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1.
Lead, zinc, and cadmium were determined in a range of tissues from wild populations of bank voles (Clethrionomys glareolus) trapped on an abandoned metalliferous mine site and a reference site. Estimated dietary intakes indicated that animals were exposed to elevated levels of all three metals at the mine site, and this was generally reflected in metal residues in body tissues. Lead concentrations were significantly higher in all tissues of animals from the mine compared to the reference site, while Cd was higher only in the kidney. There was evidence of age-accumulation (using total body weight as an index of age) of Cd in both the liver and kidney of mine site animals but no evidence of such accumulation of lead in bone. In contrast to Cd and Pb, Zn was lower in the tissues of mine site animals compared to the reference site. Based on critical tissue concentrations, the ecotoxicological risk to a wild population of bank voles (Clethrionomys glareolus), associated with total substrate levels of 1 microg g(-1) dry weight Cd and 700 microg g(-1) dry weight Zn at this mine site is negligible, but that associated with 4000 microg g(-1) dry weight Pb may be considered significant.  相似文献   

2.
Twenty-two rabbits were given repeated subcutaneous injection of cadmium chloride. The cumulative cadmium dose given ranged from 13 to 214 mumole/kg body weight. Five rabbits served as controls. The treatment resulted in cadmium concentrations in kidney cortex that ranged from 0.3 to 3.2 mmole Cd/kg and a subsequent production of metallothionein. The molar ratio of cadmium, zinc, and copper in metallothionein fractions from kidneys with different concentrations of cadmium was determined. At low concentrations of cadmium in rabbit kidneys, zinc was the dominating metal bound to metallothionein (70-90%). At high concentrations of cadmium in kidneys, cadmium was the dominating metal in metallothionein. Evidence of kidney toxicity, in the form of beta2-microglobulinuria, was seen when cadmium constituted 85% of the metal ions recovered from metallothionein fractions. The remaining 15% was zinc. This indicates that at most six of the seven metal-binding sites in mammalian metallothionein are occupied by cadmium and that the remaining site is occupied by zinc. Our data provide further support for the hypothesis that chronic cadmium nephrotoxicity develops when there is a lack of metal-binding sites available for cadmium in metallothionein.  相似文献   

3.
Lead, zinc, and cadmium were determined in a range of tissues from wild populations of bank voles (Clethrionomys glareolus) trapped on an abandoned metalliferous mine site and a reference site. Estimated dietary intakes indicated that animals were exposed to elevated levels of all three metals at the mine site, and this was generally reflected in metal residues in body tissues. Lead concentrations were significantly higher in all tissues of animals from the mine compared to the reference site, while Cd was higher only in the kidney. There was evidence of age-accumulation (using total body weight as an index of age) of Cd in both the liver and kidney of mine site animals but no evidence of such accumulation of lead in bone. In contrast to Cd and Pb, Zn was lower in the tissues of mine site animals compared to the reference site. Based on critical tissue concentrations, the ecotoxicological risk to a wild population of bank voles (Clethrionomys glareolus), associated with total substrate levels of 1 μg g−1 dry weight Cd and 700 μg g−1 dry weight Zn at this mine site is negligible, but that associated with 4000 μg g−1 dry weight Pb may be considered significant. Received: 28 January 2002/Accepted: 29 July 2002  相似文献   

4.
Metallothionein, cadmium, zinc, copper, and mercury concentrations were measured in adult lesser black-backed gulls, Larus fuscus; and metallothionein, cadmium, zinc, and copper concentrations were measured in fledgling Cory's shearwaters, Calonectris diomedea. In gulls, metallothionein was positively correlated with cadmium (kidney r=0.83, liver r=0.46), zinc (kidney r=0.46, liver r=0.37), and copper (kidney r=0.28, liver r=0.34). Mercury levels in lesser black-backed gulls showed no correlations with metallothionein or with any other metal. In shearwaters metallothionein was positively correlated with cadmium in the kidney (r=0.41) but not in liver, zinc in kidney (r=0.43) and liver (r=0.52), and copper in kidney (r=0.55) but not in liver. Cadmium levels were the most important factor determining tissue metallothionein concentrations in adult lesser black-backed gulls demonstrating the role of metallothionein in heavy metal detoxification. In fledgling Cory's shearwaters, the most important factor in determining metallothionein concentrations in kidney was copper concentrations, and in liver, zinc concentrations. During the latter phases of chick growth high levels of zinc are required for feather development, and at this time the binding of cadmium may be masked by the presence of a large amount of zinc- and copper-bound metallothionein. These results illustrate disparate roles of metallothionein, the levels of which will be in a state of flux both seasonally and annually.  相似文献   

5.
Cadmium, zinc, and copper were determined in liver and in kidney cortex samples obtained from 33 normal Swedish horses. Cadmium concentrations in liver ranged from 0.002 to 0.165 mmole/kg and in kidney from 0.01 to 2.15 mmole/kg. There was a significant correlation between liver and kidney concentrations of cadmium. The average kidney concentration of cadmium was about 15 times that of liver. Zinc concentrations increased with increasing cadmium concentrations in both liver and kidney. The relative increase of zinc with cadmium was more pronounced in liver than in kidney. However, the absolute increase of zinc was larger in kidney due to the much higher concentration of cadmium in kidney compared to liver. Any significant correlation between copper and cadmium, or copper and zinc, could not be revealed. Sephadex gel filtration was performed on supernatants from homogenates of kidney and liver from 19 of the horses. In both organs the major part of cadmium was recovered in protein fractions corresponding to metallothionein (MT), in which the increase of zinc also took place. The molar ratio between zinc and cadmium was higher in MT fractions obtained from liver than in MT fractions obtained from kidney.  相似文献   

6.
This study investigated metals of tailings from Tonglvshan mine in Daye and assessed the effect of metal contamination in water and sediment near the tailing reservoir. The concentration of copper, lead, zinc, cadmium, chromium and nickel was measured in deposit samples taken from a profile in an abandoned flotation tailing reservoir, as well as in water and sediment samples near the reservoir. The results of this study indicate that copper concentration ranges from 780 to 4390 mg/kg, 2–10 times higher than the limit values in soil, while the contents of other metals are below the limit values. Metal levels in water and sediments are high and varied widely in different sampling sites. The mean concentrations of copper, lead, zinc, cadmium, chromium and nickel in waters are 27.76, 2.28, 8.20, 0.12, 5.30 and 3.04 mg/L, while those in sediments are 557.65, 96.95, 285.20, 0.92, 94.30 and 4.75 mg/kg, respectively. All of the results indicate that the environment near the tailing reservoir is polluted to some extent by some kinds of metals, especially by copper, lead, zinc and cadmium, which may be caused not only by some discharge sources of metals, but also by life garbage and sewage.  相似文献   

7.
The vicinity of an ancient abandoned copper mine located on the Isle of Anglesey was assessed for the dispersion of copper, zinc, lead, and cadmium into the surrounding environment. Extraction of soil, lichens, cattle feces, and Calluna vulgaris L. (ling) tissue, using aqua regia, was carried out and together with water samples, these were analyzed using flame atomic absorption spectroscopy. Atmospheric dispersion and dilution was plotted from the workings to the coast and the resultant dilution ascertained. Evidence of bioaccumulation by plants and animals is presented and partitioning within plants highlighted. The results suggest that atmospheric dispersion has ceased but residual metal concentrations in the soil remain persistent and could present health hazards to animals and humans in the past and in the future.  相似文献   

8.
The present study evaluated whether blood could be used as a nondestructive tool for monitoring metal exposure and related hematological effects in wood mice (Apodemus sylvaticus L.) living along a metal pollution gradient. Soil concentrations of arsenic, cadmium, copper, lead, silver, and zinc decreased with distance from the emission source. Blood levels of cadmium and lead differed significantly among sites, whereas those of the other metals did not. Blood levels of cadmium and lead correlated with soil concentrations of cadmium and lead, respectively. No such significant relationships were found for the other measured metals. Hematocrit levels decreased in wood mice from the most polluted site (45.96% +/- 0.53% [mean +/- standard error]) compared to the reference site (48.04% +/- 0.47%). A negative correlation between hematocrit and blood levels of cadmium and lead was found. Erythrocyte count, leukocyte count, hemoglobin concentration, mean corpuscular hemoglobin (average wt of hemoglobin in a red blood cell in pg), and lysozyme activity did not differ among study sites. Mean corpuscular volume (average volume of a red blood cell in microm3) and mean corpuscular hemoglobin concentration (average proportion of hemoglobin in a red blood cell as a %) differed among study sites but showed no relationship with metal exposure. We conclude that whole blood from mice can be used for nondestructive monitoring of the exposure to nonessential metals under natural conditions. The present results indicate that decreased hematocrit levels may be an early warning signal for a negative impact of metal exposure on the oxygen-transport capacity of blood in wood mice in their natural environment.  相似文献   

9.
Cadium, zinc, and copper were determined in kidney cortex samples and in protein fractions obtained from 20 normal Swedish horses. Cadmium concentrations in kidneys ranged from 0.01 to 1.46 mmole/kg. Zinc concentrations in kidneys increased with increasing cadmium concentrations. At low concentrations of cadmium the increase of zinc was almost equimolar with the increase in cadmium, but at higher concentrations of cadmium the increase of zinc was less pronounced. Copper concentrations ranged from 0.07 to 0.22 mmole Cu/kg and were not related to the cadmium concentration. The increase of zinc in kidney cortex took place in the metallothionein (MT) fractions, where also almost all cadmium was recovered. The molar ratio of zinc and cadmium in MT was close to one at low concentrations (below 0.1 mmole/kg) of cadmium but the ratio decreased with increasing cadmium concentrations in the kidney. This change in molar ratio of zinc and cadmium in MT explains the leveling off in zinc increase at cadmium concentrations in kidney exceeding 0.6 mmole/kg.  相似文献   

10.
Determination of soil concentrations of trace and pollutant metals over large spatial areas requires laborious and expensive sampling effort. In this study, we examined the feasibility of using calves as biomonitors of soil semimetal and trace metal concentrations in Galicia (NW Spain), a region in which calves are predominantly reared on grass or locally grown forage. We determined the concentrations of arsenic, copper, and zinc in the liver, kidney, muscle, and blood of calves from across Galicia and related them to the metal concentrations in the soil from the areas in which the animals were reared. For each element, liver (but not usually kidney, muscle, or blood) concentrations were significantly elevated in animals from areas with higher soil concentrations. Liver arsenic concentrations were only markedly greater in animals from areas with soil arsenic levels > 20 mg/kg, and calves may not be sensitive enough biomonitors of background variation in soil levels, although they may be useful for monitoring anthropogenic arsenic contamination. Copper and zinc liver levels increased progressively with soil levels, and the pattern was especially marked for copper. The relatively unusual copper metabolism of cattle and other ruminants may make them particularly good biomonitors for environmental concentrations of this metal. Received: 13 August 2001/Accepted: 23 January 2002  相似文献   

11.
We studied the bioavailability and toxicity of copper, zinc, arsenic, cadmium, and lead in sediments from Lake Roosevelt (LR), a reservoir on the Columbia River in Washington, USA that receives inputs of metals from an upstream smelter facility. We characterized chronic sediment toxicity, metal bioaccumulation, and metal concentrations in sediment and pore water from eight study sites: one site upstream in the Columbia River, six sites in the reservoir, and a reference site in an uncontaminated tributary. Total recoverable metal concentrations in LR sediments generally decreased from upstream to downstream in the study area, but sediments from two sites in the reservoir had metal concentrations much lower than adjacent reservoir sites and similar to the reference site, apparently due to erosion of uncontaminated bank soils. Concentrations of acid-volatile sulfide in LR sediments were too low to provide strong controls on metal bioavailability, and selective sediment extractions indicated that metals in most LR sediments were primarily associated with iron and manganese oxides. Oligochaetes (Lumbriculus variegatus) accumulated greatest concentrations of copper from the river sediment, and greatest concentrations of arsenic, cadmium, and lead from reservoir sediments. Chronic toxic effects on amphipods (Hyalella azteca; reduced survival) and midge larvae (Chironomus dilutus; reduced growth) in whole-sediment exposures were generally consistent with predictions of metal toxicity based on empirical and equilibrium partitioning-based sediment quality guidelines. Elevated metal concentrations in pore waters of some LR sediments suggested that metals released from iron and manganese oxides under anoxic conditions contributed to metal bioaccumulation and toxicity. Results of both chemical and biological assays indicate that metals in sediments from both riverine and reservoir habitats of Lake Roosevelt are available to benthic invertebrates. These findings will be used as part of an ongoing ecological risk assessment to determine remedial actions for contaminated sediments in Lake Roosevelt.  相似文献   

12.
The objectives of this study were to evaluate the use of practical supplemental dietary zinc to modify the cadmium content in edible bovine tissues and to identify copper interactions with cadmium and zinc. The effect of supplemental zinc (200 or 600 μg/g) on the concentrations of cadmium, zinc, and copper in liver, kidney cortex, muscle, and blood of calves fed 50 μg/g cadmium for 60 days was evaluated. Blood samples were collected before and eight times after starting to feed cadmium or cadmium plus zinc. Liver, kidney, and muscle samples were collected when calves were slaughtered (baseline, at beginning of experimental feeding; cadmium-fed, at end of 60 days feeding). The cadmium concentrations of all sample types collected were markedly increased by the feeding of cadmium. Feeding 600 μg/g supplemental zinc significantly increased the zinc concentrations of liver, kidney cortex, and blood and decreased the cadmium accumulation in these organs as well as muscle. The copper concentrations of muscle or blood were not altered by feeding cadmium with or without zinc but those of liver and kidney cortex were significantly increased by higher dietary levels of zinc and cadmium. The potential use of dietary zinc salts in reducing cadmium body burden in food animals suspected or known to have high cadmium intakes is suggested.  相似文献   

13.
During August–November 1992 and August 1993, bed sediment and fish liver were sampled in the South Platte River Basin and analyzed for 45 elements in bed sediment and 19 elements in fish liver. The results for aluminum, arsenic, cadmium, chromium, copper, iron, lead, manganese, selenium, silver, uranium, and zinc are presented here. All 12 trace elements were detected in bed sediment, but not all were detected in fish liver or in all species of fish. A background concentration of trace elements in bed sediment was calculated using the cumulative frequency curves of trace element concentrations at all sites. Arsenic, cadmium, copper, lead, manganese, silver, uranium, and zinc concentrations were greater than background concentrations at sites in mining areas or at sites that have natural sources of these elements. Trace element concentrations in fish liver generally did not follow the same patterns as concentrations in bed sediment, although concentrations of aluminum and cadmium were higher in fish liver collected at mountain sites that had been disturbed by mining. Concentrations of aluminum, arsenic, cadmium, chromium, copper, iron, lead, silver, and zinc increased in bed sediments in urban areas. Iron, silver, and zinc concentrations in fish liver also increased in urban areas. Concentrations of cadmium, copper, silver, and zinc in fish liver increased in the agricultural areas of the basin. Downstream changes in trace element concentrations may be the result of geological changes in addition to changes in land use along the river. Received: 5 April 1996/Revised: 27 July 1996  相似文献   

14.
This study measured concentrations of iron, manganese, zinc, copper, lead, and cadmium in environmental substrates (water and sediment) as well as in the diet and feathers of Black-crowned Night Heron Nycticorax nycticorax and Grey Heron Ardea cinerea chicks from Pyeongtaek heronry, Gyeonggi-do, Korea. Zinc and cadmium concentrations in sediment were relatively high, but lead was low. In the diet, only copper concentrations were higher in Black-crowned Night Herons than in Grey Herons. Cadmium concentrations in the diet of two heron species from a Pyeongtaek heron colony were also higher than reported in other studies. In feathers, iron, copper, and lead concentrations were significantly different between heron species. Iron and copper concentrations were higher in Black-crowned Night Heron chicks than in Grey Heron chicks, but lead concentrations were not. Therefore, with the exception of lead, heavy metal concentrations in feathers were not related to concentrations in the diet. Zinc, iron, and lead concentrations in heron feathers were within the ranges reported by other heron studies, but manganese, copper, and cadmium were much higher. Lead and cadmium concentrations in feathers of Black-crowned Night Heron and Grey Heron chicks were elevated to lead and cadmium concentrations in the diet. Therefore, we suggest that lead and cadmium concentrations in heron feathers reflect contamination of breeding sites and are useful bioindicators of local contamination. An erratum to this article is available at .  相似文献   

15.
The potential effects of proposed lead-zinc mining in an ecologically sensitive area were assessed by studying a nearby mining district that has been exploited for about 30 yr under contemporary environmental regulations and with modern technology. Blood and liver samples representing fish of three species (largescale stoneroller, Campostoma oligolepis, n=91; longear sunfish, Lepomis megalotis, n=105; and northern hog sucker, Hypentelium nigricans, n=20) were collected from 16 sites representing a range of conditions relative to lead-zinc mining and ore beneficiation in southeastern Missouri. Samples were analyzed for lead, zinc, and cadmium, and for a suite of biomarkers (reported in a companion paper). A subset of the hog sucker (n=9) representing three sites were also analyzed for nickel and cobalt. Blood and liver lead concentrations were highly correlated (r=0.84-0.85, P<0.01) in all three species and were significantly (ANOVA, P<0.01) greater at sites <10 km downstream of active lead-zinc mines and mills and in a historical lead-zinc mining area than at reference sites, including a site in the area proposed for new mining. Correlations between blood and liver cadmium concentrations were less evident than for lead but were nevertheless statistically significant (r=0.26-0.69, P <0.01-0.07). Although blood and liver cadmium concentrations were highest in all three species at sites near mines, within-site variability was greater and mining-related trends were less evident than for lead. Blood and liver zinc concentrations were significantly correlated only in stoneroller (r=0.46, P<0.01) and mining-related trends were not evident. Concentrations of cobalt and nickel in blood and liver were significantly higher (ANOVA, P<0.01) at a site near an active mine than at a reference site and a site in the historical lead-zinc mining area. These findings confirm previous studies indicating that lead and other metals are released to streams from active lead-zinc mines and are available for uptake by aquatic organisms.  相似文献   

16.
From 1997 until 1999 the extent and the ecological effects of zinc, copper, lead, and cadmium pollution were studied in different reaches of the South American Pilcomayo River. A comparison of metal concentrations in water, sediment, and chironomid larvae, as well as the diversity of macroinvertebrate species, was made between sites near the origin of the Pilcomayo River, with hardly any mining activities, sites in the Potosí region, with intensive mining, and sites located 500 km or further downstream of Potosí, in the Chaco plain. Samples were also collected in an unpolluted river (Cachi Mayu River) and in the Tarapaya River, which is strongly contaminated by mine tailings (1000 tons a day). The upper parts of the Pilcomayo River are strongly affected by the release of mine tailings from the Potosí mines where mean concentrations of lead, cadmium, copper, and zinc in water, filtered water, sediment, and chironomid larvae were up to a thousand times higher than the local background levels. The diversity of the benthic macroinvertebrate community was strongly reduced in the contaminated parts; 97% of the benthic macroinvertebrates consisted of chironomid larvae. The degree of contamination in the lower reaches of the river, however, was fairly low because of sedimentation processes and the strong dilution of mine tailings with enormous amounts of clean sediment from erosion processes. Analysis of sediment cores from the Ibibobo floodplain, however, reveal an increase of the heavy metal concentrations in the lower reaches since the introduction of the contaminating flotation process in the mine industry in 1985. Received: 7 March 2002/Accepted: 19 August 2002  相似文献   

17.
The concentrations of Zn, Cu, Pb, and Cd in the liver, kidneys, spleen, bones, and carcass of laboratory mice BALB/cy were observed in toxicological experiments. Polymetal industrial dust containing these metals was given to experimental animals at 1% concentration mixed with conventional animal food. Samples for analyses were taken on Days 15, 40, 60, 90, and 120 posttreatment. The experimental data clearly support the established antagonistic interactions among cadmium, zinc, copper, and lead. A mathematical model was proposed to study the main tendencies of heavy metal bioaccumulation under conditions of metal interaction and excessive exposure. The experimental results were assessed on the basis of the model. A rate constant of renal excretion greater than that of hepatic excretion was obtained, which agrees with the observed inversion of cadmium kidney/liver ratio in the conditions of very high exposure.  相似文献   

18.
Children living near hazardous waste sites may be exposed to environmental contaminants, yet few studies have conducted multi-media exposure assessments, including residential environments where children spend most of their time. We sampled yard soil, house dust, and particulate matter with aerodynamic diameter <2.5 in 59 homes of young children near an abandoned mining area and analyzed samples for lead (Pb), zinc (Zn), cadmium (Cd), arsenic (As), and manganese (Mn). In over half of the homes, dust concentrations of Pb, Zn, Cd, and As were higher than those in soil. Proximity to mine waste (chat) piles and the presence of chat in the driveway significantly predicted dust metals levels. Homes with both chat sources had Pb, Zn, Cd, and As dust levels two to three times higher than homes with no known chat sources after controlling for other sources. In contrast, Mn concentrations in dust were consistently lower than in soil and were not associated with chat sources. Mn dust concentrations were predicted by soil concentrations and occupant density. These findings suggest that nearby outdoor sources of metal contaminants from mine waste may migrate indoors. Populations farther away from the mining site may also be exposed if secondary uses of chat are in close proximity to the home.  相似文献   

19.
Studies on the impacts of pollutant metals and metalloids on livestock have largely focused on animals with relatively high levels of exposure. The impact of low-level environmental contamination, which is more common on agricultural land, is largely unknown. The principal aim of the present study was to examine the effects of low-level environmental contamination on trace metal metabolism in cattle from the rural and relatively uncontaminated region of Galicia (NW Spain). Correlations between toxic (cadmium, lead, and arsenic) and essential trace elements (copper and zinc) were evaluated in the tissues (liver, kidney, and muscle) and blood of 494 cattle from throughout Galicia. Cadmium was the toxic element that had the greatest influence on copper and zinc homeostasis. There was a significant positive association between renal cadmium and zinc residues and a significant negative correlation between kidney cadmium and copper. These interactions are likely to be the result of cadmium-induced effects on metallothionein synthesis. Lead and zinc were positively associated in the kidney, although the mechanism of this interaction is uncertain. Arsenic and copper concentrations were strongly correlated with each other in the liver and may indicate that the high copper levels in animals from copper-rich areas in Galicia interfere with their arsenic excretion. The essential metals copper and zinc were also significantly associated with each other in calves but not in cows. Received: 24 April 2001/Accepted: 10 September 2001  相似文献   

20.
The objective of this study was to quantify the relationships between heavy metal concentrations in soil, leaf litter, and ground beetles at four sampling sites of a forest ecosystem in Medvednica Nature Park, Croatia. Ground beetles were sampled by pitfall trapping. Specimens were dry-ashed and soil and beetle samples digested with nitric acid. Lead, cadmium, copper, zinc, manganese, and iron were analyzed using atomic absorption spectrometry. Statistically significant differences between plots were found for lead, cadmium, and iron in ground beetles. Correlations between ground beetles and soil or leaf litter were positive for lead and cadmium concentrations and negative for iron concentration. Differences in species metal concentrations were recorded. Higher concentrations of all studied metals were found in female beetles. However, a significant difference between sexes was found only for manganese. Significant differences in species metal concentrations were found for species that differ in feeding strategies and age based on breeding season and emergence of young adults.  相似文献   

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