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1.
We investigated in total 80 wine samples of different types and seven grape juice and 23 beer samples purchased from markets in Central Europe in order to understand the arsenic (As) speciation and help assess the potential As toxicity via intake of alcoholic beverages. Generally, total As concentrations in most samples investigated were below the drinking water limit 10 μg l(-1) published by the World Health Organization (WHO); ranging from 0.46 to 21.0 μg l(-1) As in red and white wines and from 0.75 to 13.4 μg l(-1) As in beers. In addition, concentrations of total As in rice wine and in rice beer were 0.63-6.07 and 3.69-8.23 μg l(-1) As, respectively. The total As concentrations in ice wine ranged from 7.94 to 18.8 μg l(-1) As, significantly higher than in white and red wine. Arsenite predominated as the As species in most of the wine samples, whereas arsenate was the dominant species in rice wine, beer and rice beer. Methyl As components were usually minor components in all wine and beer samples. Monomethylarsonic acid, dimethylarsinic acid and two additional unknown As species were frequently found in grape juice, late harvest and ice wine with higher sweetness. After air exposure, arsenite, arsenate, monomethylarsonic acid and dimethylarsinic acid were stable at 4°C for months, probably due to the acidic conditions of wine and beer samples. The presence of sulfite had little influence on As speciation in wine. Despite the predominance of more toxic arsenite and arsenate in wine and beer, the estimated weekly exposure to As (via consumption of beer, wine and rice wine) is low. The As intake per capita is 6.81 μg from beer, <1.93 μg from wine and 0.88 μg from rice wine, estimated using the median of total As concentration multiplied by the average consumption per capita of the corresponding beverage.  相似文献   

2.
A method using ion chromatography–inductively coupled plasma–mass spectrometry (IC–ICP–MS) for the quantification of arsenic species in fruit juices has been developed and validated. The method is capable of quantifying four anionic arsenic species – arsenite (As(III)), arsenate (As(V)), dimethylarsinic acid (DMA) and monomethylarsonic acid (MMA) – in the presence of unretained species such as arsenobetaine (AsB). Method validation was based on repeatability, analysis of reference materials, recovery of fortified samples, and determination of detection and quantification limits. The method was tested for use with apple, pear, cranberry, grape (red, white and purple) juices, as well as several juice blends. Limits of detection were 0.35, 0.41, 0.45 and 0.70?µg?kg?1 for As(III), DMA, MMA and As(V), respectively. Chromatographic recovery was good for most samples (90–107% compared to total arsenic), though recovery for some grape juice samples was lower (67–78%).  相似文献   

3.
Twenty-seven rice samples from Brazil, four parboiled brown, seventeen white and six parboiled white were analysed by ICP-MS for trace element determination. Concentrations of arsenic varied from 58.8 to 216.9?ng?g?1, for cadmium from 6.0 to 20.2?ng?g?1, for antimony from 0.12 to 1.28?ng?g?1, and for uranium from 0.025 to 1.28?ng?g?1. The estimated daily intake through rice consumption was 9.5?µg for As, 2.4?µg for Cd, 0.029?µg for Sb, 0.013?µg for U, 3.1?µg for Co, 0.2?µg for Cu, 85.6?mg for Mg, 1.9?mg for Mn, 333?mg for P, 3.0?µg for Se, 1.6?mg for Zn, 0.9?mg for Rb, and 0.3?µg for V. Found values represent a considerable percentage of the dietary reference intakes and provisional tolerable daily intake for essential and toxic elements, respectively.  相似文献   

4.
Arsenic contamination of rice plants by arsenic-polluted irrigation groundwater could result in high arsenic concentrations in cooked rice. The main objective of the study was to estimate the total and inorganic arsenic intakes in a rural population of West Bengal, India, through both drinking water and cooked rice. Simulated cooking of rice with different levels of arsenic species in the cooking water was carried out. The presence of arsenic in the cooking water was provided by four arsenic species (arsenite, arsenate, methylarsonate or dimethylarsinate) and at three total arsenic concentrations (50,?250 or 500?µg?l?1). The results show that the arsenic concentration in cooked rice is always higher than that in raw rice and range from 227 to 1642?µg?kg?1. The cooking process did not change the arsenic speciation in rice. Cooked rice contributed a mean of 41% to the daily intake of inorganic arsenic. The daily inorganic arsenic intakes for water plus rice were 229, 1024 and 2000?µg?day?1 for initial arsenic concentrations in the cooking water of 50, 250 and 500?µg?arsenic?l?1, respectively, compared with the tolerable daily intake which is 150?µg?day?1.  相似文献   

5.
A total of 150 wines, including 123?dry wines (64 red, 49 white and 10 rosé) and 27 dessert wines (14 red and 13 white), were obtained from various viticulture and oenological practices across Greece during the period 1999–2006 and analyzed for ochratoxin a (OTA) using immunoaffinity clean-up and HPLC with fluorescence detection. There was a high frequency of OTA in commercially available wines (69% positive samples). However, the level of contamination was relatively low, with only one sample marginally reaching the EU permitted maximum level (2.0?µg?l?1). A total of 91% of the samples had OTA concentrations <1.0?µg?l?1. The higher concentrations were found in wines from the southern regions, especially in dessert-type wines. There were no significant differences based on wine color or production years. Furthermore, there was no difference between conventional or organic cropping systems in terms of OTA presence.  相似文献   

6.
A survey on the occurrence of ochratoxin A (OTA) in 240 grape‐based beverages was carried out. Red and white wines from four different Spanish Designations of Origin (n = 160), musts (n = 20), grape juices (n = 10), ordinary wines (n = 20), special wines (Malaga, muscatel, sherry, vermouth, etc) (n = 20) and sparkling wines (n = 10) were assayed for OTA content using immunoaffinity column clean‐up and high‐performance liquid chromatography with fluorimetric detection (detection limit 0.05 µg l?1). Forty‐three (17.9%) of the samples tested contained detectable levels of OTA. The overall mean OTA concentration in red and white wines of Designations of Origin was 0.30 and 0.18 µg l?1 respectively (ranges 0.05–3.19 and 0.05–1.13 µg l?1 respectively). The percentage of wine samples with detectable amounts of OTA was higher for red (18.3%) than for white (10%) wines. OTA was also found in two of 10 red ordinary wines (0.68 and 4.24 µg l?1), whereas none of 10 white ordinary wines contained OTA. The mean OTA amount detected in sparkling wines was 0.44 µg l?1 (range 0.14–0.71 µg l?1). Two of 20 must samples contained OTA at low levels (0.08 and 0.18 µg l?1), while none of 10 grape juice samples contained OTA. Highest amounts of OTA were found in special wines (45%), with a maximum of 15.25 µg l?1 in a muscatel sample. Copyright © 2004 Society of Chemical Industry  相似文献   

7.
Arsenite and arsenate speciation was performed in 121 commercially purchased samples of 12 rice types to understand their relative relevance in rice grain. General effectiveness of a recently developed extraction protocol based on 0.28 M nitric acid at 95 °C was verified by checking the recovery of total grain arsenic and by comparing arsenic speciation in NIST-CRM-1568a, NMIJ-CRM-7503a and IMEP-107 with certificated and literature values. The arsenic speciation highlights the predominance of arsenite in 115 and dimethylarsinic acid in six samples and common minor components including arsenate, monomethylarsonic acid and two unknown arsenical species. Our data also indicate potential influences of other trace elements on As speciation in rice grain. Averagely, arsenite accounts for 90% of inorganic grain arsenic regardless of geographic origin, rice type, grain size, cultural practice and polish treatment. The high arsenite predominance indicates an elevated toxic effect of arsenic in rice than is perceived to date.  相似文献   

8.
Although the need for policy development on arsenic (As) in rice has been recognized and a legally enforceable maximum contaminant level (MCL) for inorganic arsenic (Asi) in rice has been established in China, evidence reported in this article indicates that the risk of exposure to As for the Chinese population through rice is still underestimated. Polished rice from various production regions of China was analyzed for total As and arsenic species using HPLC–ICPMS. Total As concentration ranged 65.3–274.2 ng g?1, with an average value of 114.4 ng g?1. Four arsenic species, including arsenite (As(III)), arsenate (As(V)), dimethylarsinic acid (DMA) and monomethylarsonic acid (MMA), were detected in most rice samples. The Asi (As(III) + As(V)) species was predominant, accounting for approximately 72% of the total As in rice, with a mean concentration of 82.0 ng g?1. In assessing the risk from As in rice, we found that As intake for the Chinese population through rice is higher than from drinking water, with a 37.6% contribution to the maximum tolerable daily intake (MTDI) of As recommended by World Health Organization (WHO), compared with 1.5% from drinking water. Compared to other countries, the risk for the Chinese from exposure to As through rice is more severe due to the large rice consumption in China. Therefore, not only the scientific community but also local authorities should take this risk seriously. Furthermore, more stringent legislation of the MCL for rice should be enacted to protect the Chinese consumer from a high intake of As.  相似文献   

9.
Beer is one of the most popular beverages worldwide. Malted cereal grains are among the basic ingredients and hence mycotoxin contamination might occur. Previous studies reported the presence of the Fusarium mycotoxins deoxynivalenol (DON) and 3-acetyl-deoxynivalenol (3ADON), as well as of the masked mycotoxin deoxynivalenol-3-glucoside (D3G) in beer. In the present survey, 374?beer samples from 38?countries with a focus on Austrian (156) and German (64) beers were analysed for the presence of D3G, DON and 3ADON. Beers were assigned to the following six categories: pale (217), wheat (46), dark (47), bock (20), nonalcoholic beers (19) and shandies (25). In total, 348 and 289 beers (93 and 77%, respectively) contained D3G and DON at the levels above the limit of detection, whereas 3ADON was not detected in any of the samples. Average concentrations of all beers were 6.9?µg?L?1 for D3G and 8.4?µg?L?1 in the case of DON. Nonalcoholic beers and shandies showed the lowest contaminations, 1.5 and 3.2?µg?L?1 for D3G and 2.7 and 4.4?µg?L?1 for DON, respectively. In bock beers characterised by a higher gravity, a significant trichothecene load of 14.8?µg?L?1 D3G and 12.4?µg?L?1 DON was found. The highest contamination (81?µg?L?1 D3G, 89?µg?L?1 DON) was detected in a pale beer from Austria, underlining the importance of this study for food safety. The molar D3G to DON ratio ranged between 0.11 and 1.25 and was 0.56 on average. Concluding, the average contamination of beer is not of toxicological concern for moderate beer drinkers. However, in the case of heavy beer drinkers, beer consumption may considerably contribute to the overall intake of DON, which might even lead to exceeding the maximum tolerable limits established for this Fusarium toxin.  相似文献   

10.
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   

11.
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   

12.
A slurry sampling method is proposed for the determination of iron and zinc in baby food by flame atomic absorption spectrometry without sample digestion prior to analysis. The effect of slurry concentration (the ratio of solid sample to total slurry volume), different acids at various concentrations as diluent and the addition of dispersant on accuracy and precision were investigated. The samples were dried at 105°C overnight and ground using an agate mortar. To obtain quantitative recoveries, 500?mg of sample was slurried in 20?ml of 0.05% Triton X-114 containing 0.1?M HNO3, homogenised using a high-performance overhead disperser at 15,000?rpm for 5?min and directly aspirated into the flame. The accuracy of the method was tested by determination of analytes in various certified reference materials. The limits of detection of the method (N?=?10; 3σ) for iron and zinc were 5.5 and 3.4?µg?g?1, respectively, using a very dilute slurry of baby food, which gave a very low background signal. Finally, the proposed method was applied to the determination of iron and zinc in different baby food samples obtained from markets in Turkey. The range of iron and zinc content for the samples were 33–76 and 15–73?µg?g?1, respectively.  相似文献   

13.
A monoclonal antibody against zearalenone (ZEA) was produced and used successfully to develop a direct competitive enzyme-linked immunosorbent assay (DC-ELISA) for the analysis of ZEA in cereals. This DC-ELISA had a limit of detection of 0.15?±?0.02 µg l?1 and an IC50 value of 1.13?±?0.16 µg l?1. Matrix interference was minimized by dilution of the sample extract before ELISA assays. Aqueous methanol (80%) gave good extraction efficiencies, and the recovery from spiked rice, barley, and corn samples averaged between 87 and 112%. Although ZEA was detected in seven (9%) of 80 rice samples and in eight (16%) of 50 barley samples, the concentration of ZEA in samples was around or below the limit of detection of DC-ELISA. Among 38 corn samples, ZEA was detected in nine (24%) samples in the range 41.0–909.8 µg kg?1. Re-analysis of the ELISA-positive corn samples by high-performance liquid chromatography (HPLC) confirmed that seven (18%) corn samples were positive. The ZEA results for corn showed very good agreement between DC-ELISA and a commercial AgraQant® zearalenone kit (r 2?=?0.98). Thus, the monoclonal antibody-based DC-ELISA could be applied to the preliminary screening of ZEA contamination when analysis of a large sample number is needed.  相似文献   

14.
ABSTRACT

The aim of this study was to determine levels of 11 mycotoxins, 10 trace elements, and 6 phthalates in rice samples from Serbian and Chinese market. Mycotoxins were not detected in any of the analysed rice samples. Results revealed similar median levels for following elements: Mn, 17.5 and 15.7 mg kg?1; Fe, 2.47 and 2.12 mg kg?1; Cu, 1.95 and 1.59 mg kg?1 in marketed samples from Serbia and China, respectively. Median concentration of Ni in Serbian marketed samples was 1.9 times higher than in Chinese ones. The median levels (µg kg?1) of phthalates ranged from 1.2 (benzylbutyl phthalate [BBP]) – 566 (di(2-ethyl-hexyl) phthalate [DEHP]) and 1.7 (BBP) – 348 (DEHP) in Serbian and Chinese marketed samples, respectively. The results were used to assess daily exposure of Serbian and Chinese adult consumers. The calculated target hazard quotients indicated that the potential risk attributable to the analysed contaminants in rice samples should not be of concern neither for the Serbian nor the Chinese consumers.  相似文献   

15.
Thyreostats are growth-promoters banned in Europe since 1981. The identification of thiouracil (TU) in animal biological matrices can, however, no longer be systematically interpreted as a consequence of illegal administration. Indeed, some experimental results have indicated a causal link between cruciferous-based diet and the presence of TU in urine of bovines. The present study aims at investigating, on a large scale (n?>?1300), the natural occurrence of thiouracil in urine samples collected from different animal species. TU was identified in main breeding animal species: bovine, porcine and ovine. The natural distribution of TU allowed proposing threshold values to differentiate compliant from suspect urine samples. Suggested values are 5.7 and 9.1?µg?l?1 in male adult bovines (6–24?months), 3.1 and 8.1?µg?l?1 in female adult bovines (6–24 months), 7.3 and 17.7?µg?l?1 in calves (<6 months), 3.9 and 8.8?µg?l?1 in female bovines (>24 months), and 2.9 and 4.1?µg?l?1 in porcines at a 95 and 99% confidence level, respectively.  相似文献   

16.
Total concentrations of essential (Cu, Zn, Se and Cr) and non-essential (Hg, Cd, Pb and As) trace elements were measured in the flesh and hepatopancreas of Octopodidae (Eledone moschata, Eledone cirrhosa, Octopus salutii), Sepiidae (Sepia elegans, Sepia orbignyana) and Loliginidae (Illex coindeti, Loligo vulgaris) from the Mediterranean Sea. As expected, the hepatopancreas showed higher metal concentrations than flesh; the only exceptions were Hg and As, which were equally distributed in the two tissues. Regarding the edible portion, the highest toxic metal concentrations were in Octopodidae (Hg: 0.44, Cd: 0.49, Pb: 0.10 µg g?1 wet weight) and Sepiidae (Hg: 0.27, Cd: 0.50, Pb: 0.12 µg g?1 wet weight), while Loliginidae tended to accumulate less metal, especially Hg (Hg: 0.11, Cd: 0.30, Pb: 0.05 µg g?1 wet weight). The other elements showed a heterogeneous distribution among the different cephalopod families. Loliginidae showed the highest Se concentrations (1.18 µg g?1 wet weight), Octopodidae of Cu (37.37 µg g?1 wet weight) and Zn (42.00 µg g?1 wet weight) and Sepiidae of As (61.43 µg g?1 wet weight), while Cr was uniformly distributed among the various families (0.38–0.43 µg g?1 wet weight). In these seafoods, the concentrations of essential and non-essential elements were within the prescribed limits set by various authorities, except for Cu and As. Health risks posed by toxic elements to humans via dietary intake of these mollusks were assessed on the basis on Provisional Tolerable Weekly Intake (PTWI), while the estimated intakes of essential elements were compared to Dietary Reference Intakes (RDIs). A 70-g serving of these mollusks was shown to provide a large contribution to Cd intake (0.89 µg kg?1 body weight), corresponding to 35.6% of PTWI. Concerning the essential elements, the consumption of these mollusks made an important contribution to daily dietary intake of Se, Cu and Zn.  相似文献   

17.
The aim of this research was to determine the fate of aflatoxins (AFs) and fumonisins (FBs) naturally occurring in raw materials (maize grit and malted barley) during four industrial brewing processes. The aflatoxin B1 (AFB1) level in raw materials varied from 0.31 to 14.85 µg kg?1, while the fumonisin B1 (FB1) level (only in maize grit) varied from 1146 to 3194 µg kg?1. The concentration in finished beer ranged from 0.0015 to 0.022 µg l?1 for AFB1 and from 37 to 89 µg l?1 for FB1; the other aflatoxins and fumonisin B2 were not found in beer samples. The average percentage of toxins recovered in finished beer, referring to the amounts contained in raw materials, were 1.5% ± 0.8% for AFB1 and 50.7% ± 4.7% for FB1. These results were mainly due to the different solubility of the two mycotoxins during the mashing process. If raw materials comply with the limits fixed by European Commission Regulations, the contribution of a moderate daily consumption of beer to AFB1 and FB1 intake does not contribute significantly to the exposure of the consumer.  相似文献   

18.
1,3‐Dimethoxybenzene was identified by GC–O, GC–MS and Kovats indices (polar Supelcowax, 1709; non‐polar Rtx‐5MS, 1158) as a new volatile component of port wine. Sensory evaluation described this compound as having a sweet medicinal odour with hazelnut, resinous and woody notes. Respective threshold limits in model wine and port wine were 21 and 47 µg l?1. Quantitative analysis by GC–MS, using a selected characteristic ion (m/z 138), indicated that young port wines from the 1998 vintage contained up to 3 µg l?1 whereas ports from the 1999 vintage contained up to 20 µg l?1. © 2002 Society of Chemical Industry  相似文献   

19.
This study developed and validated a sensitive analytical method for simultaneous screening of four classes of endocrine-disrupting chemicals (i.e. progestogens, androgens, oestrogens and phenols) in milk and powdered milk using ultra-performance liquid chromatography (UPLC) coupled with electrospray ionisation quadrupole time-of-flight mass spectrometry (QTOF-MS). Dansylation of oestrogens and phenols enhanced the ionisation efficiency and shifted the ionisation mode from negative to positive, which allowed for the simultaneous analysis of four EDCs in one chromatographic run. An efficient sample pre-treatment minimised the matrix effects. The mass errors for the precursor and product ions for 26 target compounds varied between ?2.8 and 2.3?mDa; and the limits of detection (signal-to-noise ratio?=?3) for milk and powdered milk were less than 0.04?µg?l?1 and 0.10?µg?kg?1, respectively. The proposed method was successfully used to analyse multiple types of real samples, including normal temperature whole milk, infant formula and whole powdered milk. In 11 samples, two target compounds, progesterone and androstenedione, were detected. The progesterone concentrations ranged from 8.1 to 12.7?µg?l?1 in milk, and from 1.2 to 32.0?µg?kg?1 in infant formulas and whole powdered milks. The androstenedione concentrations varied from 0.39 to 0.79?µg?l?1 in milks, and from 0.29 to 1.2?µg?kg?1 in infant formulas and whole powdered milks. Two post-target compounds, one isomer of oestriol and 5α-dihydroprogesterone, were tentatively identified by post-target analysis in two of 11 real samples.  相似文献   

20.
Biogenic amines in wine may impair sensory wine quality and cause adverse health effects in susceptible individuals. In this study, histamine and other biogenic amines were determined by HPLC after amine derivatisation to dansyl chloride conjugates in 100 selected high-quality red wines made from seven different cultivars. Amine levels varied considerably between different wines. The most abundant amines were putrescine (median?=?19.4?mg?l?1, range?=?2.9–122), histamine (7.2?mg?l?1, 0.5–26.9), and tyramine (3.5?mg?l?1, 1.1–10.7), whereas lower levels were found for isoamylamine (median?=?0.25?mg?l?1), phenylethylamine (0.16?mg?l?1), cadaverine (0.58?mg?l?1), spermidine (1.8?mg?l?1) and tryptamine (0.06?mg?l?1). Positive correlations were observed between isoamylamine and phenylethylamine, and between histamine, putrescine and tyramine levels. Amine concentrations were similar in all wine cultivars except Pinot noir and St. Laurent wines, which showed significantly higher tryptamine and cadaverine levels. The results indicate that levels of histamine and other biogenic amines may vary considerably between red wines independent of grape variety and that high amounts can also be found in high-rated wines. Adopting a legal histamine threshold level of 10?mg?l?1 in the European Union, as formerly introduced in other countries, would have excluded 34% of the investigated wines from the market.  相似文献   

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