Polycyclic aromatic hydrocarbons (PAHs) in meat products and estimated PAH intake by children and the general population in Estonia

The concentrations of benzo[a]pyrene and 11 other polycyclic aromatic hydrocarbons (PAHs) were analysed from 322 commercial, cured meat products and 14 home-grilled meat samples as part of the Estonian food safety monitoring programme during 2001-2005. The maximum acceptable concentration of 5 µg kg^-1 for benzo[a]pyrene was exceeded in 3.4% of samples. The highest PAH concentrations were detected in home-grilled pork samples. Using of disposable grilling unit resulted in 1.6 times higher PAH concentrations compared to the traditional wood-burning grill. The average intake of benzo[a]pyrene and sum of 12 PAHs from meat products was estimated for children (age 1-16 years) on the basis of an individual food consumption questionnaire and, for the general population, based on national food consumption data. The highest total PAH concentrations detected were 16 µg kg^-1 in smoked meat and ham, 19 µg kg^-1 in smoked sausage and 6.5 µg kg^-1 in smoked chicken samples. Since smoking and grilling are prevalent meat-cooking methods in Estonia, the impact of meat products is assessed to be significant in overall PAH intake.     

Comparison of various assays used for detection of beta-lactam antibiotics in poultry meat

In this study, microbiological tests for the detection of beta-lactam antibiotics in meat and meat products were evaluated. The traditional FPT (four plate test, containing Bacillus subtilis and Kocuria rhizophila), BsDA (Bacillus stearothermophilus disc assay) and a newly developed microbiological test, Premi®Test (containing Bacillus stearothermophilus) were included in the study. The limit of detection (LOD) of the Premi®Test was compared with the LOD of the traditional methods. The detection limits of the tests were determined by using beta-lactam antibiotic standards dissolved in meat juice, as well as meat tissue obtained from laying hens after experimental administration of amoxicillin. Positive samples, based on inhibition of growth of the organism in the test, were confirmed by high performance liquid chromatography (HPLC). Growth inhibition in the traditional tests is visible as a clear zone on the plate, whereas for Premi®Test, this is based on the absence of a colour change of the test. The LODs of antibiotics tested were as follows: Penicillin G (PENG) 5 µg kg^-1, amoxicillin (AMOX) 10 µg kg^-1, ampicillin (AMP) 25 µg kg^-1, oxacillin (OXA) 30 µg kg^-1, and cloxacillin (CLOX) 30 µg kg^-1 on the plate with Bacillus stearothermophilus. Beta-lactam antibiotics can be detected also on one plate seeded with Kocuria rhizophila, although the LODs are higher: PENG 10 µg kg^-1, AMOX 25 µg kg^-1, AMP 30 µg kg^-1, OXA 50 µg kg^-1, and CLOX 50 µg kg^-1. Premi®Test was performed according to the Standard Operating Procedure intended for detection of beta-lactam antibiotics in poultry tissues with following LODs: PENG 4 µg kg^-1, AMOX 5 µg kg^-1, AMP 5 µg kg^-1, OXA 40 µg kg^-1, CLOX 50 µg kg^-1. All tests are able to detect beta-lactam antibiotics such as penicillin G, ampicillin, amoxicillin, oxacillin and cloxacillin below the maximum residue level (MRL). However, the detection limits of the Premi®Test for PENG, AMOX and AMP were below the limits of BsDA and the plate containing Kocuria rhizophila.     

Cadmium and mercury in cephalopod molluscs: Estimated weekly intake

Cadmium and mercury concentrations were measured in the flesh and hepatopancreas of different species of cephalopod molluscs (European squid, common octopus, curled octopus, horned octopus, pink cuttlefish, common cuttlefish) in order to establish whether the concentrations exceeded the maximum levels fixed by the European Commission. In hepatopancreas, the levels of cadmium were substantially higher than those in flesh (flesh 0.11-0.87 µg g^-1 wet weight, hepatopancreas 2.16-9.39 µg g^-1 wet weight), whilst the levels of mercury (flesh 0.13-0.55 µg g^-1 wet weight, hepatopancreas 0.23-0.79 µg g^-1) were approximately double those in flesh. Concentrations exceeding the maximum permitted limit of cadmium were found in 39.8 and 41.0% of common octopus and pink cuttlefish flesh, respectively. For mercury, concentrations above the limit were found only in octopuses, and precisely in 36.8, 50.0 and 20.0% of flesh samples of common, curled and horned octopus, respectively. In the hepatopancreas, concentrations of cadmium and mercury were above the proposed limits in all the samples examined. The estimated weekly intake of between 0.09 and 0.49 µg kg^-1 body weight for cadmium and between 0.05 and 0.24 µg kg^-1 body weight for mercury made only a small contribution to the provisional tolerable weekly intake (cadmium 1.3-7.0%, mercury 1.0-4.8%) set by the WHO.     

Aflatoxin and ochratoxin A content of spices in Hungary

In October and November 2004, 91 spice samples (70 ground red pepper, six black pepper, five white pepper, five spice mix and five chilli samples), the majority of which originated from commercial outlets, were analysed for aflatoxins B₁, B₂, G₁ and G₂ (AFB1, AFB2, AFG1, AFG2) and ochratoxin A (OTA) content by high-performance liquid chromatography (HPLC) after immunoaffinity column clean-up. Eighteen of the 70 ground red pepper samples contained AFB1, seven of them in a concentration exceeding the 'maximum level' of 5 µg kg^-1 (range 6.1-15.7 µg kg^-1). Of the other spices assayed, the AFB1 contamination of one chilli sample exceeded 5 µg kg^-1 (8.1 µg kg^-1). Thirty-two of the 70 ground red pepper samples contained OTA, eight of them in a concentration exceeding the 10 µg kg^-1 'maximum level' (range 10.6-66.2 µg kg^-1). One chilli sample was contaminated with OTA at 2.1 µg kg^-1. The AFB1 and OTA contamination of ground red pepper exceeding the 'maximum level' (5 and 10 µg kg^-1, respectively) was obviously the consequence of mixing imported ground red pepper batches heavily contaminated with AFB1 and OTA with red pepper produced in Hungary. This case calls attention to the importance of consistently screening imported batches of ground red pepper for aflatoxin and ochratoxin A content and strictly prohibiting the use of batches containing mycotoxin concentrations exceeding the maximum permitted level.     

Five-year survey of ochratoxin A in processed sultanas from Turkey

The results of surveillance for ochratoxin A (OTA) in 1885 samples of sultanas taken during five crop years between 1999 and 2003 are reported. The analytical method was based on extraction with methanol + sodium bicarbonate and clean-up by immunoaffinity column chromatography followed by high-performance liquid chromatography with fluorescence detection. The limit of detection for OTA was 0.3 µg kg^-1. The results show that 9.3% of the samples contained no detectable levels of OTA, whereas 0.6% had concentrations exceeding 10 µg kg^-1; the remaining 90.3% had levels within the range 0.3-10 µg kg^-1. The overall mean OTA concentration in the total number of 1885 samples taken was 1.36 ± 2.91 µg kg^-1; the overall median was calculated as 0.90 µg kg^-1.     

Methylmercury determination in fish and seafood products and estimated daily intake for the Spanish population

The mercury content of 25 samples of fish and seafood products most frequently consumed in Spain was determined. A simple method comprising cold vapour and atomic absorption spectrometry was used to determine separately inorganic and organic mercury. In all samples inorganic mercury content was below 50 µg kg^-1. There was wide variability, among not only the mercury levels of different fish species, but also for different samples of the same species — with the methylmercury content ranging from below 54 to 662 µg kg^-1. The highest mean methylmercury content was found in fresh tuna. Based on an average total fish consumption of 363 g/person week^-1, the methylmercury intake was estimated to be 46.2 µg/person week^-1. Therefore, the mercury intake of Spanish people with a body weight ≤ 60 kg is lower than the Joint FAO/WHO Expert Committee on Food Additives (JECFA) provisional tolerable weekly intake (PTWI) of 1.6 µg kg^-1 body weight, but exceeds the US National Research Council (NRC) limit of 0.7 µg kg^-1 body weight week^-1 based on a benchmark dose.     

The occurrence of nitrofuran metabolites in the tissues of chickens exposed to very low dietary concentrations of the nitrofurans

The global problem of food products contaminated by residues of the banned carcinogenic nitrofuran drugs has prompted research into how such residues accumulate in tissues. In the study described here, two aspects have been investigated where the nitrofurans accumulate in tissues from chickens exposed to either a dietary or an environmental source of contamination. Twenty groups of broilers were fed a diet containing one of the nitrofurans: furazolidone, nitrofurazone, nitrofurantoin or furaltadone at concentrations of 30, 100, 300, 1000 and 3000 µg kg^-1. At the lowest concentration of furazolidone contamination (0.01% of the therapeutic dose) tissue bound AOZ metabolite residues were detected in liver (1.1 ± 0.2 µg kg^-1) and in muscle (0.33 ± 0.03 µg kg^-1). Similar results were obtained for AMOZ (0.6 ± 0.2 µg kg^-1 in liver), the tissue bound metabolite of furaltadone. There was no appreciable accumulation of nitrofurantoin in chicken muscle. The AHD metabolite was not detected in muscle from birds fed nitrofurantoin at either 30 or 100 µg kg^-1. For nitrofurazone the concentrations of the SEM metabolite were higher in muscle than in liver for all dietary concentrations. The potential for a contaminated environment to cause nitrofuran residues in chickens was investigated. Six chickens were placed in a pen that was previously occupied by birds fed a diet containing 3000 µg kg^-1 of furazolidone. After 24 hours' exposure of the chickens to the litter in the pen, AOZ residues of 0.13 ± 0.04 and 0.10 ± 0.03 µg kg^-1 were detected in liver and muscle, respectively. The results of both experiments have implications for the poultry industry in trying to eliminate nitrofurans from their production systems, and for regulatory analysts faced with the detection of low concentrations of the drugs, both in tissues and in feedingstuffs.     

Determination of selected mycotoxins in mould cheeses with liquid chromatography coupled to tandem with mass spectrometry

A simple and feasible method is described for analysing nine mycotoxins in cheese matrix. The method involves liquid extraction followed by high performance liquid chromatographic separation and mass spectrometric detection of the analytes, and allows the determination of aflatoxins B1, B2, G1, G2 and M1, ochratoxin A, mycophenolic acid, penicillic acid and roquefortine C simultaneously. Average recoveries of the mycotoxins from spiked samples at concentration levels of 5-200 µg kg^-1 ranged from 96-143%. Within-day relative standard deviations at these concentration levels varied from 2.3-12.1%. The limit of quantification for aflatoxin M1 was 0.6 µg kg^-1 and for the other compounds 5 µg kg^-1. The method developed was applied for analysing these mycotoxins in blue and white mould cheeses purchased from Finnish supermarkets. Roquefortine C was detected in all of the blue mould cheese samples in concentrations of 0.8-12 mg kg^-1. One blue cheese contained also 0.3 mg kg^-1 mycophenolic acid. The other investigated mycotoxins were absent in the samples.     

Australian survey of acrylamide in carbohydrate-based foods

A method was developed and validated for the determination of acrylamide in carbohydrate-based foods. Solid-phase extraction employing a mixed-bed anion and cation exchange cartridge in series with a C18 extraction disk was used to clean-up water extracts of food samples before analysis by liquid chromatography coupled with tandem mass spectrometry detection. The limit of detection was calculated as approximately 25 μg kg^-1 and the limit of reporting was 50 μg kg^-1. The average method recovery for 84 samples from a range of matrices reporting was 99% with a relative standard deviation of 11.2%. A survey was conducted of 112 samples of carbohydrate-based foods composited from 547 products available in the Australian market. The analytical results were used in conjunction with Australian food consumption data derived from the 1995 National Nutrition Survey (NNS) to prepare preliminary dietary exposure estimates of Australians to acrylamide through only the food groups examined. Mean dietary exposure to acrylamide resulting from consumption of the foods tested, for Australians aged 2 years and above, was estimated as 22-29 µg day^-1 (equivalent to 0.4-0.5 µg kg^-1 bodyweight day^-1) and between 73 and 80 µg day^-1 (1.4 and 1.5 µg kg^-1 bodyweight day^-1) for 95th percentile consumers. Young children (2-6 years) consuming acrylamide-containing foods had a higher acrylamide exposure on a per kilogram bodyweight basis (mean 1.0-1.3 µg kg^-1 bodyweight day^-1). The estimated exposure of Australians to acrylamide is similar to that estimated for other countries.     

Annual variation of deoxynivalenol in Danish wheat flour 1998-2003 and estimated daily intake by the Danish population

The occurrence of deoxynivalenol (DON) in Danish wheat flour was studied during the period 1998-2003 by either capillary gas chromatography with electron capture detection and liquid chromatography coupled to an ion trap mass spectrophotometer. A total of 151 samples were collected from mills and the retail market in Denmark. Contamination levels varied considerably from year-to-year with the highest concentrations occurring in samples from the 2002 harvest with mean and median concentrations of 255 and 300 µg kg^-1, respectively. Compared to other harvest years, 2002 had the highest amount of precipitation around flowering time, i.e. from the end of June to the beginning of July covering weeks 25-27. The lowest average levels were found in samples from the 2001 harvest, where weeks 25-27 were dry compared with other harvest years. The highest value (705 µg kg^-1) was obtained in a flour sample from the 2002 harvest, but none of the tested samples exceeded the maximum limit of 750 µg kg^-1, which has been recently introduced by the European Commission for DON in flour used as raw materials in food products. Calculation of chronic or usual intake by a deterministic approach showed that intake did not exceed the TDI of 1 µg kg^-1 bw day^-1 either for the whole population or for children. A probabilistic approach also showed that intake in general was below the TDI, but intake for children in the 99% percentile amounted to more than 75% of the TDI. The highest intake is calculated to be 2.5 µg kg^-1 bw day^-1.     

Acrylamide in Asian foods in Hong Kong

About 400 food samples, mainly Asian foods available in Hong Kong, were tested for acrylamide by an LC-MS/MS method using [1, 2, 3-¹³C₃]-acrylamide as surrogate. The acrylamide levels in the more commonly consumed food items in the food groups such as rice and rice products, noodles, bakery and batter-based products, were generally less than 60 μg kg^-1. Higher levels were found in the food groups such as biscuit-related products and crisps. The highest levels were detected in potato crisps (1500-1700 μg kg^-1). Lower levels were found in rye flour-based crisps (440 μg kg^-1), followed by corn-based (65 to 230 μg kg^-1) and wheat flour-based crisps (61-200 μg kg^-1), and then rice flour-based crisps (15-42 μg kg^-1). The acrylamide formation during deep frying of a wheat flour-based product, Chinese fried fritter, was studied. Deep-frying at 170°C resulted in gentle but steady rise in acrylamide content. A steep rise for frying at 210°C was recorded. The moisture content of the product decreased with frying time, but the fat content increased. It is proposed that the reaction for the formation of acrylamide was initiated on the surface and then penetrated into the interior of the food matrix by heat transfer via radiation/conduction and diffusion of hot oil.     

Consumers' ability to discriminate aflatoxin-contaminated Brazil nuts

The objectives of the study were to investigate the extent to which consumers can separate nuts with a high content of aflatoxin from sound nuts, and whether sorting results can be improved by information or whether they are affected by certain factors. A test panel consisting of 100 subjects was asked to crack 300 g Brazil nuts and to sort the nuts into those they considered edible and inedible. The test showed that consumers can, on current behaviour, discriminate aflatoxin-contaminated Brazil nuts to a significant extent. The median and the 95th percentile of the total concentrations of aflatoxins (B₁, B₂, G₁, G₂) in the samples before sorting were 1.4 and 557 µg kg^-1, respectively, and in the edible fractions after sorting 0.4 and 56 µg kg^-1, respectively. Given that levels of aflatoxins before sorting exceed either 2 µg aflatoxin B₁ kg^-1 or totally 4 µg aflatoxins kg^-1, there was no effect of aflatoxin concentrations before sorting on the probability of exceeding these thresholds in the edible fraction. This means that similar sorting results were obtained for samples with aflatoxin levels exceeding either of the two thresholds, irrespective of if the thresholds were exceeded with a few µg kg^-1 or up to more than 1000 µg kg^-1. None of the tested factors (such as sex, age, level of education, ethnic background or knowledge of mycotoxins) had any effects on the probability of exceeding either of the two aflatoxin thresholds.     

FTIR-ATR infrared spectroscopy for the detection of ochratoxin A in dried vine fruit

A method of screening sultanas for ochratoxin A (OTA) contamination, using mid-infrared spectroscopy/Golden Gate single-reflection ATR (attenuated total reflection), is described. The main spectral characteristics of sultanas from different sources were identified in a preliminary acquisition and spectral analysis study. Principal component analysis (PCA) showed that samples of various origins had different spectral characteristics, especially in water content and the fingerprint region. A lack of reproducibility was observed in the spectra acquired on different days. However, spectral repeatability was greatly improved when water activity of the sample was set at 0.62. A calibration curve of OTA was constructed in the range 10-40 µg OTA kg^-1. Samples with OTA levels higher than 20 µg kg^-1 were separated from samples contaminated with a lower concentration (10 µg OTA kg^-1) and from uncontaminated samples. The reported methodology is a reliable and simple technique for screening dried vine fruit for OTA.     

Justifying the need to prescribe limits for toxic metal contaminants in food-grade silver foils

The use of silver foils in various food preparations is a common practice in Middle Eastern and South East Asian countries. The FAO/WHO Joint Expert Committee on Food Additives (JECFA) has included silver in the list of food additives, but specifications were not prepared. Indian food legislation has included food-grade silver foil and laid down a purity requirement of 99.9%. This leaves an unspecified margin of 0.1% or 1000 µg g^-1 for contaminants. Therefore, a study to investigate the levels of metallic contaminants in food-grade silver foil was undertaken. Of 178 foils analysed, 161 (90%) contained silver, whilst 10% were fraudulently made up of aluminium. In the case of silver foils, 46% of the samples adhered to the desired purity requirement of 99.9%, while 54% had a lower silver content. Copper was present in 86.3% of the silver foils, while chromium, nickel and lead contamination was found in over 54% of samples. Cadmium levels were detected in 28% of the silver foils and manganese was present in 6.8% of samples. In silver foils showing metal contaminants, average levels were found for nickel (487 µg g^-1), lead (301 µg g^-1), copper (324 µg g^-1), chromium (83 µg g^-1), cadmium (97 µg g^-1) and manganese (43 µg g^-1), which being appreciable justify the need to prescribe limits for some metals in food-grade silver foil as well as for silver powder used in confectioneries and medicinal preparations. The work reported here should encourage manufacturers to use high-purity raw materials and take suitable precautions to reduce unwarranted exposure of consumers to toxic metal contaminants.     

A sulfadimidine model to evaluate pharmacokinetics and residues at various concentrations in laying hen

Low level intake of drugs from the ingestion of contaminated feed may lead to residue problems in food animals. Sulfadimidine (SDD) was used as a model to determine the residue risk at various doses in laying hens. The drug was administered as a single intravenous injection (100 mg kg^-1 body weight, BW), as a single oral dose (100, 30, 10, 3, 1 mg kg^-1 BW) and via medicated feed for 7 consecutive days (30, 10, 3 mg kg^-1 BW). Drug levels were determined with HPLC-UV for plasma, yolk and albumen. Pharmacokinetic values, which were calculated using a first-order one-compartment model, residue levels and transfer rates into the eggs were found to be dose-dependent. Even low doses of 3 and 1 mg kg^-1 BW resulted in measurable residues in yolk and albumen 1 day after a single oral administration. After ingestion of medicated feed at 3 mg kg^-1 BW, mean drug levels at 0.14 ± 0.01 µg g^-1 were found in albumen and at 0.09 ± 0.01 µg ml^-1 in plasma. Generally, the residue levels in albumen and plasma were higher than in yolk. These findings demonstrate a residue risk for the consumer even after low level intake of drugs.     

Determination of acrylamide in coffee and chocolate by pressurised fluid extraction and liquid chromatography-tandem mass spectrometry

A selective and sensitive procedure has been developed and validated for the determination of acrylamide in difficult matrices, such as coffee and chocolate. The proposed method includes pressurised fluid extraction (PFE) with acetonitrile, florisil® clean-up purification inside the PFE extraction cell and detection by liquid chromatography (LC) coupled to atmospheric pressure ionisation in positive mode tandem mass spectrometry (APCI-MS-MS). Comparison of ionisation sources (atmospheric pressure chemical ionisation (APCI), atmospheric pressure photoionization (APPI) and the combined APCI/APPI) and clean-up procedures were carried out to improve the analytical signal. The main parameters affecting the performance of the different ionisation sources were previously optimised using statistical design of experiments (DOE). PFE parameters were also optimised by DOE. For quantitation, an isotope dilution approach was used. The limit of quantification (LOQ) of the method was 1 µg kg^-1 for coffee and 0.6 µg kg^-1 for chocolate. Recoveries ranged between 81-105% in coffee and 87-102% in chocolate. The accuracy was evaluated using a coffee reference test material FAPAS T3008. Using the optimised method, 20 coffee and 15 chocolate samples collected from Valencian (Spain) supermarkets, were investigated for acrylamide, yielding median levels of 146 µg kg^-1 in coffee and 102 µg kg^-1 in chocolate.     

Fumonisin B1, fumonisin B2, zearalenone and ochratoxin A contamination of maize in Croatia

Mycotoxins are products of moulds that frequently contaminate maize. In this study the presence of mycotoxins fumonisin B₁ (FB₁), fumonisin B₂ (FB₂), zearalenone (ZEA) and ochratoxin A (OTA) was determined in 49 maize grain samples collected in autumn 2002. The most frequent finding was that of FB₁(100%), followed by ZEA (84%) and OTA (39%), while FB₂ was found only in three samples. The co-occurrence of two and three mycotoxins was found in 55 and 37% of samples, respectively. The concentrations (mean ± SD) of FB₁, ZEA and OTA in positive samples were 459.8 ± 310.7, 3.84 ± 6.68 and 1.47 ± 0.38 µg kg^-1, respectively, and the concentrations of FB₂ in three positive samples were 68.4, 109.2 and 3084.0 µg kg^-1. Although such low concentrations of mycotoxins are not a significant source of exposure in countries with a European diet, a few samples with extreme values indicate that thorough control is needed.     

Survey of ochratoxin A and deoxynivalenol in stored grains from the 1999 harvest in the UK

Three hundred and twenty samples from the 1999 UK harvest comprising wheat (201 samples), barley (106) and oats (13) were analysed for ochratoxin A and deoxynivalenol. A small number of organic samples was also obtained. Samples were collected from farms, central stores, mills, maltings and ports from across the UK from February to April 2000. Ochratoxin A and deoxynivalenol analysis was by affinity column clean up and high-performance liquid chromatography with fluorescence and ultraviolet light detection, respectively, with limits of detection of 0.2 and 20 μg kg^-1. The survey found ochratoxin A at below 5 μg kg^-1 in 97% of the samples indicating satisfactory storage conditions. The remaining 3% of the samples contained ochratoxin A at levels between 5.2 and 231 μg kg^-1, but none of these samples was intended for human consumption. Deoxynivalenol was detected in 88% of all samples, with 83% below 100 μg kg^-1; the maximum level was 600 μg kg^-1. Twenty samples containing deoxynivalenol at or above 150 μg kg^-1 by high-performance liquid chromatography were all confirmed by gas chromatography/mass spectrometry. Nivalenol was also detected by gas chromatography/mass spectrometry at levels of 50 μg kg^-1 or higher in 18 of 20 samples where deoxynivalenol was confirmed.     

Intake of ochratoxin A and deoxynivalenol through beer consumption in Belgium

Estimations of ochratoxin A (OTA) and 4-deoxynivalenol (DON) exposure of the Belgian population through beer consumption were made using the results of the recent Belgian food survey and the compiled data set of OTA and DON levels in conventionally and organically produced beers in 2003-05. For the consumers of organic beers, the daily intake of OTA was 0.86 (in 2003), 1.76 (in 2004) and 0.72 (in 2005) ng kg^-1 body weight (bw), considering the mean beer consumption (0.638 litres) and the average level of OTA in 2003, 2004 and 2005, respectively. Using the 97.5th percentile of beer consumption (1.972 litres), the corresponding OTA daily intakes were 2.65, 5.44 and 2.24 ng kg^-1 bw, which are close or above the tolerable daily intake (TDI) of 5 ng kg^-1 bw. For the consumers of conventional beers, the OTA intakes were low: 0.23, 0.23 and 0.11 ng kg^-1 bw day^-1 for the average beer consumption, in 2003, 2004 and 2005 against 0.72, 0.73 and 0.34 ng kg^-1 bw day^-1 when the 97.5th percentile level was considered. As for the DON intake, the estimates were quite low for both conventional and organic beer consumers when the provisional maximum TDI (PMTDI) of 1 µg kg^-1 bw was considered. Average consumption of organic beer led to daily intakes of 0.05 and 0.04 µg DON kg^-1 bw in 2003 and 2004, respectively, whilst for conventional beer, daily intakes were 0.07 and 0.05 µg DON kg^-1 bw. At the 97.5th percentile level of beer consumption, daily intakes of 0.15 and 0.13 µg kg^-1 bw were obtained for organic beers against 0.23 and 0.17 µg kg^-1 bw for conventional ones. The results showed that beer could be an important contributor to OTA exposure in Belgium, even though a declining trend seems to be apparent during the last year of monitoring. Therefore, efforts should be devoted to maintain the OTA levels as low as reasonably achievable, especially for organic beer.     

Determination of 3-chloropropane-1,2-diol as its 1,3-dioxolane derivative at the μg kg-1 level: Application to a wide range of foods

This paper reports the application of a GC/MS method for the quantification of 3-chloropropane-1,2-diol (3-MCPD) at low µg kg^-1 levels through the determination of its 1,3-dioxolane derivative to a wide range of foodstuffs. The proposed protocol is based on the methods generally performed in control laboratories. The two main stages of the method — the solid-phase extraction and the purification of the derivatives — have been optimized. The within-laboratory reproducibility meets the official performance criteria for verifying 3-MCPD at the 20 µg kg^-1 limit stipulated by the European Community for soy sauce. The limit of quantification was below 5 µg kg^-1 for all the foodstuffs analysed. This method offers a valuable alternative to the draft CEN European Standard: instead of diethyl ether, much safer ethyl acetate is used; derivatization is more selective; and reagents are common stable chemicals. This method was successfully applied to toasted bread, savoury crackers, cheese, soups, including vegetable-based soups, meat products such as salami, vegetable oils, sauces, soy sauce and related products. Upon checking the method performance in the case of vegetable oils, the unexpected presence of monobromopropanediols was detected.