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1.
In order to get an overall picture of the environmental impact of an old municipal solid waste incinerator (MSWI) from S. Adrià del Besòs (Barcelona, Catalonia, Spain), a monitoring program addressed at determining the levels of a number of pollutants in the vicinity of the facility was initiated in 1998. In March 1999, an adaptation was carried out due to EU legislation on pollutant emissions from the stack. As a result, emissions of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) were notably reduced, and a significant (30%) decrease was found in the levels of PCDD/F in herbage samples collected in the vicinity of the MSWI. In March 2001, herbage samples were collected at the same sampling points and the PCDD/F levels measured again. The current PCDD/F concentrations range from 0.23 to 1.43 ng I-TEQ kg(-1) (dry matter), with median and mean values of 0.58 and 0.66 ng I-TEQ kg(-1) (dry matter), respectively, while in the 2000 survey the PCDD/F concentrations ranged from 0.22 to 1.20 ng I-TEQ kg(-1) (dry matter), with median and mean values of 0.57 and 0.61 ng I-TEQ kg(-1) (dry matter), respectively. Although the current PCDD/F concentrations in herbage samples are comparable to those found in recent surveys carried out in various places of Catalonia, an exhaustive evaluation of the data, including principal component analysis, indicates that other emission sources of PCDD/Fs also have a notable environmental impact on the area under direct influence of the MSWI.  相似文献   

2.
The soils at a factory for manufacturing pentachlorophenol were heavily contaminated by polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). In order to verify the contributions of dry and wet deposition of PCDD/Fs from the ambient air, the concentration of PCDD/Fs in ambient air and soil were measured, the partition of particle- and gas-phases of atmospheric PCDD/Fs was calculated, and the annual fluxes of total dry and wet PCDD/F depositions were modeled. Average atmospheric PCDD/F concentration was 1.24 ng Nm???3 (or 0.0397 ng I-TEQ Nm???3). Moreover, over 92.8% of total PCDD/Fs were in the particle phase, and the dominant species were high chlorinated congeners. The total PCDD/F fluxes of dry and wet deposition were 119.5 ng m???2 year???1 (1.34 ng I-TEQ m???2 year???1) and 82.0 ng m???2 year???1 (1.07 ng I-TEQ m???2 year???1), respectively. By scenario simulation, the total fluxes of dry and wet PCDD/F depositions were 87.1 and 68.6 ng I-TEQ, respectively. However, the estimated PCDD/F contents in the contaminated soil were 839.9 ?? g I-TEQ. Hence, the contributions of total depositions of atmospheric PCDD/F were only 0.02%. The results indicated that the major sources of PCDD/F for the contaminated soil could be attributed to the pentachlorophenol manufacturing process.  相似文献   

3.
深圳市大气中PCDD/Fs污染水平初步研究   总被引:1,自引:1,他引:1  
目的:了解深圳市大气中二噁(PCDD/Fs)的污染水平和分布特征。方法:利用大流量空气采样器分别采集6个采样点的空气样品,每个采样点采集两个平行样品。参照美国环保总局(US EPA Method TO-9A)二噁的检测方法,通过高分辨气相色谱-高分辨双聚焦磁式质谱仪(HRGC/HRMS)对大气样品中17种具有毒性当量因子(TEF)的单体进行了定性和定量分析。结果:∑PCDD/Fs的浓度范围为0.23~11.88pg/m3(平均值为3.84 pg/m3)。毒性当量浓度范围为0.014~0.29 pg I-TEQ/m3(平均值为0.135 pg I-TEQ/m3)。OCDD、HpCDD、HpCDF、OCDF、HxCDF是丰度较大的单体,分别占总浓度的48.21%、15.85%、11.37%、7.40%、6.59%。PCDDs和PCDFs单体浓度(除OCDF之外)均随氯原子取代个数的增加而增大。2,3,4,7,8-PeCDF对总的毒性当量贡献最大,占总毒性当量浓度的38.87%。六个采样点中有三个地点二噁同系物分布显示了"源"的特征,而另外三个地点则显示了"汇"的特征。成人的PCDD/Fs暴露量为0.0023~0.047 pg I-TEQ/kg.day;儿童PCDD/Fs暴露量为0.0052~0.11 pg I-TEQ/kg.day。结论:深圳市大气样品中二噁浓度低于国内一些城市研究水平,而高于日本、欧美国家的研究水平。  相似文献   

4.
利用同位素稀释高分辨气相色谱-高分辨质谱(HRGC/HRMS)的分析方法研究了东北某钢铁厂及其周围生活区、背景对照区土壤中二噁和多氯联苯污染物的污染水平和分布规律。结果表明,土壤中二噁的浓度和毒性当量分别为26pg/g(6.02~109pg/g)、0.72pg I-TEQ g-1(0.008~5.43pg I-TEQ g-1)。土壤中多氯联苯的浓度为955pg/g(268~3504pg/g),毒性当量值达0.07pg TEQ g-1(0.006~0.33pg TEQ g-1)。该区域土壤中的二噁和多氯联苯浓度明显低于一般国家居住地的土壤控制标准,处于较低的污染水平。  相似文献   

5.
2004年夏季在广州四个不同区域采集大气颗粒物样品,参照美国环保局(US EPA)标准方法测定其中二噁的含量,采用热分解光学分析法测定元素碳和有机碳的含量。结果表明,花都、荔湾、天河、黄埔大气颗粒物中二噁浓度(毒性当量)平均值分别为3815fg/m3(104.6fg I-TEQ/m3)、12777fg/m3(430.5fg I-TEQ/m3)、6963fg/m3(163.7fg I-TEQ/m3)、10953fg/m3(769.3fg I-TEQ/m3)。简单地分析了广州大气颗粒物中二噁的含量特征,以及与元素碳、有机碳之间的相关性。  相似文献   

6.
This study is the first to investigate the contamination of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) on surface soils in the vicinity of the first hazardous waste incinerator of Turkey. In the study, 24 soil samples were taken from a 1625-m-radius circle whose center is the stack of the incinerator. This process was repeated 1 year later. Since the acquired average PCDD/F concentrations of the two sampling campaigns (0.05 and 0.02 ng WHO-toxic equivalent (TEQ)/kg) were meaningfully low compared to the related literatures, a new sampling campaign was carried out to control this inconsistency, but this time in a foreign laboratory (0.56 ng WHO-TEQ/kg). In the same period, eight gas samples were taken from the stack under different operational conditions of the facility. According to the evaluations of the findings, the geographical-meteorological data of the study area and the specific operational conditions of the facility corroborate the concentrations of the first and the second soil samplings rather than the third one. The major underlying reason for the inconsistency of the soil concentrations may be the fact that the data analysis procedures used by the laboratories are different. The author suggests a hypothesis which argues that the soils in the vicinity of a hazardous waste incinerator may have significantly lower concentration levels than in related literatures.  相似文献   

7.
杭州市环境空气中二噁英类物质检测与分析   总被引:2,自引:0,他引:2  
为了解二噁英类物质(PCDD/Fs)在环境空气中污染现状及不同季节不同时段浓度、组成和存在形式等的变化情况,于夏、冬两季对杭州西湖区空气中PCDD/Fs进行了采样分析。结果表明,空气中PCDD/Fs毒性当量浓度与国内其他城市(北京、上海、广州)相近,夏、冬两季空气中PCDD/Fs质量浓度和毒性当量浓度分别为4.92 pg/m3、0.34 I-TEQ pg/m3和4.51 pg/m3、0.40 I-TEQ pg/m3,夏季PCDD/Fs毒性当量浓度略低于冬季;在分时段采样检测结果中,晚间空气中PCDD/Fs质量浓度和毒性当量浓度均高于白天空气中的PCDD/Fs浓度;夏季样品中TCDD/Fs、PeCDD/Fs主要以气相的形式存在,HpCDD/Fs、OCDD/F主要以颗粒相的形式存在,冬季样品中PCDD/Fs主要以颗粒相形式存在。  相似文献   

8.
We investigated the occurrence and distribution patterns of 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in six sediment samples from the Xiangjiang River, Hunan Province, People’s Republic of China. Total concentrations of PCDD/Fs ranged from 876 to 497,759 (mean 160,766) ng/kg dw, the highest of which exceeded that have ever been reported for sediment samples. World Health Organization total toxicity equivalent (WHO-TEQ) concentrations in three out of six samples were significantly higher than the guidance level (21.5?ng WHO-TEQ/kg dw) suggested by Canadian Sediment Quality Guideline. A predominance of octachlorodibenzo-p-dioxin (OCDD) was observed with an average contribution of 90.8% to the total PCDD/F concentrations, while 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin (HpCDD) was the major contributor to the PCDD/F WHO-TEQ concentrations in most of the sites. Such high levels of OCDD and HpCDD may be attributed to the presence of PCP/PCP-Na pollution, although MB-WW, agricultural straw open burning, and boilers–hazardous wastes were also the potential sources of PCDD/Fs. This is the first report for the concentrations and congener profiles of PCDD/Fs in sediment samples from the Xiangtan, Zhuzhou, and Changsha sections of the Xiangjiang River, providing scientific evidence for establishing priorities to reduce ecological risks posed by PCDD/Fs in the rapidly developing areas of Hunan Province and elsewhere.  相似文献   

9.
通过对上海市危险废物焚烧行业焚烧炉排放烟气数据的分析,结果表明:不管是医疗废物焚烧炉还是一般危险废物焚烧炉,其二蟋英分布规律大致相同;PCDFs对二曝英的贡献率远高于PCDDs;实测检出的二嚼英异构体中,占二嚼英总量比例较大的依次为1,2,3,4,6,7,8-HpCDF、1,2,3,4,6,7,8-HpCDD和OCDD;I—TEQ贡献最高的二嚼英异构体为2,3,4,7,8-PeCDF,贡献率达31.08%~53.56%。17种二喏英异构体与I—TEQ的相关性分析表明,仅2,3,4,7,8-PeCDF在2类焚烧炉中与I—TEQ均存在相关性,其相关系数分别为0.989和0.998,可以作为潜在的测定指示物。  相似文献   

10.
Reports on residue levels and accumulation profiles of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in human adipose tissue are scarce in Korea. In this study, concentrations and accumulation features of PCDD/Fs and DL-PCBs were determined in the samples of adipose tissue collected from Korean women in 2007-2008. The total dioxin-like toxic equivalent (TEQ) concentrations (3.4-42 pg g(-1) lipid wt) in Korean adipose tissues were similar to those reported in European and other Asian countries. The relative contributions of individual compounds to total TEQs were as follows: non-ortho PCBs (mean: 45%) > PCDFs (28%) > PCDDs (24%) > mono-ortho PCBs (3%), a pattern similar to those reported for seafoods in Korea. The dominant PCDD/F congeners found in adipose tissues were OCDD and 2,3,4,7,8-PeCDF and dominant PCBs were 118, 156 and 105. No correlation was found between subject's age and concentrations of dioxin-like contaminants. Body mass index was not correlated with concentrations of PCDD/Fs and was negatively (p < 0.001) correlated with concentrations of DL-PCBs. The results of this study provide baseline information on PCDD/Fs and DL-PCBs in adipose tissues of the general population in Korea.  相似文献   

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