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1.
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   

2.
BACKGROUND: In most parts of Pakistan, untreated city effluent is utilised for growing vegetables around large urban settlements such as Faisalabad. Farmers use it as a source of irrigation water and plant nutrients. However, its continuous use may have serious environmental implications, since it also contains heavy metals. In this study the Faisalabad city effluent was examined for irrigation quality and its impact on irrigated soils and vegetables. RESULTS: Irrigation hazard of the effluent was moderate (electrical conductivity (EC) 1.1–1.7 dS m?1, Sodium adsorption ratio (SAR) 5.9–17.4 mmol1/2 L?1/2, Residual sodium carbonate (RSC) 1.0–2.1 mmolc L?1) at site 1 and strong (EC 3.7–4.1 dS m?1, SAR 16.1–21.8 mmol1/2 L?1/2, RSC 4.0–9.1 mmolc L?1) at site 2. Mean concentrations of ammonium bicarbonate/diethylene triamine pentaacetic acid (AB/DTPA)‐extractable Cd, Co and Mn at upper soil depth (0.0–0.2 m) were respectively 0.080, 0.057 and 217.4 mg kg?1 at site 1 and 0.101, 0.076 and 164.1 mg kg?1 at site 2. CONCLUSION: The concentrations of Cd and Mn were above the permissible limits but that of Co was below the permissible limit for irrigation. The concentrations of Cd, Co and Mn tended to decrease with increasing soil depth. Accumulation of metals was higher in leaves irrespective of whether leaves were the edible or non‐edible component of shoots. Use of untreated city effluent for irrigation without risk assessment and management could be a serious hazard, impacting soil and crop quality and ultimately human health. Copyright © 2007 Society of Chemical Industry  相似文献   

3.
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   

4.
BACKGROUND: A 3‐year field trial was conducted to investigate the effect of agricultural management practices including tillage, preceding crop and phosphate fertilization on root colonization by arbuscular mycorrhizal (AM) fungi and grain cadmium (Cd) concentration of durum wheat (Triticum turgidum L.). The relationship between grain Cd and soil and plant variables was explored to determine the primary factors affecting grain Cd concentration. RESULTS: Mycorrhizal colonization of the roots was reduced by conventional tillage or when the preceding crop was canola (Brassica napus L.), compared to minimum tillage or when the preceding crop was flax (Linum usitatissimum L.). In contrast, grain Cd was not consistently affected by any treatment. Grain Cd was generally below the maximum permissible concentration (MPC) of 100 µg Cd kg?1 proposed by WHO. Grain Cd varied substantially from year to year, and could be predicted with 70% of variance accounted for by using the model: grain Cd concentration = ? 321.9 + 44.5× ln(grain yield) + 0.26× soil DTPA‐Cd + 182.5× soil electrical conductivity (EC)? 0.98× grain Zn concentration. CONCLUSIONS: These common agricultural management practices had no effect on grain Cd concentration in durum wheat though they impacted mycorrhizal colonization of roots. Grain yield and to a lesser extent soil conditions of EC and DTPA‐Cd and grain Zn influenced grain Cd, whereas mycorrhizal colonization levels did not. Copyright © 2010 Crown in the right of Canada. Published by John Wiley & Sons, Ltd  相似文献   

5.
Accumulation of toxic metals in liver, a rich natural source of essential elements, can present health risks to regular consumers of liver. A total of 35 fresh liver samples of cow, sheep, goat, pig, grass-cutter (Thryonomys swinderianus), gaint rat (Cricetomys gambianus), red deer (Cervus elaphus), chicken and antelope (Antilocapra americana) were obtained from three different markets in Accra and Kumasi, Ghana. Samples were analyzed using atomic absorption spectrometry and an automatic mercury analyzer. Levels of iron in the grass-cutter and pig of 500.5–645.4 mg kg?1 were the highest in the animal livers examined. Mn concentrations were highest in grass-cutter and rat liver, ranging 16.5–30.2 mg kg?1. The safe Cu and Zn permissible limits of 20 and 50 mg kg?1 were exceeded in 70 and 75% of the liver samples, respectively. Generally, for each animal group studied, at least 50% of the sample livers exceeded the Cd permissible limit of 0.5 mg kg?1. The levels of Pb, which ranged 1.3–13.8 mg kg?1, exceeded the proposed European Commission (EC) limit of 0.5 mg kg?1. Care must be taken by regular consumers of the iron-rich animal livers of grass-cutter, pig and rat because they also had the highest levels of Pb (in grass-cutter and pig) and Cd (in grass-cutter, rat and pig). The liver samples analyzed for Hg had values far below the permissible limit of 0.5 mg kg?1.  相似文献   

6.
The plant sterol contents of the most important vegetables, fruits and berries available in Finland were determined by capillary gas chromatography. The sample preparation procedure included both acid and alkaline hydrolysis to liberate sterols from their conjugates. The plant sterol contents of fresh vegetables ranged from 51 to 370 mg kg?1 fresh weight (fw) in samples obtained from retail sale. The highest contents (>300 mg kg?1) were measured in broccoli, Brussels sprouts, cauliflower and dill and the lowest (51 mg kg?1) in potato. The range of sterol contents on a dry weight (dw) basis was high, 246–4100 mg kg?1 dw. Considerable variation was also observed when individual samples of some vegetables were compared. Sitosterol was the main sterol (proportion 43–86%) in all vegetables except cucumber and spinach, in which Δ7‐sterols dominated. The total sterol contents were in the range 116–228 mg kg?1 fw in all fresh fruits except avocado, which contained more sterols, 752 mg kg?1 fw. In fresh berries the corresponding range was 60–279 m kg?1 fw. The wild berries lingonberry and blueberry were better plant sterol sources than the cultivated berries blackcurrant, redcurrant and strawberry. In fruits and berries the proportion of sitosterol ranged from 61–93% total sterols. On the basis of the results, the contribution of vegetables, fruits and berries to the total average daily plant sterol intake was estimated to be ca 60 mg. © 2003 Society of Chemical Industry  相似文献   

7.
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   

8.
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   

9.
This study was carried out to determine the current levels of nitrates in vegetables and vegetable-based baby foods (a total of 1150 samples) marketed in the Region of Valencia, Spain, over the period 2000–2008, and to estimate the toxicological risk associated with their intake. Average (median) levels of nitrate in lettuce, iceberg-type lettuce and spinach (1156, 798 and 1410 mg kg?1 w/w, respectively) were lower than the maximum limits established by European Union legislation. Thirteen fresh spinach samples exceeded the regulatory limits. Median nitrate values in other vegetables for which a maximum limit has not been fixed by the European Commission were 196, 203, 1597, 96, 4474 and 2572 mg kg?1 w/w (for potato, carrot, chard, artichoke, rucola and lamb's lettuce, respectively). The estimated nitrate daily intakes through vegetables consumption for adult, extreme consumers and children were found to be about 29%, 79.8% and 15.1%, respectively, of the acceptable daily intake (3.7 mg kg?1). The levels (median = 60.4 mg kg?1 w/w) found in vegetable-based baby foods were, in all cases, lower the maximum level proposed by European Union legislation. The estimated nitrate daily intake through baby foods for infants between 0–1 and 1–2 years of age were 13% and 18%, respectively, of the acceptable daily intake.  相似文献   

10.
BACKGROUND: The higher consumption of vegetables and fruits could be a practical approach to the management of oxidative stress. The present study sought to compare the antioxidant properties of polar and non‐polar constituents of some tropical green leafy vegetables (Struchium sparganophora, Amaranthus cruentus, Telfairia occidentalis, Ocimum gratissimum, Talinium triangulare, Cnidoscolous aconitifolius and Vernonia amygdalina). RESULTS: The polar antioxidant constituents (total phenol (3330–17 572 mg kg?1), total flavonoid (1668–4306 mg kg?1) and vitamin C (224–642 mg kg?1)) were higher than the non‐polar antioxidant constituents (total phenol (703–3115 mg kg?1), total flavonoid (130–1303 mg kg?1) and carotenoids (132–1303 mg kg?1)). Furthermore, the polar extracts had a significantly higher (P < 0.05) 1,1‐diphenyl‐2‐picrylhydrazyl radical scavenging ability (except T. triangulare), total antioxidant capacity, reducing power (except T. triangulare and A. cruentus) and Fe(II) chelating ability (except C. aconitifolius and S. sparganophora). However, the polar and non‐polar extract of O. gratissimum had the highest antioxidant properties while that of T. triangulare had the least antioxidant properties. CONCLUSION: The polar extract of most of the vegetables had higher antioxidant properties than the non‐polar extract, with O. gratissimum extracts having the highest antioxidant properties. Copyright © 2008 Society of Chemical Industry  相似文献   

11.
Heavy metal contamination in the food chain is of serious concern due to the potential risks involved. The results of this study revealed the presence of maximum concentration of heavy metals in the canal followed by sewerage and tube well water. Similarly, the vegetables and respective soils irrigated with canal water were found to have higher heavy metal contamination followed by sewerage- and tube-well-watered samples. However, the heavy metal content of vegetables under study was below the limits as set by FAO/WHO, except for lead in canal-water-irrigated spinach (0.59 mg kg?1), radish pods (0.44 mg kg?1) and bitter gourd (0.33 mg kg?1). Estimated daily intakes of heavy metals by the consumption of selected vegetables were found to be well below the maximum limits. However, a complete estimation of daily intake requires the inclusion of other dietary and non-dietary exposure sources of heavy metals.  相似文献   

12.
Two essential amino acids (methionine and tryptophan); anti‐nutritional factors (tannin and trypsin inhibitor) and toxic elements (Pb, Cd, Ni, As, Hg and Cr) were determined spectrophotometrically from five edible wild mushrooms. The tryptophan content was between 1.00 and 1.82 g (100 g)?1 but methionine was low at 0.26–1.38 g (100 g)?1. Tannin content was high (30.3–40.0 mg g?1) but trypsin inhibitor was low (22.0–39.5 TIU g?1). Trace elements analysis reviled Pb (0.34–5.06 mg kg?1) to be the highest of all the trace elements. Cd was (0.06–1.70 mg kg?1), Ni (0.26–2.08 mg kg?1), As (0.17–0.92 mg kg?1), Hg (0.01–0.05 mg kg?1) and Cr (0.04–0.22 mg kg?1). These mushrooms are nutritious but must be well processed to eliminate or at least reduce the levels of tannin and Pb to improve their nutritional values.  相似文献   

13.
Concentrations of eight heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn) were determined in economically important bivalve species: oyster (Ostrea edulis), wedge clam (Donax trunculus), manila clam (Ruditapes philippinarium) and warty clam (Venus verrucosa) from the Marmara and Aegean seas. Samples were collected seasonally between 2008 and 2009. Metal levels of bivalves were found in the following ranges: As 0.02–3.40, Cd 0.02–2.80, Cr 0.19–0.82, Cu 0.82–25.06, Hg?<?LOD–0.12, Ni 0.09–0.73, Pb 0.05–4.16 and Zn 6.85–899?mg?kg?1. The most abundant elements were Zn?>?Cu?>?As. In addition, the results showed that oysters had the highest concentrations of Zn in all seasons. The next abundant heavy metal detected was Cu in oyster and other clam species. It was concluded that in the future, these metals should be monitored regularly.  相似文献   

14.
Copper (Cu), cadmium (Cd), nickel (Ni), lead (Pb) and zinc (Zn) contents of various vegetables (cucumber, tomato, green pepper, lettuce, parsley, onion, bean, eggplant, peppermint, pumpkin and okra) produced in Kayseri, Turkey and the soils in which they were grown were determined using Inductively Coupled Plasma–Optical Emission Spectrometry (ICP–OES). These plants are the basis of human nutrition in the study area. The results obtained from the urban area were higher than those of the rural area as a result of pollution. The order of the elements in various vegetables and their concentration ranges in μg/g were Cu (22.19–76.5), Cd (0.24–0.97), Ni (0.44–13.45), Pb (3–10.7) and Zn (3.56–259.2). The concentrations of Cu, Zn and Ni in vegetables studied are within the recommended international standards. The results also show that onion (0.97 μg/g) and peppermint (76.5 μg/g) have the ability to accumulate more Cd and Cu than the other vegetables studied, respectively. Furthermore, there were statistically significant differences (P < 0.05) between the levels of Zn and Pb in all vegetables analyzed from urban and rural areas. Concentrations of metals analyzed in samples could be related to their concentration in the corresponding soils. Enhanced levels of metals observed in some vegetable species could be related to their concentration in the corresponding soils.  相似文献   

15.
The aim of this study was to determine the levels of copper (Cu), manganese (Mn), zinc (Zn), iron (Fe), cadmium (Cd), lead (Pb), chromium (Cr), nickel (Ni) and selenium (Se) in sunflower honeys obtained from Thrace Region of Turkey. Trace and toxic element determination was performed by atomic absorption spectrometry after microwave digestion. The accuracy of the method was checked by the standard reference material, NIST‐SRM 1515 Apple leaves. The maximum contents of trace and toxic elements in honey samples from Kesan (polluted area) were found as 0.46, 0.82, 1.98, 14.0, 9.86 μg kg?1, 0.48 mg kg?1, 137, 115 and 290 μg kg?1 for Cu, Mn, Zn, Fe, Cd, Pb, Cr, Ni and Se, respectively.  相似文献   

16.
BACKGROUND: A simple and quick on‐site test for trace levels of cadmium (Cd) in food is needed because of the human toxicity of this heavy metal. We developed an immunochromatography kit which uses the antigen‐antibody complex reaction between the Cd–ethylenediaminetetraacetic acid (Cd–EDTA) complex and an anti‐Cd–EDTA antibody. We previously reported the successful use of this kit to determine Cd concentrations in brown rice with respect to the international standard: 0.4 mg kg?1. Here, we measured, using this immunochromatography kit, Cd concentrations in crops with lower international standards than rice. RESULTS: Cadmium extracted with 0.1 mol L?1 HCl from wheat grain and fresh eggplant was purified sufficiently using an ion‐exchange column treatment. Appropriate HCl extraction rates and dilution rates for the column eluate were selected; Cd concentrations in wheat grain and fresh eggplant were determined successfully by immunochromatography with respect to the international standards of 0.2 mg kg?1 and 0.05 mg kg?1 fresh weight, respectively. CONCLUSION: Approximate Cd concentrations in wheat grain and fresh eggplant can be monitored easily and quickly by this method at locations where facilities for acid digestion and precision analysis are not available. Copyright © 2011 Society of Chemical Industry  相似文献   

17.
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   

18.
The aim of the study was to investigate the interactions between selenium (Se) and various trace elements, both toxic and essential, involved in the antioxidant system. A total of 128?day-old chicks (Gallus gallus, broilers) were used to investigate the effect of Se yeast supplementation on the accumulation of cadmium (Cd), copper (Cu) iron (Fe) and zinc (Zn). There were four replicates of four dietary treatments: T1 (basal diet with no added Se, analyzed to contain 0.21?mg?kg?1), T2 (T1 with 0.15?mg?kg?1 Se added), T3 (T1 with 0.3?mg?kg?1 Se) and T4 (T1 with 3.0?mg?kg?1 Se). At week 4 and 6, two chickens per replicate pen were sacrificed for whole blood, breast muscle and liver sampling. Samples were analyzed by ICP–MS. Supplementation with Se-yeast, not only increased Se concentration but also reduced Cd concentration in the tissues. Selenium was negatively correlated with Cd and positively correlated with Zn, Cu and Fe. Cadmium was negatively correlated with Zn and Cu. Zinc was positively correlated with Cu. Iron was negatively correlated with Cu and uncorrelated with Zn and Cd. The balance between Se, Cu, Fe and Zn is important for proper antioxidant defense since they are an integral part of various antioxidant enzymes.  相似文献   

19.
The aims of this study were to investigate the uptake of seven trace elements and five PAHs in crop plants in order to establish advice regarding consumption of fruit and vegetables grown in soils contaminated by trace elements and PAHs. In a field experiment, vegetables were grown in two contaminated soils and in a reference soil, whereas fruits were collected from uncontaminated and contaminated private gardens. The results showed elevated levels of several trace elements and PAHs in the vegetables from contaminated soil. Bioconcentration factors (BCF values), based on dry weight, were below 1, except for those of Cd in lettuce and carrot with peel from uncontaminated soil. In most cases, BCF values were decreasing with increasing concentrations in soil. From the heavily contaminated soil, BCF values for Pb in lettuce, potato, and carrot with peel were 0.001, 0.002, and 0.05, respectively, and those for benzo[a]pyrene were 0.004, 0.002, and 0.002, respectively. For most metals in most vegetables, linear regression showed good correlation between soil and crop concentrations. For PAHs, such good correlation was generally not found. The contents of contaminants in fruits were generally low and no correlation with the level of contamination in the soils was found.  相似文献   

20.
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   

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