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1.
The coccidiostat maduramicin has been approved as a feed additive for chickens and turkeys, although it is prohibited for use in laying hens. In the present study, laying hens were divided into three groups and fed for 14 days with medicated feed containing maduramicin, at three different concentrations: 50, 100 and 500 µg kg?1. Eggs were collected during treatment and for 26 days after the end of feeding with medicated feed. Maduramicin residues were found exclusively in egg yolk, with the highest concentration in egg yolk of 459 µg kg?1 for the highest dose. The maximum concentration of maduramicin in whole egg was 16.6 µg kg?1 for the group receiving feed containing the maximum permitted level of maduramicin in feed (50 µg kg?1). The half-life of elimination of maduramicin, calculated for post-treatment days 1–10, was 6.5 days. Twelve days after drug administration, the concentration of the maduramicin in egg yolk for Group 3 (fed with 500 µg kg?1 maduramicin) still exceeded 20 µg kg?1, while the concentrations for Groups 1 and 2 were 1.2 and 2.7 µg kg?1, respectively.  相似文献   

2.
Decoquinate, a chemical coccidiostat used as a feed additive, can occur in eggs due to cross-contamination of feedstuffs for laying hens. An experiment was designed to assess the transfer of decoquinate to hen eggs and its distribution between egg yolk and egg white. Hens were given the feed containing decoquinate at a cross-contamination level (0.34 mg kg–1) and collected eggs were analysed using an LC-MS/MS method. The plateau level was reached on the eighth day of the experiment and averaged 8.91 µg kg–1, which is far below the maximum level established at 20 µg kg–1 for whole eggs. Decoquinate was deposited mostly in egg yolks (26.2 µg kg–1) and did not deplete completely during 14 days of administration of decoquinate-free feed. The results confirmed that administration of cross-contaminated feed is associated with very low risk of non-compliant residue levels of decoquinate in eggs.  相似文献   

3.
A simple analytical method for the determination of hydrocortisone and progesterone in bovine, swine, and chicken muscle and eggs was developed. Hydrocortisone and progesterone were extracted with acetonitrile and subsequently cleaned-up using an Oasis® HLB mini-cartridge. The method was validated in accordance with Japanese guidelines and exhibited trueness from 86.6% to 104.3% and precision (relative standard deviations (RSDs) of repeatability and within reproducibility were under 8.7% and 11.7%, respectively). The method was applied to 103 bovine muscle, 137 swine muscle, 69 chicken muscle and 52 egg samples that were commercially available in Tokyo, Japan. The hydrocortisone concentration was 0.9–41.2 µg kg?1 in all bovine muscle samples, with an average of 7.7 µg kg?1 and a median of 6.2 µg kg?1. The progesterone concentration in 50 samples exceeded the limit of quantification (LOQ) and reached a maximum of 95.4 µg kg?1. Hydrocortisone was also detected in all swine muscle samples at concentrations of 2.0–56.0 µg kg?1. Its average and median concentrations amounted to 13.1 and 11.3 µg kg?1, respectively. Twenty-three samples contained progesterone levels surpassing the LOQ, with a maximum concentration of 107.0 µg kg?1. No chicken muscle samples contained any of the analytes. The progesterone concentration was 15.5–200.0 µg kg?1 in all egg samples, with an average of 95.4 µg kg?1 and a median of 90.5 µg kg?1.  相似文献   

4.
ABSTRACT

This study determined the levels of pyrrolizidine alkaloids (PAs), including their respective N-oxides, in foodstuffs available in Hong Kong by liquid chromatography-electrospray ionisation tandem mass spectrometry. A total of 234 samples (48 food items) were collected randomly from a local market and analysed. About 50% of samples were found to contain detectable amount of PAs. Amongst the 48 food items, PAs were not detected in 11 food items, including barley flour, beef, cattle liver, pork, pig liver, chicken meat, chicken liver, milk, non-fermented tea, Melissa tea and linden tea. For those found to contain detectable PAs, the summed PA content ranged up to 11,000 µg kg?1. The highest sum of PA content among the 37 food items calculated with lower bound was cumin seed, then followed by oregano, tarragon and herbs de Provence with ranges of 2.5–11,000, 1.5–5100, 8.0–3300 and 18–1300 µg kg?1 respectively. Among the samples, the highest sum of PA content was detected in a cumin seed sample (11,000 µg kg?1), followed by an oregano (5100 µg kg?1), a tarragon (3300 µg kg?1) and a herbs de Provence (1300 µg kg?1). In general, the results of this study agreed well with other published results in peer-reviewed journals, except that the total PAs in honey and specific tea infusion in this study were comparatively lower.  相似文献   

5.
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   

6.
In many countries, ractopamine hydrochloride (RAC) is allowed to be used in animal production as a β-agonist, which is an energy repartitioning agent able to offer economic benefits such as increased muscle and decreased fat deposition, feed conversion improvement and an increase in average daily weight gain. However, some countries have banned its use and established strict traceability programmes because of pharmacological implications of β-agonist residues in meat products. In Brazil, commercial RAC is controlled (5–20 mg kg?1) and only added to pig diet during the last 28 days before slaughter. However, the control is more difficult when co-products, like meat and bone meal (MBM), which can be produced from RAC treated animals, are part of the feed composition. Therefore, a study was undertaken to evaluate the presence of RAC residue concentrations in urine and tissues of gilts (n = 40) in four dietary groups: 0%, 7%, 14% and 21% (w/w) of MBM-containing RAC (53.5 µg kg?1). The concentration of RAC residues in MBM, pig tissues and urine was determined by LC–MS. Low RAC concentrations were detected in muscle, kidney, liver and lungs (limit of detection = 0.15, 0.5, 0.5 and 1.0 µg kg?1, respectively); however, no RAC residues were quantified above the limit of quantification (0.5, 2.5, 2.5 and 2.5 µg kg?1, respectively). In urine, the RAC concentration remained below 1.35 µg L?1. These data suggest that MBM (containing 53.5 µg kg?1 RAC) added to diet up to 21% (w/w) could hamper the trade where RAC is restricted or has zero-tolerance policy.  相似文献   

7.
The aim of this study was to determine the level of bound 3-monochloropropan-1,2-diol in foodstuffs commonly consumed in Hong Kong, China, by an enzymatic hydrolysis indirect method which proved to be free from interferences. A total of 290 samples were picked up randomly from the local market and analysed. About 73% of these samples were found to contain detectable amounts of bound 3-MCPD. Amongst the 73 food items, bound 3-MCPD was not detected in 13 food items, including extra virgin olive oil, beef ball/salami, beef flank, ham/Chinese ham, nuts, seeds, soy sauce, oyster sauce, butter, yoghurt, cream, cheese and milk. For those found to contain detectable bound 3-MCPD, the content ranged up to 2500 µg kg?1. The highest mean bound 3-MCPD content among the 14 food groups was in biscuits (440 [50–860] µg kg?1), followed by fats and oils (390 [n.d.–2500] µg kg?1), snacks (270 [9–1000] µg kg?1), and Chinese pastry (270 [n.d.–1200] µg kg?1). Among the samples, the highest bound 3-MCPD content was in a grape seed oil (2500 µg kg?1), followed by a walnut flaky pastry (1200 µg kg?1) and a grilled corn (1000 µg kg?1). Basically, the results of this study agreed well with other published results in peer-reviewed journals, except for cheese, cream, ham, nuts and seeds.  相似文献   

8.
Lasalocid is a polyether ionophoric coccidiostat used for the prevention of coccidiosis in poultry at a prescribed concentration and during a certain time interval. Due to a public health concern about the presence of coccidiostat residues in poultry, the aim of the present study was to determine the levels of lasalocid residues in the edible tissues of broiler chickens (breast muscle, thigh muscle, heart, liver, gizzard, kidneys and skin/fat) fed commercially produced feed containing 100?mg?kg?1 of lasalocid in complete feed throughout the 5-day withdrawal period (WP). The residues were investigated by liquid chromatography coupled with electrospray ionisation (ESI) tandem mass spectrometry (MS/MS) with triple quadrupole. The limit of detection (LOD) and the limit of quantification (LOQ) of the method were 0.47 and 1.44?µg?kg?1, respectively. The average recovery based on the matrix-fortified calibrations for chicken tissues ranged between 79% and 98%. Lasalocid was found to accumulate in the liver, followed by the heart, skin/fat, kidneys, thigh muscle and gizzard. The lowest concentrations of lasalocid residues were found in the breast muscle. On day 5 of the WP, residue concentrations of lasalocid did not decline below the LOQ of the method, but were far below the maximum residue level (MRL) established for lasalocid in poultry from 20 to 100?µg kg?1 by European Commission Regulation (EU) No. 37/2010. The results confirmed that the WP established for lasalocid is sufficient to ensure the decline of its residues in the tissues of broiler chickens to the safe residue level.  相似文献   

9.
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   

10.
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   

11.
A quantitative multi-residue method that includes 13 sulfonamides, trimethoprim and dapsone was developed and validated according to Commission Decision 2002/657/EC for muscle, milk egg and honey samples. For all matrices, the same extraction procedure was used. Samples were extracted with an acetone/dichloromethane mixture and cleaned up on aromatic sulfonic acid (SO3H) SPE cartridges. After elution and concentration steps, analytes were identified and quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Data were acquired according to the multiple reaction-monitoring approach (MRM) and analytes were quantified both by the isotope dilution and the matrix-matched approaches calculating the response factors for the scanned product ions. The developed method shows good linearity, specificity, precision (repeatability and within-laboratory reproducibility), and trueness. Estimated CCβ for sulfonamides ranged between 5.6 and 8.2 µg kg?1 for eggs, between 11.1 and 69.9 µg kg?1 for milk, between 64.7 and 87.9 µg kg?1 for muscle, and between 2.7 and 5.3 µg kg?1 for honey. CCβ values for dapsone were 3.1, 0.6, 0.7 and 1.5 µg kg?1 and for trimethoprim were 3.1, 6.7, 81.7 and 3.0 µg kg?1 calculated for eggs, milk, muscle and honey, respectively. Recovery for all matrices was in the range from 89.1% and 109.7%. In matrix effect testing, no significant deviations were found between different samples of muscle and milk; however, a matrix effect was observed when testing different types of honey. The validation results demonstrate that the method is suitable for routine veterinary drug analysis and confirmation of suspect samples.  相似文献   

12.
The Explorer® 2.0 tube test is a microbial inhibition test for the screening of antimicrobial residues in food samples. The new e-Reader® device coupled to Explorer® 2.0 operates by incubation at a selected temperature, determination of the endpoint of the assay and interpretation to generate results. This system was validated for muscle samples according to the European Commission Decision 2002/657/EC. Sensitivity towards 25 substances from several groups of antimicrobials was investigated in a first step. Detection capabilities for six substances representing the six major antimicrobial groups were also determined in bovine muscle. The detection capabilities for amoxicillin (10 µg l?1), cefalexin (200 µg l?1), doxycyclin (100 µg l?1), sulfamethazine (100 µg l?1), tylosin (100 µg l?1) and neomycin (200 µg l?1) were in all cases at or below the maximum residue limit (MRL). Specificity and applicability of the test were demonstrated with muscle samples from four animal species (bovine, porcine, ovine and poultry) and results were found to be satisfactory. Ruggedness was evaluated on negative and spiked samples with sulfamethazine as a representative antimicrobial. Neither false-positives nor false-negatives were detected when varying the sample volume, the time of pre-incubation, the temperature of incubation and the batch of the test. These results prove that Explorer® 2.0 coupled to e-Reader® is a valuable tool for the screening of a broad range of antimicrobials in muscle. This new methodology simplifies the analysis and increases the accuracy of interpretation of the test results since the endpoint of the assay is automatically determined and results are interpreted objectively.  相似文献   

13.
Tissue distribution and residue depletion of metronidazole (MNZ) was studied in rainbow trout (Oncorhynchus mykiss) following oral administration of MNZ in feed at the average dose of 25 mg kg?1 body weight day?1 for 7 days at 11 ± 2°C. The MNZ concentration in feed was 0.25% while daily feed intake was 1% of body weight. The concentrations of MNZ and its main metabolite, hydroxymetronidazole (MNZOH), in fish tissues were determined by LC-MS/MS. The drug was well distributed in tissues with maximum concentrations on day 1 post-administration. At this time, the mean MNZ concentrations in muscle, skin, kidney, liver and gill were 14 999, 20 269, 15 070, 10 102 and 16 467 µg kg?1 respectively. MNZ was converted into MNZOH with the ratio of MNZOH:MNZ up to 7% in all fish tissues throughout the withdrawal period. This shows that MNZ itself is the main residue in rainbow trout. MNZ was detected at the level close to the decision limit (0.20 µg kg?1) in muscle, skin and muscle with adhering skin up to 42 days, while in kidney, liver and gill it was up to 28 days post-administration. MNZOH was eliminated more rapidly from fish tissues and it was present in muscle alone up to 21 days. The elimination half-lives of MNZ and MNZOH in rainbow trout tissues were 1.83–2.53 and 1.24–2.12 days, respectively. When muscle without skin was analysed, higher MNZ and MNZOH concentrations were detected, and for a longer period of time, than in muscle with adhering skin. Thus muscle alone could be more appropriate for the effective residue control of MNZ in rainbow trout. For the same reason, it is also essential to ensure direct cooling immediately after sampling, since MNZ and its metabolite degrade in fish muscle and skin stored in non-freezing conditions.  相似文献   

14.
Mass spectrometric methods were developed and validated for the analysis in chicken muscle of a range of antibiotic growth promoters: spiramycin, tylosin, virginiamycin and bacitracin, and separately for two marker metabolites of carbadox (quinoxaline-2-carboxylic acid and 1,4-bisdesoxycarbadox), and a marker metabolite of olaquindox (3-methyl-quinoxaline-2-carboxylic acid). The use of these compounds as antibiotic growth promoters has been banned by the European Commission. This study aimed to develop methods to detect their residues in muscle samples as a means of checking for the use of these drugs during the rearing of broiler chickens. When fed growth-promoting doses for 6 days, spiramycin (31.4?µg?kg?1), tylosin (1.0?µg?kg?1), QCA (6.5?µg?kg?1), DCBX (71.2?µg?kg?1) and MQCA (0.2?µg?kg?1) could be detected in the muscle 0 days after the withdrawal of fortified feed. Only spiramycin could consistently be detected beyond a withdrawal period of 1?day. All analytes showed stability to a commercial cooking process, therefore raw or cooked muscle could be used for monitoring purposes.  相似文献   

15.
Maduramycin is a polyether ionophoric coccidiostat used to prevent coccidiosis in poultry at a prescribed concentration over a certain time interval. Due to public health concerns about the presence of coccidiostat residues in poultry, the aim of the present study was to determine the level of maduramycin residues in the tissues of broiler chickens fed commercially produced feed containing 5 mg kg?1 of maduramycin in complete feed throughout the 5-day withdrawal period (WP). The residues were investigated by liquid chromatography (LC) coupled with electrospray ionisation (ESI) tandem mass spectrometry (MS/MS). The limit of detection (LOD) and limit of quantification (LOQ) of the method were 0.3 and 0.8 µg kg?1, respectively. The average recovery based on matrix-fortified calibrations for chicken tissues was 90%. Maduramycin was found to be rapidly distributed in all tissues. The highest concentrations of maduramycin residues were found in the heart followed by the skin, liver, gizzard, kidneys and, finally, muscle (thigh and breast). On day 5 of the WP, residue concentrations of maduramycin did not decline below the LOQ of the method. Our results emphasize the need to establish a maximum residue limit (MRL) for maduramycin to control its residue levels in edible tissues from chickens before slaughter.  相似文献   

16.
During 2012–2014, 170 samples of export quality raisins were collected from different vendors in Pakistan. The collected samples were analysed for the presence of aflatoxins (AFs) and Ochratoxin A (OTA) contamination using high-performance liquid chromatography technique. The limit of detection and limit of quantification of AFs/OTA were 0.12/0.10 and 0.36/0.30 µg kg?1, respectively. Only 5% of the samples were contaminated with AFs, ranging 0.15–2.58 µg kg?1 with a mean of 0.05 ± 0.26 µg kg?1. None of the raisin samples exhibited AFs contamination above the maximum limit (ML = 4 µg kg?1) as set by the European Union (EU). About 72% of the samples were contaminated with OTA, ranging 0.14–12.75 µg kg?1 with a mean of 2.10 ± 1.9 µg kg?1. However, in 95.3% of the tested samples, OTA level was lower than the ML of 10 µg kg?1 as regulated by the EU. Apparently, a strict and continuous monitoring plan, including regulatory limits, improves food safety and quality for all types of commodities.  相似文献   

17.
Two surveys are presented of straw analysed for naturally occurring chloramphenicol (CAP), a drug banned for use in food-producing animals. In the first study, CAP was analysed by LC-MS/MS and detected in 37 out of 105 straw samples originating from the Netherlands, France, the UK, Germany and Denmark. The highest level found was 6.3 µg kg?1, the average 0.6 µg kg?1 and the median 0.2 µg kg?1. The second study included a method comparison between ELISA and LC-MS/MS and a survey of CAP in cereal straw sampled at farms in all areas of Sweden. A total of 215 samples were screened by ELISA and a subset of 26 samples was also analysed by LC-MS/MS. Fifty-four of the samples contained more than 1 µg kg?1 CAP and the highest level found was 32 µg kg?1 (confirmed by LC-MS/MS). The highest contents of CAP in this study were allocated to the Baltic sea coast in the south-eastern part of Sweden (the county of Skåne and the Baltic Sea isle of Gotland). These results indicate a high incidence of CAP in straw in north-west Europe and have a severe impact on the enforcement of European Union legislation.  相似文献   

18.
A method is reported for the analysis of sterigmatocystin in various food and feed matrices using a commercial sterigmatocystin immunoaffinity column (IAC) for sample clean-up prior to HPLC analysis by UV with mass spectrometric detection (LC-MS/MS). Cereals (wheat, oats, rye, maize and rice), sunflower seeds and animal feed were spiked with sterigmatocystin at levels from 0.75 to 50 µg kg?1 to establish method performance. Using acetonitrile/water extraction followed by IAC clean-up, and analysis by HPLC with detection at 325 nm, recoveries ranged from 68% to 106%, with repeatability from 4.2% to 17.5%. The limit of quantification with UV detection in these matrices was 1.5 µg kg?1. For the analysis of beer and cheese the sample preparation prior to IAC clean-up was changed to accommodate the different properties of the matrix, prior to analysis by LC-MS/MS. For beer and cheese spiked at 5.0 µg kg?1 the recoveries were 94% and 104%, and precision (RSDs) were 1.9% and 2.9% respectively. The limits of quantification by LC-MS/MS in beer and cheese were 0.02 and 0.6 µg kg?1 respectively. The sterigmatocystin IAC was demonstrated to provide an efficient clean-up of various matrices to enable this mycotoxin to be determined by either HPLC with UV detection or LC-MS/MS.  相似文献   

19.
In 2011, the European Union prohibited the production of polycarbonate (PC) baby bottles due to the toxic effects of the PC monomer bisphenol-A. Therefore, baby bottles made of alternative materials, e.g. polypropylene (PP) or polyethersulphone (PES), are currently marketed. The principal aim of the study was the identification of major compounds migrating from baby bottles using a liquid–liquid extraction followed by GC/MS analysis. A 50% EtOH in water solution was selected as a simulant for milk. After sterilisation of the bottle, three migration experiments were performed during 2 h at 70°C. A non-targeted liquid–liquid extraction with ethyl acetate–n-hexane (1:1) was performed on the simulant samples. Identification of migrants from 24 baby bottles was done using commercially available WILEY and NIST mass spectra libraries. Differences in the migrating compounds and their intensities were observed between the different types of plastics, but also between the same polymer from a different producer. Differences in the migration patterns were perceived as well between the sterilisation and the migrations and within the different migrations. Silicone, Tritan? and PP exhibited a wide variety of migrating compounds, whereas PES and polyamide (PA) showed a lower amount of migrants, though sometimes in relatively large concentrations (azacyclotridecan-2-one up to 250 µg kg?1). Alkanes (especially in PP bottles), phthalates (dibutylphthalate in one PP bottle (±40 µg kg?1) and one silicone bottle (±25 µg kg?1); diisobutylphthalate in one PP (±10 µg kg?1), silicone (up to ±80 µg kg?1); and Tritan? bottle (±30 µg kg?1)), antioxidants (Irgafos 168, degradation products of Irganox 1010 and Irganox 1076), etc. were detected for PP, silicone and Tritan? bottles. Although the concentrations were relatively low, some compounds not authorised by European Union Regulation No. 10/2011, such as 2,4-di-tert-butylphenol (10–100 µg kg?1) or 2-butoxyethyl acetate (about 300 µg kg?1) were detected. Migrating chemicals were identified as confirmed (using a standard) or as tentative (further confirmation required).  相似文献   

20.
The presence of ochratoxin A (OTA) was determined in traditional dry-cured meat products made from sub-chronically OTA-exposed pigs. The experimental group of pigs (n = 5) was treated with 300 µg OTA kg–1 of feed during 30 days, whereas the control group (n = 5) remained untreated. After the household production of six types of dry-cured meat products based on traditional recipes, OTA residues were determined in final products produced from each treated and untreated animal using an immunoenzymatic technique (ELISA) and HPLC with fluorescence detection (HPLC-FD). The analytical methods showed acceptable analytical performance results and high correlation coefficients. Mean OTA concentrations ranged from 4.51 ± 0.11 µg kg–1 in smoked ham to 6.87 ± 2.01 µg kg–1 in home-made Slavonian sausage. The study demonstrated that pig exposure to OTA leads to the accumulation of OTA residues in muscle and adipose tissue used for the production, and consequently results in contamination of the final meat products.  相似文献   

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