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1.
2009年7月在江苏省南部城市苏州、无锡和南通采集了58个城市道路灰尘样品,使用气相色谱质谱法测定了样品中的8种多溴联苯醚(PBDEs)和32种多氯联苯(PCBs).结果表明,样品中Σ8PBDEs含量范围为4.21~1 471μg·kg-1,Σ32PCBs含量范围为ND~14.1μg·kg-1,PBDEs的含量远远高于PCBs.和其他地区城市土壤样品比较,城市道路灰尘中的PBDEs含量较高,来自燃料燃烧过程和汽车尾气产生的PBDEs不容忽视.城市工业区和中心区样品中PBDEs和PCBs的含量水平没有显著性差异,而高于景观区.研究发现,在城市工业区存在PCBs非故意排放源.PBDEs同族体单体相对含量分析表明,BDE209是样品中检测出的最主要的PBDEs单体,占Σ8PBDEs含量的96.7%(64.1%~99.8%).样品中的PCBs同族体主要为四氯代PCBs和六氯代PCBs,道路灰尘中PCBs同族体的分布模式与PCBs产品和其他环境介质存在一定差异.  相似文献   

2.
 为了解PCBs在生态系统中的分布,利用毛细管气相色谱对受PCBs污染地区的土壤、底泥进行实际环境样品的调查。在底泥和土壤样品中测定近50个同属物的含量,并对其分市规律进行了探讨。指出在实际环境样品中PCBs的同属物分布和工业产品有明显不同。通过不同深度底泥样品测定,证明PCBs在底泥中的渗透作用较弱。  相似文献   

3.
为精准揭示近年来珠江口及邻近海域表层沉积物多氯联苯(PCBs)污染状况,于2020年在包括珠江八大口门在内的邻近海域布设27个站位采集表层海洋沉积物样品,采用同位素稀释内标HRGC/HRMS法测定包括一氯至十氯联苯的37种单体及其各氯代同系物含量,刻画其空间分布特征并分析其主要来源.结果表明,1)27个站位表层沉积物样品中PCBs均有检出,37种PCBs单体可充分反映样品中PCBs的污染,∑37PCBs含量为0.024~5.11ng/g,低于国内外主要近岸海域污染水平;2)主要污染集中在珠海沿岸海域和虎门出海口水域,且表现出距离岸边越近,污染浓度越高的受陆域影响空间分布特点;3)37个单体中PCB-11的检出频率和检出浓度均最高,检出浓度远高于传统关注的marker-PCBs总和,是样品中PCBs的主要污染贡献者;4)结合主成分分析及同系物组成分析研究区域表层沉积物PCB污染主要来源发现,只有珠江出海口东岸沿线海域部分表层沉积物PCBs的污染可能与PCB工业商品相关,珠江口及邻近海域表层沉积物中的PCBs可能主要来源于当地联苯胺黄颜料的生产或使用.本研究珠江邻近海...  相似文献   

4.
为了考察珠江三角洲地区大气和土壤中多氯联苯(PCBs)残留现状,于2012年在珠江三角洲地区采集了空气和土壤样品,并利用GC-MS进行PCBs分析测定。结果表明,大气中Σ24PCBs的总浓度为240~2 258 pg/m3,平均为1 243 pg/m3,且PCBs主要存在于气相中,占24种PCBs总浓度的90%以上,单体分布主要以三氯~五氯联苯为主。自2001年以来珠江三角洲地区大气中PCBs浓度有小幅波动,说明部分地区有PCBs源释放的可能。土壤中24种PCBs的总浓度为ND~20.68 ng/g,平均为3.77 ng/g。三氯联苯是土壤中PCBs的主要同类物,平均占土壤中24种PCBs总浓度的45%,其次是四氯联苯,平均占19%。部分地点低氯代PCBs比例下降,高氯代比例升高。  相似文献   

5.
变压器油中多氯联苯的测定   总被引:10,自引:3,他引:10  
着重研究变压器油中多氯联苯(PCBs)测定的样品前处理技术,确定了变压器油中PCBs分离的最佳条件,并应用GC/ECD测定PCBs总量.回收率在86%-110%之间,变异系数1%-3%.此外,采用GC/MS联用方法对变压器油中PCBs进行了定性分析.  相似文献   

6.
海河河口表层沉积物中PCBs和OCPs的源解析   总被引:4,自引:2,他引:2       下载免费PDF全文
王泰  黄俊  余刚 《中国环境科学》2009,29(7):722-726
采集海河河口表层沉积物样品,测定了其中12种多氯联苯(PCBs)和20种有机氯农药(OCPs)的浓度,运用主成分分析-多元线性回归法(PCA-MLR)解析该区域沉积物中PCBs和OCPs的来源,并定量计算了各污染源的贡献量.结果表明,海河沉积物中PCBs的特征源为非故意产生和大气输送2类,基于多元线性回归法的贡献率分别为55%和45%,对PCBs总量的贡献量均值为6.94,9.42ng/g;OCPs的特征源为历史残留和新的输入2类,贡献率分别为13%和87%,对OCPs总量的贡献量均值为21.18,171.97ng/g.海河河口沉积物中POPs的源贡献与该区域的工业生产有关,改善工业结构和妥善处理历史遗留的生产废物是控制海河河口沉积物中POPs的有效途径.  相似文献   

7.
动物性食品中PCBs的生物有效性及人体日暴露评估   总被引:2,自引:0,他引:2       下载免费PDF全文
通过测定上海市售动物性食品中PCBs的浓度和生物有效性,评估该地区PCBs的人体日暴露量.结果表明,不同种类食品中PCBs的浓度在未检出~3734.3pg/g(湿重)之间,3~6氯PCBs为主要同系物.鱼类中PCBs浓度高于畜类、禽类和软体类.鱼类PCBs的浓度水平遵循以下两规律:海水鱼>淡水鱼;肉食性鱼>杂食性鱼>草食性鱼.采用模拟人体胃肠消化过程测得PCBs的生物有效性,由于食品中脂肪含量与PCBs的生物有效性具有显著的线性关系,故可用于计算样品中PCBs的生物有效性.该地区居民每天通过动物性食品摄入的PCBs量为24439.3pg/d,以PCBs的生物有效性计量为5034.5pg/d.对不同暴露源(包括灰尘和大气颗粒物)的分析表明,鱼类是PCBs人体暴露的主要贡献者,约占人体PCBs日暴露的60%.  相似文献   

8.
王莎莎  高丽荣  田益玲  朱帅  张芹 《环境科学》2014,35(6):2281-2286
多氯联苯(PCBs)具有高毒性和生物蓄积性,是列入公约优先控制的持久性有机污染物之一.多氯联苯在水生食物链中蓄积,同时人类食用鱼肉会对人体健康产生一定影响.近渤海地区具有焚烧、钢铁冶炼及水泥等PCBs非故意潜在排放源,而对此区域PCBs产生的环境污染及造成的人体健康效应的研究较少.本研究利用高分辨气相色谱/高分辨质谱(HRGC/HRMS)首次对近渤海地区10种不同鱼类中的二噁英类多氯联苯(dl-PCBs)和指示性PCBs进行了分析.12种dl-PCBs的含量(以湿重计)为28.9~1067.6 pg·g-1,其中PCB-118和PCB-105是主要贡献单体,贡献率分别是41%~56%和15%~21%.指示性PCBs的浓度范围是185.5~8371.7 pg·g-1,其中PCB-153和PCB-138是主要的贡献单体,贡献率分别是27%和22%.与国内外其他海域的研究相比,近渤海区海水鱼中PCBs残留量处于较低水平,对人体产生健康风险比较小.  相似文献   

9.
长江口九段沙水域环境及生物体内多氯联苯分布   总被引:6,自引:1,他引:5  
对长江13九段沙湿地自然保护区的滩涂水样、泥样以及水生生物体内的多氯联苯进行GC-MS检测,研究多氯联苯各单体在不同环境介质及生物体中的分布状况.结果表明:水样、泥样中的多氯联苯检出率为100%,其中四氯联苯(PCB52)含量最高;与其他河13地区相比,九段沙水域水体中多氯联苯(PCBs)含量处于中等水平,ρ(PCBs)为23~95 ng/L;滩涂泥样多氯联苯含量则较低,w(PCBs)为1.77~4.51 ng/g;该水域水生生物多氯联苯检出率为100%,w(PCBs)为0.12~9.40μg/kg,低于国家标准限量;软体动物、甲壳类以及鱼类检出单体均以高氯类PCBll8和PCB138为主,而非环境中含量较高的PCB52,反映了水生生物对于高氯类多氯联苯富集能力强于低氯类多氯联苯.  相似文献   

10.
为了解水库上覆水环境对底泥释磷强度的影响,确定底泥释磷强度与环境要素的定量线性关系,阐明不同水环境条件下底泥释磷机理。2014年8月对大河口水库采集底泥样品,进行了4因素(水温、pH、水动力、溶解氧)5水平底泥释磷室内模拟试验。结果表明:(1)温度升高有利于底泥磷的释放,25℃条件下底泥平均释磷强度为30.04 mg/m2,是5℃条件下释磷强度9.01 mg/m~2的3.3倍。(2)强酸碱条件均有利于底泥磷释放,中性条件下底泥释磷强度最小,试验期内强碱条件下(pH=9.5)底泥释磷强度分别是强酸条件(pH=5.5)和中性条件(pH=7.0)释磷强度的1.1倍和1.9倍。(3)增加扰动可加速泥水界面交换,促进底泥磷释放。高强度扰动下底泥最大释磷强度为25.18 mg/m~2,是静置条件下的3.8倍。(4)随溶解氧浓度增大底泥释磷强度呈下降趋势。DO为6.5 mg/L以上时,底泥释磷呈现"负释放"状态。(5)底泥释磷强度与温度、pH、水动力环境因素二次函数曲线拟合最优,与溶解氧三次函数曲线拟合最优。  相似文献   

11.
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   

12.
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   

13.
典型钢铁厂周边土壤中多氯联苯分布特征研究   总被引:3,自引:0,他引:3       下载免费PDF全文
钢铁厂中各工业热过程车间都会产生污染物并对周边环境造成危害,本文以迁安市钢铁厂周边土壤为研究对象,对该市内及钢铁厂周边土壤样品进行采集,采用同位素稀释高分辨气相色谱-高分辨质谱方法(HRGC/HRMS)测定了多氯联苯(PCBs)的含量,研究了PCBs的同类物分布特征.结果发现,市内及钢铁厂周边土壤样品中dl-PCBs的总含量为4.77~462.04 pg·g~(-1),WHO-TEQ(Toxic Equivalent Quantity)即毒性当量值为0.03~1.34 pg·g~(-1).由此可以看出,该市及钢铁厂周边环境土壤受到了PCBs等有毒污染物的影响.大部分土壤样品的同类物分布特征相似;PCB~(-1)18对土壤dl-PCBs含量贡献率最大,贡献率为34%.PCB~(-1)01对土壤指示性PCBs含量贡献率最大,贡献率为42.5%.同时,通过对样品中同类物分布可以看出,低氯代的同类物(Tr CBs~Hx CBs)的含量要远高于高氯代同类物(Hp CBs~De CBs).  相似文献   

14.
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   

15.
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   

16.
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   

17.
采用气质联用仪(GC-MS)对长江流域13个干流断面及18个支流断面处沿岸表层土壤样品中的多氯联苯(PCBs)进行测定,分析其残留特征、污染来源和健康风险.结果表明,长江流域表层土中ΣPCBs的含量范围为:1.05~50.11ng/g dw,平均值为5.71ng/g dw,含量处于较低污染水平.干流的PCBs含量从上游到下游呈现逐渐增大的趋势,且PCBs在宜昌、岳阳、武汉、重庆等二三线城市总含量较高.PCB 17,PCB 18,PCB 44,PCB 74,PCB 87的检出率较高,三氯联苯、四氯联苯是主要的同系物,表明长江流域表层土壤主要以低氯联苯污染为主.主成分分析表明研究区域PCBs主要来自于1号国产变压器油、Aorclor 1242、1248、大气沉降及地表径流的混合污染源;对长江流域表层土壤健康风险评价表明,PCBs存在较小健康风险,呼吸摄入潜在风险低于经口摄入及皮肤接触.  相似文献   

18.
Although polychlorinated biphenyls(PCBs) are globally recognized pollutant, an understanding of their resources as by-products in chemical industry is poorly investigated. This paper presents data from a study that was conducted in order to determine the extent of PCBs in 1,4-dichlorobenzene(p-DCB) mothballs. Total PCBs and dioxin-like PCBs were detected in five mothball samples. Total PCB concentrations ranged from 328 ng/g to 1798 ng/g, while the levels of WHO-TEQ were between 0.16 pg/g and 13 pg/g. Mean concentrations of total PCBs and WHO-TEQ in the samples were 724 ng/g and 3.2 pg/g, respectively. The highest level of PCB congeners was that of trichlorinated biphenyls(537 ng/g), which maybe due to the relatively low chlorination in the process of p-DCB production. A mechanism of the formation of PCBs from polychlorinated benzene in the presence of chlorine is also suggested. The results suggested that re-estimation on the risk of p-DCB products, especially the products for daily use such as mothballs, is expected.  相似文献   

19.
The Yellow River Delta (YRD) is a typical agricultural and petrochemical industrial area of China. To assess the current status of soil dichlorodiphenyltrichloroethane (DDT) and polychlorinated biphenyls (PCB) residues, topsoil samples (0-15 cm) (n = 82) were collected in Bincheng District, at the geographic center of the YRD. The total concentrations of six DDT homologues were within 3.3-3819 μg/kg, with a mean concentration of 191 μg/kg, showing significant increase along urban-rural gradient. Soil concentrations of seven indicator PCBs in the area ranged from non-detectable to 87.0 μg/kg, dominated by heavily chlorinated PCBs (PCB-101 and -118). Soil PCBs concentrations were significantly greater in urban than suburban and rural areas. Principal component and multiple linear regression analysis suggest that 86.4% of soil DDTs originate from past DDT usage, and 13.6% originate from dicofol application. Soil PCBs most likely originate from the petrochemical industry (77.1%), municipal solid waste disposal (16.5%), local commercial PCB homologues usage (5.2%), and long-range atmospheric deposition (1.2%). In general, soil DDTs pollution was classified as low level, and mean PCBs concentrations were below the severe contamination classification range. Because PCB-118 is a dioxin-like congener, monitoring and remediation is advised to assess and reduce negative environmental and human health effects from soil DDTs and dioxin-like congeners in the study area.  相似文献   

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