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51.
文教区土壤环境质量直接影响学生以及职工的身体健康。本研究应用高效液相色谱仪对采集的西安市文教区表层土壤样品中的16种优控多环芳烃(PAHs)进行含量检测,分析其组分特征、来源及健康风险。结果表明,西安市文教区表层土壤中∑PAHs含量为0.290~4.147μg/g,平均值为1.515μg/g,7种致癌多环芳烃的含量为0.079~2.093μg/g,均值为0.593μg/g,土壤PAHs污染较为严重。其中4环的高环PAHs为土壤PAHs污染的主要物质,平均占∑PAHs含量的40.72%。源解析结果表明西安市文教区表层土壤中PAHs主要来源于石油燃烧、煤及生物质等的不完全燃烧。终生癌症风险评价表明西安市文教区表层土壤中PAHs污染对其生活在周围的人群产生的终生致癌风险性较小,但71.4%的样点达到严重污染水平,产生的间接影响应引起足够重视。 相似文献
52.
53.
Goyal SK 《Environmental monitoring and assessment》2003,89(3):305-314
Sodium arsenite (modified Jacobs and Hochheiser method; hereafter referred as SA), the most widely used manual monitoring method for determination of nitrogen dioxide (NO2) in ambient air, particularly in developing countries has been evaluated and compared with US EPA recommended equivalent method of TGS-ANSA (hereafter referred as ANSA). NO2 concentrations generated from laboratory test atmosphere were analyzed by these two methods and were compared statistically. Laboratory evaluations showed that SA method has high sensitivity to different sampling conditions, which normally vary during actual field monitoring. Hence, correction factors for absorption efficiency were estimated for SA and ANSA methods. Absorption efficiency of NO2 in SA method was found to be much lower (64%) as against the reported value of 82% at the method recommended sampling conditions, whereas for ANSA method, it was found 1.0 as against the reported value of 0.93. After applying derived correction factors, both the methods produced almost similar concentration values of NO2. 相似文献
54.
渤海大气气溶胶元素组成及物源分析 总被引:11,自引:0,他引:11
利用电感耦合等离子体-光发射光谱法(ICP-OES)分析了2000年夏季渤海大气气溶胶样品,给出了渤海气溶胶污染物浓度分布特点,结合气象资料和富集因子进行了元素物源分析.分析结果表明,辽东湾的污染程度高于其他海区,气溶胶中含量最高的元素是Zn(1638ng/m3),含量最低的是V(2ng/m3).渤海气溶胶中Pb、Zn、Cu和Ni等具有较高的富集因子.辽东湾Pb的富集因子达4000以上,Zn的富集因子普遍大于其他海区.Pb、Mn、Cu、V等含量的相对大小与同期北京的分析结果一致.综合分析表明,渤海大气严重受到陆地人为排放污染物的影响. 相似文献
55.
Visuthismajarni P Vitayavirasuk B Leeraphante N Kietpawpan M 《Environmental monitoring and assessment》2005,104(1-3):409-418
The potential ecological risks associated with contaminants from 15 abandoned shrimp ponds in southern Thailand were assessed at the screening level. Shrimp ponds reported as out of production for more than 2 years were selected as sampling sites. The assessment endpoint was identified as the protection of aquatic life from hazard of multiple agents or stressors in water or sediment from the ponds. The measurement endpoints were amount of toxic phytoplankton species, Yellow Head Viruses, SEMB viruses, oxytetracycline, cadmium, copper, and manganese. Data from field measurements and laboratory analyses obtained primarily from April to June 2003 were used in the risk analysis. The results showed that insignificant amounts of stressors were present, except for the metals. So, only concentration values of the metals were used in the calculation of hazard quotients (HQ) for risk characterization. The highest potential ecological risk characterized by the highest HQ value observed for each metal was 19 for manganese, 4.3 for cadmium, and 1.8 for copper. These findings indicated a need for further ecological risk assessment at a more detailed level to focus on the bioavailability and effects of metals from abandoned shrimp farms, with manganese the highest priority. 相似文献
56.
The present work attempts statistical analysis of groundwater quality near a Landfill site in Nagpur, India. The objective
of the present work is to figure out the impact of different factors on the quality of groundwater in the study area. Statistical
analysis of the data has been attempted by applying Factor Analysis concept. The analysis brings out the effect of five different
factors governing the groundwater quality in the study area. Based on the contribution of the different parameters present
in the extracted factors, the latter are linked to the geological setting, the leaching from the host rock, leachate of heavy
metals from the landfill as well as the bacterial contamination from landfill site and other anthropogenic activities. The
analysis brings out the vulnerability of the unconfined aquifer to contamination. 相似文献
57.
58.
活性炭法测量室内空气中氡浓度的影响因素研究 总被引:1,自引:0,他引:1
探讨了各种因素对活性炭法测量室内空气中氡浓度的影响,并提出既能保证检测质量,又能符合工程检测需要、提高检测效率的检测条件范围。 相似文献
59.
Kimpo metropolitan landfill has received various kinds of wastessince January 1992. The leachate level was measured to be 10.3 m in May 1995 and the level increased to 12.2 m in August 1996. Therefore, to prove the reason for the increasing leachate level, we calibrated hydraulic conductivity of each waste andintermediate layer using the HELP (Hydrologic Evaluation ofLandfill Performance) model. The leachate generation data measured from February 1993 to October 1995 was used in the model calibration. As a result of a model calibration, we obtained anaverage infiltration ratio and used this in analysis of the total water balance to predict elevation of leachate level. Main causes of the elevation of the leachate level were the high water content of the waste and the degradation of the leachate-drainage system caused by the subsidence of a naturalbarrier layer. 相似文献
60.
Soil to plant transfer factor (TF) of60Co and 65Zn was determined fromradioisotope experiments on plants grown in pots underoutdoor ambient tropical conditions for three growingseasons (1995–1998). The TFs were obtained fordifferent plants/crops such as, rice, bean, peanutspineapple, cabbage, tomato, spinach and grass. Theaverage TF values of 60Co are found to be 0.087,0.15, 0.12, 0.67, 0.28, 0.79, 1.03 and 0.34respectively for the above mentioned plants/crops. Incase of 65Zn, the average TF values are found tobe 2.24, 1.17, 0.89, 1.09, 0.78, 1.34, 2.92 and 1.78,respectively, for the above mentioned plants/crops. Thedata will be useful to assess the radiation exposureto man associated with the releases of radionuclidesfrom nuclear facilities by means of radiologicalassessment models that require transfer factors asinput parameters to predict the contamination ofradionuclides in foodchain. 相似文献