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1.
Trace metals are components of releases to air emitted by copper and zinc production facilities in Canada. Six metals (copper, zinc, nickel, lead, cadmium, and arsenic) are examined as part of an overall environmental assessment of these releases. Estimates of metal deposition rates to soils and surface waters were derived from monitoring data in the vicinity of the production facilities and also through dispersion modelling studies. Fate and transport modelling of the metals deposited allowed an estimation of critical loads. Estimated annual deposition rates were compared with 25th-percentile critical loads typically representative of effects on sensitive organisms under 25% of conditions in sandy soils or circumneutral to acidic lake waters. The results of the comparison suggest that there is a potential for adverse effects on aquatic and/or soil-dwelling organisms from exposure to steadystate concentrations of metals in the vicinity of copper and zinc production facilities. Approaches of particular significance in these assessments include probabilistic estimation of critical loads for metals, allowance for the speciation of metals defining the bioavailable fraction and limiting critical effect levels to the high end of natural background metal concentrations.  相似文献   

2.
Five heavy metals detected in distillery waste were lead (1.0–8.8 μg/ml), copper (1.7–15.7 μg/ml), zinc (3.1–11.8 μg/ml), iron (36.0–43.5 μg/ml), and manganese (3.0–5.1 μg/ml). Their toxicity to biomethanogenesis in a synthetic medium containing 1% sodium acetate, propionate, or butyrate was measured by batch fermentation, after cultivating the bacterial biomass semicontinuously. Lead, copper, and zinc in decreasing order were found to be toxic to biomethanogenesis. Lead at the concentration of 10 μg/ml completely stopped methane production. Iron did not produce any notable change in the process while manganese stimulated the rate of methane production. The toxicity of lead, copper, and zinc to methanogenic bacteria and methane production was dose-dependent but the growth of acetogenic bacteria was impaired at higher concentrations (2.5–10.0 μg/ml) of lead, copper, and zinc. Manganese stimulated the growth of only methanogenic bacteria, but not that of non-methanogenic bacteria or acetic acid production. The reduction in the synthesis of acetic acid via butyrate was more in the presence of these three metals than the synthesis of this acid via propionate.  相似文献   

3.

The ban on the use of TBT-based antifouling paints for boats under 25 m in length has lead to a search for new non-toxic antifoulants. One of the most promising alternative technologies to heavy metal based antifouling paint is the development of antifouling coatings whose active ingredients are naturally occurring compounds from marine organisms. This is based on the principle that marine organisms also face the problem of the presence of epibionts on their own surfaces. In this study, the antifouling activity of a series of aqueous, ethanolic and dichloromethane extracts from thirty algae from the North East Atlantic coast was investigated. The extracts were tested in laboratory assays against species representative of two major groups of fouling organisms, viz . macroalgae and microalgae. The activity of several extracts was comparable to that of heavy metals and biocides (such as TBTO and CuSO 4 ) currently used in antifouling paints and their lack of toxicity with respect to the larvae of oysters and sea urchins suggests a potential for novel active ingredients.  相似文献   

4.
5.
The cadmium, zinc, lead and copper concentrations in benthic invertebrates and sediment were determined during two consecutive winters in the Maarsseveen Lakes system. A sequential extraction procedure was applied to estimate the bioavailability of the trace metals in the sediment. Based on the trace metal analyses of organisms and sediment, it is concluded that the Maarsseveen Lakes system has background levels of cadmium, zinc, lead and copper. As the majority of metals was present in geochemically more stable sediment phases, the sequential extractions provided limited additional information on trace metal bioavailability.  相似文献   

6.
Different metal carboxylate complexes are prepared by reactions of manganese (+2) acetate, copper (+2) acetate, zinc (+2) acetate and cadmium (+2) acetate with p-phenylenediacetic acid under ambient condition with or without a nitrogen donor ligands and each of them are characterized by conventional spectroscopic techniques along with crystallography.  相似文献   

7.
The speciation of cadmium, lead, copper, zinc, manganese and iron into exchangeable, carbonate, reducible and organic bound fractions was studied in sediments from coastal and freshwater environments in Ghana. This was relevant as the species in which metals are stored within specific sediment components is important in determining their impact on the environment. For both coastal and inland sediments, a higher percentage of cadmium was associated with the more available exchangeable and carbonate fractions, while iron, zinc and manganese were mainly associated with the reducible and organic fractions. Lead and copper were found to have the greatest ability to form different species in the samples examined and were more evenly associated with all the fractions. The metals generally showed more ability to form different species in inland freshwaters than in coastal relatively saline waters. However, differences between inland and coastal waters were based more on whether the environments were oxidising or reducing than on whether they were fresh or saline. The metals may be divided into three groups of high mobility consisting of lead and copper; moderate mobility made up of cadmium, manganese and zinc; and low mobility, represented by iron.  相似文献   

8.
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   

9.
The Gulf of Paria is bordered by both Trinidad and Venezuela, from which various metallic pollutants and other contaminants can originate. The Gulf is still a significant source of fish, crabs and shellfish for human consumption to both countries, where concerns over the quality of this marine environment have been long expressed but never properly addressed. In addition, the circulatory current patterns in the Gulf ensure that contaminants originating from either country are likely to affect both countries eventually. Heavy metals were determined in oysters (Crassostrea rhizophorae and C. virginica), green mussels (Perna viridis) and sediments from the Gulf of Paria. Samples were obtained at four sites in Trinidad and three sites in Venezuela in the Gulf of Paria, in addition to comparative samples collected from three sites on the north coast of Venezuela. Edible tissues of twelve shellfish from each location were blended and aliquots digested with concentrated nitric acid, for extraction of cadmium, chromium, copper, lead, nickel and zinc. The solutions were analysed by flame atomic absorption spectroscopy. Mercury was extracted with a mixture of nitric, hydrochloric and sulphuric acids and determined by cold vapour atomic absorption. Sediments were oven-dried at 60'C, before being similarly extracted. Results showed that mercury in sediments at all sites in Trinidad and Venezuela exceeded NOAA and Canadian sediment quality guidelines, while cadmium, copper, nickel, lead and zinc also exceeded these guidelines at several sites. Heavy metal levels in oysters and green mussels varied widely with location. However, oysters from the Gulf of Paria contained significantly higher mean levels of cadmium, copper, nickel and zinc than those from the north coast of Venezuela, but this difference was not apparent in mussels. Cadmium, mercury and zinc in sediments were significantly correlated with those of mussels, but not of oysters, in which copper and zinc at several sites in the Gulf of Paria exceeded local maximum permissible levels (Cu = 20 microg g(-1) wet wt; Zn = 50 microg g(-1) wet wt) for human consumption. These findings indicate that while mussels may be better biological indicators of heavy metal pollution in sediments than oysters, the latter may provide copper and zinc contamination. Further research is needed to determine the most appropriate biological indicators of heavy metal and other pollutants in the local marine environment and to develop protocols for their use.  相似文献   

10.
In a semicontinuous fermentation system, biomethanation of diluted spent wash (DW, initial COD 25–27 g/l) resulted in only 0.2 l/l of methane production in 20 d. Two capsular Gram-negative strains of bacteria were used for adsorption of heavy metals such as lead, copper, and zinc from spent wash. Strain I removed 64 % of the lead in 1 h and 82% of the copper in 2 h, while strain II removed 76% of the zinc in 2 h. The diluted spent wash from which heavy metals were removed was supplemented with synthetic medium and an acidophilic strain of Candida sp. This treatment improved methanogenesis. In 12 d, 4.9 l/l of biogas containing 63% methane was produced.  相似文献   

11.
Effect of ACTH and zinc acetate subcutaneous injection on the trace metals in liver and spleen was investigated in male Wistar rats. Iron, copper, zinc and manganese in liver, and iron, copper and zinc in spleen were analyzed by AAS method. The iron, copper and zinc levels in liver, and iron levels in spleen showed a significant decrease at 1-1 h 30 min after administration of 30 UI of ACTH but values returned to normality or showed slightly higher levels at 4 h 30 min-7 h 45 min. Zinc acetate injection only elicited an increase in liver and spleen zinc levels. Results are discussed in relation with results given in previous papers.  相似文献   

12.
The present study reports the mixed culture acidogenic production of biohydrogen and carboxylic acids (CA) from brewery spent grains (BSG) in the presence of high concentrations of cobalt, iron, nickel, and zinc. The metals enhanced biohydrogen output by 2.39 times along with CA biosynthesis by 1.73 times. Cobalt and iron promoted the acetate and butyrate pathways, leading to the accumulation of 5.14 gCOD/L of acetic and 11.36 gCOD/L of butyric acid. The production of solvents (ethanol + butanol) was higher with zinc (4.68 gCOD/L) and cobalt (4.45 gCOD/L). A combination of all four metals further enhanced CA accumulation to 42.98 gCOD/L, thus surpassing the benefits accrued from supplementation with individual metals. Additionally, 0.36 and 0.31 mol green ammonium were obtained from protein‐rich brewery spent grain upon supplementation with iron and cobalt, respectively. Metagenomic analysis revealed the high relative abundance of Firmicutes (>90%), of which 85.02% were Clostridium, in mixed metal‐containing reactors. Finally, a significant correlation of dehydrogenase activity with CA and biohydrogen evolution was observed upon metal addition.  相似文献   

13.
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   

14.
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   

15.
Aquatic organisms take up heavy metals from surrounding environments which accumulate in their body tissues. In the region of Auckland, New Zealand, the heavy metals, copper (Cu), lead (Pb) and zinc (Zn) are the primary sediment contaminants of concern. Previous investigations have revealed adverse effects of Cu and Zn, but not of Pb, on estuarine infauna and a higher sensitivity of the deposit-feeding bivalve Macomona liliana than the suspension-feeding bivalve Austrovenus stutchburyi to these metals. In order to further examine the bioavailability of Cu, Pb and/or Zn and their interactive effects, bioaccumulation of Cu, Pb and Zn was measured in M. liliana and A. stutchburyi after 10-day exposure to these metals in the laboratory. Both bivalves accumulated Pb and Zn, while bioaccumulation of Cu only occurred in A. stutchburyi in the presence of Zn. There was some evidence that the presence of Pb could increase bioaccumulation of Zn. Bioaccumulation was generally much higher in M. liliana than in A. stutchburyi, potentially suggesting their higher uptake rates of metals and thus explaining the higher sensitivity of M. liliana to these heavy metals. Bioaccumulation of Pb in the bivalves and its potential influences on the bioavailability of other metals indicated that, despite the lack of any evidence for acute toxicity of Pb in previous studies, it could still pose a potentially important environmental threat. Bioaccumulation of heavy metals found in the present study also highlights the needs for further investigations of potential chronic toxicity of these metals.  相似文献   

16.
The effects of copper (Cu), chromium (Cr), cadmium (Cd), lead (Pb) and zinc (Zn) on the biotransformation of organic acids (acetate, propionate and butyrate) and H2 were assessed in serum-bottle microcosms. Experiments were performed over a range of metal concentrations (20–200 mg/1) using biomass from an anaerobic bioreactor fed continuously with ethanol distillery waste as inoculum. In general, the added metals inhibited the biotransformation of organic acids with increasing metal concentration. However, the extent of inhibition varied for the different biotransformations and for the different metals tested. For example, the concentration of CuCl2 effecting a 50% reduction in the rate constant for biotransformation of acetate, propionate and butyrate was 60, 75 and 30 mg/1, respectively. Cu and Cr (VI) were the most inhibitory metals in organic acid transformation, whereas Pb was the least toxic. The rate of biotransformation of acetate was reduced by half at Cu and Cr concentrations of 60 and 40 gm/1 respectively, whereas Cd, Pb, and Zn concentrations of 160 to 200 mg/l had little effect. The activities of hydrogenotrophic methanogens were much less affected by the same metals and metal concentrations.  相似文献   

17.
  • 1.1. The larvae of mayflies (Baetis thermicus) that inhabited a metal-contaminated river (the river Mazawa in Yamagata, Japan) were collected and the concentrations of several heavy metals in mayflies were compared with those inhabiting a river not contaminated with metals.
  • 2.2. Cadmium, copper and zinc in mayflies of the contaminated river were 13.4, 18.4 and 15.6 times higher in concentration than those in the non-contaminated river.
  • 3.3. Distributions of the three metals in the supernatants of the larvae collected from the contaminated and non-contaminated rivers were determined by HPLC-atomic emission spectrometry with inductively coupled argon plasma.
  • 4.4. Cadmium and copper in the supernatant of the larvae collected from the contaminated river were sequestered by metal-binding components induced for the respective metals, while zinc seemed to be bound loosely to native components.
  相似文献   

18.
Treatment of 3-year-old Scots, white, and Austrian pine seedlings with copper sulfate or lead acetate significantly affected energy homeostasis and oleoresin production in the seedlings but did not induce wilting of the seedlings. Inoculation of copper sulfate-treated or lead acetate-treated white, Scots, and Austrian pine seedlings with the white pine specific pathotype of Bursaphelenchus xylophilus, VPSt-1, caused a significant increase in oleoresin production, stressed energy homeostasis, and induced rapid wilting of the seedlings. Scots pine lost tolerance and Austrian pine lost resistance to VPSt-1 after the seedlings were treated with either copper sulfate or lead acetate. These results suggest that environmental pollution may significantly affect susceptibility of pines to B. xylophilus and may have a role in establishment of this nematode in uninfested areas.  相似文献   

19.
Summary The influence of heavy metal additions on availability and uptake of cadmium, lead, zinc, copper, manganese and iron by oat was studied. The experiments were carried out as pot experiments using sandy loam, sandy soil and organic soil. Selective extractants were used to remove metals held in different soil fractions.Lead and copper were preferently bound by organics and oxides, zinc by oxides and inorganics, and cadmium by inorganics and organics.Addition of cadmium to the soils resulted in higher cadmium concentrations in all plant parts but lower concentrations of lead, zinc, copper, manganese and iron, and the accumulation indexes of these metals were also lower when cadmium was added to the soil.Addition of cadmium plus lead, zinc and copper resulted in higher cadmium concentrations in leaves and straw of plants grown in sandy loam and sandy soil, but lower concentrations when plants were grown in organic soil as compared with the results when cadmium was added separately. The transfer of cadmium, lead, zinc and copper from soil to plant was greatest from sandy soil, and zinc and cadmium were more mobile in the plant than were lead and copper.Cadmium concentrations in leaves correlated significantly with CaCl2 and CH3COOH extractions in sandy loam and sandy soil and with CH3COOH extractions in organic soil.Generally, the total metal uptake was lowest from organic soil.  相似文献   

20.
Concentrations of zinc, cadmium, chromium, nickel, lead, copper and iron were measured in flowing water, riverbed sediments and tissues of sharptooth catfish Clarias gariepinus from three rivers in the upper Manyame catchment over seven months in 2008–2009. The Manyame and Mukuvisi rivers are severely polluted by industrial and domestic effluent, whilst the Gwebi River is not influenced by urban effluent. Key water quality parameters, including dissolved oxygen and conductivity, clearly showed a pollution gradient in the Mukuvisi and Manyame rivers, but water quality in the Gwebi River was good. Levels of zinc, iron, copper, nickel and lead in fish tissues from the three rivers sampled were unusually high, with zinc and iron concentrations being the highest in all the tissues. This was also positively correlated with the concentrations of these metals in water and sediments. Notable differences existed between the water (zinc and copper) and sediments (iron and zinc) of each river. The relatively high metal concentrations in the Gwebi River, as well as conductivity and dissolved ions, were explained by the geological influence of the Great Dyke in its subcatchment. Metals are bound in the sediment but these can be rapidly mobilised into water if environmental changes occur, therefore efforts to monitor and prevent further water quality deterioration are required. The results of this study may have significant negative implications for aquatic organisms and for human health through fish consumption and therefore risk assessment investigations are imperative.  相似文献   

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