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1.
Surface soils along roadsides or near to industrial areas may contain high concentrations of lead that adversely affect plant production. Lead contamination of roadside soils is generally attributed to the exhaust emissions of automobiles operating with leaded gasoline. The objectives of this study were to determine the relationships between lead accumulation in soils and the distance from the road edge, predominant wind direction and soil depth, and to define vertical and horizontal distribution patterns of lead accumulation within the study area. The lead content of soil decreased rapidly with the distance from the road, and the relationship was described by a power function. The contamination was more dependent on the predominant wind direction. Our results indicated that lead that had accumulated within the top few centimetres of soil had been mixed throughout the ploughing layer in cultivated lands. Soils within 40 m of the motorway had at least 2 to 6 times higher amounts of lead than the background level.  相似文献   

2.

Introduction  

In this study, total petroleum hydrocarbon (TPH) contents and some aliphatic and aromatic hydrocarbon concentrations were analysed in coastal sediments of hot points collected from along the Southern Black Sea Shelf.  相似文献   

3.
The contributions of heavy metals in selected vegetables through atmospheric deposition were quantified in an urban area of India. Deposition rate of Zn was recorded maximum followed by Cu, Cd and Pb. The concentrations of Zn and Cu were highest in Brassica oleracea, Cd in Abelmoschus esculentus and B. oleracea, while Pb was highest in Beta vulgaris. Heavy metal pollution index showed that B. oleracea was maximally contaminated with heavy metals followed by A. esculentus and then B. vulgaris. The results of washing showed that atmospheric deposition has contributed to the increased levels of heavy metals in vegetables. Both Cu and Cd posed health risk to local population via test vegetables consumption, whereas Pb posed the same only through B. oleracea. The study concludes that atmospheric depositions can elevate the levels of heavy metals in vegetables during marketing having potential health hazards to consumers.  相似文献   

4.
Gallipoli is a small town on the European side of the Dardanelles Strait, in Turkey. More than 450,000 soldiers gave their lives on the Gallipoli Peninsula (Gallipoli Campaign) over a nine-month period during World War I. In that war, many naval and landing bombs were exploded. The ingredients of these bombs may cause heavy metal contamination in soils. An environmental geochemical investigation has been carried out around Gallipoli Peninsula in order to determine the extent of chemical pollution in the soil. The preliminary data reveal that soils in the area are, in general, not contaminated. The concentrations of many heavy metals, such as arsenic (As), cadmium (Cd), copper (Cu), chromium (Cr), cobalt (Co), manganese (Mn), nickel (Ni), lead (Pb), strontium (Sr), vanadium (V) and zinc (Zn) are in the range of those of average agricultural soils. These low concentrations are explained by the good leaching characteristics of Oligocene–Miocene rocks, Pleistocene terrace material, alluvium sandy-silty soils, and surface run-off.  相似文献   

5.
This study evaluates the influence of a heavily urbanized area (Paris Metropolitan area), on receiving water contamination by both bisphenol A (BPA) and alkylphenol ethoxylate (APE) biodegradation product. The study began by investigating concentrations within urban sources. In addition to the more commonly studied wastewater treatment plant effluent, wet weather urban sources (including combined sewer overflows, urban runoff, and total atmospheric fallout) were considered. The initial results highlight a significant contamination of all urban sources (from a few nanograms per liter in atmospheric fallout to several micrograms per liter in the other sources) with clearly distinguishable distribution patterns. Secondly, concentration changes along the Seine River from upstream of the Paris Metropolitan area to downstream were investigated. While the concentrations of BPA and nonylphenoxy acetic acid (NP1EC) increase substantially due to urban sources, the 4-nonylphenol concentrations remain homogeneous along the Seine. These results suggest a broad dissemination of 4-nonylphenol at the scale of the Seine River basin. Moreover, the relationship between pollutant concentrations and Seine River flow was assessed both upstream and downstream of the Paris conurbation. Consequently, a sharp decrease in dissolved NP1EC concentrations relative to Seine River flow underscores the influence of single-point urban pollution on Seine River contamination. Conversely, dissolved 4-nonylphenol concentrations serve to reinforce the hypothesis of its widespread presence at the Seine River basin scale.  相似文献   

6.
Environmental Science and Pollution Research - Nitrate pollution in rivers, lakes, shallow groundwater, and even deep groundwater occurs in many parts of the world. And, it’s essential to...  相似文献   

7.
The aflatoxin contamination of some pepper types sold in Turkey   总被引:5,自引:0,他引:5  
Erdogan A 《Chemosphere》2004,56(4):321-325
In the present study, 44 red-scaled pepper and 26 red powder pepper samples obtained from various spice retailers in Erzurum, and 20 isot (red pepper produced in Sanliurfa) were investigated for aflatoxin contamination using thin layer chromatography. Aflatoxin (B + G) was found in 8 red pepper samples (18.2%), and 3 red powder peppers (10.7%), and 1 isot sample (5%). The aflatoxin amount ranged from 1.1 to 97.5 ppb in all samples investigated. The highest amount of aflatoxin was found in red-scaled pepper. Species of Aspergillus, Penicillium and Rhizopus were generally contaminants of all samples.  相似文献   

8.
Environmental Science and Pollution Research - Fluoride contamination in groundwater is a major problem throughout the world as well as in India. High-fluoride content was reported in the hot...  相似文献   

9.
A field study was performed to evaluate indoor air concentrations and vapor intrusion (VI) of tetrachloroethylene (PCE) and other chlorinated solvents at a commercial retail site in Dallas, TX. The building is approximately 40 yr old and once housed a dry cleaning operation. Results from an initial site characterization were used to select sampling locations for the VI study. The general approach for evaluating VI was to collect time-integrated canister samples for off-site U.S. Environmental Protection Agency Method TO-15 analyses. PCE and other chlorinated solvents were measured in shallow soil gas, subslab soil-gas, indoor air, and ambient air. The subslab soil gas exhibited relatively high values: PCE < or =2,600,000 parts per billion by volume (ppbv) and trichloroethylene < or =170 ppbv. The attenuation factor, the ratio of indoor air and subslab soil-gas concentrations, was unusually low: approximately 5 x 10(-6) based on the maximum subslab soil-gas concentration of PCE and 1.4 x 10(-5) based on average values.  相似文献   

10.
Detecting anthropogenic metal contamination in regional surveys can be particularly difficult when there is a lack of pre-disturbance data, especially when trying to differentiate low to moderate levels of contamination from background values. Furthermore, comparisons with other regional studies are confounded by differing analytical methods used and variations in sediment properties such as grainsize. Several types of geochemical technique, including weak acid partial extraction, strong acid extractions and total digestion have been used. Attempts have been made to overcome the influence that grainsize has on chemical concentrations in heterogeneous environments by analysing the fines, typically the mud fraction (<63 microm), in an attempt to improve the detection of anthropogenic contamination. Here we compare a weak acid partial extraction using 1M HCl and total digestion methods for a regional survey of reference and impacted sites in Antarctica using both whole sediment (<2 mm) and mud (<63 microm) fractions. The 1M partial extraction on whole sediment (<2 mm) most closely distinguished weakly, or moderately, impacted sites from reference locations. It also identified small scale within-location spatial variation in metal contamination that the total digest did not detect. Compared with total digests or analysis of the <63 microm fraction alone, this method minimised the possibility of a Type II statistical error in the regional survey - that is, failing to identify a site as being contaminated when it has elevated metal concentrations. To allow inter-regional comparison of sediment chemistry data from elsewhere in Antarctica, and also more generally, we recommend a 1M HCl partial extraction on whole sediment (<2 mm).  相似文献   

11.
A local ammonia (NH3) inventory for a 5x5 km area in central England was developed, to investigate the variability of emissions, deposition and impacts of NH3 at a field scale, as well as to assess the validity of the UK 5-km grid inventory. Input data were available for the study area for 1993 and 1996 on a field by field basis, allowing NH3 emissions to be calculated for each individual field, separately for livestock grazing, livestock housing and manure storage, landspreading of manures and fertiliser N application to crops and grassland. An existing atmospheric transport model was modified and applied to model air concentrations and deposition of NH3 at a fine spatial resolution (50 m grid). From the mapped deposition estimates and land cover information, critical loads and exceedances were derived. to study the implications of local variability for regional NH3 impacts assessments. The results show that the most extreme local variability in NH3 emissions, deposition and impacts is linked to housing and storage losses. However, landspreading of manures and intensive cattle grazing are other important area sources, which vary substantially in the landscape. Overall, the range of predicted emissions from agricultural land within the study area is 0-2000 kg N ha(-1) year(-1) in 1993 and 0-8000 kg N ha(-1) year(-1) in 1996, respectively, with the peak at a poultry farm located in the study area. On average, the estimated field level NH3 emissions over the study area closely match the emission for the equivalent 5-km grid square in the national inventory for 1996. Deposition and expected impacts are highly spatially variable, with the edges of woodland and small "islands" of semi-natural vegetation in intensive agricultural areas being most at risk from enhanced deposition. Conversely the centres of larger nature reserves receive less deposition than average. As a consequence of this local variability it is concluded that national assessments at the 5 km grid level underestimate the occurrence of critical loads exceedances due to NH3 in agricultural landscapes.  相似文献   

12.
Sue Yai Utit is an old community located in Bangkok, Thailand which dismantles waste electrical and electronic equipment (WEEE). The surface soil samples at the dismantling site were contaminated with copper (Cu), lead (Pb), zinc (Zn), and nickel (Ni) higher than Dutch Standards, especially around the WEEE dumps. Residual fractions of Cu, Pb, Zn, and Ni in coarse soil particles were greater than in finer soil. However, those metals bonded to Fe-Mn oxides were considerably greater in fine soil particles. The distribution of Zn in the mobile fraction and a higher concentration in finer soil particles indicated its readily leachable character. The concentration of Cu, Pb, and Ni in both fine and coarse soil particles was mostly not significantly different. The fractionation of heavy metals at this dismantling site was comparable to the background. The contamination characteristics differed from pollution by other sources, which generally demonstrated the magnification of the non-residual fraction. A distribution pathway was proposed whereby contamination began by the deposition of WEEE scrap directly onto the soil surface as a source of heavy metal. This then accumulated, corroded, and was released via natural processes, becoming redistributed among the soil material. Therefore, the concentrations of both the residual and non-residual fractions of heavy metals in WEEE-contaminated soil increased.  相似文献   

13.
Environmental Science and Pollution Research - Serious groundwater pollution not only affects the development of enterprises but also threatens the life and health of residents. To explore the...  相似文献   

14.
This study was designed to monitor molinate losses in surface and underground waters during Ordram application in a rice field situated in central Portugal. Water samples were collected from different sites, before, during and about one month and a half after Ordram application. Molinate quantification was based on a solid-phase microextraction (SPME) method followed by gas chromatography with flame photometric detector (GC-FPD) analysis, and led to the conclusion that the herbicide was dissipated in the environment, reaching levels as high as 3.9 microgl(-1) in underground water and 15.8 microgl(-1) in the river receiving tail waters. The feasibility of the application of treatment methodologies based on adsorption or biodegradation as processes to remove molinate from real-world waters was assessed. These methods seem suitable to reduce molinate concentrations to values in the range of the legally recommended limits (<0.5 microgl(-1)).  相似文献   

15.
The geochemical characteristics of some heavy metals (Cr, Cd, Pb, Zn and Ni) in the river and sea sediments, in the soil and in the river and groundwater of an estuary on the southeast coast of Turkey have been studied. In the sea sediments, the wastes from a chromium factory control these metal concentrations. The heavy metal contamination in the river sediments results from an existing chromite mine at the northern part of the area. These heavy metals are concentrated in the soil, but they do not penetrate into the groundwater because of the low permeability of the unsaturated zone in the region.  相似文献   

16.
In many regions of the world, biodiversity surveys are not routinely conducted prior to activities that lead to land conversion, such as development projects. Here we use top-down methods based on global range maps and bottom-up methods based on macroecological scaling laws to illuminate the otherwise hidden biodiversity impacts of three large hydroelectric dams in the state of Sarawak in northern Borneo. Our retrospective impact assessment finds that the three reservoirs inundate habitat for 331 species of birds (3 million individuals) and 164 species of mammals (110 million individuals). A minimum of 2100 species of trees (900 million individuals) and 17 700 species of arthropods (34 billion individuals) are estimated to be affected by the dams. No extinctions of bird, mammal, or tree species are expected due to habitat loss following reservoir inundation, while 4–7 arthropod species extinctions are predicted. These assessment methods are applicable to any data-limited system undergoing land-use change.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-015-0683-3) contains supplementary material, which is available to authorized users.  相似文献   

17.
A natural gradient emplaced-source (ES) controlled field experiment was conducted at the Borden aquifer research site, Ontario, to study the transport of dissolved plumes emanating from residual dense nonaqueous-phase liquid (DNAPL) source zones. The specific objective of the work presented here is to determine the effects of solute and co-solute concentrations on sorption and retardation of dissolved chlorinated solvent-contaminant plumes. The ES field experiment comprised a controlled emplacement of a residual multicomponent DNAPL below the groundwater table and intensive monitoring of dissolved-phase plumes of trichloromethane (TCM), trichloroethylene (TCE), and perchloroethylene (PCE) plumes continuously generated in the aquifer down gradient from gradual source dissolution. Estimates of plume retardation (and dispersion) were obtained from 3-D numerical simulations that incorporated transient source input and flow regimes monitored during the test. PCE, the most retarded solute, surprisingly exhibited a retardation factor approximately 3 times lower than observed in a previous Borden tracer test by Mackay et al. [Water Resour. Res. 22 (1986) 2017] conducted approximately 150 m away. Also, an absence of temporal trend in PCE retardation contrasted with the previous Borden test. Supporting laboratory studies on ES site core indicated that sorption was nonlinear and competitive, i.e. reduced sorption of PCE was observed in the presence of TCE. Consideration of the effects of relatively high co-solute (TCE) concentration (competitive sorption) in addition to PCE concentration effects (nonlinear sorption) was necessary to yield laboratory-based PCE retardation estimates consistent with the field plume values. Concentration- and co-solute-based sorption and retardation analysis was also applied to the previous low-concentration pulse injection test of Mackay et al. [Water Resour. Res. 22 (1986) 2017] and was able to successfully predict the temporal field retardation trends observed in that test. While it is acknowledged that other "nonideal transport" effects may contribute, our analysis predicts differences in the PCE retardation magnitude and trend between the two experiments that are consistent with field observations based on the marked solute concentration differences that resulted from contrasting source conditions. Solute and co-solute concentration effects have heretofore received little attention, but may have wide significance in aquifers contaminated by point-source pollutants because many plumes contain mixed solutes over wide concentration ranges in strata that are likely subject to nonlinear sorption.  相似文献   

18.
Water samples derived from two different aquifer layers of six sampling sites were analysed by GC/MS in order to characterize a groundwater contamination caused by chemicals used for wood impregnation. Mono- and dichlorinated naphthalenes, chlorobenzo(b)thiophene, 1-chloro-4-naphthol, 1-chloronaphthoic acid, acenaphthene and methyled naphthalenes were identified as the main pollutants and quantified. 1-Chloro-4-naphthol and 1-chloronaphthoic acid are discussed as possible indicators for anaerobic degradation processes. Results of inorganic and compound specific stable carbon isotope analyses revealed only a minor degree of microbiological transformation. Thus, sorption was characterized as the main attenuation process within the aquifer affecting the contamination described.  相似文献   

19.
In 2000, as part of a survey programme, the German authorities detected high levels of dioxins in a choline chloride (CC) premix used as animal food component. The contaminated additive consisted of different products of mineral and vegetable origin acting as a carrier. The CC was manufactured in Belgium. The final product was produced in and distributed from a plant in Spain. The German authorities informed all European Community members of the incident. The Spanish Ministry of Agriculture, Fisheries and Food and the Regional Authorities immediately conducted a survey in collaboration with the Spanish Council for Scientific Research (CSIC) to determine and isolate the source of the contamination. Analysis of a large number of samples of pure CC, pine sawdust, almond shell and other substances currently used in the preparation of the premix confirmed the presence of a significant amount of polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans in mixtures in which pine sawdust was present. An analysis of the congener profiles revealed similarities with those found in technical pentachlorophenol (PCP) formulations. The conclusion was that PCP-contaminated sawdust as carrier for CC was source of dioxin contamination in feedingstuff.  相似文献   

20.
The major cations, anions, and detergents in a plume of contaminated groundwater at Otis Air Base on Cape Cod (Mass., U.S.A.) have moved approximately 3.5 km down gradient from the disposal beds. We hypothesize that the detergents form two distinct plumes, which consist of alkyl benzene sulfonates (ABS) detergents and linear alkyl sulfonates (LAS) and sodium dodecyl sulfate (NaLS) detergents. The ABS detergents were deposited from approximately 1940 through 1965, when ABS detergents were banned. From 1965 to the present, LAS and NaLS detergents were in the sewage. The ABS detergents appear to be transported in the aquifer at the same rate as the specific conductance (major cations and anions) and boron, which are currently used as conservative tracers of the plume of contaminated groundwater. There appears to be little or no biological degradation of the ABS detergents in the aquifer, based on their concentration in the plume. On the other hand, the LAS and NaLS detergents have degraded rapidly and have been detected only 0.6 km down gradient. The roleof the detergents in the transport of other organic compounds in the plume is nuclear. There is a separation of the ABS detergent plume and the volatile organic compound plume; however, the time of entry of the detergents and the volatile organic compounds is unknown. Therefore, it is not possible to conclude on the interaction of these two classes of compounds.  相似文献   

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