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1.
Baby bottles are often made of polycarbonate plastic. Impurities remaining in the bottle from the monomer bisphenol A can migrate from the plastic bottles into baby food, thereby causing a health concern. Previous migration testing of new baby bottles showed only trace migration levels of the substance. In the present work, polycarbonate baby bottles were subjected to simulated use by dishwashing, boiling and brushing. Migration testing performed with both new and used bottles revealed a significant increase in migration of bisphenol A due to use. This finding might be explained by polymer degradation. Bisphenol A was determined in 200-ml samples of water food simulant by a method based on solid-phase extraction followed by gas chromatography coupled with mass spectrometry. The detection limit was 0.1 μg l-1. Twelve different polycarbonate baby bottles were tested by filling them with hot water (100°C) for 1 h. The mean bisphenol A level from new bottles was 0.23 + -0.12 μg l-1, while the mean levels from bottles subjected to simulated use were 8.4 + -4 μg l-1 (dishwashed 51 times) and 6.7 + -4 μg l-1 (dishwashed 169 times), respectively. None of the bottles released bisphenol A at levels that exceed the recently established provisional tolerable daily intake (0.01 mg kg-1 body weight/day) in the European Union.  相似文献   

2.
Liquid-crystalline co-polyesters (e.g. a random copolyester based on p-hydroxybenzoic acid (HBA) and 2-hydroxy-6-naphthoic acid (HNA) known as Vectra A950) offer good barrier properties, but for food-contact use require overall and specific migration testing. For Vectra A950 films, the highest overall migration level obtained was 2.3 mg kg-1 in olive oil (10 days at 40°C) well below the EC limit of 60 mg kg-1. The highest specific migration for p-hydroxybenzoic acid was 15.2 μg dm-2 in olive oil (2h at 175°C). For 2-hydroxy-6-naphthoic acid, the highest value obtained was 4.3 μg dm-2 in 10% ethanol (4h at 100°C), although it was not on the EC positive and cannot yet be used for food-contact materials. At conditions considered as severe, the estimated daily intake for p-hydroxybenzoic acid was calculated as 11.9 μg/person day-1 and for 2-hydroxy-6-naphthoic acid it was 5.3 μg/person day-1. The results exceed the threshold of regulation of 1.5 μg/person day-1.  相似文献   

3.
A dipstick assay for the simultaneous determination of atrazine and carbaryl in vegetable samples was developed. The analytical method involved a fast extraction procedure followed by a multi-strip membrane test. The assay took 10 min, with a detection limit (naked eye) of 10 and 200 µg l-1 for atrazine and carbaryl, respectively. The cross-reactivities to related compounds tested were negligible except for propazine. Quantification of the pesticides was carried out by measuring the dot colour with a spectrophotometer. IC50 values (inhibition constant at 50% of the maximum binding) of 2.04 μg l-1 for atrazine and 92.8 μg l-1 for carbaryl were achieved by this approach. Vegetable samples were extracted with MeOH. The proposed methodology was used to analyse atrazine and carbaryl and check for compliance with European Union maximum residue levels for vegetables. Recoveries (75-105%) were in agreement with those obtained by GC/MS or HPLC. Standard curves using 25% methanol/75% TBS were used for food sample assays using a multi-analyte dipstick. IC50 values were 9.2 μg l-1 for atrazine and 179.2 μg l-1 for cabaryl.  相似文献   

4.
An improved specific analytical method for ochratoxin A (OTA) determination in olive oil is described, using a methanolic-aqueous extraction, an immunoaffinity column clean up step and high-pressure liquid chromatography with fluorescence detection. The mean recovery was found at 108% (relative standard deviation, RSD = 4.7%) and the detection limit (DL) was estimated at 4.6 ng kg-1. Along with OTA, aflatoxin B1 (AFB1) was determined using the same extract. The recovery factor was 84.8% (RSD = 17.8%) and the DL was 56 ng kg-1 olive oil. Both determinations were applied in 50 samples of olive oil originated from representative regions of Greece. Results revealed the presence of OTA in 88% of samples tested (n = 44, mean 267 ng kg-1). Among them, 10 were contaminated with more than 500 ng kg-1 (median 568 ng kg-1), 10 with 200-500 ng kg-1 (median 260 ng kg-1), 15 with 100-200 ng kg-1 (median 140 ng kg-1), nine with DL-100 (median 60 ng kg-1) and in six samples, OTA was not detectable. Interestingly, most contaminated samples were from Southern Greece. Results of AFB1 determination showed the presence of aflatoxin B1 (60 ng kg-1) in only one olive oil sample also from Southern Greece. The levels of OTA found in Greek olive oil were relatively low as compared with other commodities such as cereals or wine reported in the literature.  相似文献   

5.
In 1999, 116 samples of non-alcoholic beverages were analysed for the intense sweeteners cyclamate, acesulfame-K, aspartame and saccharin. High contents of cyclamate close to the maximum permitted level in 1999 of 400 mg l-1 were found in many soft drinks. The estimated intake of the sweeteners was calculated using the Danish Dietary Survey based on 3098 persons aged 1-80 years. The estimated intake with 90th percentiles of 0.7, 4.0 and 0.2 mg kg-1 body weight (bw) day-1 for acesulfame-K, aspartame and saccharin, respectively, was much lower than the acceptable daily intake (ADI) values of 15, 40 and 2.5 mg kg-1 bw day-1 for acesulfame-K, aspartame and saccharin, respectively. However, the 90th percentile of the estimated cyclamate intake in 1-3 year olds was close to the ADI value of 7 mg kg-1 bw day-1; and the 99th percentile in the 1-10 year olds far exceeded the ADI value. Boys aged 7-10 years had a significantly higher estimated intake of cyclamate than girls. The 90th percentile for the whole population was 1.8 mg kg-1 bw day-1. After the reduction in the maximum permitted level in the European Union in 2004 from 400 to 250 mg cyclamate l-1, the exposure in Denmark can also be expected to be reduced. A new investigation in 2007 should demonstrate whether the problem with high cyclamate intake is now solved.  相似文献   

6.
Aflatoxin B1 (AFB1), B2 (AFB2), G1 (AFG1) and G2 (AFG2) were extracted by matrix solid-phase dispersion with C18 silica and acetonitrile as the eluting solvent, analysed by liquid chromatography with fluorescence detection and confirmed by liquid chromatography with mass spectrometry using an electrospray interface in 58 samples grouped as cereals, dried fruits, herbs and spices, pulses, snacks, and nuts and nut products collected from local markets and supermarkets in Valencia, Spain. All samples analysed by the proposed method were previously studied with an enzyme-linked immunosorbent assay as a screening protocol for the fast detection of mycotoxins. The samples containing residues (3/58) were hazelnut (0.42 and 0.52 μg kg-1 for AFB1 and AFG1, respectively), nut cocktail (0.29 and 0.47 μg kg-1 for AFB1 and AFG1, respectively) and pinhol (0.30 μg kg-1 for AFG1). Such values were below the legislated maximum residue levels for the European Union.  相似文献   

7.
The European Union Baby Food Directive (1999/39/EC), which came into force on 1 July 2002, set legal maximum residue levels at 0.01 mg kg-1 for all pesticides in baby foods. The combination of large volume-difficult matrix introduction (LV-DMI) with gas chromatography-time of flight-mass spectrometry (GC-TOF-MS), described herein, provides the analyst with a simple but rapid alternative GC-MS technique for the multiresidue analysis of pesticides in fruit-based baby foods. Samples were extracted with ethyl acetate in the presence of Na2SO4 and NaHCO3 and the crude extracts were analysed directly using LV-DMI-GC-TOF-MS. The best overall results (98 pesticides quantified satisfactorily at a spiking level of 0.01 mg kg-1) were obtained by analysis of concentrated extracts (2.5 g crop ml-1) using a 30-m column, with a chromatographic run time of 25 min. A good signal-to-noise ratio was obtained at the lowest calibrated level (0.0125 μg ml-1), with excellent linearity achieved over the range 0.0125-0.25 μg ml-1 (equivalent to 0.005-0.1 mg kg-1). Average recoveries for the analysis of five replicate determinations at a spiking level of 0.01 mg kg-1 were between 79 and 114% with relative standard derivations generally less than 20%.  相似文献   

8.
Total mercury was measured in 259 total diet food composites from two Canadian cities. Levels were generally low, with 46% of the composites having concentrations below the limit of detection, which ranged from 0.026 to 0.506 ng g-1. The fish category contained the highest mercury concentrations, which averaged 67 ng g-1 and ranged from 24 to 148 ng g-1. All composites were below the Canadian guideline for total mercury in fish of 0.5 ppm. Dietary intakes of mercury averaged 0.022 μg kg-1 body weight/day (μg kg-1 day-1), and ranged from 0.012 μg kg-1 day-1 for females over 65 years old to 0.062 μg kg-1 day-1 for 0-1-month-old infants. For fish consumers, fish contributed to more than half of the ingested mercury. All intakes were well below Joint FAO/WHO Expert Committee on Food Additives Provisional Tolerable Weekly Intakes, expressed on a daily basis, of 0.71 μg kg-1 day-1 total mercury and 0.47 μg kg-1 day-1 methyl mercury, and also below a recent Health Canada recommended maximum methyl mercury intake of 0.2 μg kg-1 day-1 for children and women of child-bearing age.  相似文献   

9.
Three hundred and twenty samples from the 1999 UK harvest comprising wheat (201 samples), barley (106) and oats (13) were analysed for ochratoxin A and deoxynivalenol. A small number of organic samples was also obtained. Samples were collected from farms, central stores, mills, maltings and ports from across the UK from February to April 2000. Ochratoxin A and deoxynivalenol analysis was by affinity column clean up and high-performance liquid chromatography with fluorescence and ultraviolet light detection, respectively, with limits of detection of 0.2 and 20 μg kg-1. The survey found ochratoxin A at below 5 μg kg-1 in 97% of the samples indicating satisfactory storage conditions. The remaining 3% of the samples contained ochratoxin A at levels between 5.2 and 231 μg kg-1, but none of these samples was intended for human consumption. Deoxynivalenol was detected in 88% of all samples, with 83% below 100 μg kg-1; the maximum level was 600 μg kg-1. Twenty samples containing deoxynivalenol at or above 150 μg kg-1 by high-performance liquid chromatography were all confirmed by gas chromatography/mass spectrometry. Nivalenol was also detected by gas chromatography/mass spectrometry at levels of 50 μg kg-1 or higher in 18 of 20 samples where deoxynivalenol was confirmed.  相似文献   

10.
Migration of the potential endocrine disrupter, bisphenol A (BPA), from 31 polycarbonate (PC) baby bottles into aqueous food simulants was studied under real repetitive use, using a sensitive and fully validated liquid chromatographic method with fluorescence detection. Confirmation of the presence of BPA was performed by liquid chromatography-mass spectrometry (LC-MS). The effects of cleaning in a dishwasher or with a brush, sterilization with boiling water and the temperature of migration were examined. It was shown that temperature was the crucial factor for the migration of BPA from the plastic bottles to water. All samples released BPA in the concentration range 2.4-14.3 µg kg-1 when filled with boiled water and left at ambient temperature for 45 min. The decrease of BPA release in the sterilization water and in the food simulant over 12 cycles of use indicated that the hypothesis of polymer degradation in water is dubious. Estimated infantile dietary exposure, regarding the use of PC baby bottles, ranged between 0.2 and 2.2 µg kg-1 bw day-1, which is below the Tolerable Daily Intake of 50 µg kg-1 bw recently established by EFSA.  相似文献   

11.
Information on the contamination of Danish cereals and cereal products with Fusarium toxins is limited and the last survey is from 1984/1985. In the present study, the occurrence of deoxynivalenol (DON), nivalenol (NIV), HT-2 toxin, T-2 toxin and zearalenone (ZON) was investigated in flour of common wheat, durum wheat and rye. The samples were collected from 1998 to 2001 from both mills and the retail market in Denmark. A total of 190 flour samples were analysed for DON and NIV and about 60 samples for HT-2, T-2 toxin and ZON. DON was most frequently detected with an incidence rate of 78% over all samples for all years. The contamination level varied considerably from year to year, and for wheat and rye the highest incidence and DON concentrations were found in samples from the 1998 harvest. There were regular and heavy rainfalls in Denmark during the flowering period of the crops that year, and DON was found in all samples, with mean concentrations in wheat and rye flour of 191 μg kg-1 (n =14) and 99 μg kg-1 (n =16), respectively. Comparison of data from each harvest year showed higher contents of DON in samples of wheat (range 20-527 μg kg-1) than in rye (20-257 μg kg-1). Contents of NIV, HT-2 toxin and ZON in samples of wheat and rye were generally low, and even in positive samples the contents were close to the detection limit of the methods. The T-2 toxin was detected in only a few of the wheat samples and in low amounts. However, the toxin was found in about 50% of the rye samples collected during 1998-2000, with a mean content of 49 μg kg-1 (n =25). Durum wheat flour showed the highest DON contamination level, and all samples (n =33) collected during 2000 and 2001 contained DON with means and medians above 1100 μg kg-1. Over 70% of the samples contained more than 500 μg kg-1 DON, and the highest observed concentration was 2591 μg kg-1. The concentration of T-2 toxin in durum wheat flour was also high with five of the 10 analysed samples containing more than 100 g kg-1.  相似文献   

12.
Migration of aniline from polyamide cooking utensils into food simulants   总被引:1,自引:0,他引:1  
Migration of aniline from polyamide cooking utensils was investigated. Aniline was found to originate from the application of black colorant in the polyamide 66 raw material. Analysis of polyamide raw material revealed an aniline concentration of 121 ± 13 mg kg-1. The aniline concentration in a cooking utensil (turner) manufactured with 70% polyamide raw material was 82 ± 6 mg kg-1. When testing migration from black coloured samples of turner, whisk and cooking spoon into water simulant at 100°C for 30 min, the migration levels at the third exposure were 39 ± 1, 11 ± 4 and 37 ± 4 μg dm-2, respectively. Hence, these articles were not compliant with respect to the area-based limit for primary aromatic amines (3.33 μg dm-2) set by European Union Directive 2002/72/EC. Repeated testing of a cooking utensil (turner) showed that approximately 100 h use at 100°C was required to reach legal (non-detectable) levels of aromatic amine migration.  相似文献   

13.
A total of 208 samples of commercial pasteurized milk gathered from retail outlets across Japan during the winter season were analysed for aflatoxin M1 (AFM1). Japan was divided into 11 regions from north to south, and nine to 45 milk samples from each region were randomly purchased between December 2001 and February 2002. Each milk sample was cleaned up by an immunoaffinity column, and AFM1 was quantified by liquid chromatography with fluorescence detection in four independent laboratories. The limit of detection of the method was 0.001 μg kg-1. The identity of the putative AFM1 in milk sample was confirmed by the formation of AFM1 hemi-acetal with trifluoroacetic acid. Based on the results obtained with spiked samples (0.05 μg AFM1 kg-1), the mean recovery was 91.4%, the relative standard deviation for repeatability was 4.6%, and the relative standard deviation for reproducibility was 8.0% among four independent laboratories. AFM1 was detected in 207 (99.5%) of 208 milk samples at 0.001-0.029 μg kg-1, with a mean of 0.009 μg kg-1 and a 90th percentile of 0.014 μg kg-1. No significant difference of the level of AFM1 contamination was observed among the regions.  相似文献   

14.
The migration of trimellitic acid and its esters from epoxy anhydride coatings was determined in simulants as well as in canned foods. The most appropriate simulant was a combination of EC simulants B and C: 2% acetic acid/10% ethanol in water. The average migration into food was 900 μg kg-1. This far exceeds the 50 μg kg-1 for which the safety of trimellitic acid and its anhydride is ensured and the Swiss legal limit (QM(T) of 5 mg kg-1 coating). Furthermore, much trimellitic acid migrated as (unidentified) esters, i.e. toxicological testing of free trimellitic acid is inadequate for the material that in reality migrates.  相似文献   

15.
The levels of formaldehyde (FA) and acetaldehyde (AA) in polyethylene terephthalate (PET) bottles and in commercial mineral water are reported. All the water samples bottled in Japan contained detectable levels of FA (10.1-27.9 μg l-1) and AA (44.3-107.8 μg l-1). Of 11 European bottled water samples, eight did not contain either FA or AA, while the remaining three had detectable levels of FA (7.4-13.7 μg l-1) and AA (35.9-46.9 μg l-1). In three North American bottled water samples, two contained FA (13.6 and 19.5 μg l-1) and AA (41.4 and 44.8 μg l-1), and one did not. Regardless of the region of origin, all the sterilized water samples contained FA and AA, whilst in contrast, none of the unsterilized water without carbonate contained FA or AA. Of the carbonated water samples, three contained FA and AA, and one did not. When fortified with FA and AA, the commercial water sample without otherwise detectable FA and AA was able to reduce levels, although the commercial water sample containing FA and AA could not. The presence of bacteria in the commercial water samples was investigated using an ATP-based bioluminescent assay and heterotrophic plate count method. The commercial water without FA and AA contained heterotrophic bacteria, whilst the commercial water with FA and AA did not contain detectable bacteria. It is suggested that in this case both FA and AA migrated from PET materials, but were subsequently decomposed by the heterotrophic bacteria in the unsterilized water.  相似文献   

16.
A survey of the pesticide content of 25 commercially available infant formulae and 30 weaning foods available in New Zealand was undertaken in 1996. It included a representative mixture of imported and New Zealand manufactured infant foods. Three different pesticide screening techniques were used: a high-sensitivity organochlorine screen was carried out on all infant formulae, while a multiresidue screen (organochlorine and organophosphorus pesticides, synthetic pyrethroids, carbamate pesticides, fungicides and herbicides), and a specific screen for dithiocarbamate fungicides were both carried out on all weaning foods and on soy-based infant formulae. All results are expressed on a ready-to-feed basis. Extremely low levels of residues of three organochlorine compounds (p,p'-DDE, p,p'-DDT and dieldrin) were detected in infant formulae samples. Residues of p,p'-DDE were found in seven of 20 milk-based infant formulae at concentrations ranging from 0.03 to 0.5 μg kg-1. Residues of p,p'-DDT were found in one imported milk-based infant formula at 0.7 μg kg-1, and dieldrin residues were detected in four of five soy-based infant formulae at concentrations ranging from 0.05 to 0.08 μg kg-1. The multiresidue pesticide screen detected low levels of residues of two organophosphorus pesticides; azinphos-methyl in one soy-based infant formula at a level of 22 μg kg-1 and pirimiphos-methyl in two cereal-based weaning foods at concentrations of 5 and 14 μg kg-1. None of the other approximately 140 pesticides (including fungicides and herbicides) included in the multiresidue screen were detected in any weaning foods or soy-based infant formulae, at a detection limit of 10 μg kg-1. No residues of dithiocarbamate fungicides were detected in any product analysed, at a detection limit of 100 μg kg-1.  相似文献   

17.
The natural occurrence ofaflatoxin was investigated in layer feed and corn samples brought to Konya Veterinary Control and Research Institute Laboratory between 15 April and 15 December 2002. Seventy-eight samples (52 feeds, 26 corn samples) were analysed for total aflatoxin (B1 + B2 + G1 + G2) by an ELISA screening method. Aflatoxin contamination was determined in 37 feed samples (71.1%) and 15 corn samples (57.7%), with a range of1.5-133 μg kg-1. However, a majority ofthe aflatoxin contamination was less than 5 μg kg-1 (50% within the positive samples). Two feed samples and two corn samples exceeded the maximum tolerated levels in feed (20 μg kg-1) and feedstuffs (50 μg kg-1) for total flatoxin.  相似文献   

18.
Maize samples collected from storage bins and feed mills in Northern Italy between 1995 and 1999 were surveyed for the occurrence of aflatoxin B1 (AFB1), zearalenone (ZEA), deoxynivalenol (DON) and fumonisin (FB1); further, ergosterol was analysed as a fungal growth marker. The incidence and mean content of AFB1 were generally low; nevertheless, a remarkable contamination was found in two samples (109 and 158 μg kg-1), while five others exceeded 20 μg kg-1. DON and ZEA mean levels were significantly higher in 1996 (2716 and 453 μg kg-1) with respect to the other years, when mean contents ranged from 7 to 30% and from 3 to 17%, respectively, expressed in per cent of 1996 contents. FB1 was present in all samples and was by far the most remarkable mycotoxin in Northern Italian maize, with the exception of samples from 1996. The average level was 3064 μg kg-1, 69.6% of samples resulted over 1000 μg kg-1 and 16.9% over 5000 μg kg-1. Significant correlations were found between ergosterol and the major mycotoxin(s) in each year (FB1 in 1995 and 1997-99; ZEA + DON in 1996). Consequently, ergosterol seems to be a good index of the toxicological quality of maize. Climatic conditions influenced the growth of different fungal species. In 1996, the first 20 days of October were extremely rainy; these weather conditions delayed the harvest until the first week of November and favoured the growth of DON and ZEA producing fungi and the synthesis of mycotoxins. On the contrary, the temperate and dry climate of the other years supported the growth of FB1-producing fungi.  相似文献   

19.
A method for the simultaneous quantitative determination of deoxynivalenol (DON), fumonisin B1 (FB1) and zearalenone (ZEN) in maize by liquid chromatography-atmospheric pressure chemical ionization tandem mass spectrometry (LC-APCIMS/MS), using stable isotopically labelled and structural analogues internal standards, is described. The procedure involves accelerated solvent extraction followed by two solid-phase clean-up steps on strong anion exchange resin and a Mycosep® column. Typical recoveries were calculated by spiking blank maize at three different concentrations for deoxynivalenol (200, 400 and 1000 μg kg-1) at 70%, for fumonisin B1 (100, 200 and 1000 μg kg-1) at 90%, and for zearalenone (50, 100 and 200 μg kg-1) at 40%. LC-APCIMS/MS analyses were realized in collision-induced dissociation on an ion-trap instrument to provide a high degree of selectivity and sensitivity. Extraction of ions from two transition reactions, monitored by LC-APCIMS/MS for each analyte, enabled a limit of detection for DON, FB1 and ZEN at, respectively, 10, 20 and 3 μg kg-1, and a limit of quantification at, respectively, 50, 50 and 10 μg kg-1. The robustness of the method was also evaluated with the analysis of wheat samples.  相似文献   

20.
To prevent the illegal use of chloramphenicol (CAP), regulatory control of its residues in food of animal origin is essential. In Slovenia, the monitoring of CAP residues for statutory purpose started in 1991. The results of a 10-year period are presented. CAP residues were determined by capillary gas chromatography (GC) with electron capture detection (ECD) using meta-CAP as an internal standard (ISTD). Before chromatographic determination, analytes were derivatized by silylation. Overall, CAP recovery, adjusted for ISTD, was for bovine muscle tissue and raw cow's milk (in the region of 2-10 μg kg-1) 89 and 102%, respectively, and for whole eggs, 87% (in the region of 1-10 μg kg-1). The use of meta-CAP improved significantly the precision of the method. The detection limit for CAP was 1 μg kg-1, which was sufficiently sensitive for routine use. A total of 1308 random samples of Slovenian origin were analysed from 1991 to 2000, covering all parts of the country. CAP was found only in one milk sample in 1997 at a concentration of 4.6 μg kg-1.  相似文献   

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