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171.
Polybrominated diphenyl ethers (PBDEs) have been reported in air, surface waters, suspended sediments, soil, sediment, fish, marine mammals, and bird eggs throughout Canada, from the St. Lawrence Estuary to the Strait of Georgia and the northernmost reaches of the Canadian Arctic. Canadian scientists have detected the presence of PBDEs in breast milk in every Canadian province. In fact, recent data on temporal trends strongly suggests that the concentrations of PBDEs are on the rise in the Canadian environment. These findings are similar to those reported in other nordic countries, and have prompted several countries to implement environmental monitoring programs. Among the key challenges currently facing Canada and other countries concerns how best to measure these chemicals in different matrices. In this paper, several analytical methods cited in the scientific literature for determining PBDE concentrations in different abiotic and biological matrices are reviewed. The critical criteria required for accurate determination of PBDEs in complex environmental matrices are discussed, including instrument sensitivity, reliability, potential interference's and the need for specialized instrumentation for the determination of compounds up to 975 Daltons. While a single analytical method that meets these and other criteria has not yet been perfected by scientists, GC/HRMS-based methods amenable to isotope dilution techniques warrant further refinement, and likely represent the best tools for future environmental monitoring programs.  相似文献   
172.
沉积物中溴化联苯醚的分析方法和污染特征研究   总被引:1,自引:1,他引:1  
详细讨论了沉积物中溴化联苯醚的提取净化、仪器测定、定量方法和质量控制。总结了国内外沉积物中PBDEs的污染现状与特征。最后根据我国的国情,对PBDEs的研究重点和方向提出建议。  相似文献   
173.
分别在典型电子垃圾拆解区(E)和其上风向参考点(S)采集了大气颗粒相和气相样品,以研究该区域大气中PBDEs的浓度水平、污染特征和气/固分布特点.分析过程中运用气相色谱-质谱联用仪,负化学离子源(GC-NCI-MS)检测了11种PBDEs.结果表明,电子垃圾拆解造成了比较严重的PBDEs污染,三溴~十溴联苯醚的浓度范围为51.1~2685 pg·m-3(平均值830 pg·m-3),而对照区由于制衣行业的影响也造成了一定程度的PBDEs污染,三溴~十溴联苯醚的浓度范围为1.00~98.9 pg·m-3(平均值28.7 pg·m-3).在气/固分布的研究中发现,不同的PBDEs在气相和颗粒相的分布比例相差很大,从低溴至高溴PBDEs在气相中的比例呈降低趋势,而在颗粒相中的比例呈上升趋势.电子垃圾拆解区以五溴-联苯醚污染为主,占∑11PBDEs总量的54.3%;而十溴-联苯醚污染次之,占∑11PBDEs总量的23.8%,该污染特征进一步证实了该地区电子垃圾的来源,不仅来自亚洲国家,而且还来自欧美等国家.  相似文献   
174.
为评估杭州市典型室内公共场所空气中多溴联苯醚(PBDEs)的污染现状,2016年5~8月和9~12月期间,采用空气被动采样技术(PUF-PAS)在17家室内公共场所总计采集54个空气样品,经样品预处理和GC-ECD分析后,结果表明,5类环境空气样品中∑14PBDEs浓度均值大小依次为网咖(2470.43pg/m3)>建材市场(1119.87pg/m3)>电子市场(660.84pg/m3)>商场(478.37pg/m3)>图书城(182.18pg/m3).最主要的特征单体均为BDE-209,占总量的36.79%~56.21%,BDE-47、BDE-99、BDE-153、BDE-183也是PBDEs在空气中较主要的同系物,其最高浓度分别占7.77%,7.56%,6.32%和7.73%.评估PBDEs人群暴露水平的结果表明,网咖内暴露水平最高,图书城则为最低,其浓度分别为570.10和44.79pg/(kg×d).室内空气中,对人群PBDEs总摄入量贡献最高的特征单体是BDE-209,平均水平为18.44~323.70pg/(kg×d),最低的则为BDE-183,平均水平为1.75~20.05pg/(kg×d),目前杭州市各典型室内公共场所PBDEs人群暴露水平相比美国环境保护署(EPA)提出的参考剂量较低.  相似文献   
175.
多溴联苯醚在电子废弃物拆卸地沉积物中的垂直分布   总被引:4,自引:3,他引:1  
陈社军  田密  罗勇  林镇  罗孝俊  麦碧娴 《环境科学》2010,31(12):3088-3092
采用气相色谱质谱联用仪对采自清远电子废弃物拆卸地水库钻孔沉积物中的多溴联苯(polybrominated diphenyl ethers,PBDEs)进行了分析,调查其在沉积物中的垂直分布.结果表明,PBDEs在所有的样品中均检出,含量为0.43~141 ng/g,平均为9.26 ng/g.PBDEs在下层(16 cm以下)沉积物中含量较低、变化很小(0.43~2.30 ng/g),但在上层沉积物中含量明显增加(2.90~141 ng/g),反映了当地电子废弃物拆卸活动的影响;3种工业源的PBDEs,即五溴、八溴和十溴PBDEs,表现出相似的垂向分布趋势,说明其来源的一致性.其中,十溴PBDEs是最主要的PBDEs,平均占所有PBDEs的79.6%,其次是五溴PBDEs(14.7%),而八溴PBDEs所占比例最低(5.69%).3种PBDEs的组成模式显示,它们与相应的工业品PBDEs组成都有一定差异,可能因其降解行为不同所致.一些PBDE的同族体组成在沉积钻孔的垂直变化也进一步说明高溴代PBDE在沉积物的埋藏期间可能发生了降解,虽然还需要进一步研究证实.  相似文献   
176.
Polybrominated diphenyl ethers (PBDEs) as ubiquitous persistent organic pollutants have attracted much attention in recent years. Exposure to PBDEs could induce a high health risk for children. The aim of this study was to investigate the PBDEs exposure of children (9–12 years) from Taizhou, China. Fifty-eight blood samples were collected in one school in a mountainous area in Taizhou. The concentrations of Σ9PBDEs (sum of BDE-28, -47, -99, -100, -153, -154, -183, -197 and -209) ranged from 2.66 to 33.9 ng/g lipid wet (lw) with a median of 7.22 ng/g lw. These concentrations were lower than those of children in USA, but close to European and Asian general population levels. The results showed that children in Taizhou countryside were at a low level of PBDEs exposure. The predominant congener was BDE-209, followed by BDE-28, -47, -197 and -153. High abundance of BDE-209 was consistent with the pollution background of PBDEs in China characterized by high brominated congeners as main pollutants.  相似文献   
177.
用GC-NCI-MS分析法测定了路桥河流表层沉积物中41种多溴二苯醚同类物的含量. 目的是了解该地区沉积物中PBDEs的污染水平、空间分布特征和来源. 结果表明,所有沉积物样品中40PBDEs(不包括BDE209)的含量为0.177~161 ng·g-1,平均值为22.5 ng·g-1, BDE209的含量为0.36~958 ng·g-1,平均值为148 ng·g-1. 同族体组成特征表明多数样品中十溴二苯醚(BDE209)是最主要的同族体,占38.4%~96.0%, 平均值为74.4%,九溴PBDEs和七溴PBDEs次之, 分别占3.3%~25.8%和0.01%~14.1%. PBDEs同类物之间呈显著性相关,表明大多数PBDEs同类物有相似的输入途径.同族体组成和聚类分析表明,所有采样点均受到deca-BDE工业品的污染,另有一些采样点除受到deca-BDE工业品的污染外, octa-BDE工业品也有一定的贡献. 与国内外其它研究相比,研究区域内沉积物中的PBDEs污染处于中低水平,但个别样点受点源污染影响较大,值得关注.  相似文献   
178.
This pilot study documented the occurrence and levels of brominated flame retardants in the tissues of farmed and wild salmon in southern Chile. Samples of Coho salmon and rainbow trout were obtained from fish farms, rivers and lakes in the Patagonia in Aysen Region, Chile. The samples were analyzed by Gas Chromatography Negative Chemical Ionization Mass Spectrometry for the different polybrominated diphenyl ether (PBDE) congeners. Contaminants were observed in all the samples, and the congeners BDE 17, 28, 47 and 66 were observed in all both farmed and wild samples. The concentrations were higher in the farmed Coho salmon, presenting significant differences with wild salmon. The levels reached 182 pg/g wet weight (ww) vs. 120 ww. In the case of the rainbow trout, the concentrations were lower, although the congener profile was quite similar. The levels reached an average of 100 pg/g ww in the farmed fish versus 110 pg/g ww in wild fish, and no significant difference was observed between the species. In both species, the congener with the highest concentration was BDE 47. Based on this information, the BDE flow was estimated for commerce, which is a form of pollutant transport not usually considered in POP pollution studies. A preliminary estimation indicated that the quantity of PBDEs mobilized by commerce was in the order of kg, and in the case of Chile might reach almost 1 kg.  相似文献   
179.
An indirect competitive fluorescence immunoassay using a DNA/dye conjugate as antibody multiple labels was developed on 96-well plates for the identification and quantification of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) in aqueous samples. A hapten, 2,4,2′-tribromodiphenyl ether-4′-aldehyde, was synthesized, and was conjugated to bovine serum albumin to form a coating antigen. Specific recognition of the antigen by anti-PBDE antiserum was confirmed by a surface plasmon resonance measurement. In the immunoassay, the coating antigen was adsorbed on a 96-well plate first, and a sample, antiserum and biotinylated goat anti-rabbit secondary antibody were then added and reacted sequentially. A biotinylated, double-stranded DNA with 219 base pairs was attached to the secondary antibody by using streptavidin as a molecular bridge. In situ multiple labeling of the antibody was accomplished after addition of a DNA-binding fluorescent dye, SYBR Green I. The working range of the immunoassay for the BDE-47 standard was 3.1-390 μg/L, with an IC50 value of 15.6 μg/L. The calculated LOD of the immunoassay is 0.73 μg/L. The immunoassay demonstrated relatively high selectivity for BDE-47, showing very low cross-reactivity (< 3%) with BDE-15, BDE-153 and BDE-209. With a spiked river water sample containing 50 μup g/L BDE-47, quantification by the immunoassay was 41.9 μg/L, which compared well with the standard GC-ECD method (45.7 μg/L). The developed immunoassay provides a rapid screening tool for polybrominated diphenyl ethers in environmental samples.  相似文献   
180.
采用大孔树脂D001交换吸附Pd2+、Fe2+并在厌氧条件下以硼氢化钠溶液还原吸附的钯铁离子制备成负载纳米Pd/Fe双金属树脂。利用该树脂对2,2',4,4'-四溴联苯醚(BDE-47)进行脱溴反应,探讨了该法的可行性和特性。结果表明:当大孔树脂D001、氯化钯、硫酸亚铁用量分别为0.75 g、2μg和0.2 g时所制备的双金属树脂脱溴水-乙醇溶液中的BDE-47效果最佳,反应遵循准一级动力学,速率常数k约为0.161 d-1,半减期为1.21 d。负载Pd/Fe的D001连续3次脱溴反应都有较好的效果,水-乙醇溶液中超过90%以上的BDE-47在反应6 d后被降解。负载Pd/Fe双金属的树脂可以重复活化再生,但再生2次后其脱溴效率变差,反应6 d只有47.3%的BDE-47被降解。用气相色谱-质谱联用仪和离子色谱仪跟踪Pd/Fe双金属树脂脱溴BDE-47反应,可知产物包括溴离子、三溴联苯醚、二溴联苯醚、一溴联苯醚和联苯醚。  相似文献   
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