工业热过程中无意产生的持久性有机污染物生成机理

持久性有机污染物(persistent organic pollutants,POPs)可在工业热过程中无意生成和被排放,而探究其生成机理是发展源头减排技术的基础.本文在梳理文献的基础上,发现二(噁)英的生成理论有了一些新的突破.关于氯酚和氯苯等前驱体在热过程中生成自由基中间体的研究,能够从分子层面上揭示二(噁)英的生...     

新型持久性有机污染物分析方法研究进展

多溴联苯醚、多溴联苯、全氟辛基羧酸/磺酸、十氯酮和溴代二(口恶)英等属于"斯德哥尔摩公约"2009年新增列和潜在的持久性有机污染物,近年来受到环境研究者的广泛关注.其在环境中的残留特征、污染来源、演变趋势、迁移传输、生物累积和毒理效应方面的研究依赖于分析技术的发展.多溴联苯醚和多溴联苯与传统持久性有机污染物具有类似的理化性质,采样和分析测定过程同有机氯农药和多氯联苯相近,可使用索氏提取、自动索氏提取、超声萃取、微波辅助萃取、压力溶剂萃取等多种提取方法,酸洗、多层复合层析柱和凝胶渗透色谱是最常用的净化手段,分析时采用GC/MS-EI或GC/MS-NCI对指示性单体进行定性定量.由于环境背景中的残留很低,使用高分辨质谱和串联质谱可降低方法检出限.对于水环境和沉积物中的全氟烷基羧酸、磺酸及其盐,目前主要采用固相萃取HPLC/MS/MS测定.亲水亲油平衡的萃取柱对全氟辛基羧酸和磺酸有良好的回收,弱阴离子交换萃取柱对短链和长链全氟烷基羧酸和磺酸都有满意的回收.十氯酮有一定极性,采用含有丙酮的萃取体系具有较高的回收率,GC/ECD和GC/MS分析时对色谱系统的清洁性有较高的要求,否则容易导致色谱峰拖尾影响定性和定量.溴代二(口恶)英与二(口恶)英的分析技术路线类似,需要更严格的净化过程分离多溴联苯醚,并在分析时控制热脱溴.此外,方法的应用还依靠溴代二(口恶)英标准物质的完善.     

气相色谱-质谱联用测定艾叶中持久性有机污染物

本文建立了气相色谱-质谱(GC-MS)联用测定艾叶中持久性有机污染物的分析方法。样品以正己烷和丙酮为提取剂,经提取液浓H2SO4和硅胶柱净化后,通过GC-MS联用测定19种有机氯农药和多氯联苯残留。结果表明,在25、50、100ng/g添加水平下平均回收率分别为71.0%~93.6%、79.7%~105.9%、85.1%~108.7%,相对标准偏差(RSD)分别为2.4%~11.6%、1.1%~8.6%、0.9%~7.5%。使用该方法分析不同批次的艾叶发现主要残留物为有机氯农药,其次是低氯取代的多氯联苯。方法简便高效,精密度好,可用于艾叶中持久性有机氯污染物的分析。     

持久性有机污染物研究进展

持久性有机污染物(Persistent Organic Pollutants,POPs)是指在环境中难降解、高脂溶性、可以在食物链中富集,能够在大气中通过蒸发-冷凝作用远距离传输而影响到区域乃至全球环境的一类半挥发性毒性很高的污染物.面对POPs对人类健康和生态环境的巨大威胁,国际社会达成共识,在全球范围内采取协调一致的行动.2004年5月17日《关于持久性有机污染物的斯德哥尔摩公约》正式生效,目前已有包括我国在内的178个国家加入了该公约.当前纳入公约控制的POPs已有22种.此外,短链氯化石蜡、六     

全二维气相色谱分析持久性有机污染物的应用进展

持久性有机污染物（POPs）组分复杂,在自然界中超痕量存在,其分离分析十分困难。全二维气相色谱（GC×GC）作为一种新型色谱技术,与传统的一维气相色谱相比,具有峰容量大、分辨率和灵敏度高等优势,越来越广泛地应用于环境有机污染物的分析。该文综述了近十年来全二维气相色谱在持久性有机污染物分析中的应用进展,主要包括全二维气相色谱在解决一些复杂POPs定性定量分析难题方面的应用,如二恶英、毒杀芬和短链氯化石蜡等;概述了全二维气相色谱对多种POPs同时定性定量分析的应用进展;讨论了全二维气相色谱在非目标有机污染物筛查分析中的应用,并对发展趋势及相关应用前景进行了总结展望。     

有机污染物的持久性评价方法研究进展

持久性有机污染物(POPs)具有持久性、生物蓄积性和高毒性等特点,对人类生存和发展已构成了严重威胁。本文对近年来有关POPs持久性的3种主要量化评价方法的研究进展进行了综述。其中,QSAR/QSPR方法主要以分子结构来推测有机物的理化性质,进而预测总持久性和长距离迁移能力;环境多介质模型方法根据物质在各种环境介质中的分配和反应性来评价物质的持久性;基于化学反应常数的评价方法是通过模拟和简化自然界的各种化学反应,尝试利用测得的反应常数比较物质的持久性。各种方法得到的物质持久性的评价和排序不尽相同,因而仍需要更深入广泛的研究,以建立统一的有机物持久性量化评价的标准体系。     

持久性有机污染物的分析检测研究进展

持久性有机污染物(POPs)可以通过各种环境介质(大气、水、生物体等)长距离迁移并长期存在于环境中,具有生物富集性、毒性、致畸、致癌性,对人类健康和环境具有严重的危害.用于此类物质的分析方法很多,主要可分为仪器联用分析方法和快速分析方法,如:色谱-质谱分析、光谱分析、生物分析、光/电分析、传感分析等.这些方法各有优缺点,互为补充.本文将按照分析方法,重点介绍2000年至今在POPs分析技术上的最新进展.     

手性持久性有机污染物的环境界面过程及生态安全研究进展

随着越来越多分子中含有手性结构的持久性有机污染物(POPs)进入环境介质,对其环境界面过程及生态安全的研究已成为环境科学领域的一个热点.目前,有关手性POPs的研究主要集中在外消旋体水平上,在对映体层面研究环境中手性POPs的历史并不长.但由于手性POPs不同对映体在生物学效应方面存在显著的差异,因此,手性POPs环境行为及其潜在生态风险对映体选择性效应更应值得重视.本文将在对映体水平上对手性POPs在各环境介质中的迁移、转化、生物体内的富集以及毒理学效应等方面的研究进行综述.     

我国典型电子垃圾拆解地持久性有毒化学污染物污染现状

电子垃圾拆解所引起的环境问题已经受到广泛关注,根据联合国环境规划署统计,全球约70%的电子垃圾通过各种途径进入我国,而我国自身也产生大量的电子垃圾。我国电子垃圾拆解活动采用的工艺较为原始,位于广东的贵屿和浙江的台州是我国最大的两个电子垃圾拆解地,拆解过程中电子垃圾本身含有和不当处置所产生的大量持久性有毒化学污染物(如重金属、二 NFDA1 英类、溴代阻燃剂等)释放到环境中,对拆解地生态系统及居民健康造成严重的威胁。本文重点针对我国电子垃圾拆解所造成的持久性有毒污染物(PTS)污染现状、管理措施和法规、拆解区居民所面临的持久性有毒污染物暴露健康风险及其相关研究最新进展进行了分析和概括,并对电子垃圾拆解区域持久性有毒污染物及新型环境污染物研究和发展方向作了展望。     

土壤和沉积物中持久性有机污染物分析的不确定度评估

土壤和沉积物中POPs分析过程中的不确定度来源于样品制备、运输和保存、前处理和分析4个环节.土壤经四分法采样、均质化制样、快速溶剂萃取、多层符合硅胶柱净化、GC/MS分析.以p,p'-DDT为例,评定了各环节不确定度的大小,结果表明:样品前处理的不确定度分量对合成不确定度的贡献最大,约占90.6%;样品制备、保存和分析...     

持久性有机化学污染物(POPs)的定性与定量分析

目前在持久性有机污染物研究方面出现了许多新的研究动向、研究计划相关环境条约以及新的名词.例如:POPs(Persistent Organic Pollutants)持久性有机污染物;PBT(Persistent Bioaccumulative& Toxic Chemicals);持久性生物可积累性毒性化合物;BFRs(Brominated Flame Retardants)溴化阻燃剂;EEDs(Environmental Endocrine Disruptors)环境内分泌干扰物,PTS(Persistent Toxic Substances)等.     

Catalytic electrochemical pre-treatment for the degradation of persistent organic pollutants

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Dechlorination of persistent organic pollutants polychlorobiphenyls by catalytic carbonylation

A new approach to dechlorination of “dioxin-like” ecotoxicants, polychlorinated biphenyls, based on carbonylation, was suggested. The weakly reactive aryl halides are activated by effective catalytic systems based on epoxide-modified cobalt carbonyl in alcoholic alkali solutions.     

Separation and preconcentration of persistent organic pollutants by cloud point extraction

Persistent organic pollutants (POPs) are recognized as a class of poisonous compounds which pose risks of causing adverse effects to human health and the environment. Thus, it is very important to detect POPs in environmental and biological samples. The identification and determination of very low levels of POPs in complex matrices is extremely difficult. Recently a promising environmentally benign extraction and preconcentration methodology based on cloud point extraction (CPE) has emerged as an efficient sample pretreatment technique for the determination of trace/ultra-trace POPs in complex matrices. The purpose of this paper is to review the past and latest use of CPE for preconcentrating POPs and its coupling to different contemporary instrumental methods of analysis. First, the comparison of various extraction techniques for POPs is described. Next, the general concept, influence factors and other methods associated with CPE technique are outlined and described. Last, the hyphenations of CPE to various instrumental methods for their determination are summarized and discussed.     

Advances in the gas chromatographic determination of persistent organic pollutants in the aquatic environment

Environmental chemists have been challenged for over 30 years to analyse complex mixtures of halogenated organic pollutants like polychlorinated biphenyls (PCBs), polychlorinated alkanes (PCAs), polybrominated diphenyl ethers (PBDEs) and polychlorinated dibenzo-p-dioxins and polychlorinated furans (PCDD/Fs). Gas chromatography (GC) often proved to be the method of choice because of its high resolution. The recent developments in the field of comprehensive two-dimensional GC (GCxGC) show that this technique can provide much more information than conventional (single-column) GC. Large volume injection (e.g. by programmed temperature vaporiser, or on-column injection) can be employed for the injection of tens of microliters of sample extract, in that way substantially improving the detection limits. Electron-capture detection (ECD) is a sensitive detection method but unambiguous identification is not possible and misidentification easily occurs. Mass spectrometric (MS) detection substantially improves the identification and the better the resolution (as with MS/MS, time-of-flight (TOF) MS and high-resolution (HR)MS), the lower the chances of misidentification are. Unfortunately, this comes only with substantially higher investments and maintenance costs. Co-extracted lipids, sulphur and other interferences can disturb the GC separation and detection leading to unreliable results. Extraction, and more so, sample clean-up and fractionation, are crucial steps prior to the GC analysis of these pollutants. Recent developments in sample extraction and clean-up show that selective pressurised liquid extraction (PLE) is an effective and efficient extraction and clean-up technique that enables processing of multiple samples in less than 1h. Quality assurance tools such as interlaboratory studies and reference materials are very well established for PCDD/Fs and PCBs but the improvement of that infrastructure is needed for brominated flame retardants, PCAs and toxaphene.     

Using gas chromatography with atomic emission detection for determining organic pollutants in water

The efficiency of gas chromatography with atomic emission detection (AED) for determining the composition of complex mixtures of organic water pollutants was studied by the example of 13 compounds of different classes. It was found that the correlation between the ratio of AED signals for single element atoms of the compound in the sample and their predetermined ratio in individual solutions additionally supports the identification of impurities in water at a trace level. The determination of a compound by the concentration of one or two elements in its molecule allows the evaluation of the effect of interfering impurities on the results of analysis.     

Application of micro-solid-phase extraction for the determination of persistent organic pollutants in tissue samples

A novel, simple and efficient method for determining persistent organic pollutants (POPs) in tissue samples has been developed. This technique involves the use of simultaneous microwave-assisted digestion (MAD) and micro-solid-phase extraction (micro-SPE), in which the sorbent is held within a propylene membrane envelope, with gas chromatographic-mass spectrometric (GC-MS) analysis. The POPs studied included eleven organochlorine pesticides and five polychlorinated biphenyl congeners. Optimization of the MAD-micro-SPE parameters was performed. The relative standard deviations (RSDs) of the method ranged from 0.14 to 12.7%. Correlation coefficients up to 0.9999 were obtained across a concentration range of 1.25-50 ng g(-1). The method detection limits for POPs ranged from 0.002 to 0.009 ng g(-1). A preliminary study applying the MAD-micro-SPE procedure to human ovarian cancer tissue showed that it was capable of detecting the presence of a wide spectrum of different POPs in benign and malignant tumors.