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1.
Levels of benzo[a]pyrene (BaP) and benzo[a]anthracene (BaA) in “Provola” cheese samples from Calabria, smoked naturally and using commercial smoke-flavouring, have been determined. A comparative study of BaP and BaA concentrations was carried out on rind, exterior zone, core and slice of these samples. Quantitative determination of BaP and BaA was ascertained by HPLC using fluorescence detection. Levels of BaP and BaA were found in all smoked “Provola” cheese samples, but higher in cheese smoked with natural methods (0.46–1.13 µg kg?1 for BaP and 1.38–9.29 µg kg?1 for BaA) compared to samples smoked using commercial flavouring (0.085–0.32 µg kg?1 for BaP and 1.20–2.98 µg kg?1 for BaA). The smoking process contributes to polycyclic aromatic hydrocarbons contamination; however, for improved food safety, the use of commercial buffered smoke is preferable to traditional smoking procedures.  相似文献   

2.
In Mexico, maize tortillas are consumed on a daily basis, leading to possible aflatoxin exposure. In a survey of 396 2-kg samples, taken over four sampling days in 2006 and 2007 from tortilla shops and supermarkets in Mexico City, aflatoxin levels were quantified by HPLC. In Mexico, the regulatory limit is 12?µg?kg?1 total aflatoxins for maize tortillas. In this survey, 17% of tortillas contained aflatoxins at levels of 3–385?µg?kg?1 or values below the limit of quantification (<LOQ) and, of these, 13% were >12?µg?kg?1 and 87% were below the regulatory limit. Average aflatoxin concentrations in 56 contaminated samples were: AFB1 (12.1?µg?kg?1); AFB2 (2.7?µg?kg?1); AFG1 (64.1?µg?kg?1) and AFG2 (3.7?µg?kg?1), and total AF (20.3?µg?kg?1).  相似文献   

3.
An indirect competitive enzyme-linked immunosorbent assay (ELISA) method using a monoclonal antibody for deoxynivalenol (DON) detection in wheat and flour was standardised and validated (detection limit?=?177.1?µg?kg?1) and its performance was compared with LC-MS, quantification limit?=140?µg?kg?1). DON recovery ranged from 88.7% to 122.6% for wheat grain and from 70.6% to 139.3% for flour. Among the 38 wheat samples evaluated, DON was detected in 29 samples (76.3%) by ic-ELISA (281.6–12?291.4?µg?kg?1) and in 22 samples (57.9%) by LC-MS (155.3–9906.9?µg?kg?1). The 0.93 correlation coefficient between ic-ELISA and LC-MS data in 19 positive DON wheat samples demonstrated the reliability and efficiency of ic-ELISA. Results indicated that standardised ic-ELISA was suitable for DON screening in wheat samples and the need for continuous monitoring of mycotoxin levels in foodstuffs.  相似文献   

4.
To evaluate the potential public health risk of ethyl carbamate (EC), EC exposure from fermented foods and beverages for Hong Kong population was estimated. In 276 samples analysed, EC was detected (limit of detection (LOD) at 0.4?µg?kg?1) in 202 samples (73%), with higher levels in fermented red bean curd (150–650?µg?kg?1) and yellow wine (140–390?µg?kg?1), while low or non-detected (ND) in preserved vegetables (ND–10?µg?kg?1) and fermented tea (ND–15?µg?kg?1). The estimated dietary exposure from all fermented foods and beverages was 8.27?ng?kg?1?bw?day?1, while exposure excluding alcoholic beverages was 5.42?ng?kg?1?bw?day?1, with calculated margins of exposure (MOEs) at 3.6?×?104 and 5.5?×?104 respectively. The risk of adverse health effects was low for the average population but higher (MOE?of?103) for high consumers of alcoholic beverages especially habitual drinkers of alcoholic types with high EC contents.  相似文献   

5.
Acrylamide (AAm) is a carcinogenic chemical that can form in thermally processed foods by the Maillard reaction of glucose with asparagine. AAm can easily be formed especially in frequently consumed chips and cereal-based foods depending on processing conditions. Considering these properties of AAm, a new, simple and green method is proposed for the extraction of AAm from thermally processed food samples. In this study, an ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate, [Bmim][BF4]) as extractant was used in the presence of a cationic phenazine group dye, 3,7-diamino-5-phenylphenazinium chloride (PSH+, phenosafranine) at pH 7.5 for the extraction of AAm as an ion-pair complex from selected samples. Under optimum conditions, the analytical features obtained for the proposed method were as follows; linear working range, the limits of detection (LOD, 3Sb/m) and quantification (LOQ, 10Sb/m), preconcentration factor, sensitivity enhancement factor, sample volume and recovery% were 2.2–350 µg kg?1, 0.7 µg kg?1, 2.3 µg kg?1, 120, 95, 60 mL and 94.1–102.7%, respectively. The validity of the method was tested by analysis of two certified reference materials (CRMs) and intra-day and inter-day precision studies. Finally, the method was successfully applied to the determination of AAm levels in thermally processed foods using the standard addition method.  相似文献   

6.
Medicinal herbs have a very important role in health protection and disease control, and have been used in health foods. Polycyclic aromatic hydrocarbons (PAHs) have carcinogenic, biological and mutagenic effects. In this paper, the content of 16?PAHs as representative contaminants in nine Chinese medicinal herbs, as additives for health foods, was investigated in order to ensure food safety from this source. A highly sensitive isotope dilution-gas chromatography-tandem mass spectrometry (ID-GC-MS/MS) method combined with gel permeation chromatography (GPC) and solid-phase extraction (SPE) was developed. Calibration curves showed good linearity for all PAHs (R 2?>?0.999), and the limit of quantification (LOQ) ranged from 0.42 to 2.7?µg?kg?1. Average recoveries for these compounds were in the range of 52.5–117%, 52.6–119% and 81.4–108% at the concentrations of 10, 50 and 250?µg?kg?1 with RSD of 1.8–15%, 0.9–15% and 1.0–15%, respectively. The proposed method was used for the analysis of nine Chinese medicinal herbs. Total levels of PAHs varied from 98.2?µg?kg?1 (cassia seed) to 2245?µg?kg?1 (eucommia bark). The highest level was found for phenanthrene (Phe) in liquorice root (631.3?µg?kg?1), indigowoad leaf (551.0?µg?kg?1), rose flower (435.2?µg?kg?1) and eucommia bark (432.3?µg?kg?1). The proposed method could provide a useful basis for safety monitoring of herbs and risk management for PAHs in the health food industry.  相似文献   

7.
Resins based on melamine-formaldehyde and related analogues such as methylolated melamine are used to cross-link coatings used inside food cans and on the metal closures of glass jars. Thirteen commercially coated cans and closures representing 80% of the European market were tested using simulants under realistic industrial heat-processing conditions for canned and jarred foods. The food simulants and the retort conditions used were 3% acetic acid for 1?h at 100°C and 10% ethanol for 1?h at 130°C. The highest migration level seen for melamine into simulant was 332?µg?kg?1. There was no detectable migration of the melamine analogues cyanuric acid (<1?µg?kg?1) or ammelide (<5?µg?kg?1) from any sample. Twelve of the thirteen samples released no detectable ammeline (<5?µg?kg?1) but the coating giving the highest release of melamine did also release ammeline at 8?µg?kg?1 with the higher of the two process temperatures used. Migration experiments into food simulant and foods themselves were then conducted using two experimental coatings made using amino-based cross-linking resins. Coated metal panels were exposed to the food simulant 10% (v/v) aqueous ethanol and to three foodstuffs under a range of time and temperature conditions both in the laboratory and in a commercial food canning facility using proprietary time and temperature conditions. The highest migration into a food was 152?µg?kg?1 from the first coating processed for a long time at a moderate sterilisation temperature. The highest migration into simulant was also from this coating at 220?µg?kg?1 when processed at 134°C for 60?min, dropping to 190?µg?kg?1 when processed at 123°C for 70?min. Migration from the second coating was quite uniformly two to three times lower under all tests. These migration results were significantly higher than the levels of melamine extractable using 95% ethanol at room temperature. The experiments show that commercial canning and retorting can be mimicked in an acceptable way using laboratory tests with an autoclave or a simple pressure cooker. The results overall show there is hydrolytic degradation of the melamine cross-linked resins to release additional melamine. There is a strong influence of the temperature of heat treatment applied with foods or simulants but only a minor influence of time of heating and only a minor influence, if any, of food/simulant acidity.  相似文献   

8.
Type-B trichothecenes (deoxynivalenol (DON), nivalenol (NIV), fusarenone-X (FUS-X), 15-acetyldeoxynivalenol (15ADON), and 3-acetyldeoxynivalenol (3ADON)) were determined in 338 cereal-based products. Detection limit, quantification limit and mean recovery for five toxins were in the ranges 0.7–2.6?µg?kg?1, 2.1–7.8?µg?kg?1 and 73–110%, respectively. The range of occurrence and average level in samples were, respectively, 21–88% and 5.2–121.8?µg?kg?1 for NIV, 10–96% and 1.7–109.5?µg?kg?1 for DON, 2–39% and 0.4–3.6?µg?kg?1 for FUS-X, 0–80% and 0–17.3?µg?kg?1 for 15ADON, and 0–29% and 0–1.5?µg?kg?1 for 3ADON. Regarding co-occurrence, 64% of samples had more than two type-B trichothecenes. The estimated daily intakes of NIV, DON, FUS-X, 15ADON, and 3ADON were 0.077, 0.048, 0.004, 0.006 and 0.002?µg?kg?1?bw?day?1, respectively. These results suggest that current exposure levels do not indicate the possibility of adverse effects, but consideration of the combined exposure of type-B trichothecenes may be required due to the high frequency of co-occurrence.  相似文献   

9.
Methylmercury intake for adult males of twelve provinces in China was estimated by means of the 2007 Chinese Total Diet Study. Methylmercury levels were measured in twelve food groups of each province of four regions and was only found in the aquatic food groups. The range for methylmercury contents of aquatic foods was 3.29–31.60?µg?kg?1, being 50–87% of total mercury. Methylmercury intakes from aquatic foods for adult males of twelve provinces ranged from 0.003 to 0.138?µg?kg?1?bw?week?1 with average of 0.041?µg?kg?1?bw?week?1, which were estimated according to methylmercury contents and corresponding aquatic food consumption. Methylmercury intakes for the Chinese population were far below the corresponding provisional tolerable weekly intake (PTWI), which was established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). Consequently, there was little health risk from methylmercury exposure for the average Chinese population.  相似文献   

10.
The aim of this study was to quantify polycyclic aromatic hydrocarbon (PAH) levels in milk powder samples commercialised in Argentina and Brazil during 2012. Thirty-one samples were available from the retail market. An HPLC method for the determination of PAHs was applied involving a clean-up step with silica cartridges. Recoveries were greater than 79% for all PAHs analysed. Reproducible determination with adequate detection and quantification limits (LOD and LOQ) were attained by HPLC with fluorescence detection for 14 PAHs. Acenaphthylene was determined with a UV–VIS detector. There is no significant difference in any PAHs or in the sum of them between the Argentinean and Brazilian samples. Therefore, the samples were evaluated together. The highest concentration of benzo(a)pyrene (BaP) detected was 0.57 µg kg?1 in milk powder. Contamination of samples expressed as the sum of 15 analysed PAHs varied between 11.8 and 78.4 µg kg?1 and as PAH4 (BaP, chrysene, benzo(a)anthracene and benzo(b)fluoranthene) was between 0.02 and 10.16 µg kg?1. The correlation coefficient for PAH2 (BaP and chrysene) and PAH4 groups was 0.95, for PAH2 and PAH8 it was 0.71, and for PAH4 and PAH8 it was 0.83. All the samples were below the regulatory limit for BaP, but 65% of commercial milk powders do not comply with the European Union limit for PAH4. This is the first report of PAH contamination in powder milk from Argentina and Brazil.  相似文献   

11.
Concentrations of polycyclic aromatic hydrocarbons (PAHs) were determined in 115 samples of olive oil (extra virgin olive oil, virgin olive oil, olive oil, pomace olive oil and blended olive oil), cooking oil (corn oil, sunflower oil, sesame oil, palm olein oil, soya oil, canola oil, mustard oil, peanut oil and mixed vegetable oil) and fat (butter and table margarine) collected from retail stores in Kuwait. Carcinogenic benzo[a]pyrene (BaP) was detected in 43% of the samples analyzed. Benz[a]anthracene and chrysene were detected in 37 and 45% of the samples, respectively, that did not contain BaP. Of the individual non-carcinogenic PAHs, naphthalene showed the highest mean concentration (14 µg kg?1), while for the carcinogenic PAHs, BaP (0.92 µg kg?1) and chrysene (0.87 µg kg?1) showed the highest mean values. Approximately 20% of the samples within the olive oil and cooking oil sub-categories exceeded the EU maximum tolerable limit for BaP, with the highest level of 6.77 and 11.1 µg kg?1, respectively. For the fat sub-category, 9% of the samples exceeded the tolerance limit, with the highest level of 3.67 µg kg?1. The Kuwaiti general population's dietary exposure to the genotoxic PAHs (PAH8: benz[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene, dibenz[a,h]anthracene and benzo[ghi]perylene) was estimated to be 196 ng day?1 (3.3 ng kg?1 bw day?1, assuming an average adult body weight of 60 kg). Results indicated that PAH8 and BaPeq (total sum benzo[a]pyrene equivalents) are more reliable measures of the concentrations of other carcinogenic PAHs in oil and fat samples, while BaP and PAHs alone are not good indicators of the occurrence or degree of contamination by carcinogenic PAHs in these food products.  相似文献   

12.
Milk thistle (MT) dietary supplements are widely consumed due to their possible liver-health-promoting properties. As botanicals they can be contaminated with a variety of fungi and their secondary metabolites, mycotoxins. The aflatoxigenic fungus Aspergillus flavus has been previously isolated from these commodities. Currently, there is no published method for determining aflatoxins (AFs) in MT. Therefore, a liquid chromatography (LC) method validated for aflatoxin analysis in botanicals was evaluated and applied to MT. The method consisted of acetonitrile/water extraction, immunoaffinity column clean-up, LC separation, post-column photochemical reaction derivatisation and fluorescence detection. The average recoveries for AFs added to MT seeds, herb, oil-based liquid extract and alcohol-based liquid extract were 76% or higher. The mean relative standard deviation was <10%. The limit of detection (LOD) was 0.01?µg kg?1 and the limit of quantification (LOQ) was 0.03?µg kg–1. The method was used to conduct a small survey. A total of 83 MT samples from the US market were analysed. AFs were detected in 19% of the samples with levels ranging from 0.04 to 2.0?µg kg–1. Additionally, an aflatoxigenic A. flavus strain from ATTC and an A. parasiticus strain isolated from MT herb powder were found to produce high amounts of aflatoxins (11,200 and 49,100?µg kg–1, respectively) when cultured in MT seed powder. This is the first study reporting on aflatoxin contamination of MT botanical supplements and identifying methodology for AF analysis of these commodities.  相似文献   

13.
Hazelnut samples of different origin were collected in stores in Northern Italy and analysed for aflatoxin (AF) contamination by a sensitive chromatographic method on the basis of a tandem mass spectrometer with electrospray ionisation. The effects of two extracting solvent mixtures (methanol/water and acetonitrile/water) and different extraction times were tested and compared in terms of recovery. Analysis showed that 35 out of 93 samples (37.6%) were contaminated by AFs. The incidence of positive samples was higher in Turkish (66.7%) than in Italian samples (35.9%). Mean AF contamination was higher (p?=?0.045, Kruskal–Wallis test) in the Turkish samples (0.33?µg?kg–1) compared to the Italian (0.14?µg?kg–1) ones. In both cases, however, a low level of total AF contamination was found in the positive samples (0.64?µg?kg–1), both being far below the maximum limit set in European legislation.  相似文献   

14.
An efficient LC method was developed for screening the presence of quinolones (QLs) – comprising fluoroquinolones (FQs) and acidic quinolones (AQs) – residues in various livestock and fishery products. Targeted analytes were for nine FQs of marbofloxacin (MAR), ofloxacin (OFL), norfloxacin (NOR), ciprofloxacin (CIP), enrofloxacin (ENR), danofloxacin (DAN), orbifloxacin (ORB), difloxacin (DIF) and sarafloxacin (SAR), and three AQs of oxolinic acid (OXA), nalidixic acid (NAL) and flumequine (FMQ). Samples comprised ten different food products covering five matrices: muscle (cattle, swine and chicken), liver (chicken), raw fish (shrimp and salmon), egg (chicken), and processed food (ham, sausage and fish sausage). This method involved a simple extraction with (1:1) acetonitrile–methanol, a highly selective clean-up with an immobilised metal chelate affinity column charged with Fe3+, a fast isocratic LC analysis using a short column (20?mm?×?4.6?mm, 3?µm) with a mobile phase of (15:85:0.1) methanol/water/formic acid, and fluorescence detection (excitation/emission wavelengths of 295?nm/455?nm for FQs (495?nm for MAR), and 320?nm/365?nm for AQs). Among FQs, pairs of NOR/OFL, ORB/DIF and ENR/DAN were incompletely resolved. A confirmatory LC run with a Mg2+ containing methanolic mobile phase was also proposed for the samples suspected of being positive. The optimised method gave satisfactory recoveries of 88.5% (56.1–108.6%) and 78.7% (44.1–99.5%) for intra- and inter-day assays with relative standard deviations of 7.2% (0.7–18.4%) and 6.8% (1.4–16.6%), respectively. Limits of quantitation ranged from 0.8?µg?kg?1 (DAN) to 6.5?µg?kg?1 (SAR). This method was successfully employed to analyse 113 real samples and two positive samples were found: fish sausage (CIP 990?µg?kg?1) and shrimp (ENR 20?µg?kg?1).  相似文献   

15.
A simple, rapid and cost-effective method has been established for the determination of the quantity of benzo(a)pyrene (BaP), one of the most carcinogenic polycyclic aromatic hydrocarbons (PAHs), in roasted, smoked and charcoal grilled foods. Second-derivative constant-energy synchronous fluorescence spectrometry (DCESFS) improves the spectral resolution and selectivity of the fluorescence method. By using this method, processed meat, fish and some other food samples were analysed without resorting to complex pre-separation and purification procedures. The method was found to have a recovery of 97.7% ± 4.3%. The limit of detection (LOD) for BaP was 0.14 μg kg?1, far below the regulatory limit (1.0 μg kg?1) for BaP in food samples specified by the European Union. A certified reference material (Coconut oil, BCR?-458) was used to confirm the validity of the proposed method. The results suggest that the measurements are in a good agreement with the certified BaP concentrations (5.4% deviation). The results obtained by the proposed method for analysing BaP in food samples correlated well with those obtained by GC/MS.  相似文献   

16.
Selected commercial processed foods available in the Brazilian market (306 samples) were analysed for furan content using a validated gas chromatography-mass spectrometry method preceded by headspace solid phase micro-extraction (HS-SPME-GC/MS). Canned and jarred foods, including vegetable, meat, fruit and sweet products, showed levels up to 32.8?µg?kg?1, with the highest concentrations observed in vegetables and meats. For coffee, furan content ranged from 253.0 to 5021.4?µg?kg?1 in the roasted ground coffee and from not detected to 156.6?µg?kg?1 in the beverage. For sauces, levels up to 138.1?µg?kg?1 were found. In cereal-based products, the highest concentrations (up to 191.3?µg?kg?1) were observed in breakfast cereal (corn flakes), cracker (cream crackers) and biscuit (wafer). In general, these results are comparable with those reported in other countries and will be useful for a preliminary estimate of the furan dietary intake in Brazil.  相似文献   

17.
A total of 214 samples, consisting of brown rice, barley, mixed grains, corn, wheat and wheat flour were analysed for T-2 and HT-2 toxins using high-performance liquid chromatography with fluorescence detection. Recovery and repeatability were 79.9%–107.5% and 4.9%–14.5% for T-2, and 74.0%–106.1% and 5.0%–17.9% for HT-2, respectively. T-2 toxin was detected in 11 (5.1%) of all samples. The highest incidence was found in corn (21.7%) followed by mixed grains and brown rice. Mean of all samples was 1.5–4.1?µg?kg?1, the maximum level being 41.5?µg?kg?1 in corn. HT-2 toxin was detected in 126 (58.9%) of all samples, and the mean values were 26.4–59.2?µg?kg?1. The estimated daily intakes for the sum of T-2 and HT-2 toxins were 2.56, 3.22, 2.53, 0.03, 0.01 and 2.45?ng (kg?bw)?1?day?1 in brown rice, barley, mixed grains, corn, wheat and wheat flour, respectively.  相似文献   

18.
ABSTRACT

Acrylamide, a colourless and odourless crystalline solid, formed via the Maillard reaction in food, has been reported with harmful properties for humans, such as toxicity and carcinogenicity. Three hundred and four processed food samples from 17 product types, collected in Hanoi, Vietnam, were analyzed by LC-MS/MS to measure the acrylamide concentration. The limit of detection (LOD) and the limit of quantification (LOQ) of acrylamide were 1 µg Kg?1 and 3 µg Kg?1, respectively. Effectively, the highest acrylamide content is usually found in processed food, which is one of the primary reasons of increased acrylamide content in food. All French fried samples contained acrylamide above 500 µg kg?1. Acrylamide concentration in non-fried noodle, vermicelli, rice noodle, ph?, dried vegetable, and rice cracker is lower than in potato chips, fried potatoes, fried cake, and fried noodles. The results could be helpful to estimate exposure and risk assessment of acrylamide in Vietnam.  相似文献   

19.
A novel GC–MS method was developed for the determination of acrylamide, which is applicable to a variety of processed foods, including potato snacks, corn snacks, biscuits, instant noodles, coffee, soy sauces and miso (fermented soy bean paste). The method involves the derivatization of acrylamide with xanthydrol instead of a bromine compound. Isotopically labelled acrylamide (d 3-acrylamide) was used as the internal standard. The aqueous extract from samples was purified using Sep-Pak? C18 and Sep-Pak? AC-2 columns. For amino acid-rich samples, such as miso or soy sauce, an Extrelut? column was used for purification or extraction. After reaction with xanthydrol, the resultant N-xanthyl acrylamide was determined by GC–MS. The method was validated for various food matrices and showed good linearity, precision and trueness. The limit of detection and limit of quantification ranged 0.5–5 and 5–20?µg?kg?1, respectively. The developed method was applied as an exploratory survey of acrylamide in Japanese foods and the method was shown to be applicable for all samples tested.  相似文献   

20.
Aflatoxins and fumonisins are ubiquitous foodborne toxicants and the co-occurrence of these mycotoxins in human foods represents a significant public health concern, which has been strongly associated with human aflatoxicosis, neural tube defects, as well as many types of primary cancers. In this study the co-contamination of aflatoxin B1 (AFB1) and fumonisin B1 (FB1) in food and human dietary exposure was investigated in residents of three different areas of China. A total of 209 food samples were measured for AFB1 and FB1. The median AFB1 levels were 13.5, 2.3 and 1.3?µg?kg?1 and the median FB1 levels were 2.6, 0.4 and 0.3?mg?kg?1 in corn samples collected from Huaian (a high-risk area for oesophageal cancer), Fusui (a high-risk area for liver cancer) and Huantai (a low-risk area for both oesophageal and liver cancers), respectively. The median level of AFB1 in plant oil of Fusui was the highest (52.3?µg?kg?1) among all food samples analysed. Co-contamination of these two mycotoxins was found in corn, rice and wheat flour. Based on measured food consumption data, the averaged daily dietary intake of AFB1 was 0.397?µg (range?=?0.269–1.218?µg) in residents of Huantai, 1.723?µg (0.224–49.772?µg) in Huaian, and 2.685?µg (1.006–14.534?µg) in Fusui. The averaged FB1 daily dietary intake was 92.4?µg (range?=?55.0–362.1?µg) for residents of Huantai, 460.0?µg (83.2–2894.5?µg) in Huaian, and 138.6?µg (30.0–10,541.6?µg) in Fusui. These data suggest that the co-exposure to AFB1 and FB1 in residents of rural China may contribute to the aetiology of human chronic diseases in high-risk areas.  相似文献   

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