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1.
Characterizing water quality and identifying potential pollution sources could greatly improve our knowledge about human impacts on the river ecosystem. In this study, fuzzy comprehensive assessment (FCA), pollution index (PI), principal component analysis (PCA), and absolute principal component score–multiple linear regression (APCS–MLR) were combined to obtain a deeper understanding of temporal–spatial characterization and sources of water pollution with a case study of the Jinjiang River, China. Measurement data were obtained with 17 water quality variables from 20 sampling sites in the December 2010 (withered water period) and June 2011 (high flow period). FCA and PI were used to comprehensively estimate the water quality variables and compare temporal–spatial variations, respectively. Rotated PCA and receptor model (APCS–MLR) revealed potential pollution sources and their corresponding contributions. Application results showed that comprehensive application of various multivariate methods were effective for water quality assessment and management. In the withered water period, most sampling sites were assessed as low or moderate pollution with characteristics pollutants of permanganate index and total nitrogen (TN), whereas 90 % sites were classified as high pollution in the high flow period with higher TN and total phosphorus. Agricultural non-point sources, industrial wastewater discharge, and domestic sewage were identified as major pollution sources. Apportionment results revealed that most variables were complicatedly influenced by industrial wastewater discharge and agricultural activities in withered water period and primarily dominated by agricultural runoff in high flow period.  相似文献   

2.
This study reports source apportionment of polycyclic aromatic hydrocarbons (PAHs) in particulate depositions on vegetation foliages near highway in the urban environment of Lucknow city (India) using the principal components analysis/absolute principal components scores (PCA/APCS) receptor modeling approach. The multivariate method enables identification of major PAHs sources along with their quantitative contributions with respect to individual PAH. The PCA identified three major sources of PAHs viz. combustion, vehicular emissions, and diesel based activities. The PCA/APCS receptor modeling approach revealed that the combustion sources (natural gas, wood, coal/coke, biomass) contributed 19–97% of various PAHs, vehicular emissions 0–70%, diesel based sources 0–81% and other miscellaneous sources 0–20% of different PAHs. The contributions of major pyrolytic and petrogenic sources to the total PAHs were 56 and 42%, respectively. Further, the combustion related sources contribute major fraction of the carcinogenic PAHs in the study area. High correlation coefficient (R 2 > 0.75 for most PAHs) between the measured and predicted concentrations of PAHs suggests for the applicability of the PCA/APCS receptor modeling approach for estimation of source contribution to the PAHs in particulates.  相似文献   

3.
Efficient management of deteriorating water bodies can be achieved by determining the sources of faecal pollution. Resourceful techniques for discrimination of the sources of Escherichia coli in surface water have recently been developed, including the use of river water to facilitate faecal indicator surveillance, identification of sources of faecal contamination and employing relevant management practices to maintain water quality. This study was conducted to employ microbial source tracking (MST) techniques for the determination of the sources of faecal pollution based on a water quality investigation of the physico-chemical characteristics and coliform count point of the Tirumanimuttar River. To accomplish this, an MST library-based antibiotic resistance analysis, serotyping and the genomic tool rep-PCR techniques were applied, and the obtained results were analysed statistically. Among 135 and 70 E. coli isolates present in the library and water samples collected from the river and nearby well water sources, respectively, most showed intrinsic, high or moderate resistance to antibiotics. Isolates from human and pig faecal sources were 92% homologous with the samples from the river, whereas isolates from sewage and dairy cattle showed 89% and 80% homology, respectively. These findings indicated that the Tirumanimuttar River is subjected to stress from anthropogenic activities and runoff contaminated with agricultural and human faecal contamination. The sources of faecal pollution identified in this study may facilitate the monitoring and management of the Tirumanimuttar River.  相似文献   

4.
Ambient air monitoring for suspended particulate matter was carried over a period of one year in some coal mining areas of the Raniganj coalfield. Concentrations of seven elements in suspended particulate matter were determined. The set of data obtained was analysed to determine the sources of trace elements by factor analysis. The data could be interpreted on the basis of five factors. These factors are attributed to various sources of particulate matter by noting the dependence of factors on the elements.  相似文献   

5.
Deterioration of art objects at Salarjung Museum has been noticed such as blackening of white and pink pigments of Indian miniature paintings and other objects like pigments, paints, varnishes, coatings, silver ware, zari works, textiles, which are displayed in museum galleries. The cause of deterioration of the artifacts is attributed to air pollution. The outdoor air pollution levels with respect to suspended particulate matter, sulphur dioxide, oxides of nitrogen, ammonia, aldehydes and oxidants are observed to be high when compared with background environment and ambient air quality standards for sensitive areas. The indoor air quality levels in terms of various parameters including temperature and relative humidity (RH) observed to be more than the threshold limits. The climatic conditions coupled with polluted indoor air are the main causes for the deterioration of art objects. Hence remedial measures are suggested to avoid further deterioration of objects.  相似文献   

6.
通过乌鲁木齐市2013年2月5日至26日一次重污染天气过程中,在6个采样点位进行细颗粒物PM_(2.5)的采集,并对其中的13种重金属(Cu、Sr、Mo、Cd、Pb、V、Cr、Mn、Fe、Co、Ni、As、Hg)含量、Mull污染指数、空间分布以及溯源进行了分析。结果显示:采样期间乌鲁木齐市重金属浓度在0.23~178 ng/m~3之间,浓度水平排序PbMnCrFeAsVCuNiSrCdMoCoHg,其中Cd、Hg、Pb、Cr、As浓度均高于乌鲁木齐市背景值和国内外其他城市水平,且Mull污染指数处于较严重的污染水平;在重金属元素浓度的空间分布上,铁招和南公园点位重金属浓度较高,31中学和市监测站相对较低。  相似文献   

7.
The present study proposed to investigate the atmospheric distribution, sources, and inhalation health risks of polycyclic aromatic hydrocarbons (PAHs) in a tropical megacity (Delhi, India). To this end, 16 US EPA priority PAHs were measured in the inhalable fraction of atmospheric particles (PM10; aerodynamic diameter, ≤10 μm) collected weekly at three residential areas in Delhi from December 2008 to November 2009. Mean annual 24 h PM10 levels at the sites (166.5–192.3 μg m?3) were eight to ten times the WHO limit. Weekday/weekend effects on PM10 and associated PAHs were investigated. Σ16PAH concentrations (sum of 16 PAHs analyzed; overall annual mean, 105.3 ng m?3; overall range, 10.5–511.9 ng m?3) observed were at least an order of magnitude greater than values reported from European and US cities. Spatial variations in PAHs were influenced by nearness to traffic and thermal power plants while seasonal variation trends showed highest concentrations in winter. Associations between Σ16PAHs and various meteorological parameters were investigated. The overall PAH profile was dominated by combustion-derived large-ring species (85–87 %) that were essentially local in origin. Carcinogenic PAHs contributed 58–62 % to Σ16PAH loads at the sites. Molecular diagnostic ratios were used for preliminary assessment of PAH sources. Principal component analysis coupled with multiple linear regression-identified vehicular emissions as the predominant source (62–83 %), followed by coal combustion (18–19 %), residential fuel use (19 %), and industrial emissions (16 %). Spatio-temporal variations and time-evolution of source contributions were studied. Inhalation cancer risk assessment showed that a maximum of 39,780 excess cancer cases might occur due to lifetime inhalation exposure to the analyzed PAH concentrations.  相似文献   

8.
Hussainsagar Lake in the heart of Hyderabad City (India) receives toxic substances through five streams draining from a catchment area of 245 km2. Of particular interest are heavy metals received from urban runoff as well as municipal sewage and industrial effluents. Heavy metals entering the lake get adsorbed onto the suspended sediments, which eventually settle down in the bottom of the lake. In this study, fractionation of metal ions has been studied on the bed sediments of Hussainsagar Lake in order to determine the ecotoxic potential of metal ions. Comparison of sediments with average shale values indicated anthropogenic enrichment with copper, nickel, lead, cadmium, and zinc. The risk assessment code as applied to the present study reveals that 10–17% of manganese, 10–18% of nickel, 14–24% of chromium, 10–19% of lead, 21–30% of cadmium, and 18–28% of zinc exist in exchangeable fraction and, therefore, comes under medium risk category and may enter into food chain. The association of these metals with the exchangeable fraction may cause deleterious effects to aquatic life. The present database will help in formulating guidelines for carrying out dredging operations under restoration programs in the Hussainsagar Lake.  相似文献   

9.
Geochemical study of groundwater from a structurally deformed granitic terrain near Hyderabad (India) was carried out to understand and evaluate the hydrogeochemical processes and quality of groundwater. Several trace elements (Fe, Mn, Be, Al, V, Cr, Co, Ni, Cu, Zn, As, Sr, Mo, Cd, Sb, Ba, Pb, U) along with major ions and minor elements were precisely estimated in shallow and drilled wells to know the suitability of water for drinking and irrigation purposes. Analytical data shows that pH and major ion chemistry in dug wells and bore wells do not vary significantly, while some trace elements (Fe, Mn, Al, Be, Co, Pb, U and Zn) vary in dug wells and bore wells, which can be attributed to differential mineral weathering and dissolution/precipitation reactions along fractures/joints. Although the water is not potable, it was found to be suitable for irrigation with little danger in the development of harmful level of exchangeable sodium. It is inferred that the chemical composition of the groundwater in this region is likely to have its origin from silicate weathering reactions and dissolution/precipitation processes supported by rainfall and groundwater flow.  相似文献   

10.
Studies on quantitative soil contamination due to heavy metals were carried out in Katedan Industrial Development Area (KIDA), south of Hyderabad, Andhra Pradesh, India under the Indo-Norwegian Institutional Cooperation Programme. The study area falls under a semi-arid type of climate and consists of granites and pegmatite of igneous origin belonging to the Archaean age. There are about 300 industries dealing with dyeing, edible oil production, battery manufacturing, metal plating, chemicals, etc. Most of the industries discharge their untreated effluents either on open land or into ditches. Solid waste from industries is randomly dumped along roads and open grounds. Soil samples were collected throughout the industrial area and from downstream residential areas and were analysed by X-ray Fluorescence Spectrometer for fourteen trace metals and ten major oxides. The analytical data shows very high concentrations of lead, chromium, nickel, zinc, arsenic and cadmium through out the industrial area. The random dumping of hazardous waste in the industrial area could be the main cause of the soil contamination spreading by rainwater and wind. In the residential areas the local dumping is expected to be the main source as it is difficult to foresee that rain and wind can transport the contaminants from the industrial area. If emission to air by the smokestacks is significant, this may contribute to considerable spreading of contaminants like As, Cd and Pb throughout the area. A comparison of the results with the Canadian Soil Quality Guidelines (SQGL) show that most of the industrial area is heavily contaminated by As, Pb and Zn and local areas by Cr, Cu and Ni. The residential area is also contaminated by As and some small areas by Cr, Cu, Pb and Zn. The Cd contamination is detected over large area but it is not exceeding the SQGL value. Natural background values of As and Cr exceed the SQGL values and contribute significantly to the contamination in the residential area. However, the availability is considerably less than anthropogenic contaminants and must therefore be assessed differently. The pre- and post-monsoon sampling over two hydrological cycles in 2002 and 2003 indicate that the As, Cd and Pb contaminants are more mobile and may expect to reach the groundwater. The other contaminants seem to be much more stable. The contamination is especially serious in the industrial area as it is housing a large permanent residing population. The study not only aims at determining the natural background levels of trace elements as a guide for future pollution monitoring but also focuses on the pollution vulnerability of the watershed. A plan of action for remediation is recommended.  相似文献   

11.
Source apportionment study was performed, applying principal component analysis to the results of 221 chemical analyses of PM10 and PM2.5 samples collected daily from the industrial (but low traffic) Spanish town of Puertollano over a 14-month period during 2004-2005. Results reveal compositional variations attributable to different mixtures of natural and anthropogenic materials, mainly soil and rock dust (crustal), marine salt (only in PM10), petrochemical refinery emissions, and particles attributed to the combustion of local coal, which is unusually rich in Pb and Sb. During the study period there were 34 pollution episodes when PM10 exceeded 50 tg m(-3), mostly due to winter air temperature inversions, regional atmospheric stagnation, or African dust incursions (North African, NAF days: usually in summer). Whereas the crustal component during NAF episodes averaged 52% with a PM2.5/PM10 ratio of 0.54, this dropped to 29% and a PM2.5/PM10 of 0.67 during non-NAF days when anthropogenic materials predominated. Abnormally enhanced concentrations of pathfinder metallic trace elements provide additional evidence for source apportionment: thus aerosols with raised levels of Pb and Sb are associated with local coal combustion, Ni and V can be linked to petrochemical PM emissions, and Ti, Mn, Rb, and Ce are particularly characteristic of crustal dust incursions.  相似文献   

12.
This study proposes a practical method to estimate elemental composition and distribution in order to attribute source and quantify impacts of aerosol particles at an urban region in Kolkata, India. Twelve-hour total particulates were collected in winter (2005–2006) and analyzed by energy-dispersive X-ray fluorescence technique to determine multi-elemental composition, especially trace metals. The aerosols consist of various elements including K, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Se, and Pb which exhibit significant concentration at various sites (p?<?0.05). The concentration of different metallic elements were found in the order of Zn ?> ?Pb ?> ?Ni ?> ?Cu ?> ?Cr ?>? Co. Statistical multivariate analysis and correlation matrix analyses were performed for factor identification and consequent source apportionment. Contour profiles demonstrate spatial variation of elemental compositions indicating possible source contribution along with meteorological influences. Spatial differences were clearly most significant for Zn, Ni, Pb, and Cu reflecting the importance of anthropogenic inputs, primarily from automobile sources.  相似文献   

13.
14.
A total of 16 people died and over 500 people were hospitalized due to diarrhoeal illness in the Bholakpur area of Hyderabad, India on 6th May 2009. A study was conducted with immediate effect to evaluate the quality of municipal tap water of the Bholakpur locality. The study consists of the determination of physico-chemical properties, trace metals, heavy metals, rare earth elements and microbiological quality of drinking water. The data showed the variation of the investigated parameters in samples as follows: pH 7.14 to 8.72, EC 455 to 769 μS/cm, TDS 303.51 to 515.23 ppm and DO 1.01 to 6.83 mg/L which are within WHO guidelines for drinking water quality. The water samples were analyzed for 27 elements (Li, Be, B, Na, Mg, Al, Si, K, Ca, V, Cr, Mn, Fe, Ni, Co, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd, Sb, Ba and Pb) using inductively coupled plasma-mass spectrometry (ICP-MS). The concentrations of Fe (0.12 to 1.13 mg/L), Pb (0.01 to 0.07 mg/L), Cu (0.01 to 0.19 mg/L), Ni (0.01 to 0.15 mg/L), Al (0.16 to 0.49 mg/L), and Na (38.36 to 68.69 mg/L) were obtained, which exceed the permissible limits of the World Health Organization (WHO) for drinking water quality guidelines. The remaining elements were within the permissible limits. The microbiological quality of water was tested using standard plate count, membrane filtration technique, thermotolerant coliform (TTC), and most probable number (MPN) methods. The total heterotrophic bacteria ranged from 1.0 × 105 to 18 × 10cfu/ml. Total viable bacteria in all the water samples were found to be too numerable to count and total number of coliform bacteria in all water samples were found to be of order of 1,100 to >2,400 MPN index/100 ml. TTC tested positive for coliform bacteria at 44.2°C. All the water samples of the study area exceeded the permissible counts of WHO and that (zero and minimal counts) of the control site (National Geophysical Research Institute) water samples. Excessively high colony numbers indicate that the water is highly contaminated with microorganisms and is hazardous for drinking purposes. Bacteriological pollution of drinking water supplies caused diarrhoeal illness in Bholakpur, which is due to the infiltration of contaminated water (sewage) through cross connection, leakage points, and back siphoning.  相似文献   

15.
Ambient air samples were collected at two different locations between 2011 and 2012 in Zhengzhou, China in order to assess the concentration level, health risks, as well as the sources of polycyclic aromatic hydrocarbons (PAHs) in particulate matter (PM2.5). The mean annual levels of PM2.5 observed at industry site and residential site were 172?±?121 and 160?±?72 μg m?3, respectively, which were about five times the annual value of proposed PM2.5 standard (35 μg m?3) in China. The PM2.5 in all daily samples (n?=?47) exceeds the proposed PM2.5 standard in China (75 μg m?3) at both industrial and residential sites. Seasonal variations of PM2.5 showed a clear trend of winter?>?autumn?>?spring?>?summer at both sites. The total concentrations of 16 PM2.5-associated PAHs ranged from 61?±?51 to 431?±?281 and 38?±?25 to 254?±?189 ng m?3, with mean value of 176?±?233 and 111?±?146 ng m?3 at industry and residential sites, respectively. The major species were fluoranthene, pyrene, chrysene, benzo[b]fluoranthene and benzo[k]fluoranthene, and the concentration levels of PAHs in PM2.5 were higher in winter than those of other seasons at both sites. The annual mean values of toxicity equivalency concentrations of ∑16PAHs in PM2.5 were 22.8 and 13.5 ng m?3 in industry and residential area, respectively. In this study, the risk level of adult citizens through inhalation exposure to PAHs was calculated. The average estimates of lifetime inhalation cancer risks were approximately 8.9?×?10?7 and 6.3?×?10?7 for industry and residential sites, respectively. The main sources of 16 PAHs from both diagnostic ratios and principle component analysis identified as vehicular emissions and coal combustion.  相似文献   

16.
Airborne particulate matter (PM10) was collected for a period of 1 year at six locations in Madurai city, India. The chemical analyses on PM10 samples were carried out for the estimation of heavy metals and ions using atomic absorption spectroscopy and ion chromatography respectively. The average PM10 concentrations varied from 97.2 to 152.5 μg/m3, which were found to be below the Indian air quality standards. While industrial areas had the highest concentrations of heavy metals such as Fe, Zn and Cr and also the $\text{SO}_{4}^{2-}$ ions, traffic areas with relatively higher traffic densities in the city endured highest concentrations of Cd and the $\text{NO}_{3}^{-}$ ion. As gaseous pollutants serve as precursors of ionic particles in the atmospheric environment, gaseous pollution control is necessitated along with particulate with special reference to heavy metal and ion pollution abatement for the sustainable development of Madurai city.  相似文献   

17.
Chemical mass balance model for source apportionment of aerosols in Bombay   总被引:1,自引:0,他引:1  
Aerosol samples collected within an industrial region of Bombay were analyzed for elemental concentrations using inductively coupled plasma emission spectroscopy, ultraviolet/visible spectrophotometry and X-ray fluorescence spectroscopy. Nineteen elements were selected as tracers of identified sources of aerosol in the region. The U.S. EPA chemical mass balance model was employed for source apportionment. Seven major source types were identified and the performance of the model was evaluated at different sampling locations. Model results were unsatisfactory at highly polluted sites in the study regions. It was found that U.S. EPA source profiles are not suitable for such regions in India and site-specific source profiles should be used in the application of chemical mass balance for source apportionment.  相似文献   

18.
杭州市居室空气中芳香族化合物污染现状及其来源解析   总被引:3,自引:0,他引:3  
用热解吸/气质联用技术研究了杭州市居室空气中芳香族化合物的组成。结果表明,杭州市居室空气中共存在60种芳香族化合物,其中苯系化合物48种,非苯芳香族化合物12种,检出率大于50%的23种;苯、甲苯、乙苯、苯乙烯、邻二甲苯、间(对)-二甲苯等10种化合物的总含量之和大于85.39%,是室内空气中主要的芳香族污染物,除萘外,其他22种污染物的平均浓度值均随装修时间间隔延长而降低;污染物主要来源是室内装修过程中使用的或装修材料中残留的有机溶剂、机动车辆排放的尾气、居民家庭中常用的清洁用品及含萘等成分的防蛀剂。  相似文献   

19.
Source contribution estimates (SCE) of school community personal Respirable Particulate Matter (RPM) have been investigated. Reported relationships of personal RPM with Ambient-outdoors and indoor RPM levels have given the concept of defining the sources of personal exposure. Ambient-outdoors, indoors, soils and local road- traffic dusts were identified as main routes and principal sources of fine particulates at personal exposure levels. Fifteen subjects (05 from each of three schools) were selected from previous conducted study of interrelationships among classified atmospheric receptors in theses schools located in Bhilai-Durg, District Durg, India. Samples of RPM collected from identified receptors and sources were analyzed for selected chemical constituents and the chemical data has been utilized in preparation of source-receptor profiles. Chemical mass balance (CMB8) model has been used for source apportionment study. Major dominating source is ambient-outdoors in case of school located near to steel plant downwind. Indoors and road-traffic dusts have also played dominating role in case of school located near to National Highways. Indoor ventilation properties have played an important role in source contribution estimates.  相似文献   

20.
Michigan water quality standards for public bathing beaches require local health departments to collect and analyze a minimum of three water samples for Escherichia coli during each sampling event. The geometric mean number of E. coli colonies is then compared to the 300 colonies per 100 ml standard to determine compliance. This article compares the results of the currently mandated procedure to a composite sampling method, whereby the three samples are mixed in equal volumes and analyzed once. This effectively replaces the geometric mean of the individual sample results with an arithmetic mean. Although arithmetic means are more affected by outliers, this sensitivity to high concentrations is more health conservative than the geometric mean. During the 2007 sampling season, nine bathing beaches were monitored once each week. Three individual point samples and a composite sample were analyzed for each sampling event. No statistically significant differences in bacteria concentrations were found between composite sample analysis and the arithmetic mean of individual point sample analyses. No violations were detected in the 2007 sampling season, so using historical data, a retrospective analysis was performed on samples gathered at nine bathing beaches in Kalamazoo County, Michigan during the years 2001–2007. The arithmetic mean of the three samples taken at each site served as a surrogate composite sample. The benefits of compositing the three samples were investigated assuming a 2/3 reduction in analytical costs. In the traditional sampling method, three individual samples were obtained and analyzed once in every 3-week period during the summer season, whereas compositing was simulated by taking the arithmetic mean of each week’s results. The results of this retrospective cost analysis indicates that ten to 14 violations would have been missed using the less frequent traditional sampling and analysis methodology. Composite sampling is a cost-saving alternative to traditional sampling techniques that can be more protective of public health, particularly when the savings are applied to increased numbers of samples in time or space.  相似文献   

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