNA aptamers.

in Analytical Chemistry (2012), 84(3), 1669-76

Polychlorinated biphenyls (PCBs) are persistent organic pollutants (POPs) that resist natural degradation and bioaccumulate in nature. Combined with their toxicity, this leads them to cause cancer and ... [more ▼]

Polychlorinated biphenyls (PCBs) are persistent organic pollutants (POPs) that resist natural degradation and bioaccumulate in nature. Combined with their toxicity, this leads them to cause cancer and other health hazards. Thus, there is a vital need for rapid and sensitive methods to detect PCB residues in food and in the environment. In this study, PCB-binding DNA aptamers were developed using PCB72 and PCB106 as targets for aptamer selection. Aptamers are synthetic DNA recognition elements which form unique conformations that enable them to bind specifically to their targets. Using in vitro selection techniques and fluorometry, an aptamer that binds with nanomolar affinity to both the PCBs has been developed. It displayed high selectivity to the original target congeners and limited affinity toward other PCB congeners (105, 118, 153, and 169), suggesting general specificity for the basic PCB skeleton with varying affinities for different congeners. This aptamer provides a basis for constructing an affordable, sensitive, and high-throughput assay for the detection of PCBs in food and environmental samples and offers a promising alternative to existing methods of PCB quantitation. This study therefore advances aptamer technology by targeting one of the highly sought-after POPs, for the first time ever recorded. [less ▲]