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91.
Cadmium and lead were determined in different tissues (muscle,gill, stomach, intestine, liver, vertebral column and scales) of Tilapia nilotica from the High Dam Lake, Aswan (Egypt) to assess the lake water pollution with those toxic metals. Fish samples were chosen from different ages and weights to be analyzed along with samples of the aquatic plant(Najas armeta), sediment and lake water.The results showed that cadmium and lead concentrations were higher in fish scales and vertebral column than in the other parts of the fish. Cadmium and lead levels in High Dam lake water and fish (Tilapia nilotica) were a result of the pollution which uptakes from aquatic plants, sediments andgasoline containing lead that leaks from fishery boats. Tilapia nilotica fish was used as a good bio-assay indicator for the lake pollution with cadmium and lead. The fish musclesin this study were in the safety baseline levels for man consumption.  相似文献   
92.
Existing methods of establishing ambientair quality monitoring networks typically evaluateonly parameters related to ambient concentrations ofthe contaminant(s) of interest such as emissionsource characteristics, atmospheric transport anddispersion, secondary reactions, depositioncharacteristics, and local topography. However,adverse health risks from exposures to airbornecontaminants are a function of the contaminant andthe anatomic and physiologic characteristics of theexposed population. Thus, ambient air qualitymonitoring networks designed for the protection ofpublic health or for epidemiological studiesevaluating adverse health impacts from exposures toambient air contaminants should account for bothcontaminant characteristics and human healthparameters. A methodology has been establishedwhich optimizes ambient air quality monitoringnetworks for assessments of adverse human healthimpacts from exposures to airborne contaminants byincorporating human health risk assessmenttechniques. The use of risk assessment techniquesas the basis for designing ambient air qualitymonitoring networks will help to target limitedfinancial and human resources to evaluate humanhealth risks from exposures to airbornecontaminants.  相似文献   
93.
Swine Concentrated Animal Feeding Operations (CAFOs) have received much attention in recent years. As a result, a watershed-based screening tool, the Cumulative Risk Index Analysis (CRIA), was developed to assess the cumulative impacts of multiple CAFO facilities in a watershedsubunit. The CRIA formula calculates an index number based on: 1) the area of one or more facilities compared to the area of the watershed subunit, 2) the average of the environmental vulnerability criteria, and 3) the average of the industry-specific impact criteria. Each vulnerability or impact criterion is ranked on a 1 to 5 scale, with a low rank indicating low environmental vulnerability or impact and a high rank indicating high environmental vulnerability or impact. The individual criterion ranks, as well as the total CRIA score, can be used to focus the environmental analysis and facilitate discussions with industry, public, and other stakeholders in the Agency decision-making process.  相似文献   
94.
悬浮物对三峡水库水质测定结果的影响   总被引:1,自引:1,他引:1  
以长江寸滩断面和嘉陵江大溪沟断面水样为测定样品,探讨了悬浮物对三峡水库水质测定结果的影响,提出在三峡水库水质监测中,应对经0.45μm滤膜过滤的滤液进行指标测定,同时测定悬浮物含量,并对悬浮物进行组分分析;建议在地表水环境质量标准中,纳入悬浮物项目。  相似文献   
95.
北京市地表水环境面临的主要问题及防治对策   总被引:6,自引:2,他引:6  
针对北京市地表水水质污染现状、污染特点及其变化趋势,深入剖析了目前地表水环境及其治理过程中存在的主要问题,提出进一步改善北京市地表水环境的措施与建议。  相似文献   
96.
粗苯污染事故应急处理   总被引:3,自引:0,他引:3  
针对一次苯泄漏事故的应急处理过程、方法进行论述与总结,并分析了事故现场周围地表、地下水中苯污染浓度的变化情况,提出了该类事故的应急措施,以此作为处理同类事故的参考和依据。  相似文献   
97.
博乐市空气质量变化趋势分析   总被引:2,自引:0,他引:2  
分析了博乐市2001-2005年空气质量监测数据在不同月份、不同年份、不同污染因子的变化趋势,并结合当地能源结构、地理位置、气候特征、城市环境综合发展水平。指出影响博乐市空气质量的主要因素,为防治或减轻博乐地区的空气污染提供了科学依据。  相似文献   
98.
This article presents and discusses SO2 (ppbv) concentration measurements combined with meteorological data (mainly wind speed and direction) for a five-year campaign (1996 to 2000), in a site near an oil refinery plant close to the city of La Plata and surroundings (aprox. 740.000 inh.), considered one of the six most affected cities by air pollution in the country. Since there is no monitoring network in the area, the obtained results should be considered as medium term accumulated data that enables to determine trends by analyzing together gas concentrations and meteorological parameters. Preliminary characterization of the behaviour of the predominant winds of the region in relation with potential atmospheric gas pollutants from seasonal wind roses is possible to carry out from the data. These results are complemented with monthly averaged SO2 measurements. In particular, for year 2000, pollutant roses were determined which enable predictions about contamination emission sources. As a general result we can state that there is a clear increase in annual SO2 concentration and that the selected site should be considered as a key site for future survey monitoring network deployment. Annual SO2 average concentration and prevailing seasonal winds determined in this work, together with the potential health impact of SO2 reveals the need for a comprehensive and systematic study involving particulate matter an other basic pollutant gases.  相似文献   
99.
This paper uses a dynamic model to explore the issue of irrigation-induced salinity, which puts irrigation at risk in most irrigated areas throughout the world. We address the design of instruments that an irrigation district board could implement to induce irrigators to take sustainable irrigation decisions. In our approach, the irrigators located above an aquifer participate in the accumulation of groundwater, a stock pollution. We analyse input-based instruments to induce the agents to follow the optimal stock path.  相似文献   
100.
测定总氮的影响因素探讨   总被引:12,自引:2,他引:12  
针对水质中总氮测定时蒸馏水、消解剂和消化过程等影响因素进行了讨论,并提出了减小空白值的对策。  相似文献   
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