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1.
Concentrations of polychlorinated biphenyls (PCBs) have been measured in sewage sludge samples from 8 urban wastewater treatment plants in Beijing, China. The PCB congeners were analyzed by isotope dilution high resolution gas chromatography/high resolution mass spectrometry method. The concentration of PCBs ranged from 65.6 to 157 ng/g dry weight (dw), with a mean value of 101 ng/g dw. The dioxin-like PCB WHO-TEQs (World Health Organization-Toxic Equivalents) of the sludge were lower than 1 pg /g dw. Conse...  相似文献   

2.
采用同位素稀释质谱法,用高分辨率气相色谱-高分辨率质谱仪(HRGC-HRMS)对上海崇明农业土壤中12个共平面多氯联苯(co-PCBs)的含量进行了测定,并且对可能的来源进行了初步探讨。31个农业土壤中co-PCBs浓度范围为24.86~814.50 pg/g,平均值为92.65 pg/g,毒性当量浓度(I-TEQ)为0.032~0.486 pg/g,平均值为0.142 pg/g。经过比较,其浓度远远低于国内外污染土壤水平,和一般的农业土壤水平比较接近,认为该地区基本未受co-PCBs的污染。其中个别位点的毒性当量浓度较高,认为有必要对该地区可能的来源进行分析。主成分分析结果表明,崇明土壤co-PCBs可能来自市售Arcolor和各种燃烧,包括室内煤炭、木料燃烧以及固体或医疗废物燃烧的影响。作为生态岛屿建设的崇明,需要特别关注防止土壤中的co-PCBs进一步升高降低生态系统良性循环的完整性。  相似文献   

3.
The concentrations and distributions of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) in the whole blood and meat of eight typical edible animals (chicken, donkey, horse, cattle, rabbit, sheep, duck, and pig) were illustrated. Total concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and PCBs (on a basis of liquid volume) in animal bloods were 142-484 pg/L and 46-62 ng/L, respectively. Total concentrations of PCDD/Fs and PCBs (on a basis of dry weight (dw) and lipid weight (lw)) in animal meat samples were 0.47-1090 pg/g dw (0.47-4513 pg/g lw) and 7.2-23 ng/g dw (10-776 ng/g lw), respectively. TEQs for both PCDD/Fs and PCBs in animal blood and meat samples were (67 ± 27) pg/L and (5.3 ± 14) pg/g dw (24 ± 56 pg/g lw), respectively. Besides, the dietary intakes of PCDD/Fs and PCBs were also estimated. Chicken and pig contributed more TEQs than other animals. Chicken contributed the most (95%) with high toxicity, followed by pig (3.4%) with high consumption. The dietary intake of chicken might pose risks to consumers who prefer to eat chicken products, who should comprehensively consider the essential nutrients and contaminants in food during dietary intake.  相似文献   

4.
The impact of a typical municipal solid waste incinerator (MSWI) on polychlorinated biphenyl (PCB) concentrations in the surrounding soil was studied. Six stack gas samples were taken from the MSWI and 21 soil samples were collected from sampling sites between 300 and 1700 m from the MSWI stack. The total (∑PCB) concentrations of dioxin-like (dl) PCBs and indicator PCBs in the stack gas samples were between 3.41 and 34.3 ng/m3, and the corresponding toxic equivalents (TEQs) ranged from 4.45 to 66.9 pg WHO-TEQ/m3, with a mean of 28.6 pg WHO-TEQ/m3. A total of 2.43 g WHO-TEQ of PCBs per year was calculated to be released into the environment from MSWIs in China. The ∑PCB concentrations in the soil samples ranged from 28.0 to 264.4 pg/g, with mean and median values of 127.6 and 127.7 pg/g, respectively, while the TEQ values were between 0.020 and 0.18 pg WHO-TEQ/g, with mean and median values of 0.074 and 0.062 pg WHO-TEQ/g, respectively. Comparing this study with other studies performed around the world suggest that PCB emission from incinerators has a critical influence on PCB concentrations in the surrounding soil. An exponential function equation is proposed, which indicates a clear decline in ∑PCB concentrations with increasing distance from the stack. A contour map created using an ordinary kriging interpolation technique showed that a limited area (1250 m radius) from the stack was clearly influenced by PCB emission from the MSWI.  相似文献   

5.
卢双  张旭  裴晋  姚宏  于晓华 《中国环境科学》2016,36(9):2741-2748
采用气质联用仪(GC-MS)对黄河中下游流域18个国家控制断面处表层土壤(0~15cm)样品中的多氯联苯含量进行测定,分析其残留特征、可能的污染源和生态风险.结果表明,黄河中下游表层土壤中∑PCBs变化范围为0.43~39.83ng/g dw,均值为3.72ng/g,和其他地区研究结果相比,黄河中下游流域表层土壤中PCBs 含量水平较低.类二英类PCBs的毒性当量DL-TEQ变化范围为1.85~27.22pg/g dw,均值为15.24pg/g dw,远低于其他国家相应的限值,极少存在生态风险. PCB18、PCB33、PCB49、PCB44、PCB52的检出率和残留量均比较高,是黄河中下游流域表层土壤中的优势污染物.二氯联苯、三氯联苯和四氯联苯是主要的同族体,分别占总量的10.71%.13.48%、63.43%,说明黄河中下游流域表层土壤中主要是低氯联苯污染.主成分分析表明黄河中下游流域表层土壤中PCBs主要是来自Aorclor1242、1248、1254、1260系列PCBs产品和国产变压器油的混合污染源.  相似文献   

6.
多氯联苯(polychlorinated Biphenyls,简称PCBs)已成为全球性的重要污染物之一。实验确立了浸泡-超声提取、硫酸硅胶-去活化硅胶-硝酸银硅胶复合层析柱净化、毛细管柱气相色谱法测定植物样品中痕量多氯联苯的方法。对浙江台州地区典型污染点玉露洋村、横街、莄李王村三地的植物样品(卷心菜、南瓜)进行测定,结果显示台州典型污染区内卷心菜中PCBs的浓度范围在5.98~112.36 ng/g,南瓜叶中PCBs平均值达130.70 ng/g,茎中达59.12 ng/g,三地在总体上污染严重。PCBs同系物间的污染水平存在显著差异,二氯联苯残留量大,四氯、五氯、六氯联苯分布较广、残留较高,高氯联苯有少量存在。  相似文献   

7.
采用稳定同位素分析技术和气相色谱-高分辨质谱联用技术,测定了洞庭湖6种鱼组织的稳定氮同位素丰度值(δ15N值)和多氯联苯(PCBs)的含量,研究了鱼组织中PCBs分布特征及其与营养级的相关性.结果表明,∑PCBs115的浓度范围为0.04~9.77ng/g湿重,在鲤鱼性腺组织中最高.毒性当量为:0.0003~2.39pg/g湿重,在鳡鱼脂肪组织中最高.洞庭湖鱼中PCBs的含量处于较低水平.PCB28,52,95,99,101,105,110,118,138,153,155和209在所有组织中检出.Co-PCBs,Ind-PCBs和PCB209具有组织分布特异性.不同计量方式下,鱼组织中PCBs与δ15N值具有相关性的同类物不同.  相似文献   

8.
贵州红枫湖地区水稻土多氯联苯和有机氯农药的残留   总被引:27,自引:6,他引:21  
调查了红枫湖周边水稻土的7种多氯联苯(PCBs)和13种有机氯农药(OCPs)的含量分布.结果显示,DDTs及其代谢产物、HCHs的异构体、异狄氏剂、七氯等有机氯农药及PCB 28和PCB 52在所有样品中均被检出.与国内外污染区相比,PCBs含量较低.研究区土壤中污染物的组成结果类似,PCBs以3~5氯取代的同属物为主,农药以DDTs为主.剖面土壤中∑PCBs含量范围为8.9~55.9 ng/g,主要以3~5氯取代的PCBs为主,平均占PCBs总量的89%.∑DDTs含量为 4.7~42.6ng/g,以p,p′-DDE,p,p′-DDT为主.DDT/(DDD+DDE)的比率表明红枫湖地区水稻田中DDTs的降解速率不同,暗示其环境条件的差异.α-HCH/γ-HCH为0.28~0.90,表明红枫湖地区水稻田中HCHs在环境中残留时间很长,经历了光解和生物作用等变化.PCBs对TEQ的贡献较低,为0.06~0.51 pg/g.  相似文献   

9.
废弃电容器封存点及旧工业场地多氯联苯的污染特征   总被引:5,自引:4,他引:1  
研究了四川资阳机车厂废弃电力电容器封存点与旧工业场地土壤与降尘中28种多氯联苯(PCBs)的污染水平与组成特征.电容器封存山洞未封闭洞口处土壤中PCBs含量最高,28种PCBs的总含量(ΣPCBs)达227 502 ng.g-1,铸铁车间窗台降尘中也有高残留的PCBs,ΣPCBs在10μg.g-1以上,封存点和铸铁车间样品中PCBs单体含量之间均存在显著的正相关关系(P〈0.01).高污染样品中PCBs的同族体分布均以四氯代PCBs为最高,其次为三氯代PCBs和五氯代PCBs.与封存点土壤相比,铸铁车间样品中高氯代PCBs的贡献更大.12种类二英PCBs的毒性当量(TEQ)介于75.43~24 027 pg.g-1之间,远大于电子垃圾拆解区土壤,但普遍都以PCB126的毒性当量贡献占绝对优势.  相似文献   

10.
李素梅  朱琦  刘平  尚屹  田亚静  姚薇  朱维耀 《环境科学》2009,30(7):2093-2098
对国内某化工企业一系列对二氯苯样品和日本某企业对二氯苯样品的PCBs副产物的含量和生成机制进行了研究.在该企业对二氯苯样品检测到了62~781 ng/g的PCBs,WHO-TEQ最高达到了0.24 pg/g,在日本样品中PCBs总量也达到了881 ng/g,说明PCBs副产物在对二氯苯生产中是一个比较普遍的现象.在对二氯苯样品中,PCB31是主要的PCBs单体,最高占到了PCBs总量的98.5%.对二氯苯样品中都是TrCBs含量最高,其次是TeCBs和DiCBs以及PeCBs;而氯苯样品中则是MoCBs含量最高,占到了PCBs总量的73.5%.本研究还对各主要PCBs化合物的生成机制进行了探索,发现多氯苯缩合生成PCBs的过程受到多氯苯的浓度和氯对苯环的定位影响,并得到了试验的证实.  相似文献   

11.
Organochlorine pesticides(OCPs),polychlorinated biphenyls(PCBs),and polycyclic aromatic hydrocarbons(PAHs) were determined in nineteen surface sediment samples collected from Baiyangdian Lake and its inflowing river(Fuhe River) in North China.Total concentrations of OCPs,PCBs and PAHs in sediments ranged from 5.4 to 707.6 ng/g,2.3 to 197.8 ng/g,and 101.3 to 6360.5 ng/g,respectively.The levels of contaminants in Fuhe River were significantly higher than those in Baiyandian Lake.For hexachlorocyclohexane(HCHs) and dichlorodiphenytrichloroethanes(DDTs),α-HCH and p,p-DDT were predominant isomers;while for PCBs,PCB 28/31,PCB 40/103,PCB 60,PCB 101,and PCB 118 were predominant congeners.Possible sources derived from historical usage for OCPs and incomplete combustion fuel,wood,and coal and exhaustion of boats or cars for PAHs.Risk assessment of sediment indicated that sediments in Fuhe River were likely to pose potential biological adverse impact.  相似文献   

12.
A total of 198 agricultural soil samples were collected from Zhangjiagang and Changshu in Southern Jiangsu for analysis of 13 polychlorinated biphenyls (PCBs) in order to assess the levels of pollution, sources, area distribution, and potential risk for the environment. All methods were rigorously tested and an adequate quality control was ensured. Only one site had no PCBs residues, and the highest total PCBs concentration in the surface soils was 32.83 ng/g. The average concentration in all the soil samples was 4.13 ng/g, signaling low-level pollution. Tetra-, penta-, and hexa-chlorinated biphenyls were dominant species in soil samples, accounting for more than 75% of ∑PCBs in the soil samples. PCB118 was the most abundant congener in all the samples. The PCB118 was about 20% of ∑PCBs. The soil organic matter content showed only a weak correlation with the levels of all PCB congeners, in which a better correlation was noted for the more volatile lighter PCB congeners than for the heavier homologues. To a certain extent, the sources and land use seemed to influence the levels of PCBs.  相似文献   

13.
The concentration of polychlorinated biphenyls (PCBs) in the urban air of Dalian, China was monitored from November 2009 to October 2010 with active high-volume sampler and semipermeable membrane device (SPMD) passive sampler. The concentration of PCBs (particle + gas) ( ∑ PCBs) ranged from 18.6 to 91.0 pg/m 3 , with an average of 50.9 pg/m 3 , and the most abundant dioxin-like PCB (DL-PCBs) was PCB118. The WHO-TEQ values of DL-PCBs were 3.6-22.1 fg/m3 , with an average of 8.5 fg/m 3 , and PCB126 was the maximum contributor to ∑ TEQ. There was a much larger amount of PCBs in the gas phase than in the particulate phase. The dominant PCB components were lower and middle molecular weight PCBs. With increasing chlorination level, the concentration of the PCB congeners in the air decreased. The gas-particulate partitioning of PCBs was different for the four seasons. The gas- particulate partitioning coefficients (logK p ) vs. subcooled liquid vapor pressures (logP L 0 ) of PCBs had reasonable correlations for different sampling sites and seasons. The absorption mechanism contributed more to the gas-particulate partitioning process than adsorption. Correlation analysis of meteorological parameters with the concentration of PCBs was conducted using SPSS packages. The ambient temperature and atmospheric pressure were important factors influencing the concentration of PCBs in the air. The distribution pattern of the congeners of PCBs and the dominant contributors to DL-PCBs and TEQ in active samples and SPMDs passive samples were similar. SPMD mainly sequestrated gas phase PCBs.  相似文献   

14.
IntroductionContaminationofthemarineenvironmentassociatedwithorganochlorineshasreceivedincreasingattentionoverthelastthirtyyears.Particularattentionhasbeenfocusedonthecoastalzoneandestuaries ,especiallynearmetropolitanregion(Sericano ,1990 ) .ThePearlRiverestuarine ,rangefromDayaBayintheeasttoChangshanIslandsinthewest,supportslargepopulationsofmarineorganismsandextensivefisheriesintheSouthChina .Sincethe 1980s ,therehasbeenrapideconomicdevelopmentinthePearlRiverDeltaresultinginexcessivedi…  相似文献   

15.
采用高分辨率气相色谱-高分辨率质谱联用法分析位于青藏高原东缘的若尔盖高原牧场地表水和大气湿沉降中有机氯农药(OCPs)和多氯联苯(PCBs)异构体含量的季节分布特征,探讨持久性有机污染物(POPs)在边远清洁地区的地球化学行为.结果表明,若尔盖地区地表水中∑HCHs、∑DDTs、HCB、∑6PCBs平均浓度分别为0.90,1.36, 0.95,1.35ng/L.大气降水中OCPs和PCBs平均浓度分别为0.363,0.118ng/L,最大值出现在11月初冬的降雪样品中.异构体按平均浓度排序为HCB > PCB28 > p,p’-DDD > p,p’-DDE > α-HCH > γ-HCH.PCBs以PCB28和PCB52为主,除少量的PCB101外,其余高氯代PCB化合物都未在沉降样品中检出.∑HCHs、∑DDTs、∑PCBs的大气沉降通量分别为0.058~0.268,0.087~0.311,0.049~0.188ng/(m2·d).高海拔地区POPs大气沉降模式可分为“海拔梯度降水型”和“高原型”2类.类似于极地冷凝作用,高原型降雪中的POPs的沉积通量高于降雨沉降通量,但持久性较强的PCB138、PCB153和PCB180则缺失.这一结果验证了高空大气远程迁移和局地的高山冷凝效应的区别.  相似文献   

16.
渤海湾脉红螺中多氯联苯和多溴联苯醚的测定分析   总被引:4,自引:2,他引:2  
应用GC/HRMS对渤海湾脉红螺中的PCBs(多氯联苯)和PBDEs(多溴联苯醚)2类持久性有机污染物进行了测定分析.结果表明:雄性脉红螺中PCB(3~10氯代)的质量分数(10.1 ng/g,以干质量计)和PBDEs(BDE28、BDE47、BDE99、BDE100、BDE153、BDE154、BDE209)的质量分数(1.74 ng//g)均高于雌性脉红螺(分别为8.09和1.38 ng/g);雄性脉红螺中PCBs的WHO-TEQ(毒性当量,8.41 pg/g,以脂肪质量计)高于雌性脉红螺(4.34 pg/g),其中PCB118和PCB126的贡献率分别为13%和77%.脉红螺的不同组织中,性腺和消化腺中w(PCBs)和w(PBDEs)最高,肌肉组织中最低;主要同类物为PCB118、PCB101、PCB28、PCB138、PCB180、PCB52、PCB153和5-PCB以及BDE209.渤海湾脉红螺的消化腺可以作为PCBs和PBDEs的生物指示物.  相似文献   

17.
Concentrations of Polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/Fs) and polychlorinated biphenyls(PCBs) in soil samples from Tibetan Plateau were determined. The average concentration of total 2,3,7,8-PCDD/Fs was(2.30 ± 1.02) pg/g, and World Health Organization Toxicity Equivalency(WHO-TEQ) average concentration was(0.013 ± 0.010)pg WHO-TEQ/g. The average concentration of ∑PCBs(7 indicator PCB and 12 dioxin like-PCB congeners) was(16.2 ± 9.25) pg/g, and WHO-TEQ average concentration was 0.043 ±0.049 pg WHO-TEQ/g. Comparing to previous studies in similar environmental conditions,PCDD/Fs and PCBs in this study showed a relatively lower concentration. The altitude dependences of PCDD/Fs and PCBs were also studied. Total organic carbon(TOC) normalized concentrations presented a quadratic relation with the altitudes, and an inflection could be found on the parabola of the total concentrations and some congeners of high concentration.The concentrations decreased with altitudes below about 4500 m above sea level(a.s.l.), while they increased with altitudes above it. These phenomena indicate that cold condensation of PCDD/Fs and PCBs would happen above 4500 m a.s.l, on the Tibetan Plateau.  相似文献   

18.
Persistent organochlorine compounds, including hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs) and polychlorinated biphenyls (PCBs) were analyzed in surface water and sediments from Baiyangdian Lake, North China. Total concentrations of HCHs, DDTs and PCBs in surface water were in the range of 3.13-10.60, 4.05-20.59 and 19.46-131.62 ng/L, respectively, and total concentrations of HCHs, DDTs and PCBs in sediments were 1.75-5.70, 0.91-6.48 and 5.96-29.61 ng/g dry weight, respectively. Among the groups of HCHs (sum of α-HCH, β-HCH, γ-HCH and δ-HCH) and DDTs (sum of DDT, DDD and DDE), the predominance of β-HCH, DDE and DDD in water and sediment samples was clearly observed. This observation suggested that β-HCH was resistant to biodegradation and the DDTs had been transformed to its metabolites, DDE and DDD. For PCBs, penta-, hexa- and hepta-chlorinated congeners were the most abundant compounds in the both phases. Furthermore, the partitioning of chlorinated compounds between sediment and water was investigated to understand their transport and fates in aquatic ecosystems. The results indicated that average logs of organic carbon-normalized sediment-water partition coefficients (logKoc') for OCPs varied between 3.20 and 5.53, and for PCBs, logKoc' values ranged from 3.19 to 5.57. The observed logKoc' was lower than their equilibrium logKoc predicted from linear model, which may be attributed to the solubility enhancement effect of colloidal matter in water phase and the disequilibrium between sediment and water.  相似文献   

19.
长江三角洲典型地区农田土壤多氯联苯空间分布特征   总被引:9,自引:1,他引:8  
滕应  郑茂坤  骆永明  高军  李振高  吴龙华 《环境科学》2008,29(12):3477-3482
在面积为27 km2 的长江三角洲某典型污染地区用GPS定位系统布设了191个取样点,采用GC-ECD法测定了表层农田土壤16种多氯联苯组分及含量.统计结果表明,该典型区农田土壤16种多氯联苯总量变化范围是0.01~484.5 ng/g, 平均值是35.52 ng/g,而且以三氯和四氯联苯为主(占55.7%),同时也含有一定比例的五氯和六氯联苯(占44.3%).空间分析发现,该区农田土壤中PCBs总量及其各同系物在所研究的尺度上存在较强的空间自相关格局,其PCBs的空间分布模式主要可能受到一些较为分散的人为因素影响,应重点对当地这些人为活动排污行业进行整治,以消除污染来源.  相似文献   

20.
哈尔滨市土壤中PCBs的污染现状研究   总被引:1,自引:0,他引:1  
采用GC/MS法对哈尔滨市18个表层土壤及1个深层土壤中PCBs的浓度进行了测定,并讨论了PCBs在土壤中的分布特征及同族体的组成情况。结果表明,该市表层土壤中∑PCBs浓度分布在0.025-1.795ng/g之间,平均值为0.545ng/g,深层土壤中未能检测到目标物,土样中共有18种同系物有不同程度的检出,主要以五氡联苯为主,其中工业区的土壤样品中∑PCBs含量最高。  相似文献   

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