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1.
Fruit juices are widely consumed in tropical countries as part of habitual diet. The concentrations of several minerals in these beverages were evaluated. Four commercially available brands of juices were analyzed for cadmium, lead, copper, zinc, aluminum, iron, chromium, manganese, and molybdenum. The levels ranged from 0.02 to 0.08 mg/L for copper, from 0.05 to 0.23 mg/L for zinc, from 0.1 to 0.4 mg/L for aluminum, from 0.02 to 0.45 mg/L for iron, and from 0.01 to 0.22 mg/L for manganese. The levels of cadmium, lead, and chromium in all samples were very low or undetectable. The metal contents of fruit juices depend on a number of factors, including the soil composition, the external conditions during fruit growing and fruit harvesting, as well as on details of the fruit juice manufacturing processes employed. The concentrations of none of the metals in juice samples analyzed exceeded the limits imposed by local legislation.  相似文献   

2.
Total aluminum, chromium, copper, iron, manganese, and nickel were determined in black tea, green tea, Hibiscus sabdariffa, and Ilex paraguariensis (mate) by electrothermal atomic absorption spectrometry after nitric/perchloric acid digestion. In each case, one ground sample of commercially available leafy material was prepared and three 0.5-g subsamples were run in parallel. The infusions were also analyzed and the percentage of each element leached into the liquor was evaluated. The obtained results indicated that hibiscus and mate contained lower levels of aluminum (272±19 μg/g and 369±22 μg/g, respectively) as referred to black tea (759±31 μg/g) or green tea (919±29 μg/g) and suggested that mate drinking could be a good dietary source of essential micronutrient manganese (total content 2223±110 μg/g, 48.1% leached to the infusion). It was also found that the infusion of hibiscus could supply greater amounts of iron (111±5 μg/g total, 40.5% leached) and copper (5.9±0.3 μg/g total, 93.4% leached) as compared to other infusions. Moreover, it was found that the percentage of element leached to the infusion was strongly related to the tannins content in the beverage (correlation coefficients >0.82 with the exception for nickel); for lower tannins level, better leaching was observed.  相似文献   

3.
The aim of this study was to determine the levels of cadmium, lead, iron, zinc, selenium, manganese, copper and molybdenum in different cuts of beef, pork, lamb, chicken and foal collected from supermarkets and butcheries in Switzerland. The concentrations of manganese, copper, molybdenum, zinc, iron, selenium, cadmium and lead were determined by inductively coupled plasma mass spectrometry (ICP-MS) after microwave digestion. Mean values and their respective coefficients of variation were calculated from the measured concentrations. The concentrations found for cadmium and lead ranged from 0.6 to 3.9 μg/100 g and 1.0 to 2.1 μg/100 g, respectively. Concentrations ranged between 0.5 and 3.3 mg/100 g for iron, 0.7 and 5.1 mg/100 g for zinc, 9 and 44 μg/100 g for selenium, 3.1 and 16.7 μg/100 g for manganese, 0.3 and 132 μg/100 g for copper and 0.9 and 3.2 μg/100 g for molybdenum. Differences found for the concentrations in meat from different species as well as between the individual meat cuts were notable for iron, zinc, selenium and copper. Manganese concentrations were found to vary unsystematically within muscles and species. Molybdenum concentrations were higher in chicken meat in comparison with the mammalian meats. The highest coefficients of variation were found for manganese (13% to 142%) and copper (13% to 224%), while the lowest was found for zinc (4% to 45%). In conclusion, in order to provide an accurate overview and to be able to calculate reliable dietary intakes, it is important to include the variability in food composition data.  相似文献   

4.
Trace element disturbance is often observed in hemodialysis patients. While trace element concentrations have been reported in blood samples from hemodialysis patients, they have not been well investigated in scalp hair. In the present study, 22 trace elemental concentrations were measured by inductively coupled plasma-atomic emission spectrometry in the scalp hair of 80 male hemodialysis patients and compared with those of 100 healthy male subjects. In hemodialysis patients, the concentrations of beryllium, arsenic, magnesium, chromium, manganese, iron, selenium, molybdenum, iodine, vanadium, and cobalt were significantly higher than those in healthy subjects, while lead, mercury, copper, germanium, and bromine were significantly lower than those in the former group. No significant differences were observed for lithium, aluminum, cadmium, zinc, boron, or nickel. There were significant positive correlations between the duration of hemodialysis and the magnesium and manganese concentrations. There was a significant negative correlation between cadmium concentration and the duration of hemodialysis. There were significant positive correlations between dialysis efficacy (Kt/V) and magnesium, manganese, zinc, and selenium concentrations. In conclusion, trace element concentrations of the scalp hair are different between hemodialysis patients and healthy subjects. Essential trace elements, such as magnesium, manganese, zinc, and selenium, may be affected by the duration of hemodialysis and Kt/V.  相似文献   

5.
Changes in essential trace elements and heavy metals may affect the atherosclerotic state of patients on maintenance hemodialysis (HD). The aim of the study was to evaluate the relation between the serum levels of some trace elements and heavy metals (iron, zinc, manganese, copper, magnesium, cobalt, cadmium, lead, and copper/zinc ratio) and carotid artery intima-media thickness (CIMT) in HD patients. Fifty chronic HD patients without known atherosclerotic disease and 48 age- and sex-matched healthy individuals were included in the study. The serum levels of trace elements (iron, zinc, manganese, copper, and magnesium) and heavy metals (cobalt, cadmium, and lead) were measured by Atomic Adsorption Spectrophotometer (UNICAM-929). CIMT was assessed by carotid artery ultrasonography. The serum levels of iron, zinc, and manganese were lower; levels of copper, magnesium, cobalt, cadmium, lead, and copper/zinc ratio were higher in HD patients compared to controls. CIMT in HD patients were higher than the control group (0.64?±?0.11 vs 0.42?±?0.05, p?相似文献   

6.
Lead and zinc poisoning have been recorded in a variety of bird species, including migrating waterfowl such as Canada Geese (Branta canadensis), at sites contaminated with mine waste from lead and zinc mines in the Tri-State Mining District, Kansas, Oklahoma, and Missouri, USA. The adverse health impacts from mine waste on these birds may, however, be more extensive than is apparent from incidental reports of clinical disease. To characterize health impacts from mine waste on Canada Geese that do not have observable signs of poisoning, four to eight apparently healthy birds per site were collected from four contaminated sites and an uncontaminated reference site, and examined for physical and physiologic evidence of metals poisoning. Tissue concentrations of silver, aluminum, arsenic, barium, cadmium, cobalt, chromium, copper, iron, magnesium, manganese, molybdenum, nickel, lead, selenium, thallium, vanadium, and zinc were determined by inductively coupled plasma mass spectroscopy. Adverse health effects due to lead were characterized by assessing blood δ-aminolevulinic acid dehydratase (ALAD) enzyme activity. Adverse effects associated with zinc poisoning were determined from histologic examination of pancreas tissues. Elevated tissue lead concentrations and inhibited blood ALAD enzyme activities were consistently found in birds at all contaminated sites. Histopathologic signs of zinc poisoning, including fibrosis and vacuolization, were associated with elevated pancreatic zinc concentrations at one of the study sites. Adverse health effects associated with other analyzed elements, or tissue concentrations indicating potentially toxic exposure levels to these elements, were not observed.  相似文献   

7.
In this study, we aimed to assess whether free-ranging wild canids are exposed to heavy metals in one of the most developed and populated regions of Brazil. Hair of 26 wild canids (maned wolves Chrysocyon brachyurus, crab-eating foxes Cerdocyon thous, and hoary foxes Lycalopex vetulus) from the Cerrado biome in Southeast Brazil were analyzed by spectrophotometry to detect cadmium, chromium, and lead, and also the essential copper, iron, manganese, and zinc traces. All samples showed traces of copper, iron, manganese, and zinc. Non-essential lead was detected in 57% (2.35 ± 0.99 mg/kg), and chromium in 88% (2.98 ± 1.56 mg/kg) of samples. Cadmium traces (detection limit 0.8 mg/kg) were not found. Crab-eating foxes had more copper, iron, and manganese in hair than maned wolves. Correlations among element levels differed between maned wolves and crab-eating foxes. Concentrations of chromium and lead were outstandingly higher than in wild canids from other areas. Addressing the causes of such levels and the impacts of the heavy metal pollution in Neotropical ecosystems is urgent for animal health and conservation purposes. We argue that heavy metal pollution should be considered as dangerous threats to wildlife health in Brazil and recommend hair sampling as a biomonitoring tool for heavy metals in Neotropical terrestrial mammals.  相似文献   

8.
TRACE-ELEMENT TOXICITIES IN OAT PLANTS   总被引:4,自引:0,他引:4  
Excessive amounts of nickel, cobalt, chromium, copper, zinc, manganese, molybdenum and aluminium in nutrient solutions supplied to oat plants in sand culture produce ( a ) chlorosis and ( b ) other symptoms specific to the element involved. The specific symptoms are distinct for each metal, although those of cobalt and nickel might be confused.
The toxic effects of nickel, cobalt, copper, zinc, manganese and molybdenum are associated with high concentrations of the element in the leaf tissue, but this is not always so with chromium and aluminium.
The toxic effects of nickel, chromium, copper and molybdenum are associated with a reduced nitrogen content of the plant. Nickel, cobalt, chromium, zinc and manganese increase the concentration of phosphorus in the tissue whilst aluminium decreases it, probably to a deficiency level.
Aluminium reduces the intensity of toxic symptoms produced by nickel—probably by reducing the uptake of nickel and phosphorus. Copper effectively reduces the leaf necrosis produced by nickel, but not the nickel content of the leaf tissue; it is suggested that one factor in nickel toxicity may be inhibition of one or more functions of copper. The other elements slightly increase chlorosis and some increase necrosis.
The order of activitjl of the elements in producing chlorosis is found to be Ni>Cu>Co>Cr>Zn>Mo>Mn. This order, which is related to that giving yield reduction and is similar to the order of stability of metal complexes, is discussed in relation to induced iron deficiency.  相似文献   

9.
Effect of metal ions on aflatoxin production byAspergillus parasiticus   总被引:2,自引:0,他引:2  
The effect of iron, copper, cobalt, cadmium, zinc, molybdenum, magnesium and manganese salts was studied on aflatoxin production in relation to mycelial mass. Iron, copper and cadmium salts decreased the aflatoxin production to different levels but a mixed trend was observed depending on salt concentration, with molybdenum, magnesium and manganese. Cobalt and zinc salts stimulated aflatoxin production at all concentrations studied. The maximum increase in aflatoxin production, 655% and 519% was observed in the presence of zinc sulfate and sodium molybdate, respectively. A negative correlation was observed between aflatoxin production and vegetative growth of fungus.  相似文献   

10.
A continuous flow of chromium into apples occurs throughout their growth. This ready movement of chromium into the apple is similar to that reported for essential trace elements such as boron, zinc, iron, copper, and manganese but differs from the restricted movement reported for mercury and cadmium.  相似文献   

11.
The lower six miles of the tidal portion of the Passaic River (Study Area) has long been heavily industrialized. The objectives of this study were to: quantify the present extent and magnitude of metals contamination in surface sediments in the Study Area, evaluate the contamination in the Study Area relative to a reference area and surrounding regional waterways, assess the potential for adverse effects to aquatic organisms, and identify spatial gradients in concentrations that may indicate potential point-sources of metals. We also examined the role of natural sediment characteristics in metals concentration variability. Study Area sediments were generally enriched in barium, cadmium, chromium, copper, lead, manganese, mercury, silver, selenium, and zinc relative to the reference area. Compared to available sediment quality benchmarks, the only metals in the Study Area presently at average concentrations sufficiently high to warrant concern about potential aquatic toxicity are lead, mercury, and zinc. Compared to the rest of the NY/NJ Harbor Estuary, the Study Area generally contains elevated levels of lead, manganese, silver, and zinc. Variability in metals concentrations can not be accounted for by TOC or percent fines. However, a substantial proportion of the spatial variability in a number of metals can be explained by normalization to either aluminum or iron.  相似文献   

12.
英德西南旅游区水源河流水质与浮游生物群落特征   总被引:1,自引:0,他引:1  
通过野外采样及实验室分析,调查了英德市西南旅游区水源河流上、中、下游的水质状况及浮游生物的多样性。结果表明,(1)英德市西南旅游区上、中、下游河段亚硝酸盐、氨、硝酸盐、总氮、镉、铅、铬、镍、铜、锌的含量低于国家标准,铝、钙、钴、铁、钼、硒的含量超过国家标准,而总磷、砷、镁、锰的含量在部份区段已超过国家标准;(2)浮游动物种类的个体数在整条河中以桡足类最多,上游通天岩中浮游动物个体数最多,下游碧落湖浮游动物多样性最低;此次调查总共发现68种浮游植物,其中主要集中在下游碧落湖,在中游碧落洞绿藻、蓝藻、硅藻总个体数最低,上游通天岩绿藻及甲藻总个体数最多,而下游碧落湖的蓝藻和硅藻的总个体数最多;(3)总氮、总磷、铅、钙、浮游动物Shannon-Weaver指数与浮游植物Shannon-Weaver指数从上游向下游增加,而锰与镍含量则成相反趋势。文中探讨了水中元素之间、元素与生物之间、浮游动植物之间的相互关系。本文对风景区水源的生态环境的研究风景区旅游资源开发与管理提供参考。  相似文献   

13.
Abnormal distributions of transition metals inside the brain are potential diagnostic markers for several central nervous system diseases, including Alzheimer’s disease (AD), Parkinson’s disease, dementia with Lewy bodies (DLB), bipolar disorders and depression. To further explore this possibility, the total concentrations of iron, zinc, copper, manganese, aluminum, chromium and cadmium were measured in post-mortem hippocampus and amygdala tissues taken from AD, DLB and Control patients. A statistically significant near fifty percent reduction in the total copper levels of AD patients was observed in both the hippocampus and amygdala. The statistical power of the hippocampus and amygdala copper analysis was found to be 86 and 74% respectively. No statistically significant deviations in the total metal concentrations were found for zinc, manganese, chromium or aluminum. Iron was found to be increased by 38% in AD amygdala tissues, but was unchanged in AD hippocampus tissues. Accounting for differences in tissue water content, as a function of both tissue type and disease state, revealed more consistencies with previous literature. To aid in the design of future experiments, the effect sizes for all tissue types and metals studied are also presented.  相似文献   

14.
The heavy metal resistance of yeasts isolated from sugary substrates such as orange, palm wine and pineapple and identified asSaccharomyces carlsbergensis andS. cerevisiae was studied. The yeast isolates were tested against different concentrations of cadmium, copper, manganese, silver and zinc salts ranging from 1 to 20 mmol/L. Local yeasts showed resistance to 3–15 mmol/L cadmium, 18–20 copper, 16–20 manganese, 1–9 silver and 16–19 for zinc. The significance of the results is discussed in relation to the effects of heavy metals on growth of microorganisms and selection of yeasts for the brewing industry in Nigeria.  相似文献   

15.
The concentration of trace elements in L-cells has been studied as a function of the trace metal content of the growth medium. Cells were cultured in synthetic media which contained varying trace amounts of the elements manganese, iron, cobalt, copper, zinc and molybdenum. The cellular concentration of the elements potassium, iron, copper and zinc were then determined. It was found that the cell accumulates trace metals at a different rate than they are made available. Deficiencies in zinc could be “induced” in the cell by increasing the concentration of iron, manganese and cobalt; cellular iron deficiencies were observed at larger medium concentrations of zinc, manganese, copper and cobalt. Trace metal uptake by the cell was seen to parallel the utilization by multicellular organisms.  相似文献   

16.
Abstract

Metal fractionation is a powerful tool for studying the mobility, bioavailability and toxicity of metals in sediments and soils. A seven-step sequential extraction technique was used to determine the potential mobility of selected heavy metals (Fe, Mn, Zn, Cu, Pb, Cd and Ni) in the sediments of Lake Naivasha. Results indicate that residual fraction was the most important phase for the elements Fe, Mn, Cu and Zn. However, Pb and Cd are highly enriched in the non-residual phases. Nickel on the other hand was distributed evenly between the non-residual and the residual fractions.

The total concentrations of the heavy metals suggested a decreasing order of iron ?> manganese ? zinc > nickel > copper ? lead > cadmium. However, the detailed sequential extraction data indicated an order of release or mobility of cadmium > lead ? nickel ? zinc > manganese > copper > iron. The high percentage of Cd and Pb in the mobile fractions suggests high bioavailability of these two elements in the study area and maybe a pointer to anthropogenic input of the two elements in the study area.  相似文献   

17.
BackgroundEnvironmental factors, including elemental homeostasis, have not been studied sufficiently in neurodevelopmental disorders (NDD). This study aims to compare the status of 13 elements in blood and deciduous teeth dentine of children having an autism spectrum disorder or attention deficit hyperactivity disorder with typically developing controls.MethodsElements including calcium, phosphorus, magnesium, iron, zinc, copper, chromium, manganese, mercury, lead, cadmium, molybdenum, and strontium in both deciduous teeth and blood were analyzed by inductively coupled plasma mass spectrometry.ResultsStrontium levels in both blood and teeth samples were found to be significantly lower in the NDD group. Additionally, blood cadmium and mercury levels, and copper/zinc ratio were higher in the NDD group.ConclusionsOur results warrant further investigation in a large series of NDD examining symptom levels and genetic variations associated with elemental homeostasis.  相似文献   

18.
The distribution of silver, arsenic, cadmium, cobalt, chromium, copper, iron, manganese, nickel, lead, selenium and zinc binding to species with different molecular weight in aqueous extract of krill was studied by on-line size-exclusion chromatography (SEC)/inductively coupled plasma mass spectrometry (ICP-MS). The extract was fractionated in three fractions with different molecular weight (MW) ranges (>20,000 relative molecular mass (rel. mol. mass), 2000-20,000 rel. mol. mass and <2000 rel. mol. mass), which were further analyzed by SEC with columns having different optimum fractionation ranges in order to obtain more detailed information about the MW distribution of the elements. Various distribution profiles for the target elements among different MW ranges were observed. The results obtained indicated that manganese, zinc, silver, cadmium and lead species were mostly distributed in the higher MW range (>20,000 rel. mol. mass). In the case of chromium, iron, cobalt, arsenic and selenium, most of them bind to species with lower MW (<2000 rel. mol. mass). Only copper and nickel species was predominantly present in middle MW range (2000-20,000 rel. mol. mass). Further speciation of arsenic compounds in the small MW fraction was carried out with anion exchange chromatography (AEC) coupled with ICP-MS. The results showed that the dominant arsenic species in this fraction is As(III) (63% of extractable arsenic), while As(V) (13%) and two unknown arsenic species (19% and 5%, respectively) are present in lower amounts.  相似文献   

19.
The effects of the elements zinc, manganese, iron, copper, molybdenum, and vanadium, added in various salt forms, on mycelial weights and aflatoxin B1 accumulation in the mycelium of Aspergillus flavus were investigated in liquid shake cultures. Ammonium heptamolybdate, when added to a complete medium at concentrations of 50-100 mg/L, appreciably reduced aflatoxin B1 accumulation without affecting growth of the fungus. Sodium molybdate and sodium monovanadate also reduced aflatoxin B1 yields without affecting mycelial growth but to a lesser extent. The addition of zinc sulphate stimulated aflatoxin B1 production in all media used. The influence of the other trace elements on aflatoxin production depended on the level of trace elements present in the basal medium. In general, manganese chloride had a stimulatory effect, whereas copper sulphate depressed yields. Mycelial levels of aflatoxin had peaked and then declined before mycelial dry weights had reached maximum. High yields of aflatoxin B1 were obtained in media having a final pH as low as pH 2.8.  相似文献   

20.
The quality of the diet of obese children is poor. Eating habits may alter micronutrient status in obese patients. In this study, we determined the serum levels of selenium, zinc, vanadium, molybdenum, iron, copper, beryllium, boron, chromium, manganese, cobalt, silver, barium, aluminum, nickel, cadmium, mercury, and lead in obese Turkish children. Thirty-four obese and 33 healthy control subjects were enrolled in the study. Serum vanadium and cobalt levels of obese children were significantly lower than those of the control group (0.244 ± 0.0179 vs. 0.261 ± 0.012 μg/l, p < 0.001, and 0.14 ± 0.13 vs. 0.24 ± 0.15 μg/l, p = 0.011, respectively). There was no significant difference between groups regarding the other serum trace element levels. In conclusion, there may be alterations in the serum levels of trace elements in obese children and these alterations may have a role in the pathogenesis of obesity.  相似文献   

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