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1.
As the brown meat of crabs accumulates cadmium (Cd) to elevated concentrations, the European Commission has recommended consumer advice on the consumption of such seafood products. To supplement available data, 397 samples (including whole crabs and products containing brown crab meat) were collected from UK retailers. Cd concentrations ranged from 0.01 to 26 mg kg −1 wet weight (ww) and mean and median concentrations of 3.4 and 2.8 mg kg−1 were found, respectively. Although there is no regulatory limit for Cd in brown crab meat, mean concentrations were above the permitted maximum of 0.5 mg kg−1 that applies to the white meat component derived from claws and legs. These data will support the UK Food Standards Agency’s risk assessment and management measures regarding the consumption of brown crab meat by UK consumers.  相似文献   

2.
A rapid, sensitive, accurate and reliable multiresidue method for quantification and confirmation of 121 common agricultural pesticides in fruits and vegetables by gas chromatography in tandem with mass spectrometry was developed, validated and applied to 1463 vegetable and fruit samples collected over one year from extensive greenhouse cultures in Almería (Spain). Prior to instrumental analysis an extraction procedure, based on a sample extraction of multi-class analytes according to QuEChERS method (quick, easy, cheap, effective, rugged and safe) with some modifications was used. Mass spectrometric conditions were individually optimized for each analyte to achieve maximum sensitivity in the Selected Reaction Monitoring (SRM) mode. The scan times for each segment were between 0.8 and 1.0 s, with a maximum of 35 transitions per segment. Use of two reactions for each pesticide allowed simultaneous quantification and identification in one run. The pesticides were separated in less than 30 min. Recovery and precision were evaluated in nine representative matrices (tomato, pepper, lettuce, cucumber, eggplant, zucchini, melon, watermelon and apple). The mean recoveries ranged from 80% for thiometon to 116% for heptenophos, with relative standard deviations lower than 20% for all components. Only three pepper samples, one of tomato and one of cucumber had residues above the maximum allowable residue (0.01 mg kg−1) according to European Union directives. The method was accredited according to UNE-EN ISO/IEC 17025:2005 international standard.  相似文献   

3.
Concentrations of the macroelements Ca, Mg, K and Na, microelements Cr, Cu, Fe, Mn and Zn and toxic metals As, Cd, Hg and Pb were determined in oysters and mussels collected at farming sites in the northern, central and south Adriatic Sea. Mean concentrations in oysters were (mg kg−1): As 4.51, Ca 1551, Cd 1.44, Cu 53.6, Cr 0.23, Fe 45.9, Hg 0.047, K 2476, Mg 895, Mn 2.80, Na 7148, Pb 0.52, Zn 675. Mean values in mussels were (mg kg−1): As 4.71, Ca 601, Cd 0.37, Cu 1.91, Cr 0.29, Fe 49.6, Hg 0.026, K 2246, Mg 1043, Mn 2.49, Na 7992, Pb 0.58, Zn 28.8. Significant differences in the concentrations of toxic metals and elements were found in oysters and mussels among farming sites. Obtained Cd, Hg and Pb concentration in oysters and mussels were lower than the limit levels set by the European Community. However, Cd concentration exceeded the limit level of 1 mg kg−1 in oysters from all locations except Lim Bay. The estimated daily intakes (EDIs) indicate that oysters are a good source of Ca, Cu and Zn. The higher Cu and Zn concentrations than the toxicity reference values suggest a risk for consumers if larger quantities of oysters are consumed frequently.  相似文献   

4.
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   

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.
Rapadura is the commercial name for unrefined dehydrated sugarcane juice. Rapadura is produced in 25 countries, for an estimated total of 13 million tons per year. It is considered a basic food for the School Meals Program (PNAE) in Brazil, which serves 37 million meals to schoolchildren each day. During the production of rapadura, carcinogenic compounds including polycyclic aromatic hydrocarbons (PAHs) may enter this food. A simple and rapid method was optimized and validated for the determination of 16 PAHs in commercial rapadura by high performance liquid chromatography with fluorescence detection (HPLC-FL). PAHs were measured in 80% of the samples (n = 21) at levels ranging from 0.07 to 4.03 μg kg−1. These data reveal a wide variability in PAH concentrations in the samples, indicated that sugar-cane burning and/or production are important for introduction of these contaminants into rapadura. In Brazil, there are no maximum acceptable PAH levels in this food.  相似文献   

7.
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   

8.
A greenhouse pot experiment was carried out to study the responses of Cynara cardunculus L. (cardoon) to cadmium and nickel. Three groups of 12 pots each were planted with cardoon plants and spiked with single and combined cadmium and nickel aqueous solutions. The bioavailable metal concentrations, measured in soil, ranged widely and were up to 246.7 mg kg−1 for Cd and 61.1 mg kg−1 for Ni. Under Cd treatment, cardoon growth remained unaffected, while increased Ni soil concentrations inhibited plant growth and were lethal to the highly treated plants. In the combined Cd and Ni treatments, an antagonistic effect was observed between the two metals. Cadmium and nickel concentrations in cardoon tissues rose with increasing metal concentrations in the soil. Cadmium and nickel contents in shoots reached 169.3 and 342.3 mg kg−1 in the single treatments while, under the combined Cd and Ni treatments, they were up to 235.0 and 440.7 mg kg−1, respectively. Generally, mean contents of both metals in the shoots were higher than in the roots and the translocation factor was greater than 1. A possible enhancing effect of nickel on cadmium uptake was observed. Cardoon showed characteristics of a Cd accumulator.  相似文献   

9.
A semi-static solution culture method was used to study the effects of Ca2+ supply and interaction of Cd–Pb on the subcellular distribution of Cd and Pb in earthworm Eisenia fetida. The subcellular distribution of Cd and Pb was shown to be metal specific. About 80% of the Cd was distributed in the cytosol (fraction G), and only about 20% of total Cd was found in the tissue and cell membrane (fraction E) and the microsomes (fraction F). Nearly 50% of the Pb was rich in the tissue and cell membrane (fraction E). The supply of Ca2+ ions significantly decreased Cd concentration in the cytosol (fraction G) and the whole tissue of the E. fetida. At the subcellular level, the addition of Pb2+ ions significantly decreased the Cd percentage associated with fraction G from 83.7% to 58.4% and increased fraction E from 10.7% to 34.0%, respectively.  相似文献   

10.
The aim of the present study is to investigate the pollution vulnerability of groundwater aquifers in the coastal regions of Tuticorin city, Tamil Nadu, India. Fourteen samples were analyzed to determine the concentration of trace elements (Pb, Zn, Cd, Hg, Cr and Cu) in the groundwater. Among the total samples six were collected from industrial areas and eight from non-industrial areas of Tuticorin city. The concentration of trace element ranges from 0.01 to 0.19 mg/kg−1 for Pb, from 0.01 to 0.16 mg/kg−1 for Zn, from BDL to 0.21 mg/kg−1 for Cd, from BDL (Below Detection Limit) to 0.023 mg/kg−1 for Hg, from 0.02 to 0.18 mg/kg−1 for Cr and from 0.01 to 0.16 mg/kg−1 for Cu. The trace element concentration in groundwater is higher than the WHO suggested maximum permissible limit except Zn and Cu.  相似文献   

11.
The objective of the present work was to determine the bioaccumulation of arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), mercury (Hg), uranium (U) and selenium (Se) in gill, liver, and muscle tissues of the fresh water fish Salmo trutta macrostigma (Duméril, 1858) in Munzur Stream, Tunceli, Turkey. The highest concentrations of U (1.83?μg?kg?1), Pb (119.84?μg?kg?1) and Se (1.31?μg?kg?1) were recorded in the gills of S. t. macrostigma. Concentrations of As (46.27?μg?kg?1), Cd (109.19?μg?kg?1), Hg (16.40?μg?kg?1), Cu (18.19?μg?kg?1) were recorded at highest levels in the liver. The results showed that there were significant differences in concentrations of As, Cd, Cu, Pb, Se, U and Hg in gill, liver and muscle tissue (p?<?0.05). Heavy metals were within the edible parts of the investigated fish were in the permissible safety levels for human uses.  相似文献   

12.
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   

13.
The present research project was undertaken to determine heavy metal (Pb, Co, Cd, Cr, Cu, Fe, Mn and Zn) concentrations in intensive aquaculture and wild white shrimp tissues (muscle, shell and liver), and to inform aquatic shrimp food safety. The aquaculture samples were obtained from ten intensive farms and wild animals from one station in Zhanjiang Harbour Bay. Heavy metal concentrations (mg kg−1, dry weight; means ± S.D.) in aquaculture white shrimp muscle, shell and liver tissues were, respectively: Cr - 20.86 ± 5.27, 28.70 ± 8.34 and 18.91 ± 5.50, Cu - 24.26 ± 8.36, 30.86 ± 9.84 and 126.42 ± 90.9, Fe - 61.35 ± 30.76, 55.07 ± 17.72 and 124.04 ± 56.15, Mn - 5.33 ± 2.5, 10.72 ± 4.34 and 8.79 ± 5.29, Zn - 171.56 ± 118.74, 51.84 ± 10.94 and 111.74 ± 84.67. Cadmium was observed only in liver tissue at 3.30 ± 1.29 mg kg−1. Lead could not be detected, and cobalt was detected only in wild shrimp liver tissue. Chromium and manganese mean concentrations in shell tissue were significantly higher than levels in muscle tissue (P < 0.05), but the zinc mean concentration was significantly lower than noted in muscle tissue (P < 0.05). Copper and iron mean concentrations in liver tissue were significantly higher than those in muscle or shell tissues (P < 0.05). Overall, only chromium in white shrimp tissue was the primary risk for human health.  相似文献   

14.
The concentration of Cr, Zn, Ni, V, Pb, and Cd were measured in lingonberries (Vaccinium vitis-idaea L.) sampled at 23 sampling sites around a ferrochrome and stainless steel works and opencast chromium mine in the Kemi-Tornio region, Northern Finland. Two different microwave-assisted digestion procedures were used for sample digestion, i.e., a mixture of HNO3 + H2O2 and a mixture of HNO3 + H2O2 + HCl + HF + H3BO3. According to the results, the digestion procedure with the mixture of HNO3 + H2O2 underestimated especially the Cr concentrations in plant material. The maximum concentrations of Cr (1.3 mg kg–1, wet weight), Ni (358 g kg–1; ww), V (36 g kg–1; ww), and Cd (2.4 g kg–1; ww) in the immediate vicinity of the point sources were 33, 6, 4, and 8 times higher than the background levels, respectively. The dietary intakes of Cd and Pb were assessed and compared to the health criteria recommendations set by the joint Food and Agriculture Organization and World Health Organization Expert Committee on Food Additives (JECFA). The results showed that, depending on the consumption of lingonberries, human exposure based on the mean concentrations for Pb and Cd varied between 0.04% and 0.07% for Pb and between 0.04% and 0.09% for Cd compared to the tolerable total quantities of 25 g kg–1 for Pb and 7 g kg–1 for Cd per body weight per week set by JECFA.  相似文献   

15.
Lemna minor L. was used to investigate the toxic effects of Pb and Hg either alone or in various binary mixtures under the static test conditions. A full-strength Jacob culture medium was used for the long-term cultivation of duckweeds and the experiments. Tests were run for 4 and 7 days. The EC50 values for Pb was estimated as 6.8±0.2 mg L−1 and 5.5±0.1 mg L−1 for a 4 and a 7-day test periods, respectively. Hg was much more toxic than Pb with the EC50 of 0.64±0.03 mg L−1 (4 days) and 0.48±0.02 mg L−1 (7 days). The amounts of Pb uptake by the plants were determined by atomic absorption spectrometer (AAS). The cold vapor AAS-technique (CV-AAS) was used for Hg determination. The interactive effect between Pb and Hg on growth was evaluated as additive on the basis of statistical data analysis. However, an antagonistic interaction was observed on the metal accumulation efficiency.  相似文献   

16.
This study was undertaken to evaluate the vertical and horizontal distribution of lead (Pb), cadmium (Cd), and zinc (Zn) in farmlands around a Pb-contaminated goldmine. Total concentrations of Pb and Cd recorded were at maximum values of 2,246.55 and 68.7 mg kg?1, respectively; these are greater than the threshold values for Pb (300 mg kg?1) and Cd (3 mg kg?1). However, the concentration of Zn was within acceptable limits (300 mg kg?1). Down the soil profile, concentrations of Pb, Cd, and Zn showed two peaks; these were attributed to facilitated transport and ground-water enrichment. Incubation of the soil samples with glucose indicated low microbial process(es), which could be due to the increased levels of Pb and Cd. Factor analysis showed a close association of Pb and Cd with the soil-exchange complex with a possibility of these heavy metals replacing Ca and other divalent cations in the soil-exchange site. This will, however, increase the risk of Pb and Cd leaching and uptake by plants. Although the metals were more associated with resistant soil fraction (sand), which also indicates their geogenic origin, chemical weathering under the influence of pH could release these metals into the soil-exchange site.  相似文献   

17.
Selenium content of Portuguese unifloral honeys   总被引:1,自引:0,他引:1  
The selenium contents of a total of 62 unifloral honeys from Erica spp., Castanea sativa, Eucalyptus spp., Lavandula stoechas, Citrus spp. and Echium plantagineum honeys collected in Portugal were determined by fluorometry after reaction with 2,3-diaminonaphthalene. The selenium levels of the honey samples studied were low, ranging from <1.0 to 2.91 μg/100 g fresh weight. The honeys from Erica spp., C. sativa and E. plantagineum presented the highest selenium values from all the honeys studied (median values 1.69, 1.51 and 1.51 μg/100 g fresh weight), and the honeys from Eucalyptus spp., L. stoechas and Citrus spp. presented the lowest values (median values 1.33, 1.28 and 1.20 μg/100 g fresh weight). The selenium content of Erica spp., was significantly higher than that observed for the Eucalyptus spp., L. stoechas and Citrus spp. and the selenium level of the Eucalyptus spp., was also significantly lower than that observed C. sativa and E. plantagineum honeys. From these results it can be concluded that honey is a marginal source of Se for the Portuguese population.  相似文献   

18.

Increases in the levels of environmental contaminants are reflected in wild animals, which are early indicators of pollution. Hatay is an ecologically important region with a high intensity of industrial and agricultural activities. This study aimed to investigate the contamination levels of metals and organochlorine pesticides associated with environmental pollution in tissues of wild boars from Turkey. The highest mean levels (mg kg−1) of metals were 0.05 for As, 0.51 for Cd, 6.30 for Cu, 0.07 for Hg, 0.54 for Ni, and 0.57 for Pb in kidney tissues and 0.22 for Cr, 353.38 for Fe, 2.86 for Mn, and 46.76 for Zn in liver tissues. The Cd and Pb levels exceeded the maximum residue limits (MRLs) in some tissues. Among the studied pesticides, only p,p′-DDE contamination was quantified, and the mean levels were 3.6, 0.1, and 0.5 µg kg−1 in liver, kidney, and muscle tissues respectively. In conclusion, Hatay Province requires monitoring in terms of environmentally important contaminants, mainly Cd, Pb, and DDT isomers.

  相似文献   

19.
Crops produced on metal-polluted agricultural soils may lead to chronic toxicity to humans via the food chain. To assess metal pollution in agricultural soils and soybean in southern China, 30 soybean grain samples and 17 soybean-field soil samples were collected from 17 sites in southern China, and metal concentrations of samples were analyzed by graphite furnace atomic absorption spectrophotometer. The integrated pollution index was used to evaluate if the samples were contaminated by Cd, Pb, Zn and As. Results showed that Cd concentration of 12 samples, Pb concentration of 2 samples, Zn concentration of 2 samples, and As concentrations of 2 samples were above the maximum permissible levels in soils. The integrated pollution index indicated that 11 of 17 soil samples were polluted by metals. Metal concentrations in soybean grain samples ranged from 0.11 to 0.91 mg kg?1 for Cd; 0.34 to 2.83 mg kg?1 for Pb; 42 to 88 mg kg?1 for Zn; and 0.26 to 5.07 mg kg?1 for As, which means all 30 soybean grain samples were polluted by Pb, Pb/Cd, Cd/Pb/As or Pb/As. Taken together, our study provides evidence that metal pollution is an important concern in agricultural soils and soybeans in southern China.  相似文献   

20.
The contents of arsenic, mercury, lead and cadmium in milled rice were determined. Among 216 genotypes, the As, Hg, Pb and Cd contents were ranged from 5.06 to 296.45, 2.46 to 65.85, 4.16 to 744.95 and 5.91 to 553.40 ng/g, respectively. Six genotypes with lower contents of toxic metal elements were selected. The averages of As and Pb contents for indica rice were higher than those of japonica rice, while the averages of Hg and Cd contents were in contrast. Compared with white brown rice, the milled rice from black and red brown rice contained lower contents of four elements. Significant negative correlation was found between As content and alkaline spread value. Significant correlations were observed between As and aspartic acid (Asp) content, Hg and Asp or leucine contents, Pb and cysteine or methionine contents. Cd content was significantly negatively correlated with protein and 14 amino acid contents.  相似文献   

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