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PubMed2005

Development of a procedure for the sequential extraction of substances binding trace elements in plant biomass.

This work investigates how the amounts of some important substances in a plant, and their behaviour inside the plant, depend on the levels of stress placed on the plant. To this end, model plant spinach (Spinacia oleracea L.) was cultivated on soil treated with sewage sludge. The sewage sludge contained various trace elements (As, Cd, Cu, Zn), and the uptake of these trace elements placed the plant under stress. Following this, a sequential extraction procedure was employed to determine the levels and distributions of trace elements within the most important groups of compounds present in the spinach plants. Since the usual five-step sequential extraction procedure provides only general information on the distributions of elements within individual groups of organic compounds, due to the wide range of organic compounds within the individual fractions, this scheme was extended and improved through the addition of two solvent extraction steps-a butanol step (between the ethyl acetate and methanol solvent steps) and an H(2)O step (after the methanol+H(2)O solvent step). The distributions and levels of the trace elements within the main groups of compounds in spinach biomass was investigated using this new seven step sequential extraction (water free solvents: petroleum ether (A) --> ethyl acetate (B) --> butanol (C) --> methanol (D) --> water solvents: methanol+H(2)O (1+1; v/v) (E) --> H(2)O (F) --> methanol+H(2)O+HCl (49.3+49.3+1.4; v/v/v) (G)). The isolated fractions were characterized using IR spectroscopy and the trace element contents were determined in the individual fractions. Lipophilic compounds with low contents of Cd, Cu and Zn were separated in the first two fractions (A, B). Compounds with higher As contents (11.5-12.8% of total content) were also extracted in the second fraction, B. These two fractions formed the smallest portion of the isolated fractions. Low molecular compounds from secondary metabolism and polar lipids were separated in the third (C) and fourth (D) fractions, and high molecular compounds (mainly polypeptides and proteins) separated in the fifth and sixth fractions (E, F). The addition of the H(2)O solvent step was particularly useful for separating compounds that have a significant impact on trace element bounds. The methanol fraction was dominant for all treatments, and a significant decrease in the spinach biomass separated in this fraction was observed when the soil was treated with sewage sludge. Most of the As (35.5-38.8% of total content), Cu (45.0-51.6%) and Zn (39.8-47.2%) was also determined in this fraction. The G fraction (obtained after acid hydrolysis) contained polar compounds. Most of the Cd was also found in this fraction, as was a significant amount of Zn. Non-extractable residues formed the last fraction (polysaccharides, proteins).

Biomass↗
PubMed1988

Trace element content in drinking water of nasopharyngeal carcinoma patients.

Chinese in the Xiangxi region of Hunan province in China have a high incidence of nasopharyngeal carcinoma (NPC). For analyzing the relation between NPC and trace elements, the concentrations of 7 trace elements in drinking water (well water) of high- and low-incidence areas were measured (75 samples). The results showed that the concentrations of Ni, Zn and Cd in drinking water of high-incidence areas were significantly higher than those in low-incidence areas. Especially, the Ni level in drinking water had a significant positive correlation with NPC mortality. These observations are consistent with earlier studies. We also found a highly positive correlation between Ni/pH value in drinking water and NPC mortality. This suggests that only considering the ion concentration in drinking water is not enough, we should also pay attention to the pH of the drinking water when we study the relation between NPC and trace elements. Because the pH of the medium can strongly affect trace element chemical characteristics and its metabolic state in living systems, the M/pH (M, metal concentration) may be an important factor worthy of further research.

Humans↗
PubMed2003

Genetically modified plants for improved trace element nutrition.

Deficiencies of iron and zinc are common worldwide. Various strategies have been used to combat these deficiencies including supplementation, food fortification and modification of food preparation and processing methods. A new possible strategy is to use biotechnology to improve trace element nutrition. Genetic engineering can be used in several ways; the most obvious is to increase the trace element content of staple foods such as cereals and legumes. This may be achieved by introduction of genes that code for trace element-binding proteins, overexpression of storage proteins already present and/or increased expression of proteins that are responsible for trace element uptake into plants. However, even very high levels of expression may not substantially increase the iron and zinc contents unless many atoms of trace elements are bound per protein molecule. Another possibility is to introduce a protein that specifically enhances trace element absorption even in the presence of naturally occurring inhibitors, thus improving bioavailability. Genetically modifying plants so that their contents of inhibitors of trace element absorption such as phytate are substantially reduced is another approach. Increasing the expression of compounds that enhance trace element absorption such as ascorbic acid is also a possibility, although this has received limited attention so far. Iron absorption may be increased by higher ascorbic or citric acid content but require overexpression of enzymes that are involved in the synthetic pathways. Finally, a combination of all of these approaches perhaps complemented with conventional breeding techniques may prove successful.

Absorption↗
PubMed1994

Trace element content in breasts with fibrocystic disease.

The trace elements antimony, bromine, cesium, cobalt, iron, rubidium, scandium, strontium and zinc were determined by instrumental neutron activation analysis in breast tissue samples with fibrocystic disease and in samples with fibroadenoma tumors. The histological lesions of each breast sample with fibrocystic disease were recorded, and a statistical analysis of the lesions in combination with the determined trace elements was carried out. The results showed that the element mean values in fibroadenoma tumors are higher than those of fibrocystic disease. Some other remarkable results of statistical examination are also presented.

Breast↗
PubMed2002

Trace element contamination in benthic macroinvertebrates from a small stream near a uranium mill tailings site.

Direct measurement of the accumulation of non-radioactive trace elements in aquatic biota near uranium mining or processing sites has been relatively rare, with greater focus on the radiological activity in the adjacent soils and groundwater. To evaluate the potential ecological concern associated with trace elements at a former uranium mill site in southeastern Utah, benthic macroinvertebrates were collected and analyzed for 17 trace elements from multiple locations within a small on-site stream, Montezuma Creek, and a nearby reference stream. Key questions of this study relate to the spatial and temporal extent of contamination in aquatic biota, the potential ecological risks associated with that contamination, and the usefulness of benthic macroinvertebrates as a monitoring tool at this site. Composite samples of similar macroinvertebrate taxa and functional feeding groups were collected from each site over a two year period that was representative of normal and dry-year conditions. In both years, mean concentrations of arsenic, molybdenum, selenium, and vanadium were significantly higher (a factor of 2-4 times: P < 0.05) in macroinvertebrates collected from one or both of the two Montezuma Creek sites immediately downstream of the mill tailing site in comparison to concentrations from reference locations. Mean uranium concentrations in invertebrates immediately downstream of the mill site were more than 10 times higher than at reference sites. The site-to-site pattern of contamination in Montezuma Creek invertebrates was similar in 1995 and 1996, with mill-related trace elements showing a downstream decreasing trend. However, nine of seventeen contaminant concentrations were higher in the second year of the study, possibly due to a higher influx of deep groundwater during the drier second year of the study. A preliminary assessment of ecological risks, based on the benthic macroinvertebrate bioaccumulation data, suggests that aquatic and terrestrial population risks are low. Benthic macroinvertebrates appeared to be sensitive integrators of trace element inputs to the aquatic environment from a former uranium mill tailing site, and provided useful spatial and temporal patterns of contamination not easily obtained using conventional surface water or groundwater measures.

Animals↗
PubMed2001

Comparative uptake behavior of trace elements in adult and suckling rat lens.

The multitracer technique was applied to the determination of the uptake of trace elements in the lenses of adult and suckling rats to investigate the transport mechanisms of trace elements during developmental maturation. Be, Sc, V, Mn, Fe, Co, Zn, As, Se, Rb, Sr, Y, Zr, Ru and Rh accumulate in adult and suckling rat lenses. The rates of uptake of trace elements differ among each species and also differ between adult and suckling rat lenses. The uptakes of Fe and Sr are greater in adult rat lenses, while the uptakes of Se and Rb are greater in suckling rat lenses. High concentrations of Zn are transported into the lenses of both adult and suckling rats in comparison with other elements, and the content of Zn in suckling rat lens is higher than in adult lens. The present study suggests that different mechanisms depending on the stage of development act to transport trace elements into lenses.

Animals↗
PubMed1983

Trace element concentrations in commonly used intravenous fluids.

The concentrations of several essential trace elements in various intravenous fluids commonly used in South Africa were measured. With the exception of 4% human serum albumin and fresh freeze-dried plasma (FDP), intravenous fluids contained minimal amounts of essential trace elements. Although FDP contained significant quantities of zinc, copper, iron and chromium, the common practice of giving patients on total parenteral nutrition 1-2 units per week will not fulfil the recommended daily requirements. Additional trace element supplements should therefore be given intravenously to these patients.

Humans↗
PubMed2001

The use of transgenic plants in the bioremediation of soils contaminated with trace elements.

The use of plants to clean-up soils contaminated with trace elements could provide a cheap and sustainable technology for bioremediation. Field trials suggested that the rate of contaminant removal using conventional plants and growth conditions is insufficient. The introduction of novel traits into high biomass plants in a transgenic approach is a promising strategy for the development of effective phytoremediation technologies. This has been exemplified by generating plants able to convert organic and ionic forms of mercury into the less toxic, volatile, elemental mercury, a trait that occurs naturally only in some bacteria and not at all in plants. The engineering of a phytoremediator plant requires the optimization of a number of processes, including trace element mobilization in the soil, uptake into the root, detoxification and allocation within the plant. A number of transgenic plants have been generated in an attempt to modify the tolerance, uptake or homeostasis of trace elements. The phenotypes of these plants provide important insights for the improvement of engineering strategies. A better understanding, both of micronutrient acquisition and homeostasis, and of the genetic, biochemical and physiological basis of metal hyperaccumulation in plants, will be of key importance for the success of phytoremediation.

Biodegradation, Environmental↗
PubMedDate not supplied

Antioxidant enzymes and trace elements in hemodialyzed patients.

Antioxidant enzymes together with trace elements in 26 patients with chronic renal failure treated with hemodialysis and 25 healthy subjects were investigated. Superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSHPx) in plasma and erythrocytes were examined immediately before and after hemodialysis. The results are summarized as follows: 1. A significant decrease in plasma SOD, CAT, and GSHPx and erythrocyte GSHPx were found in patients before hemodialysis. 2. Erythrocyte CAT and GSHPx were significantly lower in the patients after hemodialysis than in the controls. 3. Plasma GSHPx was significantly higher after a single hemodialysis than before hemodialysis. 4. A good correlation between erythrocyte SOD and copper (Cu) in patients before hemodialysis was found. 5. A good correlation of GSHPx in erythrocytes and plasma was found before hemodialysis, whereas an even better correlation was found after hemodialysis. 6. Abnormalities of trace elements were found in hemodialyzed patients. 7. There is indirect evidence for increased oxidizing stress in uremic patients with hemodialysis. Dialysis treatment may improve some abnormalities (e.g., Hb, P), but may also induce some deleterious effects of free radicals or lipid peroxidation.

Adult↗
PubMed1983

The role of soil and plant metabolic processes in controlling trace element behavior and bioavailability to animals.

Metabolic and physiological processes play important roles in regulating the transfer and behavior of trace elements in the soil/plant/animal system. The behaviors of Ni, Cd, Cr, T1, Np, Pu and Tc are used to illustrate important aspects of these processes. Microbial metabolism has both indirect and direct effects on trace element solubility in soils. Once non-nutrient trace elements are solubilized, the ability of plant roots to actively accumulate them is dependent on chemical activity of the element in soil solution, the presence of competing ions and the redox potential and absorption capacity of the root. After absorption in the plant, trace elements are translocated, metabolized and stored; fate and behavior varies with the properties of the element, but is generally analogous to nutrient elements. These processes can dramatically affect the availability of individual elements to animals consuming plants.

Animals↗
PubMed2005

Specific accumulation of 20 trace elements in great cormorants (Phalacrocorax carbo) from Japan.

This study is to elucidate the specific accumulation of 20 trace elements in tissues/organs of great cormorants from two different colonies (Lake Biwa and Mie) in Japan. In the body distribution of trace elements, some elements revealed tissue-specific accumulation such as most of the burden of Mo, Ag and Cd in liver, Tl and Cd in kidney, Cu, Rb and Cs in muscle, and V, Sr and Ba in bone. Gender-related variation was not observed in both populations for most of the trace elements, except for higher hepatic Sr in males from Lake Biwa. Hepatic V, muscular Hg and Tl, and Cd in liver, kidney and muscle increased with growth. Comparison of trace element levels in tissues between the two colonies showed that Cr, Rb, Sr, Cd, Cs, Ba and Tl levels were higher in Lake Biwa than in Mie, whereas Zn, Co and Hg in Mie samples were greater than Lake Biwa. Variations of elemental levels in stomach contents also showed similar patterns, thus, showing that dietary sources tended to be the main factor for these regional variations. Toxic Hg and Cd concentrations in the liver of cormorants from the two colonies were lower than those from other areas, implying relatively low exposure to these metals in the present study sites. Concentrations of V, Co, Ag, Cd, Cs, Hg, Tl, Pb and Bi in liver remained more or less at the same level between 1993 and 2003, while hepatic Cr, Mn, Cu, Zn, Se, Rb, Sr and Ba showed apparent decrease, which might be related to the biological factors.

Animals↗
PubMed2004

Chemical characteristics of aerosols at coastal station in Hong Kong. II. Environmental behavior of trace elements during the April 1995 to April 1996.

An one-year of sampling aerosol program was carried out during the period of April 1995 to April 1996 at coastal region, Cape D'Aguilar, in Hong Kong. The trace element composition of aerosol particles (TSP and PM10) were measured and analyzed by using the Instrumental Neutron Activation Analysis (INAA) and Inductive Couple Plasma-Mass Spectrometry (ICP-MS) techniques. The results showed that the polluted elements such as: V, Zn, As, Pb, Cd, Sb, I, Se, Bi, with high enrichment factor (E. F) values, are derived from anthropogenic sources, while Sc, Al, Fe, Mn, Sm, La, Sr are less than 10 in E. F, these elements are related the crust and soil. The concentration of the trace elements are present seasonal variation i.e. summer low and winter high, whereas the V or noncrustal V (V*) present summer high and winter low, this phenomenon might be explained by local or regional oil combustion sources. Use three type of elemental ratio, e.g. La/Sm, Mn*/V* and Bi/Al indicate that both TSP and PM10 of La/Sm ratios are mainly related to soil and dust, Mn*/V* are probably represent fossil combustion and Bi/Al are possibly associated with refuse incineration, ferromanganese alloys and aluminum production. The varimax rotation factor analysis for trace elements was performed. By means of the absolute principal component analysis (APCA) and multiple regression, the contribution of trace elements to possible sources and overall means of trace elements were estimated. The results showed that the present station is impacted by the anthropogenic species, although the quantities are different during the summertime and wintertime.

Air Pollutants↗
PubMed2006

Exposure assessment for trace elements from consumption of marine fish in Southeast Asia.

Concentrations of 20 trace elements were determined in muscle and liver of 34 species of marine fish collected from coastal areas of Cambodia, Indonesia, Malaysia and Thailand. Large regional difference was observed in the levels of trace elements in liver of one fish family (Carangidae): the highest mean concentration was observed in fish from the Malaysian coastal waters for V, Cr, Zn, Pb and Bi and those from the Java Sea side of Indonesia for Sn and Hg. To assess the health risk to the Southeast Asian populations from consumption of fish, intake rates of trace elements were estimated. Some marine fish showed Hg levels higher than the guideline values by U.S. Environmental Protection Agency and Joint FAO/WHO Expert Committee on Food Additives (JECFA). This suggests that consumption of these fish may be hazardous to the people.

Animals↗
PubMed2001

[Analysis on the trace element and amino acid content in xinjiang 6 series Rhodiola L. plant].

Trace elements Na, K, Mg, Ca, Mn, Fe, Cu, Zn, Se and 20 kinds of amino acid in Xinjiang 6 series of Rhodiola's root and rootstalk were measured. The result shows that contents of 9 kinds of trace elements in them are different. They contain from 8 to 18 kinds amino acid, and also contain from 3 to 7 kinds of indispensable amino acid respectively. Rhodiola rosea L. contains most kinds of amino acid among six kinds of Rhodiola L. in Xingjiang, and contents of trace elements in it are also moderate, so it is fittest to be a nutrious chinese traditional and herbal drug of six kinds of Rhodiola L. in Xingjiang.

Amino Acids↗
PubMed2000

Critical examination of trace element enrichments and depletions in soils: As, Cr, Cu, Ni, Pb, and Zn in Swiss forest soils.

The aim of this study was to obtain an overview of trace element concentrations in Swiss forest soils and to critically assess the measured values with respect to anthropogenic input vs. lithogenic background. Twenty-three sites were selected which represent a broad range of natural forest sites, bedrock material and soil types of Switzerland. At each site, samples were collected from all genetic soil horizons down to a C or B/C horizon. Total concentrations of As, Cr, Cu, Ni, Pb, and Zn in all samples were determined by X-ray fluorescence spectrometry. There were distinct differences in the geological background values estimated from the concentrations measured in the samples from the lowest soil horizon. Background concentrations for Cr and Ni were lowest in granite and gneiss, whereas Pb and Zn were highest in limestone and marl. Enrichment or depletion of the trace elements was assessed using Zr as reference element. Within the same profile, the six trace elements showed completely different enrichment/depletion patterns with depth. The various natural processes and anthropogenic inputs that can lead to these patterns are critically discussed. Based on this critical assessment, pollution of the investigated forest soils was found to be most severe for Pb and Zn and to a somewhat lesser extent for As and Cu, whereas anthropogenic input of Cr and Ni seems to be less important. The data suggest that a critical evaluation of enrichment factors is a better tool to assess soil pollution with trace elements than the use of maximum allowable concentrations (MAC) for topsoil samples. The enrichment factors calculated as described here consider the effects of geological variation on metal abundances whereas the MAC does not. In order to obtain an estimate of soil solution concentrations, water extracts of the samples collected from a subset of 10 soil profiles were analyzed for the same trace elements. Solubility of all elements generally decreased with soil depth. An exception was Cr, Cu, and Ni solubility in the humus layer, which was lower than in the underlying mineral horizon. For all elements, solubility was higher for the collective of soil samples depleted in this element when compared to the samples, in which the element was enriched.

Arsenic↗
PubMed2005

Interannual patterns of variation in concentrations of trace elements in arms of Octopus vulgaris.

Concentrations of essential (copper, iron, manganese, selenium, and zinc) and non-essential (arsenic, cadmium, mercury, and lead) trace elements were measured in arms of Octopus vulgaris. The cephalopods were sampled from commercial fishery landings at two sites on the Portuguese coast in spring 2002 and 2003. Mercury was determined using an Advanced Mercury Analyser Spectrophotometer (AMAS) and other trace elements were measured using inductively coupled plasma-atomic emission spectrometry (ICP-AES). Since high levels of arsenic were detected, identification of the forms present was carried out using high performance liquid chromatography (HPLC) followed by ICP-MS. Mean concentrations of trace elements analysed were in the following order: As > Zn > Fe > Cu >> Cd > Pb > Se > Mn >> Hg. The results of speciation of arsenic demonstrate that virtually all arsenic was in the arsenobetaine form, which is the less toxic form. The concentrations of several trace elements were generally high in samples from Viana in 2002. Cadmium concentrations were above the legal limit for human consumption in samples from Viana in 2002 and two of these animals also had lead concentrations that exceeded legal limits. Mercury appeared in all samples but levels were within legally defined safe limits. No relationship was detected between trace element concentrations and size or maturity of octopus.

Analysis of Variance↗
PubMed1988

Accumulation of trace elements in the fruiting bodies of macrofungi in the Krusné Hory Mountains Czechoslovakia.

The concentrations of some trace elements (Pb, Cd, Cu, Fe, Mn, Zn, Co, Ni) were determined in fruiting bodies of 20 fungal species from seven families (order Agaricales, Basidiomycetes) growing in the Krusné Hory Mountains, Czechoslovakia, where the air pollution is characterized as moderate. Samples were collected from three stands: a spruce forest, the waterlogged margin of a peat bog, and the peat bog itself. The biomass of fruiting bodies of all macrofungi was determined simultaneously. The trace element concentrations varied among trophic groups of fungi: saprophytic species (S) and those parasitic on Sphagnum (Sph) exhibited the highest concentrations, while wood-decomposing (Wd) species displayed the lowest. Several species mycorrhizal with spruce (Ms), such as Amanita umbrinolutea, Russula ochroleuca, and Xerocomus badius, also attained higher concentrations than were found for other mycorrhizal fungi. The trace element concentrations were higher in the caps than in the stems of the fungi. The fraction of trace metals retained by the biomass of fruiting bodies of fungi with respect to annual fallout is estimated at 1 0/00. Factors affecting fungal uptake of trace elements are discussed.

Air Pollutants↗
PubMed1999

Effect of antioxidant trace elements on the response of cardiac tissue to oxidative stress.

It is now well established that several trace elements, because of their involvement in the catalytic activity and spatial conformation of antioxidant enzymes, may contribute to the prevention of oxidative stress such as occurs upon reperfusion of ischemic tissue. The aim of this paper is (1) to review the role of these trace elements (Cu, Mn, Se, and Zn) in antioxidant cellular defenses in the course of post-ischemic reperfusion of cardiac tissue, (2) to provide experimental data suggesting that variations in trace element dietary intake may modulate the vulnerability of cardiac tissue to ischemia-reperfusion, and (3) to discuss in more detail the effect of Mn ions, which seem to play a special protective role against reperfusion injury. Some results obtained from experiments in animal models of myocardial reperfusion have shown that the dietary intake of such trace elements can modulate cardiac activity of antioxidant enzymes and, consequently, the degree of reperfusion damage. In addition, experimental data on the protective effects of an acute treatment with Mn are presented. Finally, experimental evidence on the protective role of salen-Mn complexes, which exhibit catalytic SOD- and CAT-like activities against reperfusion injury, are described. These complexes should be of considerable interest in clinical conditions.

Animals↗