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1.
Levels of nine heavy metals were measured in the livers and salt glands of greater scaup (Aythya marila), black duck (Anas rubripes) and mallard (A. platyrhynchos) from Raritan Bay, New Jersey to determine if the functioning avian salt gland concentrates heavy metals. Heavy metals examined were cadmium, cobalt, chromium, copper, lead, mercury, manganese, nickel and zinc. Heavy metal levels varied significantly by species and tissue for chromium, copper, lead, and manganese, and by tissue for cobalt, mercury, nickel and zinc. In comparing tissues cobalt was higher in the salt glands than in livers of all three species; chromium and nickel were higher in the salt gland than liver for mallard and black duck; and lead, manganese and zinc were higher in the liver than the salt gland in greater scaup. Generally metal levels were higher in the salt gland for mallard and black duck, and in the liver for greater scaup.  相似文献   

2.
Metal tolerance in tissue cultures of anthoxanthum odoratum   总被引:1,自引:0,他引:1  
Tissue cultures were initiated from one non-tolerant (S20) and two zinc and lead tolerant (T92 and T94) clones of Anthoxanthum odoratum. Growth of callus from the non-tolerant clone was reduced by the presence of zinc, lead, copper and nickel, whereas callus from the two tolerant clones showed no reduction of growth in the presence of zinc and lead but growth was reduced by copper and nickel. The specificity of metal tolerance shown by the parental material was maintained in the callus. Tolerant and non-tolerant callus accumulated similar amounts of zinc and lead.  相似文献   

3.
D. Purves 《Plant and Soil》1967,26(2):380-382
Summary Spectrochemical analysis of representative samples of topsoil from urban gardens and from individual fields in rural areas indicates that the levels of total copper, EDTA-extractable copper, water-soluble boron, and acetic-acid extractable lead are markedly enhanced in urban areas. No significant differences were discovered between levels of these elements in soils from built-up areas in small towns and large conurbations. These results suggest the possibility of general enhancement of the trace element content of plants grown in private gardens in built-up areas.  相似文献   

4.
The sorption uptake of cadmium, nickel, zinc, copper and lead by marine brown alga Fucus spiralis was investigated in bimetallic, trimetallic and multimetallic solutions. The experimental data fitted very well to Langmuir model. In bimetallic systems, the affinity of biomass for lead and copper increased and the sorption uptake of these metals was not affected by increasing concentrations of cadmium, nickel or zinc. However, in solutions with both metals there was a significant mutual decrease of their sorption levels at high concentrations of the other metal. The sorption uptake of cadmium, nickel and copper was investigated in trimetallic aqueous systems. Based on the kinetic parameter b, the affinity of F. spiralis for copper was considerably higher than for cadmium or nickel: bCd=6.39, bNi=1.82 and bCu=17.89. In all tests, the maximum sorption uptake remained practically constant around 1 mmol/g, indicating that the number of active sites on the biomass was limited. Tests with four and five metals showed that copper was preferentially adsorbed. The differences between the experimental sorption data and those given by the chemical speciation program PHREEQCI were negligible. In general, the software used provided satisfactory estimated data for each metal and hence can be a useful tool to predict or simulate the real process.  相似文献   

5.
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   

6.
Plasmid-determined resistances to compounds of such toxic elements as antimony, arsenic, bismuth, boron, cadmium, chromium, copper, mercury, lead, nickel, silver, tellurium and zinc occur at high frequencies in natural populations of common bacteria. Considerable study has been made of the resistances to cadmium and to arsenic which result from altered transport and of resistance to mercury which results from biotransformation. However, much remains to be learned about all of these resistances which have potential for use in engineering microbes for applications in biotechnology.  相似文献   

7.
Changes in the composition of the soil mycoflora after soil treatment with 500, 2000 and 5000 ppm of mercury, zinc, lead, copper, nickel and cadmium, were determined on Czapek's glucose agar at intervals up to 15 weeks. Treatment of soil with mercuric chloride and lead nitrate significantly reduced the fungal population counts for soil treated with zinc or copper sulphate, and with nickel or cadmium chloride counts were increased on some treatments and reduced on others. When heavy metals were incorporated into the isolation medium, they depressed the total count of fungi, as well as affecting individual species.  相似文献   

8.
One of the problematic issues in soil pollution studies is heavy metal particles which are produced by mines and smelting units and spread through wind action and/or runoff. Pollution and health risk assessment of cadmium, lead, zinc, copper, and nickel in soil around the lead and zinc smelting factory was carried out in Zanjan City, Iran. Contamination factor (Cf), pollution load index (PLI), geoaccumulation index (Igeo), hazard quotient (HQ), hazard index (HI), and carcinogenic risk were pollution and human health risk assessment metrics in this study. Based on the Iranian soil guideline value, soil samples in the studied areas were contaminated the least by copper and nickel and the most by cadmium. PLI results showed that soils near the production line were heavily or extremely heavily polluted. The results of Cf and Igeo showed that lead and zinc were the most important contaminants. Health risk assessment indicated that lead and cadmium in soil were the main contaminants, which pose both carcinogenic and non-carcinogenic risks to human health; carcinogenic risk levels were unacceptably high (above 1 × 10?4). It can be concluded that mining and smelting activities degrade soil quality in this region and the soil pollution might be extended to farming areas.  相似文献   

9.
The contents of copper, zinc, lead nickel and cadmium for 322 samples of 44 species growing on copper mine area of Hongtou Shoo were determined. The results showed that the average contents of zinc, nickel, lead, cadmium in dry matter are 51.313 ppm, 1.536 ppm, 0.361 ppm and 0.058 ppm respectively. The variable range of zinc and cad- mium contents is larger, difference between minimum and maximum value is about 30–40 times. Zinc, lead and nickel contents in leaves of xylophyta in dry matter are mostly higher than in branches, but cadmium content of branches in dry matter is higher than leaves. The contents of lead and zinc in plants of minerelization areas are higher than that in non-minerelization areas. The results of correlative analysis showed that the linear regression between the metal contents in plants and soils are significant, for example, Lespedeza bicolor Thalictrum thumbergii, Arundinella hirta et al. It is important in phytogeochemical methods of prospecting for mineral. However, the correlative coefficients between the elements contents in leaves and branches of Quercus liaotungensis and in soils are not obvious. The correlative coefficient of nickel in plants and zinc, lead, cadmium and organic matter contents in soils are mostly negative value, without significant correlation. The results of the principal component analysis showed that the correlation of cadmium and zinc is significant among five elements in the plants. The contributive rate of first principal component is 33.94%, the positive target of the main target constitute is cadmium and zinc.  相似文献   

10.
This study was designed to determine the protective effects of zinc on the hepatotoxicity induced by nickel in rats. Female Sprague-Dawley (SD) rats received either nickel sulfate alone in the dose of 800 mg/L nickel in drinking water, zinc sulfate alone in the dose of 227 mg/L zinc in drinking water, and nickel plus zinc or drinking water alone for a total duration of 8 wk. The effects of different treatments were studied on activities of rat liver marker enzymes like alkaline phosphatase (ALP), alanine aminotransferase (ALT), and aspartate aminotransferases (AST) and on the status of essential elements in rat liver. The study revealed a significant increase in the activities of enzymes ALP and ALT in rats subjected to nickel treatment. Interestingly, zinc supplementation to rats treated with nickel brought back the raised activities of these enzymes to within normal limits. Further, the levels of elements in liver that include zinc, copper, selenium, and potassium were found to be significantly suppressed following nickel treatment, whereas the levels of iron and sulfur were elevated. However, zinc treatment alone did not cause any appreciable change in the concentration of these elements. To the contrary, when zinc was given to nickel-treated rats, the concentrations of zinc, copper, potassium, and phosphorus were not significantly different from that of normal controls, whereas the levels of iron, selenium, and sulfur were improved in comparison to nickel-treated rats but were not within the normal limits. The present study concludes that zinc has the ability to maintain the levels of hepatic elements and has bearing in regulating the liver functions by maintaining the activities of marker enzymes in conditions of nickel toxicity.  相似文献   

11.
J. G. Shiber 《Hydrobiologia》1981,83(3):465-476
Samples of the edible tissue of cephalopod molluscs (cuttlefish, squid, octopus) and crustaceans (lobster, shrimp) collected off the coast of Lebanon were found to concentrate similar levels of cadmium, copper, nickel, and chromium. Lead and zinc were highest in the cephalopods and iron was highest in the crustaceans.The molluscs collected from Beirut had higher levels of many metals than those taken from the other locations. The Beirut octopus had higher lead, cadmium, copper, iron, and chromium. Lead, cadmium, and copper were also highest in the Beirut cuttlefish while iron and zinc were elevated. The crustaceans from Beirut showed no strong tendency to concentrate higher metal levels, except for the Beirut lobster which had higher copper than the other samples.In the cuttlefish, the analysis of bone showed generally higher cadmium, zinc, nickel, and chromium but lower copper and iron than the muscle. However, at Beirut, the bone samples had much higher iron. Levels of most metals in the exoskeletons of the lobster and shrimp were quite similar to those in the muscle tissue with the exception of iron in the lobster which was highest in the exoskeleton, and zinc in both crustaceans, which was more highly concentrated in the muscle.  相似文献   

12.
This study compares the seminal plasma trace metal levels of hospital workers with groups of industrial workers in a petroleum refinery, smelter, and chemical plant. The metals measured were the essential metals (copper, zinc, nickel, cobalt, and manganese) and the toxic metals (lead, cadmium, and aluminum). The group mean±SE metal level for each group (50 subjects per group) was calculated, and the statistical significance of the group mean differences of the industrial groups with the hospital group (control) was determined by the Student’s t-test. The differences observed in the smelter group were increased copper and zinc (p≤0.001) and decreased nickel, cobalt, and manganese (p≤0.001,≤0.01). The refinery group differences were increased copper, zinc, and nickel (p≤0.001) but decreased cobalt and manganese (p≤0.001). The chemical group differences were increased zinc (p≤0.001) and decreased cobalt (p≤0.001). The seminal plasma levels of the toxic metals lead and aluminum were increased in each of the industrial groups (p≤0.001). Concurrent differences were (1) decreased accumulation of nickel, cobalt, and manganese in the smelter group, (2) decreased cobalt and managanese in the refinery group, and (3) only decreased cobalt in the chemical group.  相似文献   

13.
Survey of metal tolerance in moderately halophilic eubacteria.   总被引:6,自引:3,他引:3       下载免费PDF全文
The tolerance patterns, expressed as MICs, for 250 moderately halophilic eubacteria to 10 heavy metals were surveyed by using an agar dilution method. The moderate halophiles tested included 12 culture collection strains and fresh isolates representative of Deleya halophila (37 strains), Acinetobacter sp. (24 strains), Flavobacterium sp. (28 strains), and 149 moderately halophilic gram-positive cocci included in the genera Marinococcus, Sporosarcina, Micrococcus, and Staphylococcus. On the basis of the MICs, the collection strains showed, overall, similar responses to silver, cobalt, mercury, nickel, lead, and zinc. All were sensitive to silver, mercury, and zinc and tolerant of lead. The response to arsenate, cadmium, chromium, and copper was very heterogeneous. The metal susceptibility levels of the 238 freshly isolated strains were, in general, very heterogeneous among the four taxonomic groups as well as within the strains included in each group. The highest toxicities were found with mercury, silver, and zinc, while arsenate showed the lowest activity. All these strains were tolerant of nickel, lead, and chromium and sensitive to silver and mercury. Acinetobacter sp. strains were the most heavy-metal tolerant, with the majority of them showing tolerance of eight different metal ions. In contrast, Flavobacterium sp. strains were the most metal sensitive. The influence of salinity and yeast extract concentrations of the culture medium on the toxicity of the heavy metals tested for some representative strains was also studied. Lowering the salinity, in general, led to enhanced sensitivity to cadmium and, in some cases, to cobalt and copper. However, increasing the salinity resulted in only a slight decrease in the cadmium, copper, and nickel toxicities.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

14.
Survey of metal tolerance in moderately halophilic eubacteria   总被引:1,自引:0,他引:1  
The tolerance patterns, expressed as MICs, for 250 moderately halophilic eubacteria to 10 heavy metals were surveyed by using an agar dilution method. The moderate halophiles tested included 12 culture collection strains and fresh isolates representative of Deleya halophila (37 strains), Acinetobacter sp. (24 strains), Flavobacterium sp. (28 strains), and 149 moderately halophilic gram-positive cocci included in the genera Marinococcus, Sporosarcina, Micrococcus, and Staphylococcus. On the basis of the MICs, the collection strains showed, overall, similar responses to silver, cobalt, mercury, nickel, lead, and zinc. All were sensitive to silver, mercury, and zinc and tolerant of lead. The response to arsenate, cadmium, chromium, and copper was very heterogeneous. The metal susceptibility levels of the 238 freshly isolated strains were, in general, very heterogeneous among the four taxonomic groups as well as within the strains included in each group. The highest toxicities were found with mercury, silver, and zinc, while arsenate showed the lowest activity. All these strains were tolerant of nickel, lead, and chromium and sensitive to silver and mercury. Acinetobacter sp. strains were the most heavy-metal tolerant, with the majority of them showing tolerance of eight different metal ions. In contrast, Flavobacterium sp. strains were the most metal sensitive. The influence of salinity and yeast extract concentrations of the culture medium on the toxicity of the heavy metals tested for some representative strains was also studied. Lowering the salinity, in general, led to enhanced sensitivity to cadmium and, in some cases, to cobalt and copper. However, increasing the salinity resulted in only a slight decrease in the cadmium, copper, and nickel toxicities.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

15.
We examined the differences between the concentrations of chemical elements in caries-changed primary teeth and permanent ones with a division into the root and the crown. The study comprised 27 children aged from 4 to 11 yr and 36 adults aged from 36 to 71 yr. We examined the elements with the total reflection X-ray fluorescence method. The lowest concentrations of calcium, manganese, strontium, lead, and copper were in the roots of primary teeth compared to the roots of permanent ones. The calcium, nickel, zinc, lead, and copper concentrations were significantly higher in the roots of primary teeth than in the roots of permanent teeth. However, the zinc concentration was higher both in the root and crown of primary teeth than in permanent teeth. On the basis of our investigations, we can conclude that the content of some elements (manganese, copper, strontium, and lead) is higher in caries permanent teeth than in primary ones. The nickel and zinc concentrations are higher in the teeth of the children than the adults. However, the content of other elements (calcium, chromium, iron) is similar in both kinds of teeth.  相似文献   

16.
The present study aims to examine the effects of both physical activity and vitamin A supplementation on trace element metabolism in individuals engaged in taekwondo. The study registered seven healthy male national taekwondo players whose mean age was 21.86 ± 0.34 years and mean weight was 64.86 ± 2.72 kg. The subjects were supplemented with oral administration of 100 mg vitamin A (retinol) for 6 weeks, and concurrently, they were subjected to taekwondo training 5 days a week. Before starting the vitamin A supplementation, blood samples were taken from the subjects twice, once at rest and once after exhaustion. Similarly, at the end of the 6-week vitamin A supplementation, two blood samples were taken from the subjects, once at rest and once after exhaustion, in order to determine (by atomic emission) and compare serum cobalt, molybdenum, calcium, cadmium, chromium, copper, manganese, sodium, nickel, phosphorus, sulfur, iron, boron, and zinc (mg/L) levels. Values of boron and nickel dropped significantly after 6-week vitamin A supplementation (p < 0.001). Reduced levels of boron and nickel we obtained in the present study are believed to result from the antioxidant effect of long-term vitamin A supplementation.  相似文献   

17.
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   

18.
Pollutants deposited on the Severn Estuary from the atmosphere derive mainly from local industrial and urban centres. Atmospheric deposition accounts for 50% of the lead and zinc inputs, 10–20% of the cadmium, copper and nickel to the Estuary, but only a small proportion of the chromium, iron and manganese. Most of the cadmium, copper and lead comes from the lower atmosphere near Avonmouth and Cardiff Bay. Westerly winds have much higher sodium and chloride concentrations but generally carry lower pollution loads than the less frequent, offshore easterlies. Strong winds recycle pollutants into the atmosphere via sea spray. The hills on both sides of the Estuary encourage deep vertical mixing, and effluents may be carried well inland. Stable atmospheres, associated with southerly and easterly airflows, cause trapping and entrainment of stack emissions. Thus easterlies may deposit much higher levels of pollutants. This paper reviews present knowledge regarding the deposition of metals from the atmosphere into the waters of the Severn Estuary. Preliminary results (1989) indicate that, while distribution patterns remain broadly similar, the quantities deposited were considerably less than they were six years previously.  相似文献   

19.
Inductively coupled plasma atomic emission spectrometry (ICP-AES) was used to study element ions in whole bodies of uninfected Biomphalaria glabrata snails and those experimentally infected with larval Schistosoma mansoni trematodes. Infected snails were analysed 8 weeks post-infection. Cohort snails that were left uninfected were analysed at the same time as the infected snails. Sixteen elements (aluminum, boron, barium, calcium, cadmium, copper, iron, potassium, magnesium, manganese, sodium, nickel, lead, selenium, tin and zinc) were found to be present in infected and uninfected whole bodies at concentrations above the detection limit of the ICP-AES analysis. Of these, calcium, cadmium, manganese and sodium were present in significantly higher amounts (Student's t-test, P<0.05) in whole infected versus whole uninfected snails. Variations in the present results compared with other studies reflect intrinsic differences in the larval trematode-snail systems used.  相似文献   

20.
Influence of chosen elements on the dynamics of the cariogenic process   总被引:1,自引:0,他引:1  
This prospective study comprised 140 natural crowns of the teeth extracted from 31 boys and 35 men, as well as 39 girls and 35 women. They were divided into two groups. Group I consisted of primary teeth and group II consisted of permanent teeth. In each group, two subgroups were distinguished: subgroup A containing teeth without caries and subgroup B comprising carietic teeth. Zinc, iron, copper, nickel, chromium, cobalt, lead, cadmium, selenium, and strontium were determined in the samples by using the total reflection X-ray fluorescence method. Significantly higher concentrations of zinc, iron, copper, nickel, selenium, and strontium were detected in the crowns of healthy primary and permanent teeth than in the crowns of the carietic primary and permanent teeth. The concentrations of chromium, cobalt, lead, and cadmium were significantly higher in primary and permanent teeth with caries than in the healthy ones. Judging from the obtained results, we think that lower concentrations of zinc, iron, copper, nickel, selenium, and strontium together with higher concentrations of chromium, cobalt, lead, and cadmium in the carietic primary and permanent teeth, in relation with the respective concentrations of those elements in healthy teeth, can be one of the caries risk factors.  相似文献   

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