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1.

Trace metal element contamination in mining areas is always a huge environmental challenge for the global mining industry. In this study, an abandoned sphalerite mine near the Yanshan Mountains was selected as subject to evaluate the soil and water contamination caused by small-scale mining. The results show that (1) Pearson correlation matrix and principal component analysis (PCA) results reveal that Zn, Cu, Cd, and Pb were greatly affected by the operation of mines, especially mineral tailings. The contents of trace metal elements decrease with the increase of the distance from the mining area. Zinc, Pb, and Cd were discovered in almost all soil samples, and Zn accounted for about 80% of pollution of the topsoil. (2) The trace element pollution levels in the topsoil of the three villages were ranked as follows: Cd?>?Cu?>?Pb~Zn. The potential ecological risk of farmland around the mine ranges from lower to higher, with Cd being the most harmful. (3) Human health risk assessment results show that trace elements in the mining area pose obvious non-carcinogenic health risks to children while the risks to adults are not equally obvious. The carcinogenic risk of Cd and Cr is within a safe range and does not pose an obvious cancer risk to the population.

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2.
This study identifies the natural background, anthropogenic background and distribution of contamination caused by heavy metal pollutants in soil in Chunghua County of central Taiwan by using a finite mixture distribution model (FMDM). The probabilities of contaminated area distribution are mapped using single-variable indicator kriging and multiple-variable indicator kriging (MVIK) with the FMDM cut-off values and regulation thresholds for heavy metals. FMDM results indicate that Cr, Cu, Ni and Zn can be individually fitted by a mixture model representing the background and contamination distributions of the four metals in soil. The FMDM cut-off values for contamination caused by the metals are close to the regulation thresholds, except for the cut-off value of Zn. The receiver operating characteristic (ROC) curve validates that indicator kriging and MVIK with FMDM cut-off values can reliably delineate heavy metals contamination, particularly for areas lacking background information and high heavy metal concentrations in soil.  相似文献   

3.
To investigate the extent of Hg contamination due to artisanal Zn smelting activities in Weining County, northwestern Guizhou, China, total Hg and methyl mercury (MeHg) concentrations in soil and surface water were determined. Samples of corn plants growing in the study area were also collected for total Hg analysis. A high geometric mean Hg emission factor of 75gHgt(-1)Zn was estimated and significantly elevated total gaseous mercury (TGM) concentrations were found in the atmosphere adjacent to the Zn smelting sites, ranging from 30 to 3814ngm(-3). Total Hg and MeHg concentrations in topsoil samples ranged from 62 to 355microgkg(-1) and from 0.20 to 1.1microgkg(-1), respectively. Total Hg Concentrations in corn plant tissues increased in the order of grains相似文献   

4.
Lee CC  Guo YL  Kuei CH  Chang HY  Hsu JF  Wang ST  Liao PC 《Chemosphere》2006,65(3):436-448
A pentachlorophenol (PCP) manufacturing plant in southern Taiwan discontinued production in 1989. The site of the abandoned plant was heavily contaminated by PCDD/PCDFs, impurities formed in the PCP production process. Serum samples collected from 27 residents living near the deserted plant were evaluated to determine whether this contamination had associated serum levels of PCDD/PCDFs in local residents. The average level of 17 tested congeners ranged from 556 to 5240 pg/g lipid (mean, 1670 pg/g lipid). The corresponding 2,3,7,8-TCDD toxicity equivalent quotient values calculated by international toxicity equivalent factors (I-TEFs) and those recommended by WHO (WHO-TEFs) were 47.2 pg I-TEQ/g lipid and 53.4 pg WHO-TEQ/g lipid, respectively. Levels in other parts of Taiwan typically range from 15 to 20 pg WHO-TEQ/g lipid; therefore, it is likely that the heavily contaminated plant site caused these unusually high serum levels. The average PCDD/PCDF levels of 29 fish-tissue and nine soil samples collected from the sea reservoir surrounding the abandoned PCP plant were also abnormally high: 8630 pg/g lipid (985 pg WHO-TEQ/g lipid) and 606000 pg/g-sample (922 pg WHO-TEQ/g-sample), respectively. Factor analysis indicated that the congener pattern of human serum samples collected from residents living near the abandoned PCP plant different from samples collected from other areas in Taiwan without known PCDD/PCDF pollution. Similar results were observed for the fish tissue and soil samples. The current study may have discovered a "hot spot" for elevated dioxin human exposure in Taiwan. The preliminary finding has raised a public health concern in the inspected area and requires further investigations to clarify the nature of the contamination and potential impact on the local environment and human health.  相似文献   

5.
Young Populus tremula, Salix viminalis, Betula pendula and Picea abies trees were grown together in large open-top chambers. The treatments were: without or with (Cu/Zn/Cd/Pb=640/3000/10/90 mg kg-1) metal contamination in the topsoil, irrigation pH 3.5 or 5.5, and acidic or calcareous subsoil. Growth, metal allocation to foliage and wood, as well as leaf gas exchange were measured. Biomass was reduced in P. tremula and B. pendula by the metal-contaminated topsoil relative to uncontaminated topsoil, whereas in P. tremula photosynthesis and transpiration were decreased. These effects were related to the elevated foliar Zn accumulation in P. tremula. S. viminalis showed a significant reduction in growth and an increased Zn and Cd accumulation on acidic vs. calcareous subsoil. Acidic irrigation produced only a few significant effects. P. abies showed the lowest metal uptake and no growth response to metal contamination.  相似文献   

6.
The Qinling panda subspecies (Ailuropoda melanoleuca qinlingensis) is highly endangered with fewer than 350 individuals inhabiting the Qinling Mountains. Previous studies have indicated that giant pandas are exposed to heavy metals, and a possible source is vehicle emission. The concentrations of Cu, Zn, Mn, Pb, Cr, Ni, Cd, Hg, and As in soil samples collected from sites along a major highway bisecting the panda’s habitat were analyzed to investigate whether the highway was an important source of metal contamination. There were 11 sites along a 30-km stretch of the 108th National Highway, and at each site, soil samples were taken at four distances from the highway (0, 50, 100, and 300 m) and at three soil depths (0, 5, 10 cm). Concentrations of all metals except As exceeded background levels, and concentrations of Cu, Zn, Mn, Pb, and Cd decreased significantly with increasing distance from the highway. Geo-accumulation index indicated that topsoil next to the highway was moderately contaminated with Pb and Zn, whereas topsoil up to 300 m away from the highway was extremely contaminated with Cd. The potential ecological risk index demonstrated that this area was in a high degree of ecological hazards, which were also due to serious Cd contamination. And, the hazard quotient indicated that Cd, Pb, and Mn especially Cd could pose the health risk to giant pandas. Multivariate analyses demonstrated that the highway was the main source of Cd, Pb, and Zn and also put some influence on Mn. The study has confirmed that traffic does contaminate roadside soils and poses a potential threat to the health of pandas. This should not be ignored when the conservation and management of pandas is considered.  相似文献   

7.
Infiltration basins are frequently used for stormwater drainage. Because stormwater is polluted in highly toxic compounds, assessment of pollution retention by infiltration basins is necessary. Indeed, if basins are not effective in trapping pollution, deep soil and groundwater may be contaminated. This study's objective is to investigate soil pollution in infiltration basins: spatial distribution of soil pollution, optimisation of the number of soil samples and a contamination indicator are presented. It is part of a global project on long-term impact of stormwater infiltration on groundwater. Soil sampling was done on a basin in suburban Lyon (France). Samples were collected at different depths and analysed for nutrients, heavy metals, hydrocarbons and grain size. Pollutant concentrations decrease rapidly with depth while pH, mineralisation and grain size increase. Sustainable metal concentrations are reached at a 30-cm depth, even after 14 years of operation; hydrocarbon pollution is deeper. Principal component analysis shows how pollutants affect each level. The topsoil is different from other levels. Three specifically located points are enough to estimate the mass of pollution trapped by the basin with a 26% error. The proposed contamination indicator is calculated using either average level concentrations or maximum level concentrations. In both cases, the topsoil layer appears polluted but evaluation of lower levels is dependent on the choice of input concentrations.  相似文献   

8.
This study aimed to analyze the contamination potential associated with the reactive transport of nitrate-N and ammonium-N in the Choushui River alluvial fan, Taiwan and to evaluate a risk region in developing a groundwater protection policy in 2021. In this area, an aquifer redox sequence provided a good understanding of the spatial distributions of nitrate-N and ammonium-N and of aerobic and anaerobic environments. Equiprobable hydraulic conductivity (K) fields reproduced by geostatistical methods characterized the spatial uncertainty of contaminant transport in the heterogeneous aquifer. Nitrogen contamination potential fronts for high and low threshold concentrations based on a 95% risk probability were used to assess different levels of risk. The simulated result reveals that the spatial uncertainty of highly heterogeneous K fields governs the contamination potential assessment of the nitrogen compounds along the regional flow directions. The contamination potential of nitrate-N is more uncertain than that for ammonium-N. The high nitrate-N concentrations (> or =3 mg/L) are prevalent in the aerobic environment. The low concentration nitrate-N plumes (0.5-3 mg/L) gradually migrate to the mid-fan area and to a maximum distance of 15 km from the aerobic region. The nitrate-N plumes pose a potential human health risk in the aerobic and anaerobic environments. The ammonium-N plumes remain stably confined to the distal-fan and partial mid-fan areas.  相似文献   

9.
This study investigated the indoor air quality (IAQ) conditions of carbon dioxide (CO2), carbon monoxide (CO), ozone (O3), formaldehyde (HCHO), total volatile organic compounds (TVOCs), and bio-aerosols (bacteria and fungi) in a respiratory type of medical facility in Chia-Yi County in southern Taiwan. Among those IAQ conditions, the concentrations of CO, O3, and HCHO exceeded the regulation values of the Taiwan Environmental Protection Administration (EPA) mostly in the morning. The concentrations of bacteria and fungi did not exceed the regulation values but still posed potential health and environment problems for workers, patients, and visitors. Therefore, self-made silver-coated zeolite (AgZ) was used as a filter material in air cleaners to remove bio-aerosols in the respiratory care ward (RCW), and the removals were still effective after 120 hr. The cumulative bio-aerosol removals for bacteria and fungi were 900 and 1,088 colony-forming units (CFU) g?1 after 24 hr and were above 3,100 and 2,700 CFU g?1 after 120 hr. From the research results, it is suggested that AgZ filtering could be used as a feasible engineering measure for hospitals to control their bacteria and fungi parameters in IAQ management. Hospitals should maintain their environmental management and monitoring programs and use different engineering measures to improve different IAQ parameters.

Implications: This study investigated the IAQ conditions in the field at a hospital in Chia-Yi County in southern Taiwan. Although concentrations of most parameters were still within the regulation values, the concentrations of CO, O3, and HCHO were partially exceeded. We propose a method using an air cleaner with silver-coated zeolite (AgZ) as a possible engineering measure, and there were effective reductions of bacteria and fungi to lower levels with antibacterial effects after 120 hr. Furthermore, this study implies that hospitals should continuously maintain environmental monitoring programs and adopt optimal engineering measures for different needs.  相似文献   

10.
Urban soil is an important component of urban ecosystems. This study focuses on heavy metal contamination in soils of Wien (Austria) and results are compared to those for a few large European cities. We analysed the elemental contents of 96 samples of topsoil from urban, suburban and rural areas in Wien along a dynamic (floodplain forest) and a stable (oak–hornbeam forest) urbanization gradient. The following elements were quantified using ICP-OES technique: Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Pb, P, S and Zn. For heavy metals PI (pollution index) values were used to assess the level of pollution. The PI values indicated high level of pollution by Pb in the suburban and rural area of stable gradient and in the urban area of dynamic gradient; moderate level of pollution was indicated for Cd in the urban area of stable gradient. The level of pollution was moderate for Co in the suburban and rural area of the stable gradient, and for Cu in suburban area of stable gradient, and urban area of dynamic gradient. The pollution level of Zn was moderate in all areas. Urban soils, especially in urban parks and green areas may have a direct influence on human health. Thus, the elemental analysis of soil samples is one of the best ways to study the effects of urbanization. Our results indicated that the heavy metal contamination was higher in Wien than in a few large European cities.  相似文献   

11.
Laabs V  Amelung W  Pinto A  Altstaedt A  Zech W 《Chemosphere》2000,41(9):1441-1449
Pesticide pollution of ground and surface water is of growing concern in tropical countries. The objective of this pilot study was to evaluate the leaching potential of eight pesticides in a Brazilian Oxisol. In a field experiment near Cuiabá, Mato Grosso, atrazine, chlorpyrifos, lambda-cyhalothrin, endosulfane alpha, metolachlor, monocrotofos, simazine, and trifluraline were applied onto a Typic Haplustox. Dissipation in the topsoil, mobility within the soil profile and leaching of pesticides were studied for a period of 28 days after application. The dissipation half-life of pesticides in the topsoil ranged from 0.9 to 14 d for trifluraline and metolachlor, respectively. Dissipation curves were described by exponential functions for polar pesticides (atrazine, metolachlor, monocrotofos, simazine) and bi-exponential ones for apolar substances (chlorpyrifos, lambda-cyhalothrin, endosulfane alpha, trifluraline). Atrazine, simazine and metolachlor were moderately leached beyond 15 cm soil depth, whereas all other compounds remained within the top 15 cm of the soil. In lysimeter percolates (at 35 cm soil depth), 0.8-2.0% of the applied amounts of atrazine, simazine, and metolachlor were measured within 28 days after application. Of the other compounds less than 0.03% of the applied amounts was detected in the soil water percolates. The relative contamination potentials of pesticides, according to the lysimeter study, were ranked as follows: metolachlor > atrazine = simazine > monocrotofos > endsulfane alpha > chlorpyrifos > trifluraline > lambda-cyhalothrin. This order of the pesticides was also achieved by ranking them according to their effective sorption coefficient Ke, which is the ratio of Koc to field-dissipation half-life.  相似文献   

12.
The San Jacinto River (SJR) waste pits that lie just under the 1–10 overpass in eastern Harris County east of Houston, Texas, USA, were created in the 1960s as dumping grounds for paper mill waste. The deposition of this waste led to accumulation of highly toxic polychlorinated dibenzo-p-dioxins and dibenzofurans (PCCDDs/PCDFs) over the course of several decades. After abandonment, the waste material eventually became submerged under the waters of the SJR, resulting in widespread environmental contamination that currently constitutes a significant health concern for eastern Harris County communities. The original waste pits were rediscovered in 2005, and the San Jacinto waste site is now a designated EPA superfund site. The objective of this review then is to discuss the history and current state of containment around the San Jacinto waste pits and analyze spatial and temporal trends in the PCDD/PCDF deposition through the SJR system from the data available. We will discuss the current exposure and health risks represented by the Superfund site and the SJR system itself, as well as the discovery of liver, kidney, brain (glioma), and retinoblastoma cancer clusters in eastern Harris County across multiple census tracts that border the Superfund site. We will also cover the two primary management options, containment versus removal of the waste from the Superfund and provide recommendations for increased monitoring of existing concentrations of polychlorinated waste in the SJR and its nearby associated communities.  相似文献   

13.
Bioremediation is the use of living organisms, primarily microorganisms, to degrade environmental contaminants into less toxic forms. Nine biobeds (ground cavity filled with a mixture of composted organic matter, topsoil, and a surface grass) were established at Kentucky State University research farm (Franklin County, KY) to study the impact of this practice on reducing surface runoff water contamination by residues of dimethazone and trifluralin herbicides arising from an agricultural field. Biobed (biofilter) systems were installed at the bottom of the slope of specially designed runoff plots to examine herbicides retention and degradation before entering streams and rivers. In addition to biobed systems, three soil management practices: municipal sewage sludge (SS), SS mixed with yard waste compost (SS + YW), and no-mulch rototilled bare soil (NM used for comparison purposes) were used to monitor the impact of soil amendments on herbicide residues in soil following natural rainfall events. Organic amendments increased soil organic matter content and herbicide residues retained in soil following rainfall events. Biobeds installed in NM soil reduced dimethazone and trifluralin by 84 and 82%, respectively in runoff water that would have been transported down the land slope of agricultural fields and contaminated natural water resources. Biobeds installed in SS and SS+YW treatments reduced dimethazone by 65 and 46% and trifluralin by 52 and 79%, respectively. These findings indicated that biobeds are effective for treating dimethazone and trifluralin residues in runoff water.  相似文献   

14.
Samples of moss (Scleropodium purum or, in its absence, Hypnum cupressiforme) and of topsoil (0-5 cm) were collected in the spring of 1995, from 75 sites distributed throughout Galicia (northwest Spain) in order to compare the potential usefulness of each in evaluating the atmospheric deposition of contaminants. Analysis was made of the total content of various metals in the moss and of different soil metal fractions (including total metal content, labile metals and metals bound to organic material). We found that the labile fraction most closely resembled the metal content of the moss. Calculation of enrichment factors allowed us to show that the soil was not, except in the case of Cr, the main source of contamination in the moss. By comparing contamination factors of metals in moss and soil fraction samples we found that moss samples were more useful for evaluating the degree of contamination at different sites.  相似文献   

15.
Thirty-two topsoil samples were collected to analyze the residue levels of organochlorine pesticides (OCPs) in topsoil of arid and semiarid areas of northwest China in 2011. Results showed that DDTs were the dominant contaminants with a mean concentration of 12.52 ng/g. The spatial distribution characteristics indicated that α-hexachlorocyclohexanes (HCHs) were mainly used in rural sites, whereas hexachlorobenzene (HCB) and endosulfan were detected mostly in urban areas. DDTs, heptachlor, and chlordane were found almost equally in both urban and rural areas. Source identification revealed that the current levels of HCHs in soils were attributable to the residues from their historical use and fresh usage of lindane (γ-HCH). DDTs were mainly from historical use and fresh usage of dicofol, and HCB was emitted from the chemical industry. It was also found that the current soil levels of heptachlor were mainly from its historical usage, endosulfan from fresh input, and chlordane from long-range atmospheric transport, respectively. The noncarcinogenic health risk assessment with a model was also conducted using USEPA standards for adults and children. Results indicated that health risk under nondietary exposure to OCPs decreased in the sequence of ΣDDT?>?ΣHCH?>?HCB?>?Σheptachlor?>?Σendosulfan?>?Σchlordane. According to the reference dose from the USEPA, the health risk under nondietary exposure to OCPs in the soil samples was at a relatively safe level.  相似文献   

16.
Many sites of contamination due to inappropriate disposal of hazardous materials or wastes have been found. These sites have the potential of damaging the environment and human health and thus need to be evaluated as to whether and what actions should be initiated. In the decision on whether a contaminated site should be subject to management, the knowledge concerning important parameters that would influence the decision will be beneficial to planning of data collection to support the decision. This paper presents a case study of contaminated site located in northern Taiwan, where the groundwater is contaminated by chlorinated hydrocarbons including trichloroethylene (TCE) and tetrachloroethylene (PCE). A site-specific multimedia risk assessment is performed to estimate the total risk resulting from the contamination. In addition, Monte Carlo simulation, rank correlation coefficients, and decision criteria are combined to develop a methodology for assessing the important of parameters in terms of their influence on the decision. It is found that TCE concentration, vegetable yield, deposition interception fraction of vegetables, and plant surface loss constant, are the four parameters important to the decision-making of the case problem.  相似文献   

17.
Human health risks associated with the consumption of metal-contaminated fish over extended periods have become a concern particularly in Taiwan, where fish is consumed on a large scale. This study applied the interaction-based hazard index (HI) to assess the mixture health risks for fishers and non-fishers who consume the arsenic (As), copper (Cu), and zinc (Zn) contaminated milkfish from As-contaminated coastal areas in Taiwan, taking into account joint toxic actions and potential toxic interactions. We showed that the interactions of As–Zn and Cu–Zn were antagonistic, whereas As–Cu interaction was additive. We found that HI estimates without interactions considered were 1.3–1.6 times higher than interactive HIs. Probability distributions of HI estimates for non-fishers were less than 1, whereas all 97.5%-tile HI estimates for fishers were >1. Analytical results revealed that the level of inorganic As in milkfish was the main contributor to HIs, indicating a health risk posed to consumers of fish farmed in As-contaminated areas. However, we found that Zn supplementation could significantly decrease As-induced risk of hematological effect by activating a Zn-dependent enzyme. In order to improve the accuracy of health risk due to exposure to multiple metals, further toxicological data, regular environmental monitoring, dietary survey, and refinement approaches for interactive risk assessment are warranted.  相似文献   

18.
Li HB  Yu S  Li GL  Deng H 《Chemosphere》2012,88(10):1161-1169
Lead contamination becomes of importance to urban resident health worldwide, especially for child health and growth. Undisturbed lake sediment cores are increasingly employed as a useful tool to backdate environmental contamination history. Five intact sediment cores collected from lakes in five urban parks were dated using (210)Pb and analyzed for total Pb content and isotope ratio to reconstruct the Pb contamination history over the last century in Shanghai, China. Total Pb content in the sediment cores increased by about 2- to 3-fold since 1900s. The profile of Pb flux in each sediment core revealed a remarkable increase of Pb contamination in Shanghai over the past century, especially in the latest three decades when China was experiencing a rapid economic and industrial development. Significant correlations were found between Pb fluxes in sediment cores and Pb emission from coal combustion in Shanghai. Coal combustion emission dominated anthropogenic Pb sources during the past century contributing from 52% to 69% of total Pb in cores, estimated by a three-end member model of Pb isotope ratios. Leaded gasoline emission generally contributed <30% of total Pb, which was banned by 1997 in the Shanghai region. Our results implicate that coal combustion-based energy consumption should be replaced, or at least partially replaced, to reduce health risks of Pb contamination in Shanghai.  相似文献   

19.
Spatial distribution of mercury in topsoil from five regions of China   总被引:1,自引:0,他引:1  
The concentrations and distributions of mercury (Hg) in topsoil from four provinces and one municipality in China were investigated. A total of 1,254 samples were collected and analyzed. The average concentrations of Hg were 0.064 mg kg?1 for Liaoning Province, 0.100 mg kg?1 for Jiangsu Province, 0.110 mg kg?1 for Zhejiang Province, 0.154 mg kg?1 for Sichuan Province, and 0.098 mg kg?1 for Chongqing Municipality. Although differences were found among the ranges of Hg concentrations, the average values for each region were similar with other published data. The concentrations of Hg in topsoil varied largely upon the sampling locations. More than 80 % of the soil samples from Liaoning Province, Jiangsu Province, Zhejiang Province, and Chongqing Municipality, were ranked Grade I by the China Environmental Quality Standard for Soils, which can be considered as not contaminated by Hg. The concentrations of Hg in 0.3–0.4 % of soils collected from Jiangsu Province, Zhejiang Province and Chongqing Municipality exceeded the limitation for Grade III, indicating the contamination of Hg in these sites. The sources and potential risks of Hg in these sites should be brought to attention and further investigated.  相似文献   

20.
Abstract

A huge amount of volatile organic compounds (VOCs) is produced and emitted with waste gases from semiconductor manufacturing processes, such as cleaning, etching, and developing. VOC emissions from semiconductor factories located at Science-Based Industrial Park, Hsin-chu, Taiwan, were measured and characterized in this study. A total of nine typical semiconductor fabricators (fabs) were monitored over a 12-month period (October 2000-September 2001). A flame ionization analyzer was employed to measure the VOC emission rate continuously in a real-time fashion. The amount of chemical use was adopted from the data that were reported to the Environmental Protection Bureau in Hsin-chu County as per the regulation of the Taiwan Environmental Protection Administration. The VOC emission factor, defined as the emission rate (kg/month) divided by the amount of chemical use (L/month), was determined to be 0.038 ± 0.016 kg/L. A linear regression equation is proposed to fit the data with the correlation coefficient (R2) = 0.863. The emission profiles of VOCs, which were drawn using the gas chromatograph/mass spectrometer analysis method, show that isopropyl alcohol is the dominant compound in most of the fabs.  相似文献   

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