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1.
地表粉尘中重金属对人体的健康有着重要影响。采用电感耦合等离子体原子发射光谱-质谱法(ICP-MS)对西安市文教区地表粉尘中的重金属Pb和Cd的季节含量进行了测定。采用地质累积指数法分析了重金属的污染特征,并采用健康风险评价法对各污染源进行了风险评价。结果表明,西安市文教区地表粉尘中Pb和Cd的含量大部分超过陕西省土壤背景值,地质累积指数范围大部分小于1,属于无污染或轻度污染。而冬季地表粉尘中重金属污染高于其它季节,其中冬季地表粉尘中重金属Pb的区域受污染程度顺序为:东郊>西郊>北郊≈南郊,Cd的含量区域差别顺序为:东郊>南郊>北郊>西郊,在重金属Pb和Cd的3种同位素中,207Pb和112Cd的含量最高。Pb和Cd的日均暴露剂量最大的途径是经口误食,其中镉对人体健康的危害远高于铅。  相似文献   

2.
Metal accumulation was investigated in a range of woody species that were planted on Cd-, Zn- and Pb- polluted sites in North of France. The study is unique in that we directly compare a large number of woody species (25). The highest accumulation of Zn and Cd was found in the Salicaceae family members with up to 950 mg Zn kg?1 dry weight (DW) and 44 mg Cd kg?1 DW in leaves of Populus tremula × Populus tremuloides. Zn content was positively correlated with Cd content, both in leaves and stems. Pb concentration was generally low and was species-independent. Oak and birch species accumulated more Mn as compared to other woody species. A seasonal variation in metal accumulation could be found. Although soil compositions and metal bioavailabilities differed amongst the experimental sites chosen in this study, variation of metal concentrations within a given species was small. High bioconcentration factors for poplar and willow suggested the high potential of these species over other woody species for metal accumulation. Taken together, these data suggest that poplar and willow species are good candidates for phytoremediation programmes.  相似文献   

3.
Mining activities generate spoils and effluents with extremely high metal concentrations of heavy metals that might have adverse effects on ecosystems and human health. Therefore, information on soil and plant metal concentrations is needed to assess the severity of the pollution and develop a strategy for soil reclamation such as phytoremediation. Here, we studied soils and vegetation in three heavily contaminated sites with potential toxic metals and metalloids (Zn, Pb, Cd, As, TI) in the mining district of Les Malines in the Languedoc region (southern France). Extremely high concentrations were found at different places such as the Les Aviniéres tailing basins (up to 160,000 mg kg?C1 Zn, 90,000 mg kg?C1 Pb, 9,700 mg kg?C1 of As and 245 mg kg?C1 of Tl) near a former furnace. Metal contamination extended several kilometres away from the mine sites probably because of the transport of toxic mining residues by wind and water. Spontaneous vegetation growing on the three mine sites was highly diversified and included 116 plant species. The vegetation cover consisted of species also found in non-contaminated soils, some of which have been shown to be metal-tolerant ecotypes (Festuca arvernensis, Koeleria vallesiana and Armeria arenaria) and several Zn, Cd and Tl hyperaccumulators such as Anthyllis vulneraria, Thlaspi caerulescens, Iberis intermedia and Silene latifolia. This latter species was highlighted as a new thallium hyperaccumulator, accumulating nearly 1,500 mg kg?C1. These species represent a patrimonial interest for their potential use for the phytoremediation of toxic metal-polluted areas.  相似文献   

4.
Soils of a forest ecosystem in Berlin (West) are highly polluted by Pb and less polluted by Cd and Cu. Pb levels in earthworm species depend primarily on soil type and only secondarily on the distance from a highway crossing the forest. The dominating species Lumbricus rubellus and Dendrobaena octaedra show different body burdens especially of Cd. Liming the forest soils decreases the Pb concentrations significantly. Only in D. octaedra has body weight been found to be related to Pb; Pb has been increased from 50 mg kg–1 in small to 250 mg kg–1 in large specimens; Cu has been regulated at a more or less constant absolute level (about 0.4 pg per specimen). This species obviously regulates or accumulates the three metals in different ways. Centipedes as predators of earthworms in the sites show markedly less pollution of Pb and Cd (about 2.5 and 0.6 mg kg–1) than the worms, but higher concentrations of the essential Cu (about 40 mg kg–1). The use of earthworms as indicators of heavy metal pollution should take into account the biology of the various species, the soil type, the type and amount of organic matter as well as chemical parameters such as pH value or basic anions.  相似文献   

5.
The concentrations of Hg, Cu, Pb, Cd, and Zn accumulated by regional macrophytes were investigated in three tropical wetlands in Colombia. The studied wetlands presented different degrees of metal contamination. Cu and Zn presented the highest concentrations in sediment. Metal accumulation by plants differed among species, sites, and tissues. Metals accumulated in macrophytes were mostly accumulated in root tissues, suggesting an exclusion strategy for metal tolerance. An exception was Hg, which was accumulated mainly in leaves. The ranges of mean metal concentrations were 0.035?C0.953 mg g?1 Hg, 6.5?C250.3 mg g?1 Cu, 0.059?C0.245 mg g?1 Pb, 0.004?C0.066 mg g?1 Cd, and 31.8?363.1 mg g?1 Zn in roots and 0.033?C0.888 mg g?1 Hg, 2.2?C70.7 mg g?1 Cu, 0.005?C0.086 mg g?1 Pb, 0.001?C0.03 mg g?1 Cd, and 12.6?C140.4 mg g?1 Zn in leaves. The scarce correlations registered between metal concentration in sediment and plant tissues indicate that metal concentrations in plants depend on several factors rather than on sediment concentration only. However, when Cu and Zn sediment concentrations increased, these metal concentrations in tissues also increased in Eichhornia crassipes, Ludwigia helminthorriza, and Polygonum punctatum. These species could be proposed as Cu and Zn phytoremediators. Even though macrophytes are important metal accumulators in wetlands, sediment is the main metal compartment due to the fact that its total mass is greater than the corresponding plant biomass in a given area.  相似文献   

6.
Lygeum spartum, Zygophyllum fabago and Piptatherum miliaceum are typical plant species that grow in mine tailings in semiarid Mediterranean areas. The aim of this work was to investigate metal uptake of these species growing on neutral mine tailings under controlled conditions and their response to fertilizer additions. A neutral mine tailing (pH of soil solution of 7.1–7.2) with high total metal concentrations (9,100 and 5,200 mg kg?1 Zn and Pb, respectively) from Southern Spain was used. Soluble Zn and Pb were low (0.5 and <0.1 mg l?1, respectively) but the major cations and anions reached relatively high levels (e.g. 2,600 and 1,400 mg l?1 Cl and Na). Fertilization caused a significant increase of the plant weight for the three species and decreased metal accumulation with the exception of Cd. Roots accumulated much higher metal concentrations for the three plants than shoots, except Cd in L. spartum. Shoot concentrations for the three plants were 3–14 mg kg?1 Cd, 150–300 mg kg?1 Zn, 4–11 mg kg?1 Cu, and 1–10 mg kg?1 As, and 6–110 mg kg?1 Pb. The results indicate that neutral pH mine tailings present a suitable substrate for establishment of these native plants species and fertilizer favors this establishment. Metal accumulation in plants is relatively low despite high total soil concentrations.  相似文献   

7.
贵州铅锌冶炼区农田土壤镉铅有效性评价与预测模型研究   总被引：2，自引：1，他引：2  
张厦  宋静  高慧  张强  刘赣 《土壤》2017,49(2):328-336
农田土壤重金属的不同活性库分布和土壤-溶液分配模型能够提供重金属的生物有效性和浸出能力等信息,因而在风险评价和修复实践中非常重要。本研究采集毕节铅锌冶炼区30个历史污染农田土壤,同时在贵州省范围内采集5种类型背景土壤制成不同浓度Pb/Cd单一污染土壤;经3个月老化,分别测定由0.43 mol/L HNO_3、0.1 mol/L HCl和0.005 mol/L DTPA提取态表征的重金属反应活性库以及由0.01 mol/L CaCl_2提取态表征的直接有效库;分析铅锌冶炼区农田土壤Cd、Pb不同有效库的分布特征,建立土壤-溶液分配模型,并讨论土壤理化性质的影响。结果表明:历史污染土壤中Cd和Pb的直接有效库占全量比例分别比人工污染土壤低4倍和223倍,然而历史污染土壤Cd和Pb的反应活性库(0.43 mol/L HNO_3提取态)占全量比例要高于相应人工污染土壤中的比例。拓展Freundlich形式吸附方程能够准确描述各提取态表征的Cd和Pb活性库与土壤全量Cd和Pb的关系,尤其0.43 mol/L HNO_3提取方法能够克服土壤理化性质对土壤Cd和Pb提取的影响而与总量建立极显著的相关关系。pH依附性Freundlich吸附方程准确描述了Cd和Pb的总反应活性库分别与土壤溶液Cd和Pb的关系,对于Pb而言,还要考虑土壤有机质和有效磷的影响。本研究可为矿区农田土壤重金属污染评价、修复以及农田有效态标准的推导提供参考。  相似文献   

8.
Soil heavy metal pollution, influenced by both natural and anthropogenic factors, significantly reduces environmental quality. In this study, Cr, Ni, Cu, As, Cd, and Pb in eight different land-use soils from Patuakhali District in Bangladesh were assessed. Concentrations of Cr, Ni, Cu, As, Cd, and Pb in soils were 1-87, 5-271, 4-181, 0-80, 0.2-24.0, and 5-276 mg kg-1, respectively, measured using an inductively coupled plasma-mass spectrometer. The enrichment factor, pollution load index (PLI), and contamination factor (Cfi) of metal i were used to assess the ecological risk posed by metals in soils. The PLI ranged from 0.78 to 2.66, indicating baseline levels to progressive deterioration of soil due to metal contamination. However, Cfi of Cd ranged from 1.8 to 12.0, which showed that the studied soils were strongly impacted by Cd. Considering the severity of the potential ecological risk of a single metal, the descending order was Cd > As > Pb > Cu > Ni > Cr. Soils under all land uses showed moderate to very high potential ecological risk.  相似文献   

9.
保定市污灌区土壤的Pb、Cd污染与土壤酶活性关系研究   总被引：58，自引：0，他引：58  
刘树庆 《土壤学报》1996,33(2):175-182
本文应用一元线性与非线性回归事寻优模型，着重研究了保定市污灌区土壤重金Ｐｂ、Ｃｄ污染与土壤酶活性之间的关系。结果表明，污灌区土壤Ｐｂ、Ｃｄ含量比清灌区有明显的增加，且均高于国内外重点城市的土壤背景值，已接近或达到轻度污染程度。  相似文献   

10.
The potential use of lichens as quantitative monitors of airborne heavy metal pollution has been demonstrated by measurements of Po210, Pb, Cd, Zn, and V levels in sequential growth of the foliose lichen Pseudoparmelia baltimorensis from three localities in the greater Washington, D.C. area. Samples were dated using the growth rate measured by Lawrey and Hale (1977). Po210, Pb, and V increase with age in a given colony. Higher levels of Pb, V, Cd, and Zn are present in samples from the two more polluted sites. The retention of heavy metals is consistent with trapping by an ion exchange mechanism. Since Po210 is the daughter product of in situ decay of Pb210, accumulated from atmospheric fallout of known rate, its levels can be used to calculate trapping efficiencies of Pb and retrospective fallout rates. These rates are similar to published data from rural and urban areas.  相似文献   

11.
The effect of heavy metal pollution on Oligochaeta (Enchytraeidae and Lumbricidae) populations was studied along a pollution gradient in vicinity of Olkusz (southern Poland). The study sites, which differed in metal concentrations in the humus layer, were established in mixed-pine forests 3.5 km, 2.5 km, 3.9 km, 7.9 km and 31.9 km (reference site) from the source of pollution (zinc smelter). Enchytraeid and earthworm population density and species composition were determined from soil sampled four times from the study sites. Enchytraeidae populations consisted of nine genera and 18 species. The dominating enchytraeid species in all study sites was Cognettia sphagnetorum (approx. 90%), except for the most polluted site, where Enchytraeus, Fridericia and Henlea were the most common species diversity and heterogeneity were the highest in the most polluted site. The highest mean densities were found in the reference site (16,333 individuals m?2) and lowest in the most polluted site (3932 individuals m?2). Earthworm populations consisted of three epigeic species, and the most abundant one was Dendrobaena octaedra. Earthworms densities in all sites sampled were low. The concentrations of Zn, Pb and Cd in: humus layer, and in enchytraeids and earthworms, were the highest for the most polluted site and decreased with distance from pollution source. Density of Enchytraeidae and body loads of metals in Enchytraeidae and Lumbricidae can be employed for biomonitoring.  相似文献   

12.
汉江上游汉中段河流表层沉积物重金属污染风险评价   总被引：4，自引：0，他引：4  
通过监测汉江上游汉中段河流表层沉积物重金属Pb,Cu,Zn,Cd,Cr的浓度,分析了各元素的含量分布特征,并选用Hakanson生态风险指数法对研究区进行了环境风险评价。结果表明,汉江上游汉中段各监测点重金属富集顺序为:Cd >Zn >Pb >Cr >Cu。单个重金属的污染指数Cfi显示,汉江上游汉中段监测点仅有Cu的含量均值为0.83,小于1,为轻微污染;Pb,Zn,Cd,Cr的均值分别为1.06,1.25,1.33,1.02,略大于等于1,处于轻微污染以上水平,达到中度污染水平。综合分析多项重金属污染系数Cd,单项重金属的潜在生态风险系数Eri和多种重金属的生态系统的潜在生态风险指数IR可知,汉江上游汉中段各监测点沉积物重金属污染属于轻微生态危害。  相似文献   

13.
This study was conducted to investigate the relationship between ground-dwelling spider communities and the degree of soil contamination of heavy metals, Cd and Pb. Six sites were selected according to expected differences in Cd and Pb contamination levels in soil and similarity in vegetation composition. Ground-dwelling spiders were collected monthly in 2003 and 2004 by pitfall trapping. Species diversity of ground-dwelling spiders between unpolluted and moderately polluted sites was not significantly different although the value was higher in the unpolluted site. Species diversity tended to decrease with increasing Pb levels in soil although no statistical significance was obtained. No trend was shown between species diversity and Cd levels in soil. The community structure of ground-dwelling spiders was similar for the two types of sites. Overall ground-dwelling spider communities may be not sensitive enough to discriminate moderate heavy metal contamination levels in soil. However, among the dominant spider families, the composition and structure of Linyphiidae separated unpolluted and moderately polluted sites. Pardosa astrigera and P. laura (Lycosidae) have a potential as heavy metal accumulator indicator species and Oedothorax insulanus (Linyphiidae) has a potential as a heavy metal sentinel indicator species.  相似文献   

14.
The Nyabugogo natural wetland (Kigali City, Rwanda) receives all kinds of untreated wastewaters, including those from industrial areas. This study monitored heavy metal concentrations (Cd, Cr, Cu, Pb, and Zn) in all environmental compartments of the swamp: water and sediment, the dominant plant species Cyperus papyrus, and fish (Clarias sp. and Oreochromis sp.) and Oligochaetes. Cr, Cu, and Zn concentrations in the water were generally below the WHO (2008) drinking water standards, whereas Cd and Pb were consistently above these limits. Except Cd, all metal concentrations were below the threshold levels for irrigation. The highest metal accumulation occurred in the sediment with up to 4.2 mg/kg for Cd, 68 mg/kg for Cu, 58.3 mg/kg for Pb, and 188.0 mg/kg for Zn, followed by accumulation in the roots of C. papyrus with up to 4.2 mg/kg for Cd, 45.8 mg/kg for Cr, 29.7 mg/kg for Cu, and 56.1 mg/kg for Pb. Except Cu and Zn, other heavy metal (Cd, Cr, and Pb) concentrations were high in Clarias sp., Oreochromis sp., and Oligochaetes. Therefore, there is a human health concern for people using water and products from the swamp.  相似文献   

15.
Glomalin is a metal-sorbing glycoprotein excreted by arbuscular mycorrhizal fungi (AMF). One method of estimating glomalin in soils is as glomalin-related soil protein (GRSP). In this study the role of GRSP in sequestering Pb and Cd was investigated in an in situ field experiment. The effect of metal sequestration on the subsequent decomposition of GRSP was also investigated. GRSP was determined using the Bradford method as total glomalin-related soil protein (T-GRSP) and as easily extractable glomalin-related soil protein (EE-GRSP). After 140 days, GRSP bound Pb accounted for 0.21–1.78% of the total Pb, and GRSP bound Cd accounted for 0.38–0.98% of the total Cd content in the soil. However when compared on a soil organic matter (SOM) basis, only 4% of the Pb or Cd was bound to the GRSP fraction of the SOM compared with 40–54% of the Pb or Cd bound to the humin and fulvic acids in the SOM fraction. In soils contaminated with the highest levels of Pb and Cd, the T-GRSP (EE-GRSP) decomposition after 140 days was reduced by 8.0 (6.6)% and 7.0 (7.5)%, respectively, when compared with the controls. In the high Pb or Cd treatment groups we found that the fraction of metal bound to GRSP increased even though the total GRSP content declined over time. The mass ratio between Pb and GRSP-carbon changed from 2.3 to 271.4 mg (100 g)−1 in all Pb levels soil, while with the high-Cd treatment group the mass ratio between Cd and GRSP-carbon (0.36 mg (100 g)−1) was higher than the mass ratio seen with Cd-bound humic acid fractions. Our in situ field study shows that while GRSP does bind Pb and Cd, in the soils we investigated, the levels are insignificant compared to soil organic matter such as humic and fulvic acids.  相似文献   

16.
Impacts of heavy metal concentrations in sediments on the gastropod community structure were assessed in the coastal waters of Dumai, Sumatra, Indonesia. The objective of this study was to relate the levels of heavy metal pollution with the changes of gastropod community structure in the study area. Concentrations of Cd, Cu, Pb, Zn, Ni, and Fe in surface sediments collected from five sampling stations were analyzed and correlated with the abundance, species richness, and diversity of gastropod populations. Sediments at stations with more anthropogenic activities accumulated higher concentrations of heavy metals and consequently displayed lower abundances, lower species richness and diversity; while stations with lower heavy metal concentrations in sediments showed the opposite pattern in gastropod community metrics. The above findings are complemented by significant negative correlations p?<?0.05–0.01) between concentrations of Cd, Cu, Pb, Zn, and Ni in the sediments and gastropod abundance and species richness. Among the metals analyzed, Cu and Zn had strongest negative correlations with the gastropod diversity which suggests that these metals may be the most detrimental to gastropod populations in the mangrove area of Dumai coastal waters.  相似文献   

17.
Metal pollution is an important concern because of its potential to affect human health. Metals such as lead and cadmium can enter soil via the food chain and exceed normal limits, producing harmful effects. In this study, six common garden and residential plant species were grown in soils from Spelter, WV, USA, contaminated with a variety of metals including lead (Pb), zinc (Zn), cadmium (Cd), and copper (Cu). Plant species included radish, carrot, chicory, spinach, lettuce, and clover. Metal concentrations in plant tissues were compared with metal concentration in soil by a multi‐step chemical extraction. The largest accumulation of Pb (126 mg kg−1) and Zn (1493 mg kg−1) was seen in radish roots, with Cd (40 mg kg−1) having the largest accumulation in carrot roots. Comparisons of plant availability with soil chemical extractions indicated that the combined soluble and exchangeable fractions could estimate available Zn and Cd for all six plant species. For Pb and Cu, however, the comparisons indicate that these two elements were not readily available in Spelter soils. A health risk assessment was carried out for residents at Spelter on the basis of edible tissue concentrations and publicly available consumption data. Uptake of Cd by carrot roots was about five times more than the regulatory limits for men, eight times more for women, and 12 times more for children. On the basis of the results, carrot and lettuce grown in these soils have the potential to cause toxicological problems in men, women, and young children resulting from Cd and Zn accumulation. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

18.
Metal processing at a Cu-Cd refinery at Prescot in N.W. England has led to severe contamination of the surrounding soils and vegetation, although Cu and Cd in bulk deposition declined dramatically between 1975 and 1990. Despite high spatial and temporal variability in metal deposition, mean Cd concentrations in annual tree rings of sycamore (Acer pseudoplatanus L.), lime (Tilia europaea L.) and beech (Fagus sylvatica L.) at Prescot were correlated with annual bulk Cd deposition. In contrast, mean Cd concentrations in ash (Fraxinus excelsior L.) were unrelated to Cd deposition and there was no significant relationship between mean Cu concentrations in tree rings and Cu deposition in any species. Mean Pb concentrations in sycamore, lime and beech at Prescot and the reference site also decreased over time. At Prescot however, Cd concentrations in tree rings formed in the mid 1990s were up to 10-fold higher than the reference site despite Cd deposition values during this period that were typical of levels expected for urban areas in the UK. The high Cd concentrations in wood during this period indicate that the majority of Cd in tree rings at Prescot is derived from soil, limiting the usefulness of dendrochemistry for monitoring temporal changes in metal deposition. It appears that trees are not simply passive recorders of metal deposition and other possibilities, in addition to decreasing atmospheric deposition, may explain the patterns of Cd and Pb found in sycamore, lime and beech. More research on the physiology of metal cycling in trees is required before dendrochemical techniques can be applied with confidence in environmental monitoring programs.  相似文献   

19.

Purpose

The metal concentrations and Pb isotopic composition in sediments and plants from the Xiangjiang River, China, were investigated to understand the contamination and potential toxicity of metals in sediments; to determine the accumulation and distribution of metals in plant tissues; and to trace the possible pollution source of Pb in sediments and plants.

Materials and methods

Sediments and plants were collected from 43 sampling sites in the study region. After sediments were air-dried and passed through a 63-??m sieve, they were acid-digested and DTPA-extracted for determination of total and bioavailable metals. The plants were separated into roots, leaves, and stems; dried; cut into pieces; and digested with HNO3?CH2O2. Metals (As, Cd, Cr, Cu, Ni, Pb, and Zn) and Pb isotopic composition were analyzed by inductively coupled plasma-mass spectrometry.

Results and discussion

Maximum As, Cd, Cr, Cu, Ni, Pb, and Zn concentrations in sediments were 47.18, 55.81, 129.5, 161.6, 160.4, 430.7, and 1,098.8?mg?kg?1, respectively. The bioavailable fractions of As, Cd, Cu, Pb, and Zn had significant linear relationship with their corresponding total contents in sediments while no significant relationship was observed between bioavailable and total contents of Cr and Ni. In general, plant tissues showed higher As, Cd, Cu, Pb, and Zn concentrations and lower Cr and Ni concentrations compared with sediments. The 206Pb/207Pb ratios decreased in the order of total > bioavailable > stems ?? leaves > roots. A strong linear correlation was observed between the 208Pb/206Pb and 206Pb/207Pb ratios of the plant tissues, sediments, and the possible pollution sources of Pb in the Xiangjiang River.

Conclusions

As, Cd, Cu, Pb, and Zn demonstrated higher contamination levels in sediments and plants compared with Cr and Ni. Cd had highest potential ecological risk. The Pb from anthropogenic sources with low 206Pb/207Pb ratios was preferentially associated with the bioavailable fractions in sediments and accumulated in roots. The Pb in plant tissues is mainly derived from the Pb in sediment and is taken up through the sediment-to-root pathway.  相似文献   

20.
The effect of added heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) on the rate of decomposition of glutamic acid was studied in four Dutch soil types in order to determine if such measurements would serve as sensitive indicators of heavy metal pollution in soil. The time required to reach the maximum respiration rate (referred to as the decomposition time) with glutamic acid was linearly related to increasing concentrations of Ni in a sandy loam soil.Changes in decomposition time were measured 18 months after addition of 55, 400 or 1000 mg kg? of Cd, Cr, Cu, Ni, Pb or Zn respectively to sand, silty loam, clay and sandy peat soils. A significant increase in the decomposition time occurred with a concentration of 55 mg kg?1 of Cd, Cu or Zn in the sand soil. At 400mgkg?1 adverse effects in the various soils are distinct. The sensitivity of the decomposition time of glutamic acid as a method to measure soil pollution is discussed.  相似文献   

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