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1.
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   

2.
A rapid and sensitive method has been developed for the determination of the four European Union marker polycyclic aromatic hydrocarbons (PAHs; benz[a]anthracene, chrysene, benzo[b]fluoranthene and benzo[a]pyrene) in some cereal-based foods. The method is based on pressurised liquid extraction (PLE), solid-phase extraction clean-up (SPE) and isotope-dilution gas chromatography with mass-spectrometric detection (GC/MS). The developed method was calibrated for the content range of 0.05–12.5 µg kg?1 (expressed on a product basis). Recoveries of PAH were monitored in each sample via the recovery of 13C-labelled PAHs. Recovery values were in the range between 86% and 91%, with relative standard deviations (RSDs) between 5% and 9%. The achieved limits of detection for all analytes were below 0.05 µg kg?1. The applicability of the method for the analysis of routine samples was studied by the analysis of a set of commercial bread and breakfast cereal samples. In all analysed samples, benzo[a]pyrene (BAP) was the most prevalent PAH with the content between 0.09 and 0.30 µg kg?1. On average, samples showed low levels of the sum of the four EU marker PAHs (ΣPAH4) that ranged between 0.11 and 0.22 µg kg?1 for bread samples and between 0.23 and 0.87 µg kg?1 for breakfast cereal samples. The developed method was found suitable for the determination of PAHs in cereal-based foods like cornflakes and breads with total relative fat contents below 3.5%.  相似文献   

3.
The aim was to evaluate the distribution of aflatoxins and fumonisins in fractions derived from the dry-milling of contaminated maize. Two maize lots with different contamination levels were processed and sampled: the first (maize 1) had aflatoxin B1 (AFB1) and fumonisin B1 (FB1) levels of 3.6 and 5379 µg kg?1, respectively; the second (maize 2) had corresponding levels of 91.1 and 8841 µg kg?1, respectively. The cleaning step reduced AFB1 and FB1 levels by 8 and 11% in maize 1 and by 57 and 34% in maize 2. The subsequent removal of bran and germ led to a further decrease in contamination levels in the products destined for human consumption. In the latter, AFB1 was uniformly distributed, while FB1 was concentrated in the finer size fractions. Contamination of raw maize 1 (3.6 µg kg?1) was below the European Union AFB1 limit of 5 µg kg?1 for unprocessed maize, but among the final products only coarse flour (1.7 µg kg?1) was within the European Union limit of 2 µg kg?1, while grits and fine flour showed higher levels (2.7 and 2.5 µg kg?1, respectively). As regards cleaned maize, a different distribution of the two toxins was observed in the kernels: AFB1 contamination was more superficial and concentrated in germ, while FB1 contamination affected the inner layers of the kernels.  相似文献   

4.
Trichlorfon is a thermally unstable insecticide that can be easily decomposed to dichlorvos at high temperatures. In this study, a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for simultaneous determination of the residues of trichlorfon and dichlorvos in animal tissues. Trichlorfon and dichlorvos in animal tissues were extracted with dichloromethane, homogenized/shaken, concentrated, and determined by LC-MS/MS. The two insecticides can be effectively separated and individually determined. The limits of detection (LODs) of trichlorfon and dichlorvos were 0.04 and 0.07 µg kg?1, respectively; the limits of quantification (LOQs) of the two insecticides were both 5 µg kg?1. The average recoveries for three spiked blank samples at 10, 20 and 40 µg kg?1 were in the range 85–106%, with relative standard deviations (RSDs) below 10.6%, which falls in a reasonable range for the analysis of the two insecticides in animal-derived foods. The method is fit-for-purpose for the simultaneous determination of residues of trichlorfon and dichlorvos in animal tissues.  相似文献   

5.
Furan is a suspected human carcinogen that is formed in some processed foods at low ng per g levels. Recent improvements in analytical methodology and scientific instrumentation have made it possible to accurately measure the amount of furan in a wide variety of foods. Results from analysis of more than 300 processed foods are presented. Furan was found at levels ranging from non-detectable (LOD, 0.2–0.9 ng g?1) to over 100 ng g?1. Exposure estimates for several adult food types were calculated, with brewed coffee being the major source of furan in the adult diet (0.15 µg kg?1 body weight day?1). Estimates of mean exposure to furan for different subpopulations were calculated. For consumers 2 years and older, the intake is estimated to be about 0.2 µg kg?1 body weight day?1.  相似文献   

6.
ABSTRACT

The aim of this research was to evaluate dietary exposure to aflatoxin B1 (AFB1) in corn arepas in Colombia. In addition, in this study an assessment considering compliance to the maximum level of AFB1 (4 µg kg?1) for this food was conducted. AFB1 concentration data in corn arepas were obtained from 168 samples. The samples were collected from factories in 16 departments in Colombia. AFB1 was quantified by High-Performance Liquid Chromatography with a fluorescence detector. Consumption data and body weight (b.w.) were measured from the 2005 Colombian National Survey of Nutritional Status. Probabilistic estimates were made by Monte Carlo simulation of dietary exposure and margin of exposure (MOE) segmented by age group. The results showed that 27% of corn arepa samples were contaminated with AFB1, with an average concentration of 15.1 µg kg?1 and a maximum value of 111.1 µg kg?1. The stochastic dietary exposure assessment showed that the age group most exposed was children between 4 and 8 years old (10.014 ng (kg b.w. day)?1). In addition, the MOE values for all age groups were lower than 10,000, indicating a potential risk for consumers. However, in the scenario where AFB1 concentration level complies with the maximum limit of 4 µg kg?1 AFB1, the level of concern could be reduced for the adult population between 14 and 64 years old because the MOE value is above 10,000.  相似文献   

7.
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   

8.
A survey was conducted to determine the occurrence of fumonisin B1, B2 and B3 during 2007 in 186 samples of organic and conventional locally available corn products. Samples included baby food (n = 62), corn flour (11), cornflakes (23), pasta (14), cookies (17) and other corn products (59) were obtained from popular markets of Valencia (Spain) and Perugia (Italy). The analytical method used pressurized liquid extraction and liquid chromatography/electrospray ionization tandem mass spectrometry with a triple quadrupole (QqQ) analyser. Of the 104 Spanish samples, 22% contained levels in the range of 2–449 µg kg?1, 2–229 µg kg?1 and 6–105 µg kg?1 for FB1, FB2 and FB3, respectively, while 19 (23%) of the 82 Italian samples were positive with quantifiable levels between 2–235 µg kg?1, 3–187 µg kg?1, and 4–40 µg kg?1 for fumonisins B1, B2 and B3, respectively. Overall, none of the Italian samples and only one organic baby food sample from a Spanish market was above the maximum permitted levels established by European legislation. Fumonisins were found mostly in corn flour followed by cookies and cornflakes. Eleven samples from Spain and nine samples from Italy were organic products, being contaminated the 72% and 77% of the samples, respectively. Analysis of the results showed that levels of fumonisins in corn products were similar in Italy and Spain. The safety of fumonisin intake through corn products was demonstrated by the calculation of the estimated daily intake of both populations considering organic and conventional products separately, which ranged from 1.7 × 10?3 to 0.72 µg kg?1 bw day?1 and comparing them with the provisional maximum total daily intake (PMTDI) of 2 µg kg?1 bw day?1 established by the European Union.  相似文献   

9.
One hundred and forty-six samples of animal feed (barley, n = 60; wheat bran, n = 22; wheat dry pulp, n = 29; and canola meal, n = 35) were collected in 2011 from Mashhad (Khorasan, Iran). Aflatoxins (AFs) were determined in these samples after immunoaffinity column clean-up by high-performance liquid chromatography (HPLC) with fluorescence detection. Aflatoxin B1 (AFB1) contamination was found in 28 samples: in five of the barley samples (8.3%) at a mean level of 0.48 µg·kg?1, in two wheat bran samples (9.0%) at a mean level of 0.88 µg·kg?1, in 10 wheat dry pulp samples (34.5%) at a mean level of 0.30 µg·kg?1 and in 11 canola meal samples (31.4%) at a mean level of 0.92 µg·kg?1. AFB1 levels were below the maximum levels of Iran regulations (5 µg·kg?1) and the EU maximum limit (5 µg·kg?1).  相似文献   

10.
A method based on gas chromatography/ tandem mass spectrometry was used to assess levels of 16 EU priority polycyclic aromatic hydrocarbons (PAHs) in 48 preserved food products in oil including foods such as vegetables in oil, fish in oil and oil-based sauces obtained from the Italian market. The benzo[a]pyrene concentrations ranged from <0.04 to 0.40 µg kg?1, and 72.9% of the samples showed detectable levels of this compound. The highest contamination level was observed for chrysene with three additional PAHs (benzo[a]anthracene, benzo[b]fluoranthene and benzo[c]fluorene) giving mean values higher than the mean value for benzo[a]pyrene. Chrysene was detected in all the samples at concentrations ranging from 0.07 to 1.80 µg kg?1 (median 0.31 µg kg?1). The contamination expressed as PAH4 (sum of benzo(a)pyrene, chrysene, benzo(a)anthracene and benzo(b)fluoranthene), for which the maximum tolerable limit has been set by Commission Regulation (EU) No. 835/2011, varied between 0.10 and 2.94 µg kg?1.  相似文献   

11.
A survey of 11 mycotoxins in 348 wheat flour samples marketed in Hebei province of China were analysed by liquid chromatography-tandem mass spectrometry, was carried out. The selected mycotoxins consisted of four aflatoxins (AFs: AFB1, AFB2, AFG1 and AFG2) and seven Fusarium toxins, i.e. deoxynivalenol (DON), nivalenol, 3-acetyldeoxynivalenol and 15-acetyldeoxynivalenol, zearalenone, Fusarenon-X and deoxynivalenol-3-glucoside. Results indicated that most of the wheat samples analysed were contaminated with mycotoxins. Wheat was most susceptible to DON (91.4% contamination), with a mean level of 240 μg kg?1. On average the probable daily intake (PDI, expressed as µg kg?1 body weight day?1) of mycotoxins was within the provisional maximum tolerable daily intake (PMTDI, 2.0 µg kg?1 of body weight day?1) as set by the Joint FAO/WHO Expert Committee on Food Additives. Nevertheless, exposure assessment revealed that the maximum PDI of mycotoxins was 4.06 µg kg?1 body weight day?1, which was twice the PMTDI value. Thus, consistent monitoring is recommended, as to keep the contamination level under control.  相似文献   

12.
BACKGROUND: Maize–bambara groundnut complementary foods are deficient in calcium, iron, zinc and vitamin A. Food‐to‐food fortification could be cheaper, safer and more easily adopted by local communities compared to the use of chemically pure compounds and vitamins to enrich such foods. RESULTS: Maize–bambara groundnut complementary foods fortified for iron, zinc, calcium and vitamin A by blending with a multi‐mix (1.41:1:2.25, w/w) of processed roselle calyces, cattle bones, and red palm oil in a 1:2.1 (w/w) ratio showed significant increases in calcium, iron, zinc and vitamin A contents of 3.26–4.225, 0.083–0.134 and 0.015–0.017 g kg?1 and 4855.3–7493.7 µgRE kg?1, respectively. CONCLUSION: The maize–bambara groundnut foods had calcium, iron, zinc and vitamin A contents that satisfy the proposed nutrient requirements for infants. Only the maize–bambara groundnut and maize–bambara groundnut malt fermented by backslopping [(MB)b and (MBm)b] containing red palm oil emulsified with Brachystegia eurycoma had calcium contents significantly (P < 0.05) higher than Nutrend, a complementary food produced by Nestle (Nigeria) PLC. These products are from raw materials produced in commercial quantities by rural farmers using household level technologies which the rural and urban poor can more easily access in order to reduce micronutrient malnutrition. Copyright © 2010 Society of Chemical Industry  相似文献   

13.
The aim of this study was to investigate the presence of tetracycline residues in pasteurised cow’s milk using high-performance liquid chromatography coupled with UV/VIS detection to determine the exposure of Brazilian’s population to antibiotic residues. One hundred samples collected from the State of Paraná, Brazil, were analysed. Three of these samples were contaminated at the following concentrations: 121.8 µg·kg?1 for oxytetracycline, 93.5 µg·kg?1 for tetracycline and 134.6 µg·kg?1 for chlortetracycline (61.6 µg·kg?1) and doxycycline (73.0 µg·kg?1). The median tetracycline residue concentration found in the samples was 42.3 µg·kg?1, and the estimated daily intake (EDI) was 0.05 µg Kg?1 bw day?1 in Brazil. These results demonstrate that the occurrence of tetracycline in Brazilian milk was low (3%) and only for 2% above the maximum residue limit, so the risk to the population from the presence of these residues in milk was low (<1% of the acceptable daily intake).  相似文献   

14.
This survey was carried out to evaluate the occurrence of total aflatoxins (AFs; B1+B2+G1+G2) in unpacked composite spices. A total of 75 samples of composite spices such as biryani, karhai, tikka, nihari and korma masalas were collected from local markets of Karachi, Pakistan, and analysed using HPLC technique. The results indicated that AFs were detected in 77% (n = 58) samples ranging from 0.68 to 25.74 µg kg?1 with a mean of 4.63 ± 0.95 µg kg?1. In 88% (n = 66) samples, AFs level was below the maximum limits (ML = 10 µg kg?1) as imposed by EU. Furthermore, 61% (n = 46) tested samples contained AFs level between 1 and 10 µg kg?1, 9% (n = 7) exhibited AFs contamination ranged 10?20 µg kg?1 and only 3% (n = 2) of the investigated samples contained AFs levels higher than the ML of 20 µg kg?1 for total aflatoxins as set by the USA. It was concluded that there is need to establish a strict and continuous national monitoring plan to improve safety and quality of spices in Pakistan.  相似文献   

15.
Aflatoxin B1 (AFB1) levels were evaluated in betel nuts (Areca catechu L.) being imported to Pakistan during 2010–2011. In total, 278 betel nut samples (India = 21, Indonesia = 51, Sri-Lanka = 34 and Thailand = 172) were received from the Department of Customs and were analysed by thin layer chromatography (TLC). All Indian origin betel nuts showed AFB1 contamination ranging from 11.7–262.0 µg kg?1 with a mean of 92.5 µg kg?1. Among Indonesian and Sri Lankan shipments, 80.4% and 73.5% betel nuts were contaminated with AFB1 ranging between 3.3–39.2 and 6.5–103.4 µg kg?1 with a mean of 11.6 and 35.0 µg kg?1, respectively. However, only 30.2% of Thailand origin samples showed AFB1 contamination ranging 3.3–77.0 µg kg?1 with a mean of 6.6 µg kg?1. The widespread occurrence of AFB1 increases the hazard associated with betel nuts. Thus, strict control is a pre-requisite for the production and import/export of psychoactive substances as betel nuts.  相似文献   

16.
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   

17.
The purpose of this study was to measure acrylamide (AA) levels and selected parameters of different traditional Turkish coffees. AA, 5-hydroxymethylfurfural (HMF), total reducing sugar, protein, pH, moisture, dry matter (DM) as well as ash, caffeine and soluble solids content (SSC) in DM, L*, a*, b* colour parameters of coffee samples were determined and the correlation between AA level and these parameters were investigated. A total of 36 coffee samples (20 Turkish, 8 Dibek and 8 Terebinth coffee) from the Turkish market were examined. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was validated for the detection and quantitation of AA in coffee samples. The calibration curve was linear (R2 ≥ 0.999) over the range of 30–1000 μg kg?1. The limit of detection (LOD) and limit of quantification (LOQ) were found as 4.6 μg kg?1 and 15.5 μg kg?1, respectively. The amounts of AA in analysed coffee samples were in the range 31.1 ± 0.6 to 323.4 ± 5.4 µg kg?1. The highest mean AA levels were found in Terebinth coffees (240.3 μg kg?1) followed by Turkish coffees (204.3 µg kg?1) and then Dibek coffees (78.6 µg kg?1). No tested Turkish coffee samples had an AA concentration above the indicative value (450 µg kg?1) for roast coffee recommended by the European Commission (EC) in 2011. In addition, a strong positive correlation was found between HMF values and AA amounts of selected coffee types.  相似文献   

18.
Leuco crystal violet (LCV) and leuco malachite green (LMG) are the main metabolites of two dyes that are forbidden for use in food production, but can be present at low background concentration in novel Atlantic salmon feed ingredients such as processed animal proteins (animal by-product [ABP]). In this study, the potential transfer of dietary LCV or LMG to the fillet of farmed Atlantic salmon was investigated. The uptake and elimination rate kinetics were determined in seawater-adapted Atlantic salmon (initial weight 587 ± 148 g) fed two levels of either LCV- or LMG-enriched diets (~500 and 4000 µg kg?1, respectively) for 40 days, followed by a 90-day depuration period with feeding on control diets (<0.15 μg kg?1 LCV and LMG). A three-compartmental model was developed, based on a fillet fat, fillet muscle and a central body compartment comprising all other tissues. Model calibrations showed a good fit with measured values during overall uptake and elimination period; however, the model poorly predicted the short-term (days) peak measured values at the end of the exposure period. The model was used to simulate the long-term (>16 months) LCV and LMG feed-to-fillet transfer in Atlantic salmon under realistic farming conditions such as the seasonal fluctuations in feed intake, growth and fillet fat deposition. The model predictions gave highest expected LCV and LMG fillet concentrations of approximately 0.12 and 0.45 μg kg?1, depending on the dietary levels of ABP and background level of LCV and LMG contamination. These levels are under the reference point for action of 2 µg kg?1 for the sum of MG and LMG that EFSA assessed as adequate to protect public health. However, for LCV, the predicted highest levels exceed the analytical decision limit (CCα) of 0.15 µg kg?1 for the method used in this paper.  相似文献   

19.
The occurrence of aflatoxins (AF) B1, B2, G1, G2 and cyclopiazonic acid (CPA) in feeds, and AFM1 and CPA in milk was determined in dairy farms located in the northeastern region of São Paulo state, Brazil, between October 2005 and February 2006. AF and CPA determinations were performed by HPLC. AFB1 was found in 42% of feed at levels of 1.0–26.4 µg kg?1 (mean: 7.1 ± 7.2 µg kg?1). The concentrations of AFM1 in raw milk varied between 0.010 and 0.645 µg l?1 (mean: 0.104 ± 0.138 µg l?1). Only one sample was above the tolerance limit adopted in Brazil (0.50 µg l?1) for AFM1 in milk. Regarding CPA in feed, six (12%) samples showed concentrations of 12.5–153.3 µg kg?1 (mean: 57.6 ± 48.7 µg kg?1). CPA was detected in only three milk samples (6%) at levels of 6.4, 8.8 and 9.1 µg l?1. Concentrations of aflatoxins and CPA in feed and milk were relatively low, although the high frequency of both mycotoxins indicates the necessity to continuously monitor dairy farms to prevent contamination of feed ingredients.  相似文献   

20.
A total of 635 raw milk samples from 45 dairy farms, from three regions of São Paulo state – Brazil, were evaluated during 15 months for aflatoxin M1 (AFM1). AFM1 was determined by high performance liquid chromatograph with fluorescence detection. AFM1 was detected (>0.003 µg kg?1) in 72.9%, 56.3% and 27.5% of the samples from Bauru, Araçatuba and Vale do Paraíba regions, respectively. The mean AFM1 contamination considering all the samples was 0.021 µg kg?1. Furthermore, the concentration of AFM1 was quite different among Bauru (0.038 µg kg?1), Araçatuba (0.017 µg kg?1) and Vale do Paraíba (<0.01 µg kg?1) regions. Only three samples (0.5%) had higher contamination than the tolerated limit in Brazil (0.50 µg kg?1) and 64 samples (10.1%) had a higher contamination than the maximum limit as set by the European Union (0.050 µg kg?1). The estimated AFM1 daily intake was 0.358 and 0.120 ng kg?1 body weight per day for children and adults, respectively.  相似文献   

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