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1.
电子垃圾拆解对台州氯代/溴代二噁英浓度和组成的影响   总被引:1,自引:0,他引:1  
电子垃圾拆解会导致有毒有害污染物向大气的排放,造成环境污染的产生。为了解电子垃圾拆解及废旧金属再生活动对拆解地及邻近地区空气质量的影响,对台州峰江金属再生园区附近及对照区路桥市区大气中(气态和颗粒态)氯代二噁英(PCDD/Fs)、溴代二噁英(PBDD/Fs)的含量、同系物组成及气/固分配规律进行了研究,通过相关性分析探讨了PCDD/Fs和PBDD/Fs的可能来源。结果显示,金属再生园区冬季采样期间17种2,3,7,8-PCDD/Fs和8种2,3,7,8-PBDD/Fs的平均浓度分别为212.2 pg·m-3和17.6 pg·m-3,夏季采样期间的平均浓度分别为84.5 pg·m-3和5.4 pg·m-3,均显著高于对照点。夏季采样期间对照点处于再生园区的下风向,其二噁英浓度高于冬季,说明其受到了金属再生园区的明显影响。基于相关性分析的结果,塑料焚烧是金属再生活动中氯代和溴代二噁英的主要来源。初步的暴露风险评价表明,金属再生园区附近居民每日摄入的二噁英含量远远超过世界卫生组织规定的人体每日耐受量(1~4 pg W-TEQ·kg-1·d-1)。上述研究结果为规范电子垃圾拆解活动提供了基础数据。  相似文献   

2.
对广州市珠江隧道中气相和颗粒态样品,以及隧道附近大气样品中的二噁英类化合物(PCDD/Fs)进行了检测.结果表明,珠江隧道中17种2,3,7,8-氯取代二苯对二噁英和二苯并呋喃(包括气相和颗粒态)的浓度范围夏季(7月)为3830.9 fg·m-3-4690.2 fg·m-3,毒性当量为193.0 fg·I-TEQ·m-3-217.0fg·I-TEQ·m-3;冬季(12月)为18600.8 fg·m-3-20388.8 fg·m-3,毒性当量为1275.4fg·I-TEQ·m-3-1392.2 fg·I-TEQ·m-3;冬季浓度远远高于夏季,隧道内冬季浓度是夏季浓度的3-4倍.环境大气样品中PCDD/Fs浓度低于隧道.同时期样品中,隧道出口、隧道中间、隧道外以及沙面公园中PCDD/Fs的浓度呈递减趋势,并且在冬季这种趋势更加明显,冬季隧道内浓度是环境大气浓度的2倍(毒性当量为5倍).加权平均后PCDD/Fs的排放因子值为1994.6 pg·km-1·辆-1(104.8 pg I-TEQ).  相似文献   

3.
为探究二噁英(PCDD/Fs)合适的指示物,本文研究了国内两座生活垃圾焚烧电厂的两台循环流化床炉A、B的PCDD/Fs及氯苯(CBzs)排放特性.同时利用统计分析软件(SPSS)分析了PCDD/Fs浓度、TEQ浓度、CBz浓度之间的相关性.结果显示,在17种有毒PCDD/Fs中,2,3,4,7,8-P5CDF是最主要的二噁英同系物,在焚烧炉A、B中分别占毒性当量(TEQ)的28.97%—49.42%和45.56%—56.23%.氯苯的排放以二氯苯(DCBzs)、三氯苯(Tr CBzs)为主,其浓度是PCDD/Fs的几千倍.当用CBz作PCDD/Fs和TEQ的指示物进行一元线性回归分析时,发现部分指示物有很高的相关系数,R2最高可达0.8642.  相似文献   

4.
孙俊玲  王鹏焱  张庆华 《环境化学》2019,38(7):1582-1589
为探讨不同交通状况下大气颗粒物中二■英(PCDD/Fs)的污染特征以及评估交通限行对大气颗粒物中二■英(PCDD/Fs)变化趋势的影响,在中国地质大学(北京)东门使用中流量采样器对大气颗粒物PM_(10)和TSP样品进行了连续同步采集,应用同位素稀释高分辨率气相色谱/高分辨率质谱(HRGC/HRMS)联用法和US EPA 1613B标准方法,检测分析了北京市交通限行期间以及交通限行前后等不同交通状况下大气颗粒物TSP和PM_(10)中17种2,3,7,8-氯取代PCDD/Fs浓度及其变化特征,结果显示,PCDD/Fs在TSP中的浓度和毒性当量(TEQ)分别是交通限行前2117 fg·m~(-3)(120.85 fg I-TEQ·m~(-3))、限行期间550 fg·m~(-3)(25.26 fg I-TEQ·m~(-3)),在PM_(10)中的浓度(毒性当量)分别是交通限行前2045 fg·m~(-3)(112.87 fg I-TEQ·m~(-3))、限行期间484 fg·m~(-3)(19.67 fg I-TEQ·m~(-3))、限行结束后1572 fg·m~(-3)(81.06 fg I-TEQ·m~(-3)). PCDDs浓度远低于PCDFs,体现了典型"热源"特征,除OCDF外,PCDDs和PCDF同族体浓度变化趋势表现为随着取代氯原子个数的增加而增大,PCDD/Fs主要附着在PM_(10)中,占TSP中总浓度的87%—97%,平均92%.交通限行期间PCDD/Fs污染水平明显降低,临时交通流控制措施是PCDD/Fs降低的主要因素.当前的研究结果力求为评价交通源对大气环境中PCDD/Fs的影响以及交通限行对PCDD/Fs的削减贡献提供支撑.  相似文献   

5.
基于焚烧过程中二噁英类(PCDD/Fs)的生成机理,深入探讨生活垃圾焚烧设施二噁英类生成及排放的诸多影响因素,并依据层次分析法(AHP)原理,从焚烧设施的技术水平、运行状况、管理水平3个影响因素着手建立递阶层次结构模型.分别对模型中的各个影响因素进行定性和半定量化处理,最终实现对生活垃圾焚烧设施二噁英类生成及排放影响因...  相似文献   

6.
对25个苏南城市群河流表层沉积物中二噁英及17个样品中共平面多氯联苯的监测表明,PCDD/Fs和dl-PCBs中位值分别为6.61 ng WHO1998TEQ·kg-1和1.43 ng WHO1998TEQ·kg-1,均处于我国和亚洲河流表层沉积物的中等水平.PCDD/Fs和dl-PCBs含量水平与经济发展水平和工业规模呈现正相关.开发区新建企业是PCDD/Fs的新排放源之一.统计分析表明,南通PCDD/Fs的排放以燃煤和农药五氯酚的使用为主,无锡来源于农业活动和少量工业污染源,苏州则受到目前工业排放源的影响,3个城市的PCBs主要来源于历史上PCBs工业品的使用.96%的采样点总毒性当量浓度(TEQ)超过加拿大沉积物质量指导值(ISQGs),88%的采样点超过美国EPA ISQGs,表明苏南城市群表层沉积物PCDD/Fs和dl-PCBs具有一定生态风险.  相似文献   

7.
为了解北京市大气细颗粒物(PM_(2.5))中二■英(PCDD/Fs)的污染特征,利用中流量大气颗粒物采样器,在北京市3个功能区5个采样点(两个市区点、两个工业区点和一个背景点),同步连续采集了大气细颗粒物PM_(2.5)样品.参照US EPA 1613B标准方法,应用高分辨率气相色谱/高分辨率质谱(HRGC/HRMS),分析了PM_(2.5)中17种PCDD/Fs的浓度水平和区域分布特征,并对PCDD/Fs的污染来源做了初步探讨.结果表明,5个采样点PM_(2.5)的日均质量浓度范围102—146μg·m~(-3),平均日均值119μg·m~(-3),超出国家二级标准(75μg·m~(-3))59%,污染较重.在空间分布上,PM_(2.5)的日均浓度表现为工业区大于背景点大于市区的特征.所有采样点17种PCDD/Fs的总浓度范围∑PCDD/Fs是1.60—4.09 pg·m~(-3),平均值3.23 pg·m~(-3),PCDD/Fs总毒性当量∑TEQ范围是140.54—275.69 fg I-TEQ·m~(-3),平均值233.18 fg I-TEQ·m~(-3).与国内外其他城市相比,北京市大气PM_(2.5)中PCDD/Fs污染处于相当或略高水平.OCDD、OCDF和1,2,3,4,7,8-HpCDF是PCDD/Fs的主要组成成分,分别占总浓度∑PCDD/Fs的10%、19%和24%.对于总毒性当量∑TEQ贡献最大的是2,3,4,7,8-PeCDF,占总毒性当量的48.3%,∑PCDDs/∑PCDFs比值范围为0.19—0.23,平均值0.22,属于典型的"热源"特征.在浓度变化上, PCDDs呈现为随氯取代个数的增加而增加,除OCDF外, PCDFs的各单体浓度也随着取代氯原子个数的增加而增大.在区域分布上,PCDD/Fs浓度表现为工业区高于市区,市区大于背景点,充分体现了局地源的特点.采样期间工业热过程(化石燃料燃烧、电弧炉、烧结和冶炼等)、机动车排放和固体垃圾焚烧是北京冬季大气PM_(2.5)中PCDD/Fs和PM_(2.5)污染水平的主要影响因素.  相似文献   

8.
用高分离能力的气相色谱-高分辨质谱(HRGC-HRMS)核实二噁英/呋喃是一项昂贵又费时的分析工作,需要高素质的仪器操作人员,而在认证分析前采用筛选法检查样品是检测不出还是浓度超出HRGC-HRMS方法定量范围,可以大大地减少HRGC-HRMS实验室的工作负荷.最新提供的信息表明约10%筛选过的样品需用HRGC-HRMS认证/核实.有些GC/MS/MS方法需要多次进样以获得有毒和无毒的PCDD/Fs,或用功能变换法[1-4]可以确保检测出所有的有毒的2,3,7,8-氯代PCDD/Fs,但损失某些无毒的PCDD/Fs(2,3,7,8氯代PCDD/Fs除外).  相似文献   

9.
在北京市市区/交通干道(A地质大学东门、B地质大学测试楼顶),工业区(C首钢焦化、D高井热电厂)和背景点(E十三陵),同时采集了冬季大气颗粒物PM_(10)样品.利用US EPA 1613B方法,采用同位素稀释、高分辩率气相色谱/高分辩率质谱(HRGC/MS)联用技术,对比分析了PM_(10)中17种二噁英(PCDD/Fs)的浓度水平和区域分布特征.结果表明,5个采样点PM_(10)的质量浓度范围是140—264μg·m~(-3),日均值为184μg·m~(-3)比国家二级标准(150μg·m~(-3))高23%.所有采样点17种PCDD/Fs的总浓度范围1.96—4.80 pg·m~(-3),平均值3.69 pg·m~(-3),总毒性当量∑TEQ范围是148—353 fg I-TEQ·m~(-3),平均271 fg I-TEQ·m~(-3);PCDD/Fs污染水平最高出现在工业区,其次是市区,背景点最低.  相似文献   

10.
2013年9月采集洞庭湖区三口四水入湖口,东、西、南洞庭湖湖区以及出湖口沉积物,采用同位素稀释高分辨气相色谱-高分辨质谱法测定了沉积物中的二噁英(PCDD/Fs).结果表明洞庭湖沉积物中二噁英的浓度范围为153—7144 pg·g-1dw(干重),小河嘴最低,虞公庙最高.对比国内外其他淡水湖泊河流二噁英浓度,洞庭湖污染程度相对较低.二噁英污染水平依次为洞庭湖湖区出湖口入湖口,湖区内污染水平依次为南洞庭湖东洞庭湖西洞庭湖.主要同类物为OCDD,贡献率范围为77%—97%.PCDD/Fs的污染水平比1995年下降1—2个数量级,但和2004年污染水平相当.沉积物中二噁英的含量与水的流速成反比.洞庭湖出口处PCDD/Fs浓度相比入湖口和湖区浓度处于中间水平,表明洞庭湖中的二噁英可能会随水流进入长江中下游.  相似文献   

11.
北京市农业区不同使用类型土壤中二噁英类分析   总被引:1,自引:0,他引:1  
2005年6—7月采集了北京市农业区不同使用类型土壤样品24个,分别为蔬菜地8个、粮地8个、果园地8个,采用高分辨气质联机对17种二噁英类进行了分析.结果表明:所有样品中二噁英浓度范围为,0.26—5.74(平均值为1.51)pgI-TEQ.g-1;蔬菜地浓度范围为,0.26—5.62(平均值1.75)pgI-TEQ.g-1;粮地浓度范围为,0.45—5.74(平均值2.02)pgI-TEQ.g-1;果园地浓度范围为,0.34—2.02(平均值0.73)pgI-TEQ.g-1;三种类型中粮食地浓度最高,其次为蔬菜地,果园地浓度最低.与国外农业区土壤中的二噁英浓度相比而言,北京市相对较低.所有样品中,样品8和16浓度异常高,但是8.3%(2:24)的高浓度样品数并不代表对人体有害.由于样品24处于垃圾焚烧炉旁边,也对此进行了详细的分析.样品中二噁英类物质形态分布出现了极大的离散性,这表明农田土壤中二噁英可能是多种因素综合作用的结果,例如:除草剂的使用、秸秆等固体废弃物的焚烧、汽车尾气排放等.  相似文献   

12.
不同垃圾焚烧炉产生的PCDD/Fs和PCBs同类物的分布   总被引:2,自引:1,他引:2  
要应用高分辨气相色谱一质谱联用技术,测定了3种垃圾焚烧炉产生的飞灰中17种PCDD/Fs和12种共平面PCBs的浓度及毒性当量,比较了PCDD/Fs和PCBs同类物分布的差异.结果表明,流化床焚烧炉和炉排焚烧炉产生的PCDD/Fs多于PCBs,而气化熔融焚烧炉产生的PCBs多于PCDD/Fs;产生的PCBs对总毒性当量的贡献都比较小;3种焚烧炉产生的PCDD/Fs同类物具有相似的浓度分布;流化床焚烧炉和炉排焚烧炉产生的PCBs同类物具有相似的浓度分布,而气化熔融焚烧炉产生的PCBs同类物分布与其他两种焚烧炉差别较大.  相似文献   

13.
上海地区大气中二噁类分布特征的初步研究   总被引:1,自引:0,他引:1  
为了研究上海地区大气中二噁英(PCDD/Fs)的污染水平、分布特征和相分配规律,分别选取了上海典型的工业区、居民区和郊区的采样点进行了大气样品的采集。通过对3个采样点的研究发现,上海地区的大气中二噁英的平均毒性当量浓度为0.201 pg/m^3,居民区最高,工业区其次,郊区最低。大气中二噁英排放的平均浓度属于典型的城市工业区水平。在常温下,大气中90%二噁英主要分布在颗粒物相中,从单体看,高氯代同系物主要分布在颗粒相中,而低氯代同系物则分布在气相当中。通过二噁英的气相/颗粒相分配系数Kp与蒸气压PL的关系式评价了污染物的气相/颗粒相分配行为。并应用Junge-Pankow模型预测了大气中的气相/颗粒相分配,通过与实测值的比较发现,上海地区大气中二噁英的气相/颗粒相分布十分接近于模型中的城市地区,郊区采样点和模型预测值最为吻合,工业区和居民区大气中的二噁英在颗粒物上的浓度则要高于模型预测值,对造成偏离的原因进行了分析,并对3个采样点周围的污染源进行了初步的探究。  相似文献   

14.
The emerging issue of electronic wastes (e-waste) and the associated environmental problems has gained considerable attention from the scientific community in recent decades. In the present study, the levels of polybrominated diphenyl ethers (PBDEs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the surface soil obtained from the Taizhou e-waste recycling area of China were investigated. Also the correlation among these chemicals and previously published data of heavy metals, polycyclic aromatic hydrocarbons, and polychlorinated biphenyls was analysed. We determined that the pollution levels of eight PBDEs congeners were serious, ranging from 27.9 to 3128.4 μg/kg. The concentration of PCDD/Fs was in the range of 218.3–3122.2 pg/g with a mean value of 659.5 pg/g. The PBDEs were not well-correlated with organic pollutants (PAHs and PCBs) in soil, whereas PCDD/Fs exhibited a significant positive correlation with the PCBs. The higher levels of persistent organic pollutants may pose potential adverse effects to soil quality and human beings and needs to be properly managed and remediated.  相似文献   

15.
In order to better understand the environmental behaviors of persistent organic pollutants, the characteristics of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were investigated in twenty-three soil/sediment samples from Baiying City, Northwest China, in 2008. The possible sources and potential health risk of PCDD/Fs were also discussed. The concentrations of PCDD/Fs in nineteen soil samples varied between 20.13 and 496.26 pg/g dry weight (dw.), with an average value of 125.59 pg/g dw. The highest International Toxic Equivalent (I-TEQ) of PCDD/Fs (8.34 pg/g dw.) in soil was found at sample S1 collected from proximity to a copper metallurgy plant. The concentrations of PCDD/Fs in four sediment samples ranged from 37.69 to 491.49 pg/g dw., with an average value of 169.95 pg/g dw. The highest I-TEQ of PCDD/Fs (8.56 pg/g dw.) in sediment was found at sample S12 collected from the East big ditch with waste water discharged into the Yellow River. The results indicated that PCDD/Fs contamination of soil/sediment is originated from three sources: chlorine-containing chemicals, non-ferrous metal industrial PCDD/Fs emission and coal burning. The health risk exposure to PCDD/Fs through soil, dust ingestion and dermal absorption ranged from 0.0006 to 0.0134 pg/kg/day Word Health Organization’s toxic equivalent in 1998 (WHO1998-TEQ) with mean values 0.0032 pg WHO1998-TEQ for adults and varied between 0.0012 and 0.0256 pg/kg/day WHO1998-TEQ with mean values 0.006 pg/kg/day WHO1998-TEQ for children, respectively. These results indicated that health risk of PCDD/Fs for children should be paid more attention.  相似文献   

16.
Secondary copper production is one of the key polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) emission sources in China, but research and data on this issue are rare. In 2004, when the Stockholm Convention entered into force in China, PCDD/Fs emissions from secondary copper production contributed to 32.2% of the total release. In this paper, PCDD/Fs emission dynamics from secondary copper industry were discussed and cumulative risks were characterized. From 2004 to 2009, industrial policies played an indirect role in PCDD/Fs reduction, but its effects are still limited. The Yangtze River Delta, Pearl River Delta and central regions were among the top three of dioxin emissions from secondary copper production in China. Shanghai, Shandong, Zhejiang, and Jiangxi had comparatively higher accumulated risk and were recommended as the priority regions for promoting PCDD/Fs emission control in China. From 2009 to 2015, the PCDD/Fs emission dynamics in the secondary copper industry were presented through simulation. PCDD/Fs emission equations were established, resulting in the recommendation of control technology conversion rate at 30% for small scale smelters and 51%–57% for large and medium-sized enterprises in 2015. In conclusion, both indirect policy and direct control technology retrofitting should be integrated for more effective PCDD/Fs emission reduction in secondary copper industry.  相似文献   

17.
Baltic salmons were caught from two Latvian rivers during the spawning seasons of 2010 and 2011 for the determination of seventeen 2,3,7,8-chlorine-substituted dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and 12 dioxin-like polychlorinated biphenyls (PCBs). A partially automated clean-up procedure was used for sample preparation, followed by capillary gas chromatography hyphenated to high-resolution mass spectrometry. The concentrations of PCDD/F&;PCB-TEQ ranged from 6.6 to 18.2?ng?kg?1 fresh weight and this confirms the previous reports of relatively high concentrations of PCDD/Fs, and especially of dioxin-like PCBs in Baltic wild salmon, in most samples exceeding maximum recommended levels (MRLs) in toxicity equivalency quotients (PCDD/F-PCB-TEQ) of the World Health Organization (WHO 1998) according to EC COMMISSION REGULATION No 1881/2006. The results suggest that high consumption of Baltic wild salmon could entail the risk of exceeding the TDI for adults and teenagers. Extra care must be taken when Baltic wild salmon is included in childrens's diet to avoid exceedance of the recommended TDI of 4?pg?kg?1 body weight for this group.  相似文献   

18.
In connection with law-imposed waste disposal regulations concerning the modernisation of the incineration ?Munich-North“, local authorities and residents raised objections. Based on an immission calculation using a numerical model concerning the impact of PCDD/PCDF on the soil (study I), conclusions were drawn that the former immissions were so high that further impact on the soil by a new combustion plant was no longer tolerable. The results of study I were controlled using a different numerical model calculation (study II). The simulation results varied vastly because of the differences in preliminary input parameters. In order to verify the simulations, soil samples were taken and the content of PCDD/PCDF was determined. Predicted soil-contents of study II were in the same range as the analyzed samples, whereas the values of study I were higher. With one exception, the soil contents were less than 5 ng TEQ-BGA kg?1 mT, a value below the BGA limits. Calculations by numerical modelling, compared to the measurement of PCDD/PCDF soil contents, are therefore no reliable basis for predicting PCDD/PCDF concentrations in soils which has been induced by incineration emission.  相似文献   

19.
For the estimation of intestinal absorption of polychlorianted dibenzodioxins/dibenzofurans (PCDD/F), ain-vitro model was developed in order to study PCDD/F mobilization by digestion of technogenic soils using ?Kieselrot” (red slag) as substrate and digestive juice model mixtures. Red slag samples were shaken successively with model mixtures of saliva, gastric juice, duodenal juice and bile. The solids were separated, the aqueous phase was extracted with hexane, the hexane extract analyzed for PCDD/F. Additionally, the PCDD/F-content of the red slag was determined. Extraction efficiency was tested with three different digestive juice model mixtures and also tap water for comparision. The percentage of PCDD/F transferred from the red slag sample into the digestive juice mixture was defined as absorption availability. In our experiments, a maximum absorption availability of 2 % was found.  相似文献   

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