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1.
Cadmium, copper, lead, nickel and zinc concentrations were analysed by atomic absorption spectrophotometry in surface soil and tree bark from different districts of Abuja, Nigeria, in order to determine the atmospheric trace metal input in the area.Elevated concentrations of some of the studied metals were observed in the soil and tree bark samples from the commercial/high traffic areas of the city compared to backgroundvalues. In soil samples, the average concentration of the metals were 0.6±0.4, 18.0±4.0, 281±39, 16±4 and66±23 g g-1 dry weight for Cd, Cu, Pb, Ni and Zn, respectively, whilst the average concentrations in tree bark were 0.3±0.2, 12±4, 133±32, 13±3 and 61±10 g g-1 dry weight for Cd, Cu, Pb, Ni and Zn, respectively. The trend in trace metal levels suggested that automobile emissions are a major source of these metals as the highest concentrations of Pb and Zn were recorded in the commercial areas of the city known for their high traffic densities. The levels of metal in the study area were relativelylow compared to levels found in some larger and older cities in various countries worldwide.  相似文献   

2.
The aim of the study was to determine the extent of heavy metal pollution in the vicinity of a lead battery manufacturing plant in the Czech Republic, both in the general environment and within homes. Topsoils (0–5 cm) were sampled from 100 sites along 4 transects which crossed the battery factory, the town centre and outlying rural areas. Housedust samples were collected from 15 plant-workers' homes and 15 non plant-workers' homes located at various distances from the factory. Samples were analysed for levels of Pb, Zn, Cd, Cu, As and Sb, using ICP-AES. Soil concentrations of Pb, Cd, As and Sb peaked at the perimeter fence of the battery factory with Pb levels of up to 12 650 g g> -1. Concentrations of these metals decreased exponentially within 500 m of the plant. Whilst the battery factory does appear to be a source of all the metals with the exception of Zn, emissions do not appear to be transported to any great extent over distances of more than 0.5 km. Topsoil and housedust concentrations of Pb, Zn, Cd, Cu, As and Sb in the general Mlada Boleslav area do not appear to be significantly different from those recorded in a large scale survey of urban soils in the United Kingdom. A comparison of housedust Pb concentrations in homes of plant workers and non-plant workers suggests that there may be a small input of Pb into the home environment by battery plant employees.  相似文献   

3.
Heavy metals and organochlorine contamination were analyzed in tissues of red foxes (Vulpes vulpes) from the Province of Siena (central Italy). Mercury (Hg), cadmium (Cd) and lead (Pb) concentrations were assessed in liver tissues and the data were analyzed for differences in relation to sex and age. Overall Hg, Cd and Pb mean values were 0.16, 0.62 and 0.64 g g_1 d.w., respectively. HCB, DDT and PCB concentrations were assayed in fatty tissues and muscle. The highest levels of those pollutants were found in muscle (0.47, 1.16 and 20.2 g g_1 lipid basis of HCB, DDTs and PCBs respectively), rather than in fat (0.23, 0.49 and 7.2 g g_1 l.b. of HCB, DDTs and PCBs respectively). Pollutant accumulation was analyzed in relation to sex, age and sexual maturity of females.  相似文献   

4.
The concentration of trace metals (Cd, Cu, Pb and Zn) in a total of 144 samples of grass, soil and lower animal (earthworm, Lybrodrilus violaceous) were collected and analysed for their metallic content. Levels of cadmium ranged from 0.01–0.07 g g–1; 0.01–0.12 g g–1 and from trace–0.05 g g–1 dry weight for plant, soil and animal samples respectively. Mean concentration of copper ranged 0.10–1.48 g g–1; 0.10–2.90 g g–1 and 0.01–0.08 g g–1 for samples in similar order as above. The levels of Pb varied from 0.01–0.14 g g–1; 0.02–0.23 g g–1 and from trace–0.07 g g–1 while that of Zn ranged from 0.19–1.80 g g–1; 0.51–3.35 g g–1and 0.01–0.08 g g–1 also in the same order of samples as mentioned above. Levels of metals in soil samples were higher than the background levels with the exception of Zn but lower than European Union (EU) limits. The results generally revealed the presence of metals in plant and animal samples and metal dynamics up the food chain is highly possible. Acceptable recoveries of the spiking experiment validate the experimental protocol.  相似文献   

5.
Sediments affect the water quality substantially. The metal concentrations in sediments often reflect the degree of pollution of the aquatic environment. The sediments of Thane Creek near Bombay were analyzed for nine metals Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn on twenty stations. The average metal concentrations in the sediments were 2.29, 37.25, 39.89, 103.38, 69825.0, 860.15, 105.08, 54.08, and 169.60 g g-1 dwt respectively. The metal concentrations at certain stations were relatively higher than those of uncontaminated sediments, possibly due to industrial activity in the former area.  相似文献   

6.
Heavy metal concentrations in Hylocomium splendens collected around a metal smelter in Latvia showed very high concentrations of Zn (>200 g/g), and elevated concentrations of Pb (38.3 g/g) and Cu (18.3 g/g). In an attempt to better evaluate the potential toxicity of the high Zn concentrations, a serial elution method was used to determine the concentrations of zinc in intercellular, extracellular exchangeable cell wall, intracellular, and particle fractions. The intercellular Zn concentrations represent the water soluble component of the total concentrations, and were low with no clear trends. Zn concentrations in the extra- and intracellular and particle fractions decreased exponentially from the pollutant source. Intracellular Zn concentrations in moss close to the emission source are within the range considered to be potentially toxic, from other single element exposure studies. The proportion of Zn in the relatively insoluble particle fraction, which is least associated with environmental risk, was greater closer to the pollution source, reaching > 30% in the oldest Hylocomium splendens segments.  相似文献   

7.
An investigation was carried out to monitor Pb and Cd contamination in grazing land located near a highway. Environmental media at different distances fromhighway (soil, grass, water, cow's forage, fertilizer,manure and milk samples) were collected from three samplinglocations. Soil and grass were characterized by high metalmobility (soil with Pb: 5.25±0.71–14.59±1.17 mgkg-1, dry mass and Cd: 0.038–0.33±0.04 mg kg-1, dry mass and grass with Pb: 0.76±0.05–6.62±0.18 mg kg-1, dry mass and Cd: 0.17±0.01–0.73±0.09 mg kg-1, dry mass). One-way analysis of variane (ANOVA) was applied to find out the correlation between metal (total and bioavailable) concentrationsin the soil and the distance from roadside. In most cases, the finding showed that plants growing nearer to the highway are usually exposed to more heavy metal accumulations than those awayfrom the highway. In addition, a correlation was established between plant available metal concentrations and plant metaluptake concentrations.Analysis of fertilizer and manure showed considerable amountof metals (fertilizer with Pb: 1.53±0.06 mg kg-1 andCd: 0.038 mg kg-1 and manure with Pb: 2.55–3.34 mgkg-1 and Cd: 0.14–0.31 mg kg-1). Long termsimultaneous application of fertilizer and manure on thecommercial farm showed higher metal accumulation in the soiland plants than those of co-operative farm Considerableconcentrations of metals (Pb: 1.60–2.94 mg kg-1 andCd: 0.025–0.19 mg kg-1) were observed in fodder. The finding clearly demonstrated that there are seasonalvariation in total daily metal intake by individual cow (Pb:109.37 mg day-1 (dry), 273.47 mg day-1 (rainy) andCd: 2.02 mg day-1 (dry), 19.62 mg day-1 (rainy)).The provisional tolerable weekly intake of heavy metals incows is 390 g Pb and 28 g Cd per kg bodyweight in the rainy season and 156 g Pb and 2 gCd per kg body weight in the dry season. The levels of metals (Pb: 0.014 mg L-1 and Cd: not detectable) and bio-transferfactor (10-5–10-4) in raw milk were found to be well below the Codex Alimentarius Commissions Draft (1997). Ouranalysis revealed that improvements on farm management give significant reduction in elevated levels of Pb and Cdin soil and plants, and however leads to minimize the amountof Pb and Cd in consumed milk.  相似文献   

8.
This study examined the levels of seven heavy metals (namelyzinc, copper, cadmium, chromium, lead, manganese and iron) andtheir associations with magnetic properties in playground dustof Hong Kong. Results showed that the playground dust containedhigh concentrations of Zn (mean = 1883 g g-1), Cu(mean = 143 g g-1) and Cr (mean = 263 g g-1).Qualitative examination of dust samples under microscope indicated local traffic as one of the important pollutant sources. Magnetic measurements indicated that these anthropogenicpollutants mainly consisted of coarse-grained multidomain (MD) ferrimagnetic minerals. Superparamagnetic (SP), stable single domain (SSD) ferrimagnetic grains and non-ferrimagnetic mineralswere present in relatively small amounts. Significant correlations between heavy metals and various magnetic parametersindicated a strong affinity of heavy metals to magnetic minerals hence pointed out the potential of magnetic properties for simpleand rapid proxy indications of heavy metal pollution in playground dust.  相似文献   

9.
Cadmium (Cd) and lead (Pb) concentrations in different cigarette brands sold and/or produced in Jordan were determined by graphite furnace atomic absorption spectrometry (GF-AAS). Average levels of Cd and Pb in different cigarette brands in Jordan were 2.64 and 2.67 g g– 1 (DW), respectively. The results obtained in this study estimate the average quantity of Cd inhaled from smoking one packet of 20 cigarettes to be in the range of 3.65–7.30 g. Results suggest that the quantity of Pb inhaled of smoking one packet of 20 cigarettes, is estimated to be 0.74–2.22 g. The concentrations of Cd and Pb in cigarettes were significantly different between cigarette brands tested. Our results were compared with other worldwide studies.  相似文献   

10.
A study was conducted to determine the levels of heavy metals Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn along with physico-chemical parameters in ground waters of Aligarh city, U.P. (India). Twenty seven samples of hand pump water and twenty three samples of municipal water supply were collected from different localities of the Aligarh city, five times during the period of two months at intervals of 12 days. The samples were analysed for physico-chemical characteristics (pH, electrical conductivity, chlorides, sulphates, total hardness, total alkalinity, nitrate-nitrogen, fluoride, calcium and magnesium) and heavy metal contents. The concentrations of heavy metals in the hand pump water samples were found in the ranges of Cd (ND-5.00); Cr (ND-30.00); Cu (ND-82.50); Fe (16.80–460.00); Mn (ND-425.00); Ni (ND-25.00); Pb (ND-25.00) and Zn (28.60–775.00) g l–1. The heavy metal concentrations in the municipal water supply samples were found to be Cd (ND-5.00); Cr (ND-25.00); Cu (ND-37.50); Fe (8.00–37.50); Mn (ND-320.00); Ni (ND-25.00); Pb (ND-25.00) and Zn (2.00–271.87) g l–1.It appears from the results of these studies the concentrations of Cd, Cr, Cu, Ni, Pb, and Zn in the ground waters of the Aligarh City were found to be lower than the prescribed limits of World Health Organisation (1984), whereas the values of Fe and Mn were found above the prescribed limits in some localities. The chloride total hardness and nitrate-nitrogen were comparatively higher in the hand pump water than the municipal supply water. The reason of higher values of these parameters may be ascribed to the surface disposal of sewage wastes, wastes from metal processing industries and other house hold refuses.  相似文献   

11.
The use of a combination of electrokinetic remediation and phytoremediation to decontaminate two metal-polluted soils has been demonstrated in laboratory-scale reactors. One soil was heavily contaminated with copper, the other with cadmium and arsenic (2500 g g-1 Cu; 300-400 g g-1 Cd and 230 g g-1 As, respectively). Test reactors with twoseparated chambers, each with a capacity of 5.25 kg soil, wereconstructed, then the respective chambers were filled with eithera mixture of the polluted soil and a control topsoil (75:25) ortopsoil alone. Reactors were sown with perennial ryegrass (Lolium perenne cv Elka) and a constant voltage of 30 V was applied continually across the soils in each reactor. Soil sampling took place at the start and the end of the test run, whilst plant foliage was sampled after approximately 3 weeks (both reactors) 6 weeks (Cd soil reactor only) and at the conclusion of each test run (98 days Cu soil, 80 days Cd soil). Soil and plant metal concentrations were measured, together withsoil pH. Results showed that in both soils there was a significant re-distribution of metals from anode to cathode in the test reactors, coupled with an enhancement of plant Cu uptakein the cathode region for the Cu soil. Patterns of plant Cd uptake were less clear cut and were not as clearly related to theredistribution of Cd measured in the soil. There was significant acidification of soil at the anode in each test reactor, but soilpH in other parts of the reactor changed little during the courseof the experiment. Plant growth was affected at the anode, but was not affected in other parts of the reactor. There was no visual evidence of metal toxicity in the ryegrass in either polluted soil. Some effects on soil fungi were apparent, with a stimulation of Fusarium infection of ryegrass in the cathode region of all reactors and the appearance of sporophoresof Coprinus in the same location. It is concluded that the combination of the two techniques represents a very promising approach to the decontamination of metal polluted soils that nowrequires validation in field conditions.  相似文献   

12.
Particulate matter emissions from stack number 2 of a majorferrochrome smelter, Zimbabwe Mining and Smelting Company(ZIMASCO) were characterized and the rates at which the elementsCr, Fe, Cu and Zn and total ferrochrome dust are emitted into theatmosphere were determined. The extent of soil contamination bythe dust deposited around the smelter in the generally prevailingsoutheasterly wind direction around the smelter was carried out.The highest concentrations of Cr and Fe occurred in the fineparticulates of sizes less than 59 m whilst that of Cu and Znoccurred in the coarse particulates of size range 70-100 m.The emission rates from stack 2 were; total ferrochromeparticulates 62.17 kg h-1, Cr 6.217 kg h-1, Fe 2.423 kg h-1, Zn42 mg h-1 and 6 mg h-1 for Cu. Particulate matter was emitted at arate of 289 mg m-3 from stack number 2. This value exceeds thelegal limit of 200 mg m-3. Chromium and iron are the metalsin the largest amounts. The particles that constitute the largestproportion of the dust were in the range of 58-107.5 m. Thisis a characteristic feature of the particulate matter emissionsfrom ZIMASCO. Soils in the downwind direction from the smelterwere polluted with Cr up to a distance of about 700 m outward fromthe perimeter of the boundary of the smelter.  相似文献   

13.
The spill at `Los Frailes caused a large input of metals intothe riverine, estuarine and coastal ecosystems. Metal behaviourin natural waters can be studied both by performing fieldmeasurements, and by undertaking laboratory simulationexperiments. Here is described the behaviour of the heavymetals Zn, Cd, Pb and Cu in the Guadalquivir estuary usingincubation experiments and the results compared to thoseobtained during field assessments. If the toxic waste water hadbeen discharged untreated into the environment, it could haveraised the heavy metal concentrations in the estuary water tohigh values, such as 20.65 M for Zn and 40 × 10-3 M for Cd. These values are several times higher than thoseobtained in samples collected in the area during the monitoringof the early impact. The metals present a non-conservative behaviour, with a high loss to waters of low salinity values.  相似文献   

14.
Kidney and muscle samples were collected from 197 bovine and 33 porcine carcasses and liver and muscle from 115 poultry carcasses across the province. These tissues were analyzed for the following 13 elements, Ag, As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Sb, Se, and Zn. The intent of the study was to determine normal background levels. Tissue concentration of these elements fell into five orders of magnitude ranging from < 10 g kg–1 for Ag to over 10 mg kg–1 for Zn. Similar concentrations were observed in the three specie tissues being compared except for higher concentrations of Cd and Sb in bovine kidneys. In avian tissues Mo contents were higher in liver than muscle. When samples from all three species were grouped by age, no distinct trends were observed to indicate an increase in metal contents with age, with the exception of Cd in bovine kidneys.  相似文献   

15.
Distribution of heavy metals in plants and fish of the Yamuna river (India)   总被引:2,自引:0,他引:2  
The distribution of cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb) and zinc (Zn) in the plants and fish of Yamuna river from Delhi to Allahabad, a distance of about 840 km, at five sampling stations was determined in the year 1981. The results have shown wide variations in the heavy metal levels from one sampling station to the other. The concentrations of Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn in the plants (Eicchornia crassipes) were found to be 0.02–0.12, 2.7–21.3, 4.6–64.8, 9.8–114.0, 193.0–1835.0, 380.0–1443.0, 4.4–83.0, 4.8–30.2, and 22.1–356.5 g g-1 respectively whereas in the fish (Heteropnuestes fossilis) were found to be ND-0.40, 2.3–13.7, 3.7–26.9, 8.33–58.1, 278.3–1108.0, 81.3–213.8, 2.8–32.7, 1.4–12.8 and 101.8–364.8 gg-1 respectively on dry weight basis.  相似文献   

16.
The soils adjacent to an area of historical mining, ore processing and smelting activities reflects the historical background and a mixing of recent contamination sources. The main anthropogenic sources of metals can be connected with historical and recent mine wastes, direct atmospheric deposition from mining and smelting processes and dust particles originating from open tailings ponds. Contaminated agriculture and forest soil samples with mining and smelting related pollutants were collected at different distances from the source of emission in the Pb–Zn–Ag mining area near Olkusz, Upper Silesia to (a) compare the chemical speciation of metals in agriculture and forest soils situated at the same distance from the point source of pollution (paired sampling design), (b) to evaluate the relationship between the distance from the polluter and the retention of the metals in the soil, (c) to describe mineralogy transformation of anthropogenic soil particles in the soils, and (d) to assess the effect of deposited fly ash vs. dumped mining/smelting waste on the mobility and bioavailability of metals in the soil. Forest soils are much more affected with smelting processes than agriculture soils. However, agriculture soils suffer from the downward metal migration more than the forest soils. The maximum concentrations of Pb, Zn, and Cd were detected in a forest soil profile near the smelter and reached about 25 g kg − 1, 20 g kg − 1 and 200 mg kg − 1 for Pb, Zn and Cd, respectively. The metal pollutants from smelting processes are less stable under slightly alkaline soil pH then acidic due to the metal carbonates precipitation. Metal mobility ranges in the studied forest soils are as follows: Pb > Zn ≈ Cd for relatively circum-neutral soil pH (near the smelter), Cd > Zn > Pb for acidic soils (further from the smelter). Under relatively comparable pH conditions, the main soil properties influencing metal migration are total organic carbon and cation exchange capacity. The mobilization of Pb, Zn and Cd in soils depends on the persistence of the metal-containing particles in the atmosphere; the longer the time, the more abundant the stable forms. The dumped mining/smelting waste is less risk of easily mobilizable metal forms, however, downward metal migration especially due to the periodical leaching of the waste was observed.  相似文献   

17.
In order to assess the extent of metal contamination at rocky shores of the Canarian Archipelago, metal concentrations have been measured in Patella piperata (Gould, 1846), using the standard atomic absorption spectrophotometer technique. Ranges of elements concentrations measured (in μg g−1) found in the biota were: Cd (0.36 ± 0.26 μg g−1 dry wt.), Cu (2.05 ± 0.91 dry wt.), Pb (1.57 ± 1.14 μg g−1dry wt.) and Zn (10.37 ± 4.60 μg g−1 dry wt.). Variation in metal concentrations in Patella, was tested by using non-parametric statistical methods. Cd content had a maximum in the Archipelago Chinijo, northward of Lanzarote Island. The metal concentrations recorded at the clean stations may be considered carefully if they are used like background levels.  相似文献   

18.
The metal accumulation potential of Bacopa monnieri L. was assessed under simulated laboratory conditions. This study was carried out in mixed metals (Cu, Cd, Pb, Cr, Mn) condition and repeated exposures in artificial contaminated soil. The growing shoots were planted in garden subsoil containing 3, 16, 32, 64, 160 M each of the above metals. After 8 weeks, plants were refeeded to three times higher concentrations of each metal than initially used to assess the maximum accumulating potential of the metals. The accumulation of the metals by the root and shoot was concentration and duration dependent. The metal accumulation was considerably higher in the fine root than in the shoot and showed the following order : Mn > Cr > Cu > Cd > Pb. The plants showed high tolerance to the metals as no visible phytotoxic symptom was produced after 8 weeks. However, as a result of combined metal toxicity, chlorophyll content was reduced by 62% after 12 weeks. The highest metal concentration was lethal to the plant at 16 weeks. In view of their high tolerance, the plants of B. monnieri may be considered for the amelioration of industrially-polluted wetlands experiencing regular flushing of wastewaters.  相似文献   

19.
Beryllium concentrations in atmospheric particulate and soil samples in and around a Beryllium Processing Facility (BPF) have been measured. The mean air concentration level of beryllium in and around the fence line of the BPF is 0.48 ± 0.43 ng m-3 (n = 397) and is mostly influenced by diurnaland seasonal changes. The observed air concentration levelswere well below the prescribed ambient air quality (AAQ)standard of 10 ng m-3. The soil concentration levels ofberyllium in the study area were found to be in the range of 1.42–2.75 g g-1. The mass median aerodynamic diameter (MMAD)of beryllium aerosols in ambient air was found to be 6.9 m.Source identification using the Enrichment Factor (EF) approachindicates soil as the predominant contributory source for air concentrations at the site.  相似文献   

20.
We determined concentrations of selected trace elements inlivers, kidneys and blood samples from common eiders (Somateria mollissima borealis) from the eastern Canadianarctic during 1997 and 1998. Concentrations of totalmercury and organic mercury were generally low in the liversof these birds (less than 6 and 4 g g–1 dry wt,respectively). Selenium ranged between 11–47 g g–1 inlivers. Renal cadmium concentrations were among the highestever published for this species (range: 47–281 g g–1). The regressions of log-transformed concentrations ofthese trace elements in blood samples on those in liver orkidney were significant (all P-values < 0.05) andpositive. However, except for organic mercury (RM 2 = 0.83), the co-efficients of determination were low tomoderate (range of R 2: 0.26–0.52), suggesting poorto moderate predictive capability. Furthermore, therelationships between total mercury in blood and liverchanged between 1997 and 1998, suggesting that it would notbe possible to predict consistently, concentrations ofmercury in blood from those in liver based on samples takenin one year. Blood samples can be used to determineconcentrations of these trace elements in common eiders (andprobably other sea duck species as well). The use of bloodsamples is especially warranted when it is undesirable tokill the animal such as when working with rare or endangeredsea duck species or when the objective is to relate traceelement exposure to annual survival rates. However, thepredictive equations developed here should not be used topredict expected concentrations in one type of tissue fromthose in the other.  相似文献   

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