首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
Heavy metals (As, Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn) in various vegetables (cabbage, green onion, lettuce, parsley, rocket, spinach, carrot, onion, potato and cauliflower) from the market in Jordan were measured using inductively coupled plasma-mass spectrometry. As, Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn ranged from 0.009–0.275 mg kg?1 wet weight, 0.004–0.060 mg kg?1, 0.003–0.401 mg kg?1, 0.105–3.51 mg kg?1, 0.15–1.15 mg kg?1, 0.93–14.39 mg kg?1, 0.044–0.702 mg kg?1, 0.072–0.289 mg kg?1 and 2.23–6.65 mg kg?1, respectively. Parsley, followed by spinach, contained the highest concentration of heavy metals. Onion contained high levels of toxic heavy metals. The content of Cu in parsley and spinach and Pb in onion exceeded the Codex limits. However, the daily intake of heavy metals from the tested vegetables was lower than the maximum limits for allowable intake.  相似文献   

2.
BACKGROUND: In this study, the activity concentrations of 232Th, 238U, 40K and 137Cs were measured in tea, cabbage, orange, kiwi and soil samples collected from different stations using gamma spectrometry with a high‐purity germanium detector. RESULTS: The average activity concentrations of 232Th, 238U, 40K and 137Cs were found to be 8.2 ± 1.8, 17.3 ± 3.3, 465.8 ± 11.8 and 20.9 ± 3.8 Bq kg?1 in food samples, and 72.4 ± 9.8, 51.1 ± 8.3, 229.3 ± 14.7 and 312.9 ± 11.5 Bq kg?1 in farm soils, respectively. The internal effective dose to individuals and excess lifetime cancer risk from the consumption of the food type radioactivity ranged between 11.7 and 53.6 µSv y?1 and between 0.05 × 10?3 and 0.24 × 10?3, respectively. The annual external gamma effective dose and excess lifetime cancer risk in the farms due to soil radioactivity ranged between 94.1 and 139.8 µSv y?1 and between 0.43 × 10?3 and 0.64 × 10?3, respectively. The mean transfer factors of 232Th, 238U, 40K and 137Cs, from the soil to vegetables and fruit were 0.57, 0.32, 2.12 and 0.04, respectively. CONCLUSION: Annual effective gamma doses were found to be higher than the world's average in soil samples. The excess lifetime cancer risks were only found higher than the world's average in soil samples. Copyright © 2011 Society of Chemical Industry  相似文献   

3.
Potatoes are a basic component of human diets worldwide being an excellent source of minerals linked the maintenance of health. Contents of calcium (Ca), magnesium (Mg), potassium (K), sodium (Na), cupper (Cu), iron (Fe), manganese (Mn), zinc (Zn), nickel (Ni) and chromium (Cr) in seventy‐four fresh potato samples from different varieties consumed in Tenerife Island (Canary Islands, Spain) were determined by flame atomic absorption spetrometry (FAAS). The mean concentrations were 60.1 mg kg?1, 222 mg kg?1, 5047 mg kg?1, 125 mg kg?1, 1.69 mg kg?1, 8 mg kg?1, 1.70 mg kg?1, 3.88 mg kg?1, 62.7 μg kg?1 and 19.9 μg kg?1 for Ca, Mg, K, Na, Cu, Fe, Mn, Zn, Ni and Cr, respectively. The varieties of local potatoes presented higher mineral contents than imported potatoes. Potassium presented the highest contents in all varieties of potatoes. Iron was the most abundant microelement. Local potatoes offer greater nutritional contributions to the recommended intakes than imported varieties. Within the macrominerals, the highest contribution to the intakes was observed for K, while Fe was the trace element with the largest contribution to the proposed intake.  相似文献   

4.
BACKGROUND: Minerals are essential for human nutrition and must be obtained from our diet. Crucifer vegetables are a good source of these nutrients. Our objectives were to determine the genetic variability for mineral content and to evaluate the use of near‐infrared reflectance spectroscopy (NIRS) for prediction of ashes and minerals among and within the rocket species Eruca vesicaria subsp. sativa and vesicaria. The minerals studied were iron (Fe), copper (Cu), sodium (Na), potassium (K), calcium (Ca), magnesium (Mg), manganese (Mn) and zinc (Zn). RESULTS: The maximum mean values obtained for all the accessions (mean ± SE) were 235.5 ± 1.5 mg ashes kg?1, 273.3 ± 4.2 mg Fe kg?1, 18.1 ± 0.4 mg Cu kg?1, 2.8 ± 0.1 g Na kg?1, 71.6 ± 1.0 g K kg?1, 64.6 ± 1.2 g Ca kg?1, 6.8 ± 0.1 g mg kg?1, 101.6 ± 1.2 mg Mn kg?1, and 67.1 ± 0.4 mg Zn kg?1 of dry weight. CONCLUSION: The statistical analysis showed significant differences for all the minerals, except Ca, for each accession studied individually and for accessions grouped within countries. The results indicate that NIRS can be used as a rapid screening method for determining total mineral, Fe, Na, K, and Zn in rocket. Copyright © 2011 Society of Chemical Industry  相似文献   

5.
The nitrate and nitrite content of leaf vegetables (Swiss chard, sea beet, spinach and cabbage), “inflorescence” vegetables (cauliflower) and fruit vegetables (eggplant and vegetable marrow) grown with organic fertilizers have been determined by a modified cadmium–Griess method. Samples were purchased from organic food stores as well as collected directly from an organic farm in Madrid (Spain). Nitrate levels were much higher in the leaf vegetables (especially Swiss chard species; average over the different samples and species of 2778.6 ± 1474.7 mg kg? 1) than in inflorescence or fruit products (mean values between 50.2 ± 52.6 and 183.9 ± 233.6 mg kg? 1). Following Swiss chard species, spinach (1349.8 ± 1045.5 mg kg? 1) showed the highest nitrate content, and nitrite was found above the limit of detection in some samples only (spinach, 4.6 ± 1.0 mg kg? 1; sea beet, 4.2 ± 0.7 mg kg? 1 and Swiss chard, 1.2 ± 0.4 mg kg? 1). Some vegetables (spinach, cabbage and eggplant) had lower nitrate content in the samples harvested in summer, showing the influence of climatic conditions on the nitrate levels in a plant. The samples taken directly from the organic farm, with the exception of eggplant, had higher or slightly higher average nitrate values than samples purchased in the organic food stores, ranging from 117 to 1077%.  相似文献   

6.
Concentrations of mercury (Hg) in swordfish (Xiphias gladius) present a food safety problem for many countries. This study analyses total Hg (t-Hg) concentrations in 27 samples of swordfish marketed in Spain in 2005 and in their bioaccessible fractions (soluble concentration in gastrointestinal medium), obtained after applying an in vitro digestion method. Methylmercury (MeHg) was also determined in the bioaccessible fractions. t-Hg concentrations in the samples were 0.41–2.11 mg kg?1 wet weight, with a mean of 0.96 ± 0.47 mg kg?1 wet weight. A total of 37% of the samples exceeded the Hg limit set by Spanish legislation (1.0 mg kg?1 wet weight). Bioaccessible t-Hg concentrations were 0.17–1.72 mg kg?1 wet weight (0.63 ± 0.4 mg kg?1 wet weight), corresponding to 38–83% (64% ± 14%) of t-Hg. Bioaccessible MeHg concentrations, representing 94% of the bioaccessible t-Hg concentrations, were 0.16–1.53 mg kg?1 wet weight, with a mean of 0.49 ± 0.32 mg kg?1 wet weight. Children and adults who regularly consume this product in Spain have Hg and MeHg intakes that exceed the tolerable daily intake limits recommended by the Food and Agricultural Organization/World Health Organization (FAO/WHO) and US Environmental Protection Agency (USEPA). These results show the need for recommendations about swordfish consumption by population groups at risk in Spain.  相似文献   

7.
The metal contents in 42 fenugreek samples, cultivated in various agricultural areas of Pakistan, were determined using atomic absorption spectrophotometry. The concentrations of the metals—Cu, Mn, Cd, Ni, Co, Cr, Pb, Zn, Fe, Na and K—were found to be higher than those reported earlier. Particularly, the samples cultivated near the major industrial cities showed significantly higher levels of almost all the metals investigated in this study. The high concentration ranges of toxic metals, such as Cd 1·0–2·8, Pb 2·5–3·4, and Cr 17–19·8 mg kg?1, in a fairly large number of samples suggest a possible increase of the overall intake of these metals to potentially harmful levels.  相似文献   

8.
ABSTRACT

Samples of the edible mushroom Boletus edulis Bull. were studied to assess the risk for human health related to their content of the artificial radionuclide 137Cs. Fresh B. edulis carpophores were collected in four undeveloped microhabitats of Lucca province (Tuscany, North-Central Italy). Dried non-cultivated samples coming from this same district and 11 other Italian provinces or European countries were instead purchased fromcommercial sources. Contents of 137Cs, reported as Bq kg?1 dry weight (dw), were measured by γ-spectrometry. The radionuclide concentration varied depending on the gathering site in fresh samples, with 41.8 ± 5.2 Bq kg?1 dw at site 1 (Tosco-Emiliani Apennine) and four-fold less, 12.8 ± 1.3 Bq kg?1 dw, at site 2 (Apuan Alps). Moreover, fresh or dried carpophores from Lucca province displayed among the lowest 137Cs contents in Europe. Average 137Cs levels in all analysed samples were substantially below the legal threshold for edible mushrooms, 600 Bq kg?1 dw. Conclusively, we report that 137Cs amounts in B. edulis depend on both the distance from the Chernobyl accident and multifactorial features of collection sites. We also show that the consumption of European B. edulis does not represent a major health risk with respect to 137Cs radio contamination.  相似文献   

9.
BACKGROUND: Human exposure to heavy metals is attributed to consumption of vegetables raised in polluted soil environment. We examined the concentrations of As, Cd, Co, Cr, Cu, Ni, Pb and Zn in soils and lettuce (Latuca sativa) and amaranthus (Amaranthus caudatus) in 15 garden fields under long‐term wastewater irrigation. RESULTS: The concentrations of As (0.3–2.1 mg kg?1), Cd (0.07–0.3 mg kg?1), Co (4.6–9.1 mg kg?1) and Cr (21.6–36.2 mg kg?1) in the gardens were consistent with background concentrations in soils, but Ni (12.6–25.7 mg kg?1), Cu (12.5–24.6 mg kg?1), Pb (25.7–71.6 mg kg?1) and Zn (52.3–158 mg kg?1) concentrations were double the concentrations normally encountered in arable fields in the region. The concentrations of Cd and As in the vegetables were within safe limits, but Co (0.14–0.67 mg kg?1 fresh weight (fw)) and Ni (1.0–2.7 mg kg?1 fw) concentrations in lettuce were relatively high for leaf vegetables. The concentration of Pb (0.65–4.80 mg kg?1 fw) was above safe limit of 0.3 mg kg?1 fw, while the concentrations of Cu (1.3–2.7 mg kg?1 fw and Zn (10.2–23.6 mg kg?1 fw) were close to the unsafe limits for leaf vegetables. There were no strong linear correlations between soil metal concentrations and bio‐concentrations in the vegetable crops. CONCLUSION: We surmise that leaf vegetables can accumulate metals in their tissues to unsafe levels even when total metal concentrations in these soils are below the allowable concentrations in agricultural soils. Copyright © 2008 Society of Chemical Industry  相似文献   

10.
Toxic and essential elements in 11 different sea cucumber species were determined and compared with daily intake recommendations and maximum allowed levels. The contents of macro-elements contents in dried sea cucumber samples were found to be 25,000–152,000?mg?kg–1 for Na, 4000–8600?mg?kg?1 for Mg, 1100–5200?mg?kg?1 for K, 15,000–68,000?mg?kg?1 and 36,300–251,000?mg?kg?1 for Cl. Trace element concentrations in dried sea cucumber samples were found to be 11–100?mg?kg?1 for Zn, 41–660?mg?kg?1 for Fe, 3–74?mg?kg?1 for Cu, 1.1–16?mg?kg?1 for Mn, 1.4–3.7?mg?kg?1 for Se, 1.1–9.6?mg?kg?1 for Cr, and 0.3–5.1?mg?kg?1 for Ni. All sea cucumber species were rich sources of Na, Cl, Mg, Ca, Fe, Cu, Se and Cr for human consumption. Regarding contaminants, As, Cd and Pb concentrations in dried sea cucumbers were in the ranges of 1.1–6.1, 0.03–0.06 and 0.11–0.69?mg?kg?1, respectively. Moreover, Hg values of 11 sea cucumbers were below the detection limit (0.01?mg?kg?1).  相似文献   

11.
Accumulation levels of trace elements in edible tissues of three shrimp species (Penaeus semisulcatus, Parapenaeus longirostris and Paleomon serratus) from the Gulf of Antalya, Turkey were investigated. Copper (Cu), cadmium (Cd), zinc (Zn), iron (Fe) and manganese (Mn) concentrations were determined by atomic absorption spectrophotometry. The lowest Cu (1.33 mg kg?1) and Cd (0.23 mg kg?1) and highest Mn (1.52 mg kg?1) concentrations were found in P. longirostris, the lowest Zn (6.25 mg kg?1), Fe (1.84 mg kg?1) and Mn (0.25 mg kg?1) concentrations in P. serratus and the highest Cu (6.19 mg kg?1), Cd (2.36 mg kg?1), Zn (30.84 mg kg?1) and Fe (33.89 mg kg?1) concentrations in P. semisulcatus. The Cd levels detected in P. semisulcatus and P. serratus were above legislative limits. Our results show that there were significant differences in trace element concentrations among the three shrimp species. The highest levels of the five trace elements investigated, with the exception of Mn, were found in edible tissue of P. semisulcatus. Copyright © 2007 Society of Chemical Industry  相似文献   

12.
Concentration levels of As, Cd, Hg, Pb, Tl, Sn, Sb Co, Cu, Mn, Se, Zn, Cr, Ni and Mo in different types of rice cultivated in irrigated fields in Brazil were evaluated. Arsenic, Cd, Pb, Zn, Mn and Cu were found in higher concentrations in brown rice samples, suggesting the prevalence of these elements in the bran. Meanwhile, lower concentrations of Pb, Mo, Cr, Se and Co were found in parboiled rice. Organic rice did not differ of cultivated conventionally rice. Thallium, Hg and Sb were not detected in any rice sample whose limits of detection were 0.7 μg kg?1, 2.5 μg kg?1 and 8 μg kg?1, respectively. The concentrations of the investigated elements were compared with those reported for polished rice and brown rice from other countries, unveiling concentrations in general at the same level for rice produced at non-contaminated sites.  相似文献   

13.
BACKGROUND: It is important to determine the concentrations of essential and non‐essential metals in fish for human health. The essential elements and contaminants (Pb and Cd) were determined seasonally in the muscle and liver of some pelagic fish species round herring (Etrumeus teres), chub mackerel (Scomber japonicus), golden grey mullet (Liza aurata) and Mediterranean horse mackerel (Trachurus mediterraneus) from the Iskenderun Bay, Eastern Mediterranean Sea. RESULTS: The Na, K, Ca and Mg were the most abundant elements in muscle and liver tissues. The Na, K, Ca and Mg concentrations in fish tissues were between 51.7 and 3426 mg kg?1. Muscle accumulated the lowest levels of elements. Trace element and contaminant levels in muscle were highest in spring and summer. The Cu, Zn and Cr concentrations were highest in summer. The Ni, Mn and Fe concentrations were highest in spring. The maximum Pb concentrations in the muscle and liver of fish species was 0.39 and 0.80 mg kg?1 in autumn. The maximum Cd concentration in the muscle of fish was 0.27 mg kg?1 in spring and the maximum Cd concentration in the liver was 0.78 mg kg?1 in summer. CONCLUSION: The Cr, Pb, Cd, Cu and Zn levels in muscle were found to be lower than permissible limits reported by various authorities. Estimated weekly and daily intake for Pb and Cd by consumption of fish muscle were far below the PTWI and PTDI values established by FAO/WHO. Copyright © 2009 Society of Chemical Industry  相似文献   

14.
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   

15.
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   

16.
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   

17.
The purpose of this study was to measure acrylamide (AA) levels and selected parameters of different traditional Turkish coffees. AA, 5-hydroxymethylfurfural (HMF), total reducing sugar, protein, pH, moisture, dry matter (DM) as well as ash, caffeine and soluble solids content (SSC) in DM, L*, a*, b* colour parameters of coffee samples were determined and the correlation between AA level and these parameters were investigated. A total of 36 coffee samples (20 Turkish, 8 Dibek and 8 Terebinth coffee) from the Turkish market were examined. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was validated for the detection and quantitation of AA in coffee samples. The calibration curve was linear (R2 ≥ 0.999) over the range of 30–1000 μg kg?1. The limit of detection (LOD) and limit of quantification (LOQ) were found as 4.6 μg kg?1 and 15.5 μg kg?1, respectively. The amounts of AA in analysed coffee samples were in the range 31.1 ± 0.6 to 323.4 ± 5.4 µg kg?1. The highest mean AA levels were found in Terebinth coffees (240.3 μg kg?1) followed by Turkish coffees (204.3 µg kg?1) and then Dibek coffees (78.6 µg kg?1). No tested Turkish coffee samples had an AA concentration above the indicative value (450 µg kg?1) for roast coffee recommended by the European Commission (EC) in 2011. In addition, a strong positive correlation was found between HMF values and AA amounts of selected coffee types.  相似文献   

18.
In this study, 88 randomly selected samples of butter produced in the Black Sea region of Turkey were purchased from different retail markets during different periods and investigated for toxic and essential elements content. Quantitative analyses of elements in the samples were performed using an inductively coupled plasma-mass spectroscopy (ICP-MS). Mean concentrations of As, Cr, Cu, Fe, Mn, Ni, Pb, Se and Zn in the butter samples were 18.93, 100.32, 384.66, 4199.1, 887.47, 168.64, 56.13, 16.34 and 384.66 µg kg?1, respectively. Cd and Co were detected in 19 (mean content 0.29 µg kg?1) and 81 (mean content 3.81 µg kg?1) samples of 88 butter samples, respectively. However, the dietary intake of these elements by the population of the Black Sea region is currently well below the dietary reference intake (DRI) and provisional tolerable weekly intake (PTWI) levels of essential and toxic elements.  相似文献   

19.
A method using accelerator mass spectrometry (AMS) has been developed to offer a more sensitive alternative to scintillation techniques for the determination of chlorine-36 (36Cl) in foods. The main problem in method development was the potential interference of the sulfur-36 (36S) isobar. This was overcome by reducing the sulfur level of acid digests of food by precipitation of chloride as silver chloride, then purification by washing, dissolution and reprecipitation to present silver chloride as the AMS target. The limit of detection was around 0.1 Bq kg?1 and the limit of quantitation was around 0.2 Bq kg?1. The AMS method was only semi-quantitative at the lowest levels of interest. To test the method a few samples of milk (five) and blackberries (three) collected from near two nuclear power stations as potential sources of contamination were analysed. Blackberries spiked at 0.2 Bq kg?1 and milk spiked at 0.1 Bq kg?1 could be distinguished from method blanks. There was no 36Cl detectable in the unspiked samples.  相似文献   

20.
In this study, 22 species of medicinal plants (anise, centaury, chamomile, fennel, flax, green tea, indian hemp, laurel, licorice, linden, marestail, melissa, nettle, oat, red clover, riesenfenchel, rosehip, rosemary, sage, senna tea, yam, yarrow) were taken from five different local herbalists in Hatay. Chromium concentrations were determined by inductively coupled plasma-atomic emission spectroscopy. The highest chromium concentrations were detected in chamomile (4.21 ± 0.18 mg kg?1), licorice (2.80 ± 0.12 mg kg?1), melissa (2.71 ± 0.10 mg kg?1), marestail (2.66 ± 0.10 mg kg?1), and anise (1.98 ± 0.06 mg kg?1). Minimal concentrations of chromium were found in riesenfenchel (0.33 ± 0.01 mg kg?1), red clover (0.37 ± 0.01 mg kg?1), centaury (0.43 ± 0.01 mg kg?1), senna tea (0.49 ± 0.01 mg kg?1), and linden (0.50 ± 0.01 mg kg?1). Cr(III) and Cr(VI) concentrations in medicinal herbs were found in the range of 0.26–3.12 mg kg?1 and 0.07–1.09 mg kg?1, respectively.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号