短链氯化石蜡的全二维气相色谱分析方法及其在大气中环境行为研究

Short Chain Chlorinated paraffins (SCCPs), are industrial contaminants, which are persistent, toxic and bioaccumulative. The analysis of SCCPs is a difficult task and today only semi-quantitative determination can be performed because of the complexity of the mixtures and the lack of quantification standards. The analysis of SCCPs in different samples such air, soil and sediment will be studied in this programm. SCCPs are extracted from soil, sediments or polyurethane-foam filters employed for air sampling by applying ASE. Activated copper, Florisil will be added to the sample for purification before extraction. Then, the samples were cleaned up by several chromatographies such as sulphuric acid-silica gel column chromatography, multi-layer gel column chromatography and florisil chromatography and gel permeation florisil (GPC). It is very useful because the PCDD/Fs, PCBs, PCNs, HCB can also purified by this clean-up procedures. Comprehensive two-dimensional gas chromatography (GC×GC), well known for its overall improved separation, was evaluated for the separation of SCCPs mixtures. The detection limit should be less than 0.01ng/g. The atmosphere is usually considered to be the main transport medium for most SVOCs. However, very few studies have been conducted to investigate the atmospheric levels and distribution of SCCPs. This study will investigate the concentrations, gas-particle partitioning of SCCPs and complex environmental processes like volatilization and fractionation of SCCPs in the air in some city and rural. Different gas particle partitioning models were further used to regress and to compare with the field data in combination with predicted physical-chemical properties. Further discussions on the rigidity of the results were put forth in view of the lack of consistent data on relevant physical-chemical properties for SCCPs and also on other influencing factors.

短链氯化石蜡（SCCPs）在环境中具有持久性，生物蓄积性，生物毒性，是一种新型的持久性有机污染物，已被列入斯德哥尔摩公约拟增列名单。SCCPs种类繁多且结构复杂，目前不能对其准确定性和定量，分析仍面临重大挑战。本课题拟开展SCCPs定性和定量分析方法研究，在样品净化方面，拟开展多种复合柱组合净化，实现短链氯化石蜡与多种POPs的同步净化分离，有效降低实验费用与分析周期。利用二维气相色谱法对SCCPs准确定性及定量，检出限低于0.01ng/g。我国是氯化石蜡生产大国，环境中SCCPs鲜有报道，其污染状况不明。本课题在建立方法的基础上，在两个典型城市和农村开展大气样品采集，研究其气/固分配，干湿沉降过程，土/气交换，水/气交换过程等环境行为，并研究SCCPs在大气中的归宿、行为预期与物理化学性质logKp、logKw、与Kop等之间的关系，为SCCPs的环境风险评价及污染控制与治理提供依据。

氯化石蜡（CPs）是一类组成复杂的正构烷烃的氯代衍生物，种类繁多,分离分析困难。本课题通过优化色谱和质谱条件，建立了全二维气相色谱电子捕获检测器（GC×GC-μECD）和全二维气相色谱-负化学电离源-高分辨飞行时间质谱（GC×GC-ECNI-HRTOF-MS）定性定量分析SCCPs和MCCPs的方法，本方法极大地改善了不同碳链长度、不同氯取代氯化石蜡同类物的色谱分离度，实现了SCCPs和MCCPs的色谱分离，去除了来自CPs同类物之间的相互定量干扰。同时有效去除了其他相似POPs（如毒杀芬、多氯联苯和多溴二苯醚等）在CPs定量上存在的干扰，实现了48种SCCPs和MCCPs同类物的定量分析。将方法应用至沉积物和生物样品等多种环境介质中SCCPs和MCCPs的分析测定，方法回收率和重现性良好，SCCPs和MCCPs的方法检出限分别为5.6 ng/g和2.0 ng/g。本方法为环境样品中SCCPs和MCCPs的定量分析提供了新的思路。本课题在建立分析方法的基础上，研究了室内和室外大气中SCCPs和MCCPs的环境行为，发现室内中SCCPs与MCCPs含量高于室外，SCCPs与MCCPs在不同粒径颗粒物中的分配与其质量数相关，室外和室内空气中SCCPs和MCCPs的不同粒径上细小的分布差异可能受到它们的分子量、挥发性、采样点和排放源的影响。室外和室内颗粒物样品中SCCPs可能主要来自CP-42和CP-52的生产和使用。