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1.
Contamination sources of polycyclic aromatic hydrocarbons (PAHs) in the raw material, oil production and storage processes of wood-pressed rapeseed oil were investigated in this study. The results showed that benzo[a]pyrene (BaP) and PAH4 (sum of BaP, benzo[a]fluoranthene, benzo[b]fluoranthene and chrysene) were unevenly distributed in the kernel (0.56–0.98 and 2.84–8.64 μg/kg, respectively) and hull (1.53–3.17 and 13.49–22.31 μg/kg, respectively) of the rapeseed raw materials. The contents of BaP and PAH4 continuously increased during the process of wood-pressed rapeseed oil, ranging from 2.21 to 10.93 and 9.36 to 40.03 μg/kg, thus demonstrating that a wide range of pollution sources of PAHs existed for the test wood-pressed rapeseed oils. The initial temperature and time of roasting should be controlled at <210°C and <60 min, due to the generation of PAHs in rapeseed by over-roasting. In addition, contact tools and substance such as lubricating oil (from the mill), heat-transfer oil (from roasting machine), rubber gaskets and straws should be properly screened. The BaP and PAH4 of rapeseed placed in the roasting area increased from 0.5 to 2.24 and from 2.08 to 9.03 μg/kg, respectively. Therefore, roasting fume control and treatment systems are necessary and the roasting section should be strictly isolated from the other stages. Storage can slightly lower the PAHs amounts in the rapeseed oil, which made the contents of BaP and PAH4 decrease from 27.00 to 24.70 and from 138.63 to 117.58 μg/kg, respectively. Quality control measures of PAHs in wood-pressed rapeseed oil were proposed and implemented, and the final oil products’ BaP and PAH4 were kept below 2 and 10 μg/kg, respectively, which meets the European Commission Regulation No. 835/2011.  相似文献   

2.
For the analysis of 15 + 1 EU priority PAH in tea and herbal infusions, an online-SPE-LVI-GC-MS method was developed. This method includes sample extraction of the tea and herbal infusions with saponification followed by an automated SPE clean-up step. For brews a liquid–liquid extraction with cyclohexane was performed before an automated SPE clean-up. Gas chromatographic separation was done using an Agilent J&W Select PAH (15 m × 0.15 mm × 0.10 µm) column, which allows the separation of the three benzofluoranthenes as well as triphenylene from chrysene. Method performance criteria such as method linearity, limit of quantitation (LOQ) and repeatability were determined and demonstrated that the method was fit for purpose. The method was used to analyse 15 + 1 EU priority PAH in 91 tea and herbal infusion samples. The levels of PAHs ranged from below 0.5 (LOQ) to 460 µg kg?1, with a median of 4.7 µg kg?1 and a mean of 39 µg kg?1 for BaP, and from below 1.0 (LOQ) to 2700 µg kg?1, with a median of 39 µg kg?1 and a mean of 250 µg kg?1 for total PAH, which were in good agreement with other studies reported in the literature. For the brews prepared under normal house preparation (20 g material in 2 L boiling tap water for 10 min), no total 15 + 1 PAH could be detected above the LOQ. With an extended brewing time of 30 min, a transfer rate between 0.25% and 0.52% could be determined, which results in no exceeding of the maximum limits given by the European Union directive for drinking water (EU Council Directive 98/83/EC).  相似文献   

3.
Pyrrolizidine alkaloids (PAs) are secondary metabolites of plant families such as Asteraceae or Boraginaceae and are suspected to be genotoxic carcinogens. Recent investigations revealed their frequent occurrence in honey and particularly in tea. To obtain a comprehensive overview of the PA content in animal- and plant-derived food from the European market, and to provide a basis for future risk analysis, a total of 1105 samples were collected in 2014 and 2015. These comprised milk and milk products, eggs, meat and meat products, (herbal) teas, and (herbal) food supplements collected in supermarkets, retail shops, and via the internet. PAs were detected in a large proportion of plant-derived foods: 91% of the (herbal) teas and 60% of the food supplements contained at least one individual PA. All types of (herbal) teas investigated were found to contain PAs, with a mean concentration of 460 µg kg?1 dry tea (corresponding to 6.13 µg L?1 in [herbal] tea infusion). The highest mean concentrations were found in rooibos tea (599 µg kg?1 dry tea, 7.99 µg L?1 tea infusion) and the lowest in camomile tea (274 µg kg?1 dry tea, 3.65 µg L?1 tea infusion). Occurrence of PAs in food supplements was found to be highly variable, but in comparable ranges as for (herbal) tea. The highest concentrations were present in supplements containing plant material from known PA-producing plants. In contrast, only 2% of the animal-derived products, in particular 6% of milk samples and 1% of egg samples, contained PAs. Determined levels in milk were relatively low, ranged between 0.05 and 0.17 µg L?1 and only trace amounts of 0.10–0.12 µg kg?1 were found in eggs. No PAs were detected in the other animal-derived products.  相似文献   

4.
Aflatoxin contents in 12 types of herbal teas were determined by high performance liquid chromatography (HPLC) with fluorescence detector using immunoaffinity column clean-up. Forty eight samples were collected from four local herbal shops in Manisa, Turkey. Of the 48 samples analyzed, 43 were aflatoxin positive. The highest concentration of aflatoxin (34.18 µg/kg) was determined in a sample of camomile tea. The occurrence of AFB1, B2, G1 and G2 was found in samples at levels of 54, 29, 71 and 46 %, respectively. Aflatoxin B1, B2, G1 and G2 contamination levels varied from 0 to 14.2, 0 to 12.4, 0 to 13.5 and 0 to 28.7 µg/kg, respectively. Aflatoxin was not detected in five samples consisting of linseed, lime and fennel tea.  相似文献   

5.
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   

6.
ABSTRACT

Bleached olive pomace oil (BOPO) was distilled using a short-path molecular distillation unit to determine the impacts of distillation conditions on the removal of 15 PAHs from the list of 16 EPA-priority pollutant PAHs. The removal of PAHs was achieved at elevated temperatures (110–230°C) and pressures (0.05, 0.5, 5 mbar). The oil was also deodorised at 230°C under 0.5, 1 and 5 mbar pressures to determine the effect of pressure during deodorisation on the removal of PAHs. High-performance liquid chromatography (HPLC) with fluorescence detector (HPLC-FLD) was used for quantifying PAH concentrations in oil samples. PAH concentrations in BOPO were considerably reduced after molecular distillation and both temperature increment and pressure decrease were effective for the removal of PAHs from olive pomace oil. When above 190°C, BaP could be reduced to <2 µg/kg at all pressures. Distillation at 230°C under 0.05 mbar absolute pressure reduced the sum of four PAHs (BaP, Chr, BaA, BbF) to 7 µg/kg, which meets the acceptable levels established by the European Union (10 µg/kg). Deodorisation effectiveness was increased by decreasing absolute pressure, particularly for light PAHs.  相似文献   

7.
ABSTRACT

In this study, levels of benzo[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene (BaP), dibenzo[a,h]anthracene, benzo[g,h,i]perylene and indeno[1,2,3-c,d]pyrene in 412 food items collected from food service facilities in Korea were analysed. The concentrations of the eight polycyclic aromatic hydrocarbons (PAHs) ranged 0.13–0.48 μg/kg. The concentrations of benzo[a]pyrene in all food samples were <1 μg/kg, which is the lowest maximum limit in foods regulated by European Union legislation. PAH contents were employed to conduct exposure and risk assessment. The chronic daily intake of PAHs from 412 food samples was 5.48 × 10–6-4.70 ×x 10–4 µg-TEQBaP/kg/day with margins of exposure of 1.04 × 109-1.16 × 1011.  相似文献   

8.
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   

9.
The presence of polycyclic aromatic hydrocarbons (PAHs) in Italian commercial milk samples is reported. The study was carried out on lactating (cow and goat) and plant (rice, soya, oat) milk. The quantitative determination involved liquid–liquid extraction of PAHs, a pre-concentration and determination by HPLC using a fluorescence detector. The recovery of analytes was in the range of 70–115%. The precision of the method was found to be between 6% and 24%. The detection limit ranged from 0.66 to 33.3 µg l–1 corresponding to 0.03–1.66 µg kg–1 milk (wet weight), at a signal-to-noise ratio of 3, depending on the compound. By this procedure, the levels of more volatile PAHs (two to three aromatic rings) were confirmed in 34 commercial milk and three plant milk samples, whereas benzo[a]pyrene was found only in five pasteurised milk samples at a mean concentration of 0.17 µg kg–1 milk. These results provide evidence that PAH levels are influenced by heat treatments and skimming processes of milk production.  相似文献   

10.
Tea is one of the most widely consumed beverages in the world preceded only by water. In some culture style of tea plant, urea fertilizer is sprayed on tea leaf in order to increase crop output; besides, in some processing method of green tea, urea is illegally added to maintain tea’s vivid color. The above-mentioned process may unavoidably cause urea residue, and prolonged or repeated exposure of body to urea may cause adverse effects. In this work, an easy and reliable hydrophilic interaction liquid chromatography/mass spectrometry analytical method for determination of urea in tea was firstly validated; the method exhibited a linear response from 4 to 60 μg mL?1 (R 2?>?0.9996), the limit of quantitation for urea is 4 μg mL?1, the mean recoveries of urea spiked at levels of 10 and 20 μg mL?1 were 95–110 %, and the relative standard deviations of intra- and inter-day measurements were less than 7.8 %. The method was later successfully applied to the analysis of urea residue in some market tea samples. The result showed that there is obvious urea contamination in some market teas, and the contamination percentage is especially high in green tea samples. Among the samples investigated, urea was detected at concentration ranges of 24.02–46.02 mg/kg. Some attention should be paid on the health effect resulting from such urea contamination in tea.  相似文献   

11.
ABSTRACT

The traditional smoking procedure, which is the use of open fire, can lead to the formation of PAHs in sausages. The aim of this paper was to assess the types and concentrations of 16 PAHs in 30 samples of Slavonska kobasica, a traditional smoked sausage. In general, some samples showed high values of anthracene and acenaphthylene. In one sample, acenaphthylene reached the value of 1050 µg/kg and in another 1491 µg/kg anthracene was measured. Cancerogenic benzo(a)pyrene content was little above the maximum limit of 5 µg/kg in four samples, but mainly remained below the limit of quantification. PAH4 (i.c. benzo(a)anthracene, chrysene, benzo(b)fluoranthene and benzo(a)pyrene) were above the maximum limit of 30 µg/kg in three samples. Generally, it can be noted from the results that samples with high PAH4 and benzo(a)pyrene concentrations also have high PAH16 concentrations.  相似文献   

12.
This study investigates the concentration profiles of selected polycyclic aromatic hydrocarbon (PAH) fractions in selected processed meats, in order to evaluate their dietary and health implications. Smoked, grilled and boiled meat products were bought from different locations in Cape Town and Cape Town environs. PAHs were extracted from each meat sample according to standard methods. The concentrations of benzo[k]fluoranthene (BkP), benzo[a]pyrene (BaP), indeno[1, 2, 3-cd]pyrene (IP), and benzo[g, h, i]perylene(BghiP) in the processed meat extracts were determined using a gas chromatograph coupled with flame ionization detector. Total PAH concentrations in smoked, grilled and boiled chicken fillets, pork, and beef stripes were ranged 2.79, 0.99, 2.33 μg/kg; 19.11, 11.17, 15.04 μg/kg; and 14.84, 9.29, 7.20 μg/kg respectively. There were significant differences (p > 0.05) in the concentration levels of PAHs detected in different types, with the highest levels observed in smoked pork meat. The concentration of BkP, BaP, IP and BghiP detected in the various meat samples were below the EU and WHO dietary exposure limit.  相似文献   

13.
Acrylamide content in deep-fried snacks from 20 different production sites of South Indian province of Kerala (80 samples representing 4 important product categories) were determined using a modified high performance liquid chromatography (HPLC)–diode array detector (DAD) method. The limit of detection and the limit of quantification for this method were 1.04 and 3.17 μg/kg, respectively. The mean recoveries of acrylamide obtained by using spiked samples ranged between 90% and 103%, which shows good extraction efficiency. Acrylamide concentrations in the four groups of snacks ranged from 82.0 to 4245.6 µg/kg for potato chips, 46.2–2431.4 µg/kg for jack chips, 24.8–1959.8 µg/kg for sweet plantain chips and 14.7–1690.5 µg/kg for plantain chips. These are the most widely consumed snacks in South India, and the results revealed reasonable levels of acrylamide in these foods, which indicated the general risk of consumer exposure.  相似文献   

14.
A total of 77 traditionally smoked meat samples produced in Latvia, Lithuania, and Estonia were tested for the occurrence of four EU regulated polycyclic aromatic hydrocarbons (PAHs). Levels of PAHs exceeding the EU maximum levels for benzo[a]pyrene and for the sum of four PAHs (PAH4) were detected in 46% and 48% of the samples originating from Latvia. The detected BaP levels in smoked meats ranged from 0.05 to 166 μg kg?1, while the PAH4 content ranged from 0.42 to 628 μg kg?1. The mean dietary exposure to PAHs was estimated at the levels of 5.4 ng BaP/kg bw/day and 36 ng PAH4/kg bw/day. The margin of exposure (MOE) approach was utilised to assess the risks to Latvian consumers due to PAHs and the obtained MOEs were in a range of 7205–24,434, thus indicating a potential concern for consumer health for specific population groups.  相似文献   

15.
The presence of antibiotics in raw milk and milk derivatives poses a threat to human health and can negatively affect the dairy industry. Therefore, the main object of this study was to investigate the transfer of oxytetracycline (OTC), tetracycline (TC), chlortetracycline (CTC) and doxycycline (DC) from raw, experimental milk contaminated with tetracyclines (TCs) to different dairy products: cream, butter, buttermilk, sour milk, whey, curd and cheese. Additionally the effect of the skimming process on TCs concentrations was tested, as well as the influence of low-temperature long-time pasteurisation. The analyses of TCs in milk and dairy products were performed by an LC-MS/MS method. In order to determine TCs residues in dairy products, an analytical method was developed with the same extraction step for all matrices. TCs molecules were inhomogenously distributed between the milk derivative fractions. The highest concentrations were determined in curd and cheese in the ranges 320–482 µg/kg and 280–561 µg/kg, respectively. Low levels of TCs in butter and whey were observed (11.8–41.2 µg/kg). TCs were found in sour milk (66.0–111 µg/kg), cream (85.0–115 µg/kg) and buttermilk (196–221 µg/kg) at much higher levels than in butter and whey, but lower than in curd and cheese. During the skimming process, the highest yield of cream was obtained after the raw milk was held at 2–8°C for 24 h. The differences in concentrations of TCs between whole milk and skimmed milk, expressed as percentages of recovery, were below 19% (recoveries in excess of 81%). The highest content was observed in milk and cream skimmed at 2–8°C. The degradation percentages for TCs during the pasteurisation process (63°C for 30 min) were below 19%.  相似文献   

16.
The concentrations and profiles of polycyclic aromatic hydrocarbons (PAHs) were determined in twenty popular commercial brands of milk in the Nigerian market after saponification with ethanolic KOH and cyclohexane extraction and clean up using a gas chromatography with flame ionization detection. The concentrations of the Σ16 PAHs in these brands of milk ranged from 15.6 to 1,711.8 μg kg?1. The dominant PAH compounds in these brands of milk were 3-and-4-rings PAHs. The dietary intake of BaP, PAH2, PAH4 and PAH8 were 0–53.9 and 0–369.6 ng kg?1 bw day?1 respectively. Using these indicators for occurrence and effects (BaP, PAH2, PAH4 and PAH8) PAHs in food, the margin of exposure were <10,000 in 15–30 % of the brands.  相似文献   

17.
Two polar aminoglycosides, kasugamycin and validamycin-A, were determined in cereals (brown rice, wheat and corn) by high-performance liquid chromatography–tandem mass spectrometry. The analytes were extracted from samples using methanol and water (70:30, v/v) at pH 5.5, purified using both a hydrophilic–hydrophobic-balanced cartridge and a strong cation-exchange cartridge, and then analysed using multiple reaction monitoring in positive electrospray ionisation mode with a special ReproSil 100 C18 high-performance liquid chromatography column. This newly proposed method yielded good sensitivity and excellent chromatographic performance. The limits of quantification for kasugamycin and validamycin-A were 4.1 µg/kg and 1.0 µg/kg, respectively. The recoveries for both compounds at three fortification levels (4, 100 and 500 µg/kg for kasugamycin; 1, 10 and 100 µg/kg for validamycin-A) ranged from 75% to 110%, and the relative standard deviations were below 15%.  相似文献   

18.
There is a lack of information regarding the occurrence and content of contamination of polycyclic aromatic hydrocarbon (PAH) in edible vegetable oils and oilseeds used for oil production in China. By combining the advantages of ultrasound-assisted extraction, low temperature separation and silica SPE purification, a method for the determination of the USEPA, 16 PAHs was developed based on GC-MS to fill this gap. The method recoveries for oils and oilseeds were 84.4–113.8% and 84.3–115.3%, respectively. The LODs and LOQs for 16 PAHs were ranged from 0.06–0.17 and 0.19–0.56 μg kg–1, respectively. Based on the established method, PAH concentrations in 21 edible oils and 17 oilseeds were determined. Almost all the PAHs were found in all the samples tested, especially the light PAHs (LPAHs). Three oil samples exceeded the maximum level of 10 μg kg–1 for BaP set by China. However, five and six oil samples, respectively, exceeded the maximum limits of 2 and 10 μg kg–1 set for BaP and PAH4 by the European Union. The concentrations of PAH16 in oilseed samples were 1.5 times higher than corresponding oil samples. The relationships between PAH4 and PAH8, PAH4 and PAH16 as well as PAH8 and PAH16 indicates that PAH4 is a sufficient surrogate for the contamination level of PAHs in edible oils when compared with PAH8.  相似文献   

19.
The peanut supply chain in Malaysia is dominated by three main stakeholders (importers, manufacturers, retailers). The present study aimed to determine the levels and critical points of aflatoxin and fungal contamination in peanuts along the supply chain. Specifically, two types of raw peanuts and six types of peanut-based products were collected (N = 178). Samples were analysed for aflatoxins by using high-performance liquid chromatography. Results revealed that the aflatoxin contamination was significantly higher (P ≤ 0.05) in raw peanuts and peanut-based products from the retailers. However, there was no significant difference (P ≥ 0.05) in fungal contamination for both types of peanuts except for the total fungal count in raw peanuts from the retailers. Furthermore, raw peanut kernels from the retailers were the most contaminated ones ranged from <LOD to 1021.4 µg/kg (mean: 120.7 µg/kg, median: 1.4 µg/kg) followed by the samples collected from the manufacturers which was ranged from < LOD to 181.9 µg/kg (mean: 20.5 µg/kg, median: 0.0 µg/kg). About 38% and 22% of the samples from the retailers and manufacturers were found to have exceeded the Malaysian Regulation limit (raw peanuts:15 µg/kg; peanut-based products:10 µg/kg), respectively. In contrast, no aflatoxins were detected in samples from the importers. On the other hand, 15.0% and 5.9% of peanut-based products from retailers and manufacturers, respectively, were found to have exceeded the limit. Fungal contamination (0.3–3.6 log CFU/g) was relatively higher in raw peanuts compared to that of peanut-based products (0.6–2.7 log CFU/g). In conclusion, the manufacturers and retailers were the critical points for aflatoxin contamination in peanuts. However, fungal contamination was more critical in the raw peanuts compared to peanut-based products. The study was limited by a minimal number of samples from the importer. Therefore, further investigations on a larger sample size should be conducted to confirm the findings in this present study.  相似文献   

20.
A Quick, Easy, Cheap, Rugged, Effective, and Safe (QuEChERS) method for the determination of benzo[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[a]pyrene (PAH4 including the interfering PAHs triphenylene, cyclopenta[c,d]pyrene, benzo[k]fluoranthene, benzo[j]fluoranthene) was developed and validated with GC-MS/MS in foods of plant and animal origin. PAHs were extracted with acetonitrile, and different clean-ups with various compositions of sorbents, including zirconia-based sorbent (Z-Sep), primary-secondary amine (PSA), anhydrous magnesium sulfate (MgSO4), octadecylsilane (C18 endcapped), and enhanced matrix removal (EMR)-lipid material, were tested. Another important focus of this study was the separation of critical pairs, which is essential for the qualification and quantification of PAH4. To investigate the developed methods, samples were spiked beneath their maximum levels (MLs) and recoveries and peak shapes were compared. The clean-up with 900 mg MgSO4 + 150 mg PSA + 150 mg C18 was chosen to be validated in salmon, mussels, shrimps, bacon, cutlets, wheat flour, curry spice powder, infant formula, infant follow-up formula, and infant foods. Recoveries for all analytes were between 75 and 108%, combined with standard deviation between 2 and 20%. Limits of detection (LODs) and limits of quantification (LOQs) were between 0.04 and 0.34 μg/kg and between 0.1 and 1 μg/kg, respectively.  相似文献   

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