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1.
This investigation assesses the feasibility of calculating and visualizing health risk estimates from exposure to groundwater contaminated with arsenic (As) using data from national geochemical databases. The potential health risk associated with As-contaminated groundwater was assessed based on an elaboration of existing geochemical data in accordance with accepted methodological procedures established for human health risk assessment (U.S. Environmental Protection Agency methodology). A screening analysis approach was used for estimating the contribution of As to the total chronic health risk from exposure to groundwater contaminated with potentially toxic elements, including As, Ba, Cd, Cu, Hg, Pb, Sb, Se and Zn, and the results indicate that As contributes significantly (>50%) to this total health chronic risk in about 10% of Slovak territory. Based on the calculation of the potential risk level by exposure modelling, increased chronic as well as carcinogenic risk levels (medium to high) were documented in approximately 0.2 and 11% of the total Slovak area, respectively. The areas characterized by high health risk levels are mainly those geogenically contaminated. High and very high carcinogenic risk was determined in 34 of 79 districts and in 528 of 2924 municipalities.  相似文献   

2.
This study presents an assessment of the potential impact of geological contamination of the environment on the health of the population in Spišsko-Gemerské rudohorie Mts. (SGR Mts.). The concentration levels of potentially toxic elements (mainly As, Cd, Cu, Hg, Pb, Sb, and Zn) were determined in soils, groundwater, surface water, and stream sediments as well as in the food chain (locally grown vegetables). A medical study included some 30 health indicators for all 98 municipalities of the study area. The As and Sb contents in human fluids and tissues were analyzed in one municipality identified to be at the highest risk. Based on element content, environmental and health risks were calculated for respective municipalities. Out of 98 municipalities 14 were characterized with extremely high environmental risk and 10 were characterized with very high carcinogenic risk from arsenic (groundwater). Extensive statistical analysis of geochemical data (element contents in soils, groundwater, surface water, and stream sediments) and health indicators was performed. Significant correlations between element contents in the geological environment and health indicators, mainly cancer and cardiovascular diseases, were identified. Biological monitoring has confirmed the transfer of elements from the geological environment to human fluids and tissues as well as to the local food chain.  相似文献   

3.
铜仁市土壤-玉米重金属含量及其健康风险   总被引:4,自引:0,他引:4  
周浪  张云霞  徐启翀  庞瑞  宋波 《环境化学》2021,40(1):213-222
为了解铜仁市玉米地土壤和玉米籽粒重金属的含量分布特征,并评估当地居民通过玉米籽粒摄入重金属的健康风险.于2018年7月采集了铜仁市自然土壤样品65个、玉米地土壤样品122个和玉米样品100个,并分析其Cd、Pb、Cu、Zn、Ni、As、Hg含量,通过重金属摄入量评价居民膳食暴露的健康风险.结果表明,自然土壤Cd、Pb、...  相似文献   

4.
Nine potentially harmful heavy metals (Cd, Co, Cr, Cu, Hg, Mn, Pb, Ni, and Zn) were measured in 477 topsoil samples collected from urban–rural areas in the city of Wuhan in order to identify their concentrations and possible sources, and characterize their spatial variability for risk assessment. Results showed that in most rural areas heavy-metal concentrations in soil were similar to their natural background values, but Cd, Cu, Hg, Pb, and Zn concentrations were relatively higher in densely populated districts and around industrial facilities. Multivariate analyses (correlation matrix, principal component analysis, and cluster analysis) indicated that Cd, Cu, Hg, Pb, and Zn were mainly derived from anthropogenic inputs, and Co, Cr, and Mn were controlled by natural source, whereas Ni appeared to be affected by both anthropogenic and natural sources. The result of risk assessment indicated that nearly 48% of the study area suffered from moderate to severe contamination.  相似文献   

5.
A centuries long history of mining and mineral processing has resulted in elevated Cd, Pb and Zn soil concentrations in the vicinity of the Silvermines abandoned mine site (AMS), Co. Tipperary, Ireland. A process for preliminary evaluation of environmental risk was developed and implemented. Potential pathways of metal compound transport and deposition were mapped and used to optimise the subsequent site investigation. Elevated soil metals are shown to be predominantly in areas where metal deposition in soil is associated with water related pathways (surface runoff, seasonal groundwater seepage and floodplains). Extensive areas of soil in the surrounding district are classified as contaminated on the basis of Cd, Pb and Zn concentrations, both total and potential bioavailable (EDTA-extractable). The most affected areas, with metal concentrations in soil comparable with that within the AMS, were floodplains located 2–3 km downstream from the site. Assessment of the sequential effects on grass and grazing animals indicates that Pb poses the greatest risk due to its high toxicity and high concentrations in soil (more than 10 000 mg kg–1). Within floodplain areas grazing cattle may intake a lethal dose of Pb. On the basis of the investigation an approach to risk assessment was developed which allowed quantified assessment of the risks related to individual metals, areas of contamination and contamination targets.  相似文献   

6.
In order to investigate the ecological and human health risks of metal(loid)s (Cu, Pb, Zn, Ni, Cd, Mn, Cr, and As) in peri-urban soils, 43 surface soil samples were collected from the peri-urban area around Nanjing, a megacity in China. The average contents were 1.19, 67.8, 37.6, 105, 167, 44.6, 722, and 50.8 mg kg?1 for Cd, Cr, Ni, Pb, Zn, Cu, Mn, and As, respectively. A significant positive correlation was found between Cu, Pb, Zn, Cd, Mn, and As (p < 0.01), and Cr had a significant positive correlation with Ni (p < 0.01). Geoaccumulation indices indicate the presence of Cd and As contamination in all of the peri-urban soil samples. Potential ecological risk indices show that the metal(loid)s in the soil could result in higher ecological risks. Cd is the main contributor to the risk, followed by As. The levels of Cu, Pb, Zn, Cd, Mn, and As in stomach and intestinal phases show a positive linear correlation with their total contents. Mn, Zn, Ni, Cd, and Pb in stomach phase showed higher bioaccessibility, while in intestinal phase, Cu, Cr, and As had the higher bioaccessibility. The carcinogenic risk in children and adults posed by As, Pb, and Cr via ingestion was deemed acceptable. The non-carcinogenic risks posed by these metal(loid)s via ingestion to children are higher than to adults and mainly result from As.  相似文献   

7.
润肤霜类化妆品中金属元素的测定及砷形态初探   总被引:1,自引:0,他引:1  
采用电感耦合等离子体质谱(ICP-MS)测定化妆品中的金属元素铝、铬、镍、铜、锌、砷、硒、镉、锡、锑、钡、镧、铈、镨、钕、钐、汞、铅的总量,并结合液相色谱(HPLC)-ICPMS联用技术考察了化妆品中的砷形态.研究表明,金属指标不合格的化妆品多为汞含量超标;此外,化妆品中的砷多以无机砷形式存在.  相似文献   

8.
贵阳和万山地区部分蔬菜中的重金属含量及其健康风险   总被引:8,自引:2,他引:6  
以贵州省贵阳市和万山地区为例,对购自当地自由市场的部分蔬菜中的重金属Cd、Hg、Pb、Mn、As的含量进行了测定,并以国际放射防护委员会(ICRP,International Commissionon Radiological Protection)给出的限定值为标准,对某些重金属含量超标的蔬菜进行了健康风险评价.结果表明:除个别蔬菜的As和Mn外,万山地区蔬菜中的重金属含量均明显高于贵阳地区;两地蔬菜中的As、Pb含量均低于国家限定值(GB4810-1994、GB14935-1994),而部分蔬菜中的Cd、Hg含量均明显超出国家限定值(GB15201-1994、GB2762-1994).风险评价结果表明贵阳和万山两地的蔬菜可能存在重金属Cd、Hg、Pb的中、轻度污染;存在Cd污染的蔬菜对人体的年致癌风险为3.40×10-7·a-1,非致癌物Hg和Pb对人体的总健康风险分别为3.63×10-7·a-1、1.69×10-6·a-1,均低于ICRP标准.  相似文献   

9.
Elevated concentrations of potentially toxic elements (PTEs) are usually found in areas of intense industrial activity. Thriasio Plain is a plain near Athens, Greece, where most of the heavy industry of the country has been situated for decades, but it also is a residential and horticultural area. We aimed at measuring the levels of PTEs in soils and indigenous plant species and assessing the health risk associated with direct soil ingestion. Samples of soils at roadsides and growing plants were collected from 31 sites of that area. Concentrations of Al, As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, V and Zn were measured in both soils (as pseudo-total) and aerial plant tissues. We found that As, Cd, Cr, Cu, Ni, Pb and Zn were higher than maximum regulatory limits. Element concentrations in plants were rather lower than expected, probably because indigenous plants have developed excluder behaviour over time. Copper and Zn soil-to-plant coefficients were highest among the other elements; for Cu this was unexpected, and probably associated with recent Cu-releasing industrial activity. Risk assessment analysis indicated that As was the element contributing more than 50 % of the health risk related to direct soil ingestion, followed by Cr, Pb, and, surprisingly, Mn. We concluded that in a multi-element contamination situation, elevated risk of PTEs (such as As, Cr and Pb) may reduce the tolerance limits of exposure to less-toxic elements (here, Mn).  相似文献   

10.
南京城市土壤重金属含量及空间分布特征   总被引:13,自引:0,他引:13  
研究了南京城市土壤重金属含量、来源及空间分布特征。结果表明,南京城市土壤中V、Mn、Co、Ni、Cr污染不明显,但受到了不同程度的Cu、Pb、Zn、Sb、Hg、Cd污染,其中Hg污染比较严重。V、Mn、Co、Ni、Cr含量之间均呈极显著正相父;Cu、Pb、Zn、Sb、Hg、Cd含量之间也均呈极显著正相关。南京城市土壤V、Mn、Co、Ni、Cr主要继承了原土物质;Hg、Cd、Pb主要来源于城市燃煤、机动车尾气及工厂排放粉尘;Sb主要来源于机动车尾气和工厂排放粉尘。南京城市土壤Hg、Cd、Pb、Sb含量空间分布规律非常相似,均表现为外围向市中心有逐渐增加的趋势,并且在新街口—鼓楼、梅山硫铁矿形成异常高值的岛状、环状区域。  相似文献   

11.
An assessment is presented of distribution characteristics of heavy metals in the urban topsoil from the city of Xuzhou. The concentrations of Ag, Al, As, Au, Ba, Be, Bi, Cd, Co, Cr, Cu, Fe, Ga, Hg, Li, Mn, Mo, Ni, Pb, Pd, Pt, Sb, Sc, Se, Sn, V and Zn have been determined from 21 soil samples. Examination of lognormal distribution plots indicates that the diagrams of Al, Be, Fe, Ga, Li, and V are almost linear suggesting that these metals are almost unaffected by anthropogenic activities while the plots for As, Cd, Cu, Pb, Pd, Pt, Se, Zn and others are not linear probably due to anthropogenic activities from which these metals are delivered to the soils. Al is used for mineralogical normalization of these data. An evaluation of background values for topsoil is also carried out by means of lognormal distribution plots. The results show our background values obtained from the lognormal distribution plots are comparable to those values of uncontaminated soils of Xuzhou obtained by previous work except for Cd and Hg. At present, no explanation for the exceptions Cd and Hg can be given.  相似文献   

12.
The concentrations and distributions of chemical elements (Ag, Al, As, Au, Ba, Bi, Ca, Cd, Co, Cr, Cu, Fe, Ga, Hg, K, La, Mg, Mn, Mo, Na, Ni, P, Pb, S, Sb, Sc, Se, Sr, Te, Th, Ti, Tl, U, V, W and Zn) were studied in till, humus and urban soil in Jakobstad, a small town (20,000 inhabitants) in W. Finland. The analyses were performed with ICP-MS after aqua regia leaching of till (n = 37), urban topsoil (n = 32) and subsoil (n = 32), and HNO3 leaching of humus (n = 37). The till and humus samples, collected at the same sites, were divided into urban and rural samples. The urban till was not significantly enriched in metals. In contrast, a majority of the elements occurred in higher concentrations in the urban than the rural humus samples. Statistical and spatial interpretations of the humus data revealed that traffic (Pb, V and Ni), metal industry (Pb, Zn, Bi, Sb and Cr), an abandoned shooting range (Pb and Sb) and other sources contribute to higher metal levels in the urban humus. The urban soil samples were collected at parks, yards, abandoned industrial sites, roadsides, etc. The topsoil samples were enriched in most elements, also by elements not enriched in the urban humus (e.g. Cd). At several sites, the concentrations far exceeded the limit concentrations for contaminated soils in Finland. A large variety of sources were identified or indicated.  相似文献   

13.
The objective of this study was to assess the bulk chemical composition as well as the extent and severity of heavy metal contamination in the paddy soil of Kočani Field (eastern Macedonia). The results revealed that the paddy soil of the western part of Kočani Field is severely contaminated with Pb, Zn, As and Cd in the vicinity of the Zletovska River due to irrigation with riverine water that is severely affected by acid mine and tailing effluents from the Pb–Zn mine in Zletovo. The detected total concentrations of these metals are far above the threshold values considered to be phytotoxically excessive for surface soil. The paddy soil in the vicinity of the Zletovska River was also found to exhibit elevated levels of Ba, Th, U, V, W, Mo, Cu, Sb, Bi, Ag, Au, Hg and Tl, with concentrations above their generally accepted median concentration values obtained during this study. A correlation matrix revealed that the Mn and Fe oxides/hydroxides are the most important carrier phase for several trace elements, with the exception of rare earth elements (REEs). These also represent a major sink for the observed heavy metal pollution of the soil. REEs are mostly associated with two phases: light (L)REEs are bound to K-Al, while heavy (H)REEs are bound to Mg-bearing minerals. Although there is no direct evidence of a health risk, the paddy soil in the vicinity of Zletovska River needs further investigation and an assessment should be made of its suitability for agricultural use, particularly in view of the highly elevated concentrations of Pb, Zn, As and Cd.  相似文献   

14.
宝鸡市街道灰尘重金属污染的健康风险评价   总被引:8,自引:0,他引:8  
对宝鸡市工业区、交通区和商业区等不同功能区所采集的街尘样品应用美国EPA人体暴露风险评价方法对灰尘重金属进行健康风险评价.结果表明,As、Hg、Pb、Cu、Zn、Cr、Co、Ni、Mn、V这10种重金属平均含量均高于陕西土壤背景值,其中Hg、Pb平均含量分别为陕西土壤背景值的37倍和20倍.健康风险评价表明,灰尘中10...  相似文献   

15.
In the developing world, vegetables are commonly grown in suburban areas irrigated with untreated wastewater containing potentially harmful elements (PHEs). In Pakistan, there is no published work on the bioaccessibility aspect of PHEs and dietary minerals (DMs) in sewage-irrigated soil or the vegetables grown on such soils in Pakistan. Several industrial districts of Pakistan were selected for assessment of the risk associated with the ingestion of vegetables grown over sewage-irrigated soils. Both the total and bioaccessible fraction of PHEs (Cd, Co, Cr, Ni, and Pb) and DMs (Fe, Cu, Mn, Zn, Ca, Mg, and I) in soils and vegetable samples were measured. The concentrations of these PHEs and DMs in sewage-irrigated and control soils were below published upper threshold limits. However, compared to control soils, sewage irrigation over the years decreased soil pH (7.7 vs 8.1) and enhanced dissolved organic carbon (1.8 vs 0.8 %), which could enhance the phyto-availability of PHEs and DMs to crops. Of the PHEs and DMs, the highest transfer factor (soil to plant) was noted for Cd and Ca, respectively. Concentrations of PHEs in most of the sewage-irrigated vegetables were below the published upper threshold limits, except for Cd in the fruiting portion of eggplant and bell pepper (0.06–0.08 mg/kg Cd, dry weight) at three locations in Gujarat and Kasur districts. The bioaccessible fraction of PHEs can reduce the context of dietary intake measurements compared to total concentrations, but differences between both measurements were not significant for Cd. Since the soils of the sampled districts are not overly contaminated compared to control sites, vegetables grown over sewage-irrigated soils would provide an opportunity to harvest mineral-rich vegetables potentially providing consumers 62, 60, 12, 104, and 63 % higher dietary intake of Cu, Mn, Zn, Ca, and Mg, respectively. Based on Fe and vanadium correlations in vegetables, it is inferred that a significant proportion of total dietary Fe intake could be contributed by soil particles adhered to the consumable portion of vegetables. Faecal sterol ratios were used to identify and distinguish the source of faecal contamination in soils from Gujranwala, Gujarat, and Lahore districts, confirming the presence of human-derived sewage biomarkers at different stages of environmental alteration. A strong correlation of some metals with soil organic matter concentration was observed, but none with sewage biomarkers.  相似文献   

16.
This study investigates the occurrence and spatial distribution of potentially toxic elements (PTEs) (Hg, Cd, Cu, Mo, Pb, Zn, Ni, Co, Cr, Al, Fe, Mn, V and Sb) in 67 road dust samples collected from urban industrial areas in Ahvaz megacity, southwest of Iran. Geochemical methods, multivariate statistics, geostatistics and health risk assessment model were adopted to study the spatial pollution pattern and to identify the priority pollutants, regions of concern and sources of the studied PTEs. Also, receptor positive matrix factorization model was employed to assess pollution sources. Compared to the local background, the median enrichment factor values revealed the following order: Sb > Pb > Hg > Zn > Cu > V > Fe > Mo > Cd > Mn > Cr ≈ Co ≈ Al ≈ Ni. Statistical results show that a significant difference exists between concentrations of Mo, Cu, Pb, Zn, Fe, Sb, V and Hg in different regions (univariate analysis, Kruskal–Wallis test p < 0.05), indicating the existence of highly contaminated spots. Integrated source identification coupled with positive matrix factorization model revealed that traffic-related emissions (43.5%) and steel industries (26.4%) were first two sources of PTEs in road dust, followed by natural sources (22.6%) and pipe and oil processing companies (7.5%). The arithmetic mean of pollution load index (PLI) values for high traffic sector (1.92) is greater than industrial (1.80) and residential areas (1.25). Also, the results show that ecological risk values for Hg and Pb in 41.8 and 9% of total dust samples are higher than 80, indicating their considerable or higher potential ecological risk. The health risk assessment model showed that ingestion of dust particles contributed more than 83% of the overall non-carcinogenic risk. For both residential and industrial scenarios, Hg and Pb had the highest risk values, whereas Mo has the lowest value.  相似文献   

17.

This study investigated the content, distribution, and contamination levels of toxic metals (Cd, Cr, Cu, Pb, and Zn) in street dust in Lanzhou, an industrial city in Northwest China. Meanwhile, the risk these metals posed to the urban ecosystem and human health was also evaluated using the potential ecological risk index and human exposure model. Results showed that concentrations of these metals in the dust are higher than the background value of local soil, with Cu having the highest levels. The districts of Anning and Xigu had the most extreme levels of contamination, while Chengguan and Qilihe districts were lightly contaminated, which can be partly attributed to human activities and traffic densities. In comparison with the concentrations of selected metals in other cities, the concentrations of heavy metals in Lanzhou were generally at moderate or low levels. Heavy metal concentration increased with decreasing dust particle size. The pollution indices of Cr, Cd, Cu, Pb, and Zn were in the range of 0.289–2.09, 0.332–2.15, 1.38–6.21, 0.358–2.59, and 0.560–1.83 with a mean of 1.37, 1.49, 3.18, 1.48, and 0.897, respectively. The geo-accumulation index (I geo) suggested that Zn in street dust was of geologic origin, while Cd, Cr, Pb, and Cu were significantly impacted by anthropogenic sources. The comprehensive pollution index showed that urban dust poses a high potential ecological risk in Lanzhou. Non-carcinogenic and carcinogenic effects due to exposure to urban street dust were assessed for both children and adults. For non-carcinogenic effects, ingestion appeared to be the main route of exposure to dust particles and thus posed a higher health risk to both children and adults for all metals, followed by dermal contact. Hazard index values for all studied metals were lower than the safe level of 1, and Cr exhibited the highest risk value (0.249) for children, suggesting that the overall risk from exposure to multiple metals in dust is low. The carcinogenic risk for Cd and Cr was all below the acceptable level (< 10−6).

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18.
Tailings, agricultural soils, vegetables and groundwater samples were collected from abandoned metal mines (Duckum, Dongil, Dongjung, Myoungbong and Songchun mines) in Korea. Total concentrations of arsenic (As) and heavy metals (Cd, Cu, Pb and Zn) were analyzed to investigate the contamination level. Several digestion methods (Toxicity characteristics leaching procedure (TCLP), synthetic precipitation leaching procedure (SPLP), 0.1 N/1 N HCl) and sequential extraction analysis for mine tailings were conducted to examine the potential leachability of As and heavy metals from the tailings. The order of urgent remediation for the studied mines based on the risk assessment and remedial goals was suggested. The Songchun mine tailings were most severely contaminated by As and heavy metals. Total concentrations of As and Pb in the tailings were 38,600–58,700 mg/kg (av. 47,400 mg/kg) and 11,800–16,800 mg/kg (av. 14,600 mg/kg), respectively. Agricultural soils having high As concentrations were found at the all mines. Average concentrations of Cd in the vegetables exceeded the normal value at all mines areas, while As only at the Dongjung, Myoungbong, and Songchun mine area. One groundwater sample each from the Dongil and Myoungbong mines, and 4 groundwater samples from the Songchun mine had values above 10 μg/L of As concentration. The TCLP method revealed that only Pb in the Songchun tailings, 6.49 mg/L, exceeded the regulatory level (5 mg/L). Employing the 1-N HCl digestion method, the concentration of As in the Songchun mine tailings, 4,250 mg/kg, was up to 3,000 times higher than its Korean countermeasure standard. Results from the sequential extraction of As in the tailings showed that the easily releasable fraction in the Myoungbong and Songchun mine tailings was more than 30% and the residual fraction was less than 40%. Based on results showing the exposure health risk employing the hazard quotient and cancer risk of As, Cd and Zn, the Dongil mine needs the most urgent remedial action. The concentration reduction factor (CRF) of As in both soil and groundwater follows the order: Songchun>Dongjung>Dongil>Myoungbong>Duckum mine.  相似文献   

19.

Environmental geochemistry classifies elements into essential, non-essential and toxic elements in relationship to human health. To assess the environmental impact of mining at Datoko-Shega area, the distributions and concentrations of trace elements in stream sediments and soil samples were carried out. X-ray fluorescence analytical technique was used to measure the major and trace element concentrations in sediments and modified fire assay absorption spectrometry in soils. The results showed general depletion of major elements except titanium oxide (TiO2) compared to the average crustal concentrations. The retention of TiO2 at the near surface environment probably was due to the intense tropical weathering accompanied by the removal of fine sediments and soil fractions during the harmattan season by the dry north-east trade winds and sheet wash deposits formed after flash floods. The results also showed extreme contamination of selenium (Se), cadmium (Cd) and mercury (Hg), plus strong contaminations of arsenic (As) and chromium (Cr) in addition to moderate contamination of lead (Pb) in the trace element samples relative to crustal averages in the upper continental crust. However Hg, Pb and Cd concentrations tend to be high around the artisanal workings. It was recognised from the analysis of the results that the artisanal mining activity harnessed and introduces some potentially toxic elements such as Hg, Cd and Pb mostly in the artisan mine sites. But the interpretation of the trace element data thus invalidates the elevation of As concentrations to be from the mine operations. It consequently noticed As values in the mine-impacted areas to be similar or sometimes lower than As values in areas outside the mine sites from the stream sediment results.

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20.
Due to rapid urbanization and the implementation of ecological civilization construction in China, many industrial factories have been closed or relocated. Therefore, numbers of contaminated sites were generated with contaminated soils which may pose a risk to receptors living nearby. This study presented a spatial health risk assessment and hierarchical risk management policy making for mercury (Hg) in soils from a typical contaminated site in the Hunan Province, central China. Compared with the second class value (0.3 mg/kg) of the Chinese Environmental Quality Standard for Soils, the mean concentrations of Hg in the three soil depths exceeded the second class value. The non-carcinogenic risk of Hg probably posed adverse health effects in 41, 30 and 36 % of the surface soil, the moderate soil and subsoil, respectively, under a sensitive land scenario. The non-carcinogenic risk temporarily posed no adverse health effects in most areas under an insensitive land scenario except for the area around sampling site S29. Spatially, the central, southwest and northeast parts of the contaminated land under a sensitive land scenario should be regarded as the priority regions. For non-carcinogenic effects, the exposure pathways that resulted in the higher levels of exposure risk were ingestion and inhalation of vapors, followed by dermal contact and inhalation of particles. A risk-based integrated risk management policy including the hierarchical risk control values for different soil depths and the calculated remediation earthwork was proposed with consideration of the cost-benefit effect for the related decision-makers.  相似文献   

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