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1.
The relationship between ambient concentrations of fine particulate matter and detrimental health effects remains a highly controversial issue. Increased incidence of mortality and morbidity due to cardiopulmonary complications has been associated with elevated levels of urban air particles with an aerodynamic of <2.5 ??m (PM2.5). The main aim of this paper was to present the assessment of the temporal and spatial variations of the PM2.5 fraction and its contents in arsenic, cadmium, nickel and lead in order to identify possible emission sources of these pollutants. Daily ambient aerosol samples (PM2.5) were taken in the province of Castellón from 2008 to 2009. Particle concentration levels were determined by gravimetry, and the As, Cd, Ni and Pb levels in the samples were determined by inductively coupled plasma mass spectroscopy. The season variation of these pollutants differs according to the emission source and the factors involved in dispersion. In the weekly trend, there were no significant differences in levels among sampling sites in relation to the day activity (working vs. non-working) due to chemical pollutants that are found in fine particulate fractions residing in the atmosphere longer than coarse particles, resulting in a more homogeneous concentration of pollutants over time. In order to identify similar behaviour between chemical pollutants and PM2.5, an assessment of the correlation between them was carried out. This behaviour study shows whether the source of contaminants is the same. A statistical analysis of the levels of PM2.5 and the presence of As, Cd, Ni and Pb in the different sampling sites was performed in order to evaluate the influence of the sampling point on the concentrations of these pollutants.  相似文献   

2.
Escrig  I.  Morell  I. 《Water, air, and soil pollution》1998,105(3-4):507-520
Castellón Plain is a natural area with an extension of 464 km2, situated in Castellón (eastern coast of Spain), with an important number of ceramic industries which generate waste waters containing cadmium and zinc. In this paper, equilibrium adsorption isotherms have been obtained to examine the behaviour of cadmium and zinc in three selected soils of Castellón Plain (Spain) by means of batch experiments. Both metals exhibit non-linear adsorption isotherms with adsorption maximum beyond the dissolved concentration range considered in this study. Statistical analysis showed that data fit slighty better to Freundlich linearization than that of Langmuir. Adsorption coefficients obtained from Freundlich approximation were calculated to evaluate the relative cadmium and zinc distribution between solution and studied soils obtaining coefficients ranging from 5200 to 5900 μg kg-1μg l-1 -n for cadmium and from 3500 to 43200 μg kg-1μg l-1 -n for zinc. The effects of salt concentration and calcium competition for adsorption sites were investigated providing different concentrations of CaCl2 in background solutions. Adsorption capacities of cadmium and zinc in the studied soils decreased when the salt concentration increased. A tenfold increase in calcium concentration reduced the cadmium adsorption capacity approximately by one third whereas the Ca2+ ion does not seem a significant competitor with Zn2+ for adsorption sites in soils with high organic matter content, where precipitation of zinc can be expected.  相似文献   

3.
Lotus japonicus was used to study the distribution and interconnections of 15 elements in plant tissues, including essential and non-essential elements: boron (B), sodium (Na), magnesium (Mg), potassium (K), calcium (Ca), manganese (Mn), iron (Fe), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), strontium (Sr), molybdenum (Mo), cadmium (Cd) and cesium (Cs). Large amounts of B and Ca accumulated in plant leaves, while Fe, Na, Ni, As and Cd tended to mainly occur in the roots, and Mo was the only element to accumulate in the stems. The elemental compositions within plants were severely disturbed by treatment with toxic elements. Competition between element pairs in the same group (e.g. K and Cs; Ca and Sr) was not found. Iron, Cu and Zn accumulation were induced by Cd and Ni addition. When natural variants grew in a nutrition solution with subtoxic levels of As, Cd, Cs, Ni, Mo and Sr, intriguing relationships between the elements (such as Fe, As and K; Mg and Ni; Mn and Ca) were revealed using principal-component analysis. This study on the plant ionome offers detailed information of element interactions and indicates that chemically different elements might be closely linked in uptake or translocation systems.  相似文献   

4.
Abstract

We evaluated the effects of long-term fertilization on heavy metals in soil and wheat grain under no-fertilizer control (CK), nitrogen, phosphorus, and potassium fertilizers (NPK), NPK plus straw (NPKS), and NPK plus manure (NPKM) treatments. Total lead (Pb) significantly increased in the CK over the initial soil. All fertilization treatments increased soil total arsenic (As) than CK, and the NPKM increased total cadmium (Cd), copper (Cu), and zinc (Zn) than NPK. All fertilization treatments increased soil available As and Cd than CK, and the NPKM increased available As and chromium (Cr) than NPK. The NPKS decreased grain As, Cd, Cu, and bran Cr, Zn, and Pb; but the NPKM increased grain Cr, Pb, and bran As, and Cu than NPK. Under current manure fertilization systems, the maximum bearing year of soil for As, Cr, Cd, Cu, Zn, and nickel (Ni) was 1136, 2990, 694, 1530, 910, and 1555?years, respectively.  相似文献   

5.
为筛选出适宜有色金属冶炼厂周边砷镉污染土壤的复合钝化材料,通过模拟试验,研究2,4,6-三巯基均三嗪三钠(TMT)、铁盐、黏土矿物、铝基材料等材料钝化土壤Cd和As的最优复配配方。结果显示,相同实验条件下,添加C1、C2、C3三种钝化材料后,有色金属冶炼厂周边土壤酸浸出溶液中砷、镉浓度均符合了《地表水环境质量标准》(GB 3838-2002)Ⅳ类环境质量标准。随着时间的推移,添加1.0%的C3材料(铁盐+铝基材料+ TMT)钝化重金属砷镉效果最好。其中,砷酸浸提态含量降低率最高达到了96.95%,镉酸浸提态含量降低率最高达到了99.37%。通过形态分析可以看出C3钝化材料能使重金属砷镉的形态从可交换态、铁锰氧化物结合态慢慢向残渣态的形态转移,起到了同时钝化 As、Cd 的效果,降低了砷镉重金属的迁移能力,减少冶炼厂周边砷镉重金属污染环境风险。  相似文献   

6.
Since the beginning of the twentieth century, the province of Castellón, in eastern Spain, has been one of the most important areas of floor and wall tile production on both a national and worldwide scale. As a result of this sector??s productive rate of development (in the 1970?C2005 interval), a series of pollution-producing chemical substances has been introduced into the atmosphere. The objective of this study is the comparison between industrial?Curban and rural zones in this province, with the goal of establishing the causes of the contamination in order to apply corrective measures upon the different emission sources. Sustainable development is sought after to guarantee that, in the future, the environmental quality parameters fall within legal limits, ensuring the population??s well-being as well as conserving natural ecosystems and material assets. Total suspended particles and PM10 are the parameters studied. The reason for choosing this pollutant type is because particulate matter may present a much higher potential risk despite its low representativeness as compared to the gas pollutant??s group. A positive correlation between high particle concentrations and deterioration in public health has been shown in recent studies. The elements As, Cd, Ni, and Pb in PM10 were also analyzed to determine the toxicity of these particles. This study has demonstrated the different behaviors of the parameters studied at different types of stations (industrial?Curban and rural), leading to the conclusion that anthropogenic factors are very important in the area studied and that they determine the area??s air quality to a great extent.  相似文献   

7.
Metals, as well as other air toxic pollutants, can be responsible for a range of human health effects via inhalation or ingestion. European normatives regulate lead, arsenic, cadmium, mercury and nickel ambient air levels in order to prevent potential damage to human health and ecosystems; annual target levels of 500, 6, 5 and 20?ng/m3 for Pb, As, Cd and Ni are set for these pollutants in directives 2008/50/CE and 2004/107/CE. Air quality models constitute a powerful tool to understand tropospheric dynamic and to assign concentration values to areas where no measurement is available. However, not many models include heavy metals in their code, and mainly results for Pb, Cd and Hg have been published. In this paper, we present preliminary results on modelling Pb, Cd, As, Ni, Cu, Zn, Cr and Se air background concentration in Europe using the CHIMERE model, at a 0.2° resolution and the evaluation of the model performance in order to see its capability to reproduce observed levels. This evaluation was performed by comparing simulated values with observations at the EMEP monitoring sites, as only values at background sites can be captured at the 0.2° model resolution. Important uncertainties mainly related to emissions should be solved in order to obtain an improvement of model performance; more recent annual totals, information on snap activities for each metal, higher spatial resolution and a better knowledge of the temporal emission behaviour is necessary to adequately model these air pollutants. Also a better treatment of these particles considering more realistic metal size distribution, more refined deposition processes or some chemical processes regarding Se could result in better model results. A larger number of stations and a better temporal coverage of observations are also important to carry out a better statistical analysis of model performance.  相似文献   

8.
Inductively coupled plasma optical emission spectroscopy, in combination with calculation of various biological factors, was used in this study not only for a simple illustration of the present status of some essential and non-essential metals such as copper (Cu), zinc (Zn), nickel (Ni), lead (Pb), arsenic (As), and cadmium (Cd) in the grapevine cultivar Rkatsiteli and wild blackberry from East Serbia but also for the estimation of plant bioaccumulation potentials. Great majority of detected metal concentrations were in normal ranges except in few cases: Zn concentrations were at the level of deficiency in almost all plant parts, and some Cu and As concentrations were at the levels that could be considered phytotoxic. Biological accumulation factors provided very informative data on metal accumulation and translocation in both plants and pointed to low accumulation rates of metals except in the case of Cu, Zn, and As in some wild blackberry tissues.  相似文献   

9.
广东省典型区域蔬菜重金属含量特征与污染评价   总被引:8,自引:0,他引:8  
以广东省典型区域湛江市、中山市、珠海市、东莞市、惠州市和佛山市顺德区为研究对象,通过对其大型蔬菜基地生产中5类22种蔬菜171个样品中8种重金属元素进行检测,用国家蔬菜卫生标准计算污染指数并进行评价。结果表明:蔬菜中Cu、Zn、Ni、Cr、Pb、Cd、As和Hg的平均含量分别为0.6718、3.7431、0.1928、0.1451、0.0776、0.0205、0.0825和0.0022mgkg-1,其中有13.45%的蔬菜样品受到不同程度的重金属污染,Cd和Pb是蔬菜中主要污染元素;叶菜类蔬菜中重金属含量和综合污染指数都高于豆类、块根类、瓜类和茄果类等类型蔬菜;蔬菜中的重金属含量存在着复合污染关系。  相似文献   

10.
An investigative study was conducted to determine the heavy metal pollution in the sediment in the Pra Basin of Ghana from 27 sampling points during the dry and wet seasons using the geo-accumulation index (Igeo), enrichment factor (EF), and pollution load index (PLI). Sediments were acid digested and analyzed for the following selected metals: arsenic (As), lead (Pb), cadmium (Cd), zinc (Zn), manganese (Mn), total chromium (Cr), nickel (Ni), and iron (Fe) using the dual atomizer and hydride generator atomic absorption spectrophotometer (model ASC-7000 No A309654, Shimadzu, Japan). The metal concentrations (mg kg?1) in the sediments were as follows: As (0.175)?<?Cd (3.206)?<?Ni (79.927)?<?Zn (118.323)?<?Cr (216.708)?<?Mn (234.742)?<?Pb (335.381)?<?Fe (1354.513) in the dry season and As (0.002)?<?Cd (7.279)?<?Ni (72.663)?<?Zn (35.622)?<?Pb (135.863)?<?Cr (167.604)?<?Mn (183.904)?<?Fe (1138.551) for the wet season. The EF which is an indication of whether metal concentrations are due to anthropogenic activities shows enrichment at all site for the metals Cr, Pb, and Cd in the wet seasons. However, only 4 out of the 27 sites showed Ni enrichment in the wet season. Contrary to the wet season, only Pb and Cr recorded enrichment at all sites during the dry season. Fifteen out of the 27 sites recorded Cd enrichment and 24 out of the 27 sites recorded Ni enriched during the dry season. None of the sites were enriched with Fe, As, Zn, and Mn in either the dry or wet seasons. For both dry and wet seasons, the pollution load index for all the sites except one was at the background levels which is a sign of non-deterioration of the sites studied. In the wet season, the calculated Igeo reveals that the study area is not contaminated with respect to As, Zn, Fe, and Mn; uncontaminated to moderately contaminated with Cd; moderately contaminated with Cr; uncontaminated to moderately to heavily contaminated with Ni; and moderately to heavily contaminated with Pb. The dry season Igeo results reveal non-contamination of the study area with respect to As, Fe, and Mn; uncontaminated to moderately contaminated with Zn; moderately contaminated with Cr; uncontaminated to heavily contaminated with Cd; uncontaminated to extremely contaminated with Ni; and moderately to extremely contaminated with Pb. The high levels of Cd, Pb, and Cr in all the sites are due to unregulated illegal mining activities occurring in and around the study area. It is hoped that this study will prompt the basin management board to improve their management strategies in controlling unregulated illegal mining in the basin sediments.  相似文献   

11.
工业发达城市区域耕地土壤重金属时空变异与来源变化   总被引:10,自引:5,他引:10  
为研究耕地土壤重金属随着社会经济的发展所表现出的时空变异与来源变化规律,以东莞市为研究区,通过多元统计对2002年和2012年耕地土壤中8种主要重金属元素的含量特征进行描述,并结合地统计分析和主成份分析/绝对主成分分数模型对Hg、Cd、Cu、Ni 4种污染元素的时空变异和来源变化进行分析。结果表明:除Hg外,4种污染元素含量在10 a期间均呈升高趋势。半变异分析表明,Hg、Cd和Cu在2012年受到更强的人为干扰。随着经济社会发展Hg和Cd的主要污染来源由电镀、电子、化工、制革产业和道路交通转变为电镀、电子产业与生活垃圾,导致这一转变的原因主要是政府污染整治力度的不断增加,交通环保技术的不断提高以及城市化导致的生活垃圾污染不断加剧。  相似文献   

12.
Elevated concentrations of potentially toxic trace elements in agricultural soils contribute to soil pollution affecting food quality and safety. We assessed pollution levels in agricultural systems, lowland rice (LL) and highland cash crops (HL), by comparing with non-agricultural soils (NA). Correlation analysis and principal component analysis (PCA) were performed, and geo-accumulation index (Igeo) and pollution loading index (PLI) were calculated. Zinc in LL, and Cd in LL and HL, were significantly higher than in NA. The Igeo values of cooper (Cu), lead (Pb), nickel (Ni), zinc (Zn), and cadmium (Cd) ranged from uncontaminated to moderately contaminated (Class 0 to 2) for LL, HL, and NA. Overall, trace element levels were categorized as unpolluted based on PLI. Soil properties significantly correlated with Cu, Pb, Ni, and Zn concentrations but not with Cd. Based on PCA, sources of origin for Cu, Pb, Ni, and Zn were lithogenic, while the sources for Cd was anthropogenic in the studied agricultural soils.  相似文献   

13.
Concentrations of aluminium (Al), arsenic (As), calcium (Ca), cadmium (Cd), chlorine (Cl), chromium (Cr), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), nickel (Ni), phosphorus (P), lead (Pb), sulphur (S), silicon (Si) and zinc (Zn) were measured by X-ray fluorescence spectrometry (XRF) in Scots pine needles collected from transects across Finnish Lapland and the Kola Peninsula in Russia. Ni, Cu, Fe, P and S concentrations were significantly higher in the needles collected in the vicinity of the smelters in Monchegorsk, whereas Mn and Zn decreased towards Monchegorsk. No distinct increase of S or decrease of Mn and Zn concentrations in the needles were observed when approaching Nikel. Foliar S concentrations were higher in C needles than in C+1 needles, even in plots close to the smelters. The effect of the emissions from the smelters was clearly seen in the needle chemistry up to 50 km away from smelters and was still perceivable over 100 km away.  相似文献   

14.
Alyssum pintodasilvae Dudley is a nickel (Ni) hyperaccumulator endemic to serpentine soils of north‐east Portugal. In one experiment, the effects of cadmium (Cd), chromium (Cr), copper (Cu), Ni, lead (Pb), and zinc (Zn) on the growth and mineral composition of this species were evaluated. The growth of A. pintodasilvae, measured by dry matter accumulation, was not influenced by the presence of Cr, Cu, Pb, Ni, or Zn in the soil, but Cd applications led to significant decreases in dry matter yield. The addition of heavy metals to the soil resulted in increased uptake and translocation by A. pintodasilvae but only Ni was accumulated to high levels. In a second experiment, two cuts of A. pintodasilvae, grown on a Ni‐enriched soil, were compared. Nickel concentrations were higher in the second cut, suggesting the possibility of continued growth and harvest of this plant to detoxify Ni‐contaminated soils.  相似文献   

15.
Abstract

The effect of sewage sludge applications on extractability and uptake by chard and lettuce of soil cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), leaf (Pb), and zinc (Zn) was investigated. Ten different treatments (0, 150, 300, and 500 kg N ha‐1) as mineral fertilizer, and 400, 800, and 1,200 kg N ha‐1 of aerobically and anaerobically‐digested sewage sludges were applied annually to a sandy‐loam soil since 1984. Seven years after the start of the treatments, higher levels of heavy metals were detected in the soil, depending on the type of metal, depth of sampling, type of sludge used, and, especially, rate of application. Following a sequential extraction procedure incorporating 0.1M CaCl2, 0.5M NaOH, and 0.05M Na2EDTA, most of the heavy metals in soil were detected in the Na2EDTA solution and the residual fractions. Large amounts of Cd appeared to be extracted by CaCl2, whereas substantial amounts of Cu and Ni were isolated by NaOH. The effect of treatments on the percentages of the metals found in each fraction depended on the type of metal, sampling depth, sludge used, and application rate. No significant increases were found in the heavy metal contents of chard and lettuce leaves, but some of the treatments resulted in a significant decrease of Cd and Cr levels in lettuce leaves.  相似文献   

16.
Soil fertility exerts a direct influence on the essential micronutrient contents of food crops. The focus in this study was on the role that long-term inorganic fertilization (nitrogen (N), phosphorous (P) and potassium (K)) plays in increasing the micronutrient output of the paddy cropping system. After more than 45 years of inorganic fertilizer application, the combined application of fertilizers (PK > NP > NK) substantially increased As (arsenic), B (boron), Cd (cadmium), Co (cobalt), Cr (chromium), Cu (copper), Fe (iron), Mn (manganese), Mo (molybdenum), Ni (nickel), Se (selenium), V (vanadium) and Zn (zinc) density in the soil and rice grain. Optimized and continuous application of PK fertilizers increased the overall micronutrient densities in rice milling fractions (grain and bran). Micronutrient concentrations were usually the highest in bran. Both grain and bran were rich in Fe, Mn and Zn. Correlation analysis indicated that soil pH and organic matter exert a significant and direct effect on the micronutrient concentration of rice. Although long-term fertilization enhanced the proportion of micronutrients in rice grain, the levels were still much lower than the recommended dietary intake levels for micronutrients. We therefore suggest high consumption levels of brown rice (with micronutrient-dense bran layer) because they may increase the daily intake level of micronutrients and meet the nutritional requirements that people need for sound health.  相似文献   

17.
The selective recovery of Cd from simulated spent nickel–cadmium battery solutions was achieved using a Cd working electrode in a laboratory cell with a three-electrode arrangement in hydrochloric, nitric, and sulfuric acids. The latter was selected for further study of the recovery step. Nitrate media were found to be unsuitable for Cd recovery since nitrates are reduced at the required deposition potentials. Cd(II) deposition on Cd electrodes is favored in sulfate or chloride media since it occurs at a potential some 200 mV less negative than that of Ni(II). A good percent Cd recovery (>90%) with high selectivity (approximately 0% Ni) and a reasonably high current efficiency (>80%) can be achieved under appropriate conditions. The irreversible nature of Ni(II) reduction provides the necessary framework to achieve such a selective separation.  相似文献   

18.
The effects of heavy metals [chromoium (Cr), cadmium (Cd), lead (Pb) and nickel (Ni)] on the yield, khusimol content in the essential oil, accumulation of metals, and rhizosphere microflora of vetiver (Vetiveria zizanoides) were studied in a pot experiment. The shoot yield and khusimol content in oil of vetiver were enhanced by the application of moderate amount of metals to soils. The application of Cr, Pb, and Ni had deleterious effects on the root and essential oil yield. The application of high levels of metals to soil had harmful effects on the bacterial and fungal counts in the rhizosphere. The concentrations of metals such as Cr, Cd, Pb, and Ni in shoot and root tissues were significantly enhanced by the application of those metals to soils. It can be concluded that the vetiver could be used as a promising crop for revegetation, soil remediation, and production of better quality essential oil in metal-contaminated soils.  相似文献   

19.
Barley seedlings were grown in hydroponic culture in the presence of toxic concentrations of cadmium (Cd), molybdenum (Mo), nickel (Ni), and zinc (Zn) and analyzed for element composition [boron (B), calcium (Ca), Cd, iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), molybdenum (Mo), nickel (Ni), phosphorus (P), and Zn]. In a first survey, heavy metal concentrations were selected which resulted in a similar inhibition of root growth. Toxic concentrations of Cd, Mo, Ni, and Zn revealed both similar and distinct effects on specific leaf and root element contents. Examples for such responses were decreasing contents in root Mn and Mg at elevated levels of all heavy metals, including Mo, in the medium. In contrast, changes in root contents of B were specific for the applied type of heavy metal stress. The heavy metal dependent changes in B, Ca, Mg, and Mn contents were studied in more detail. In some cases, severe heavy metal toxicity caused excessive accumulation or depletion of nutrient elements that may be deleterious to the plants in addition to other primary damages caused by the heavy metal ions.  相似文献   

20.
Abstract

The levels and availability of six heavy metals cadmium (Cd), cobalt (Co), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn) in calcareous orchard soils were measured in an investigation of a method for the determination of total content and extractable fraction of these metals by atomic absorption spectrometry. The digestion step was performed comparatively using two different types of heating. Cadmium, Cu, Ni, Pb, and Zn were determined by flame atomic absorption spectrometry (F‐AAS) and Cd was determined by electrothermal or graphite furnace atomic absorption spectrometry (GF‐AAS) using the method of standard addition. The detection limits, precision values, and accuracy (recovery assays) show the reliability of the method. The conditions for the determination of the extractable fraction of the metals were also optimized. Extraction time for Cd and Zn was studied, and the application of two hours of shaking was selected. The tested method was applied to real samples corresponding to highly calcareous orchard soils characteristic of the Mediterranean area. Only Zn, Cu and Pb showed high levels in their extractable forms, whereas Cd and Co had highest levels in their total contents. An important bio‐availability was observed in all the studied metals, but mainly for Cd and Pb.  相似文献   

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