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1.
The aim of this research was to determine total mercury (Hg) content in 69 canned tuna of 13 brands marketed in southwest Brazil. All values are reported in μg.g−1 wet weight basis. Potential health risk was estimated on the basis of mercury concentration and average consumption (175 g/per week) of fish in Brazil comparing to PTWI of 1.6 μg.kg−1 (FAO/WHO, 2010). A large variation in the concentration of mercury in different species was observed. Mean mercury concentration was 0.256 ± 0.215 μg.g−1 with a highest value of 1.060 μg.g−1 in a single can. In general average concentration was below the legislation of 1.0 μg.g−1 for predatory species (BRASIL, 2010). Estimate weekly intake (EWI) varied 0.2–1.7 μg.kg−1. For the analyzed brands and Brazilian fish consumption, no human health risk is likely to occur. However one brand was higher than PTWI of 1.6 μg.kg−1 showing no safety for specific risk group. Further studies including specific data on canned tuna consumption in specific populations will be needed as well as the fish type, fish size and fishing location.  相似文献   

2.
A study was performed to evaluate the risk regarding the presence of nickel in commercial premade baby foods: 26 ready meals, 31 fruits, 8 deserts and 20 paps. The analytical methodology used for the determination of nickel was dry ashing followed by graphite furnace atomic absorption spectrometry. Method detection limit (12.5 μg kg−1) was obtained through a matrix matched calibration curve, using a nickel free commercial ready meal (meat).The results showed that 78 (91.8 %) samples contained nickel, with values up to 225.7 μg kg−1. The group with the highest average concentration was the fruits (50.1 μg kg−1) followed by the ready meals (40.2 μg kg−1). Samples from organic farming presented higher detection frequency and average concentration (54.7 μg kg−1) than the others. Using the average results, the tolerable daily intake proposed by EFSA (2.8 μg kg−1 b.w.) was surpassed for the 2 year old age group, with daily ingestions up to 3.1 μg kg−1 b.w.. This results highlight the risk promoted by the nickel present in commercial premade baby food.  相似文献   

3.
Species-specific isotope dilution inductively coupled plasma mass spectrometry (SS ID ICP-MS) and high-performance liquid chromatography (HPLC) were used to obtain accurate and SI traceable results for methyl mercury in seafood samples such as clam, oyster and fish homogenate. The mass fractions of (62.3 ± 2.3) μg kg−1, (5.44 ± 0.36) μg kg−1 and (531 ± 19) μg kg−1 were obtained for MeHg (as Hg) in IAEA-461, IAEA-470 and IAEA-476, respectively. Direct isotope dilution mass spectrometry was performed for total mercury content then the content of inorganic mercury in selected samples was obtained by calculation. It was found that the content of inorganic Hg in IAEA-461, IAEA-470, and IAEA-476 was as: 328 μg kg−1, 16 μg kg−1, and 62 μg kg−1, respectively. Mathematical modelling of analytical procedure and evaluation of all parameters influencing final results were adequate for validation of measurement procedure, establishing traceability and estimating expanded uncertainty. Developed procedures were successfully applied in the characterization process of fish homogenate candidate reference material and in the calculation of assigned values in the frame of IAEA-476 inter-laboratory comparison study. Compatibility between obtained results and those derived from the certification campaign, organized by International Atomic Energy Agency on the same sample matrix (<2.6 % difference) further validated performed ID ICP-MS protocols.  相似文献   

4.
The minerals content of 36 dried figs samples collected from three Mediterranean areas in 2018 was presented in this study. The aim of this research was to evaluate whether the mineral elements amounts were significantly different among the production regions. Samples grown in Italy, Greece and Turkey were analyzed in this study. Samples were found to be a good source of potassium (average content between 3.5 ± 0.2 g kg−1 and 8.12 ± 0.88 g kg−1), calcium (between 1.46 ± 0.24 g kg−1 and 4.49 ± 0.28 g kg−1), magnesium (between 0.84 ± 0.04 g kg−1 and 1.28 ± 0.15 g kg−1), and sodium (between 0.45 ± 0.04 g kg−1 and 0.70 ± 0.11 g kg−1). Cadmium ad lead concentrations were always below the regulated values and below the quantification limit in all Italian samples, whereas chromium was detected in all samples from Greece (0.05 ± 0.01 mg kg−1) and Turkey (0.03 ± 0.01 mg kg−1), and in 65 % of samples from Italy (0.08 ± 0.02 mg kg−1). Results confirm the good figs quality related to their essential trace elements content and they highlight the safety of these food products correlated to the intake of toxic elements. Furthermore, statistical analysis of the results pointed out that the mineral elements amount is significantly different among the three sample groups, hence it is possible to discriminate figs according to their geographical origin by PCA.  相似文献   

5.
Anthropogenic agronomic practices could negatively affect the agricultural soil which is the main source for inorganic arsenic (i-As) contamination in rice fields due to flooding. The presence of essential elements could be impacted by food industry units operations. The aim of this study was to evaluate the effect of husking and polishing on mineral essential elements and inorganic As species in rice from Protected Natural Reserve “Marjal de Pego-Oliva”. The amount of all studied elements was significantly affected by husking (a decrease of Ca, Na and Pb, 360 to 101 mg kg−1, 202 to 46.9 mg kg-1 and 17.9 to 5.70 μg kg−1, respectively) and by polishing (a reduction of Na, Mg, P, K, Ca and Cu, 46.9–26.8 mg kg−1, 1600 to 481 mg kg−1, 4050 to 1530 mg kg−1, 2780 to 882 mg kg−1, 101 to 53.7 mg kg−1, and 3600 to 2840, μg kg−1, respectively).The replacement of white rice (WR) to brown rice (BR) could enhance the daily dietary intake of essential elements to reach the dietary reference values and the maximum i-As (40.9 and 44.9 i-As μg kg-1 for BR and WR, respectively) was below the maximum level recently established by European Food Safety Agency.  相似文献   

6.
Inorganic As (iAs) species require strict monitoring in foodstuff due to their toxicity. Rice is of particular concern, with recent legislations establishing limits for these species. In this work we develop a method based on selective hydride generation atomic absorption spectrometry (HGAAS) for the determination of iAs in different types of rice (polish, parboiled, brown and paddy rice). The multivariate design of experiments used for optimization showed interactions between different factors involved in hydride generation. Matrix effects were systematically studied, where the flow rate of the carrier gas proved to be a critical parameter for the minimization of matrix interferences. Nevertheless, matrix-matching was found to be necessary for accurate quantification of paddy rice samples. Comparison of the iAs concentrations obtained by HGAAS and HPLC-ICP-MS showed non-significant differences between the methods. Analysis of 86 rice samples from the province of Entre Ríos showed relatively low concentrations of iAs (<282 μg kg−1 for paddy rice and <120 μg kg−1 for polished rice), regardless of total As concentrations (which ranged from 63 μg kg−1 to 932 μg kg−1), suggesting that the rice analyzed tends to accumulate As in its organic forms.  相似文献   

7.
The use of the same batch of oil for deep-frying on several occasions is a common practice. This study sought to determine the effects of repeated frying cycles on the composition, concentrations and risk of polycyclic aromatic hydrocarbons (PAHs) in six types of vegetable oils and the samples of fish fried therein. The PAH concentrations in the oils were measured before use and after each of three successive cycles of frying. Fish was fried at each time of use of the oils and, also, monitored for their PAH content. The PAH content in all samples was determined by gas chromatography-mass spectrometry (GC–MS). The concentrations of Ʃ22 PAHs in the unused oils ranged from 43.3–2107 μg kg−1, while those in the used oil ranged from 40.8–4090 μg kg−1. There were significant changes (p < 0.05) in the concentrations and composition of PAHs with respect to vegetable oil types and number of frying cycles. The cancer risk values for the vegetable oils (10−4 to 10−5) after three frying cycles exceeded the acceptable risk value of 10-6 indicating a probable lifetime carcinogenic risk. However, adverse non-carcinogenic risks through consumption of these oils and fried fish were low.  相似文献   

8.
The free amino acid composition and biogenic amine content were analysed in pasteurised goat milk cheeses produced in different regions in Spain. These goat cheeses are made with pasteurised milk to which a mesophilic starter culture is added; they are enzymatically coagulated, uncooked, pressed cheeses. They have a firm texture with a slight but typical goat milk aroma and flavour. The total free amino acids varied markedly among the samples, ranging from 1400 to 28,000 mg kg−1 DM (dry matter). Of the 20 amino acids analysed, the most abundant were leucine, proline, valine, glutamic acid, lysine, glutamine, ornithine and γ-aminobutyric acid, which accounted for over 60% of the total free amino acids. The goat milk cheeses presented low concentrations of biogenic amines, the most abundant being tyramine and/or histamine, with values ranging from 4.2 to 50.7 and from 10.2 to 60.5 mg kg−1 DM, respectively. Total biogenic amine content ranged between 26.4 mg kg−1 DM and 175.1 mg kg−1 DM, and was always below the level that is considered dangerous for humans. Therefore, taking into consideration the concentrations of BAs, these goat milk cheeses, produced under good hygienic conditions, can be considered safe for consumers.  相似文献   

9.
Maize flour is a food rich in nutrients important for the proper functioning of the human body. Nevertheless, for the determination of metals in maize flour there are few studies, which raise concern about quality and its mineral composition for consumption. In this work, it was evaluated the concentration of essential (Ca, Cu, Fe, Mn, Mg, Cr and Zn) and non-essential (Cd and Cr) metals in yellow and white maize flour samples produced in Paraná State - Brazil. For this purpose, it was performed a sample treatment employing wet digestion in a digester block and determination of metals by atomic absorption spectrometry (AAS). The highest concentrations found in the flour were Ca (55.4 mg kg−1) and Mg (86.9 mg kg−1) and the lowest concentrations were Cr (0.11 mg kg−1) and Cd (0.01 mg kg−1). In yellow and white maize flour the highest concentration was for Mg, 81.5 mg kg−1and 98.4 mg kg−1, respectively. Principal component analysis (PCA) showed that some samples had a similar mineral profile, such as the relationship with the place of origin of the cereal.  相似文献   

10.
Total (Ast), inorganic arsenic (Asi = As(III) + As(V)) and dimethylarsonic acid (DMA) were determined in 37 commercial rice samples collected in France. Ast was measured by inductively coupled plasma-mass spectrometry (ICP-MS) whereas anion-exchange chromatography – ICP-MS was used for Asi and DMA determination. Ast in raw rice varied from 0.041 to 0.535 mg kg−1 whereas Asi varied from 0.025 mg kg−1 (polished Basmati rice) up to 0.471 mg kg−1 (organic rice duo). The daily intake and associated health risk for different population groups as a function of age and gender was also assessed. The intake varied between 0.002 and 0.184 μg kg−1 body weight for Ast and 0.002 and 0.153 μg kg−1 body weight for Asi, which do not pose a chronic toxicity risk. Organic wholegrain rice may entail a risk for children in the case of sole consumption at the expense of polished rice. The impact of rice cooking/boiling in terms of the overall toxicological risk related to As species was also investigated. Pre-rinsing and boiling the raw rice by using an excess of water is the most efficient mode to obtain a significant Asi removal and further reduction of the toxicological risk for children, particularly for white rice varieties.  相似文献   

11.
We have established a novel hydrophilic chromatography (HILIC)-high performance liquid chromatography (HPLC) method to assess sialic acid content in food products. Single-factor and response surface methodologies (RSM) were used to systematically optimize the hydrolysis conditions of the food samples to extract the maximum amount of sialic acid. Chromatographic conditions were also adjusted. In foods containing sialic acid, we observed a strong linear relationship between sialic acid and peak area, ranging from 5 to 100 μg/mL (R2 = 0.9998). The lowest detectable sialic acid concentration (RSN = 3) was 0.2 μg mL−1, and the method detection limit was 0.02mg kg−1. Sample recovery ranged from 95.85% to 99.78%, with an RSD of 1.46% (n = 6). Thus, the described method can be applied to the study of sialic acid content in foods.  相似文献   

12.
Fourteen patients with mild to moderate catabolism due to accidental or surgical trauma and eight neoplastic patients were treated with early, short term TPN immediately after injury or surgery. Patients were given nitrogen, 0.35 g kg−1 day−1 and glucose, 35 kcal kg−1 day−1. The plasma amino-acid patterns during treatment and after its discontinuation were investigated and appeared to be predominantly determined by the composition of the administered amino acid solution.When the treatment was stopped the plasma concentration of the infused amino acids and of Ornithine (not administered) fell towards the initial values. The time needed to reach the pretreatment plasma concentration depended on the amino-acid solution used and varied between 3 and 6 h for different amino acids. When investigating plasma amino-acid concentration this time delay should be accounted to differentiate the effect of TPN and of the underlying pathology.  相似文献   

13.
A simple and sensitive method for the simultaneous determination of glyoxal and methylglyoxal in alcoholic beverages and fermented foods was developed. This method involved simultaneous derivatization in solution with 2,2,2-trifluoroethyl hydrazine (TFEH) and headspace solid phase microextraction, followed by detection via gas chromatography-mass spectrometry (GC–MS). The method established herein can be summarized as follows. The sample was adjusted to pH 6.0 in a headspace vial, saturated with sodium chloride, and allowed to react with TFEH at 85 °C for 20 min. The formed derivatives were vaporized and adsorbed on divinylbenzene/carboxy/polydimethylsiloxane fibers. The TFEH derivatives were subsequently desorbed and analyzed by GC–MS, where the spectrum showed a single sharp peak. Under the established conditions, the quantification limits of glyoxal and methylglyoxal were 3.6 and 2.1 μg kg−1, respectively, and the relative standard deviations were under 8% at concentrations of 20, 100 and 2000 μg kg−1. All samples were detectable at typical glyoxal (62–4116 μg kg−1) and methylglyoxal (11–2342 μg kg−1) concentrations in beverages and foods.  相似文献   

14.
Thinning consists of reducing fruit load at immature stage and thus allowing remaining fruits to develop to their maximum size and quality. The waste material produced during this farming practice was characterised in 9 pomegranate cultivars, by evaluating: weight, size, maturity index, pH, organic acids and sugars profiles, contents of minerals, punicalagin, and ellagic acid, total polyphenols and antioxidant activity. Citric and quinic were the main organic acids. Potassium was the predominant mineral, reaching up to 11 g kg−1 dry weight (dw). Total polyphenol content ranged from 777 to 1660 g GAE kg−1 dw, α-punicalagin from 101 to 195 and β-punicalagin from 80.1 to 111 g kg−1 dw. The antioxidant activity was assessed by three methods and its values varied from 2923 to 4486 for ABTS, from 3153 to 4685 for FRAP, and from 2075 to 2934 mmol Trolox kg−1 dw for DPPH. Pomegranate thinning fruits, especially sour-sweet cultivars, are rich in bioactive compounds, with a potential use in the food, chemical and pharmaceutical industries.  相似文献   

15.
A number of wild, edible mushroom species (Baorangia bicolor, Boletus calopus, Boletus obsclereumbrinus, Butyriboletus roseoflavus, Rubroboletus sinicus, Rugiboletus extremiorientalis and Xerocomus sp.) were collected in 2017, from Yunnan (Yuxi prefecture) in SW China. Samples of raw and stir-fried pools of these specimens were analysed for radioisotopes 137Cs (caesium) and 40K (potassium), and for total K concentrations. On a whole (wet) weight (ww) basis, 137Cs activity ranged from < 0.10 to 0.75 Bq kg−1 for raw, and from 0.5 to 4.4 Bq kg-1 in stir-fried mushrooms. Radiopotassium (40K) activity ranged from 57 to 96 Bq kg−1 ww for raw, and 170 to 370 Bq kg−1 ww for stir-fried mushrooms, while the corresponding concentration ranges for total K were 2100–3400 mg kg−1 ww (mean: 2800 ± 3900 mg kg−1 ww), and 6000–13000 mg kg−1 ww-(mean: 8700 ± 2100 mg kg−1 ww), respectively. This data indicates that mushrooms from this region show negligible 137Cs contamination with evidently higher activity levels of 40K. The deep oil stir-frying process results in enrichment in the resulting meals for all three determinants. 100 g meal portions showed 137Cs activity in the range < 0.08 to 0.44 Bq 100 g−1 ww (mean 0.15 ± 0.12 Bq 100 g−1 ww), and 40K activity from 16 to 37 Bq 100 g−1 ww (mean 24 ± 6 Bq 100 g−1 ww). The consequent exposure from 40K contained in a single 100 g serving and weekly (100 g x7) servings was equivalent to radiation doses in the range of 0.099 to 0.23 μSv and 0.68–1.6 μSv per capita (means 0.15 ± 0.04 and 1.1 ± 0.3 μSv). This is equivalent to doses in the range of 0.0017 to 0.0038 μSv kg-1 bm day-1 and 0.011 to 0.027 μSv kg-1 bm week-1 respectively (mean values of 0.0025 ± 0.006 μSv kg-1 bm day-1and 0.018 ± 0.004 μSv kg-1 bm week-1). Analogically to the annual 137Cs radiation exposure resulting from high rates of annual consumption (20–24 kg per capita), the estimated annual dose of radiation from 40K would range from 0.34 up to 0.92 μSv kg-1 bm (mean 0.60 μSv kg-1 bm). Thus in practice, high annual consumption rates of wild, stir-fried mushrooms as seen in Yunnan, would result in negligible internal doses from decay of artificial 137Cs, relative to that from natural 40K. The 100 g servings also contained between 590–1300 mg K making this local food one of the top dietary sources of nutritionally important potassium for local consumers.  相似文献   

16.
Rice and its derivatives are important source of essential and non-essential elements. Essential elements as cobalt (Co) and selenium (Se) are vital for human homeostasis. However, non-essential elements such as arsenic (As), cadmium (Cd) and lead (Pb) may be present in rice-based food and consequently, people can be exposed—especially children and the celiac population. This study aimed to determine essentials and non-essentials elements in rice-based products and baby food and also to evaluate nutritional risk by estimating the daily intake of non-essential elements. Regarding essential elements, Co and Se presented the highest concentrations in rice flour (56 μg kg−1) and porridge (254 μg kg−1), respectively. For non-essential elements, the highest concentrations of As, Cd and Pb were 104 μg kg−1 (porridge), 16 μg kg−1 (flour), and 188 μg kg−1 (bread), respectively. Total As concentration in Brazilian rice-based baby food was <29 μg kg−1. However, As-speciation revealed inorganic-As (i-As) as the main specie. The highest estimated daily intake of Cd, Pb and i-As were 1.37 (rice-based baby food); 10.39 (pasta); and 3.34 (pasta) μg d−1, respectively. Therefore, continuous food monitoring for nutritional and toxicological purpose is necessary, especially concerning these particular populations and discussions for maximum levels of non-essential elements.  相似文献   

17.
This study evaluates the nutritional potential of Sarcocornia ambigua as new a source of minerals. The mineral concentrations of two different growing populations (natural occurrence and irrigated) of S. ambigua were evaluated using inductively coupled plasma mass spectrometry. In all samples, the mineral present in highest amounts was potassium (K) (19–24 μg g−1), followed by magnesium (Mg) (8.6–14 μg g−1) and then calcium (Ca) (2.6–4.0 μg g−1). In addition, in vitro bioacessibility assay demonstrated that very high fraction (65–80%) of these K and Mg (80 and 65%) of total concentration of these elements is bioacessible from S. ambigua analyzed. The trace elements vanadium (V), chromium (Cr), cobalt (Co), copper (Cu) and lithium (Li) have more than above 50% of total concentration was found bioaccessible. In all cases, mass balance was verified by carrying out the total digestion of the remaining residue and the relationship between total concentration and bioaccessibility. The data related to the concentrations and the bioaccessible fractions of the minerals provide a starting point for more complex and in-depth evaluations from the nutritional point of view, including the establishment of a recommended daily dietary intake for this plant.  相似文献   

18.
Selenium (Se) is an essential trace element for human health and plays an important role in fundamental physiological functions. Se accumulates in sesame seeds and this situation may differ between genotypes. Determination of Se content in food is very important because there is a narrow margin of safety between an adequate amount and overconsumption. The purpose of this study was to evaluate the variability in Se content among different sesame accessions from Turkey (12 sesame accessions) and 22 other countries from four continents (Asia, Africa, Europe and America). The determination of total Se in seed was performed with an atomic absorption spectrometer. The Se content of sesame seeds samples exhibited a wide range i.e. 0–9.32 mg kg−1, with an average value of about 2.29 mg kg−1. The accession India 1 had the highest Se concentration. The mean Se contents of sesame from 23 countries varied between 0.24–8.31 mg kg−1 and with an average value of about 2.29 mg kg−1. Sesame breeders can use the results of the present study to further the breeding programs for the development of new biofortified varieties.  相似文献   

19.
Different honey types were collected in Croatia during 2010 and 2011: 7 multifloral orchard honeys, 7 multifloral meadow honeys, 19 black locust, 9 chestnut, 11 lime and 6 sage honeys. Elements were measured using graphite (As, Cu, Cd, Pb, Se) and flame atomic absorption spectrometer (Ca, Fe, K, Mg, Na, Zn) and by mercury analyser (Hg). Significant differences in Ca, Fe, K, Mg, Zn, As and Hg levels were observed between honey types. In chestnut honey were determined (K, Ca, Mg: mg kg−1; Hg, Ad, Cd: μg kg−1): the highest concentrations of K 2824.4, Ca 486.7, Mg 59.1 and Hg 2.52; the lowest of As 24.1 and Cd 2.52. Lime honey has been shown the highest content of Cu (20.6 mg kg−1), Zn (6.78 mg kg−1), Cd (2.14 μg kg−1) and Pb (810.3 μg kg−1). The lowest levels of following elements were determined in black locust honey (Fe, K, Mg: mg kg−1; Hg: μg kg−1): Fe 2.77, K 304.7, Mg 8.02 and Hg 0.82. Sage honey had the lowest Ca and Na content (173.9 and 31.8 mg kg−1). Among the multifloral honeys, the following was determined (Fe, Na, Cu: mg kg−1; As, Pb: μg kg−1): orchard honey – highest of Fe 5.17 and As 276.1, lowest Pb 301; meadow honey – highest Na 36.1, lowest Cu 4.38. The average Ca, Cu and Pb levels found in multifloral honey types were much higher than those reported in other European countries. Calcium levels in lime, chestnut and black locust were higher than those from other countries.  相似文献   

20.
A new, sensitive, and safe pretreatment method for the analysis of Cd(II) and Zn(II) ions in oil samples prior to flame atomic absorption spectrometry was developed. For the first time, a deep eutectic solvent is used as a disperser in reversed-phase dispersive liquid-liquid microextraction procedure. For this purpose, a deep eutectic solvent with low viscosity and miscible with both aqueous and organic phases is prepared by mixing glycolic acid and mandelic acid at a molar ratio of 2:1. The variables involved in this process were studied to provide high enrichment factors. Under optimized conditions, the linear ranges of calibration curves for Cd(II) and Zn(II) ions were obtained 0.30−20 and 0.50−30 μg L−1, respectively. The obtained detection limits and enrichment factors were 0.12 and 0.18 μg L−1; and 32.7 and 32.2 for Cd(II) and Zn(II), respectively. Repeatability of the proposed method, expressed as relative standard deviation, ranged from 2.7 to 4.1 % (n = 6, C = 1 μg L−1 of each cation). Finally, the proposed method was successfully applied for the determination of Cd(II) and Zn(II) concentrations in various oil samples.  相似文献   

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