短链氯化石蜡的环境行为与毒理

Short chain chlorinated parafins (SCCPs), which has been listed as candidate POPs, are a group of complex mixtures. China is the largest producer and consumer of chlorinated paraffins, and the concentrations of SCCPs in Chinese environment were found to be higher. So the ecological risk and human health risk induced by SCCPs pollution should be seriously concerned. This project focuses on the assessment of ecological risk and human health risk of SCCPs. First, the more precise analytical methods of SCCPs will be developed; then using this analytical method the significant emission sources, including the production and usage of chlorinated paraffin, e-waste disposal, and the heating treatment of plastics containing SCCPs, will be investigated and characterized. The air transport and deposition of SCCPs from the emission sources will be described. The SCCPs pollution in the environments and the human exposure around the emission sources will be investigated. Meanwhile, the concentration and distribution of SCCPs in the indoor environment will be investigated, and thereby the human intake of SCCPs in the indoor environment will be evaluated. Moreover, the main metabolites of SCCPs in the model organisms will be identified, and then the DNA damage in model organisms and the toxic effects on human cells induced by SCCPs and their metabolites will be studied. In addition, toxicological mechanism of SCCPs in gonad and hypothyroid systems will be also explored. The obtained results will be available for the environmental management, convention implementation and convention establishment of SCCPs.

短链氯化石蜡（SCCPs）组成复杂，已被列入POPs候选者清单。我国是氯化石蜡生产和使用最多的国家，SCCPs在我国的环境中存量较高，因此应对其所引起的生态风险和人体健康风险给予高度关注。本项目围绕着揭示SCCPs污染的生态风险和人体暴露风险这一主题开展研究工作。首先是建立更为精准可靠的SCCPs分析方法；在此基础上，研究氯化石蜡生产和工业使用过程、废物回收利用过程、电子垃圾拆卸过程和含SCCPs塑料加热过程SCCPs的大气排放特征、污染大气迁移-沉降过程、及其所引起的周边环境污染和人体暴露风险，揭示室内空气中SCCPs的分布特征，评估人体室内暴露摄入量。同时，鉴定出SCCPs的主要代谢降解产物，并研究SCCPs及其主要代谢降解产物对模式生物的DNA损伤、对性腺和甲状腺系统的致毒机制、以及对人体细胞的毒性效应。获得的结果可用于我国与SCCPs相关的环境管理、公约履行和公约制定。

短链氯化石蜡（SCCPs）组成复杂，已被列入持久性有机污染物清单。我国是氯化石蜡生产和使用最多的国家，SCCPs在我国的环境中存量较高，因此应对其所引起的生态风险和人体健康风险给予高度关注。本项目围绕着揭示SCCPs污染的生态风险和人体暴露风险这一主题开展研究工作。在分析技术方面，创新性发展了SCCPs的氘代脱氯-高分辨色谱-高分辨质谱分析方法，实现了不同氯化度和不同碳链长度SCCPs同族体的精准定量分析；同时，改进优化了SCCPs的碳骨架催化加氢分析方法。在环境行为方面，揭示了SCCPs在渤海海域的环境迁移及生物累积，发现SCCPs具有极强的生物富集性，在近海底栖生物中累积量较高，并具有沿食物链中累积放大效应；揭示了氯化石蜡生产和使用过程中SCCPs的污染迁移扩散行为，发现SCCPs向周边土壤的污染扩散主要通过颗粒物沉降方式进行，而SCCPs的气相传输扩散行为符合高斯扩散模型，并且扩散过程伴随着明显的污染物“分馏效应”；同时，发现SCCPs在皮革化工区域呈现面源污染特征；模拟研究了聚氯乙烯（PVC）产品加工过程中SCCPs的释放行为，发现PVC地板革在100−200 °C的受热条件下1小时内可释放1.9−10.7%的填加SCCPs, 绝大部分释放的SCCPs分配在纳米级颗粒物中，预示着PVC产品加工会导致极高的SCCPs呼吸暴露风险。揭示了室内环境中 SCCPs的污染特征、及人体暴露风险，发现商场和建材仓库是SCCPs的高暴露场所。毒代动力学实验结果表明，SCCPs在大鼠血液中的半衰期为6.6天。通过开展人体肝癌细胞HepG2、SD大鼠和斑马鱼暴露试验，基于代谢组学和转录组学研究手段，结合常规生物分析，揭示了SCCPs的主要毒性效应。发现SCCPs对脂肪代谢、氨基酸代谢和核苷酸代谢和能量代谢有强烈干扰。SCCPs主要通过与PPARα相结合介导一系列毒性效应；同时，发现SCCPs可诱导较强的氧化胁迫效应，并可通过组成型雄甾烷受体（CAR）介导机制干扰肝脏甲状腺激素转运和降解，从而引起甲状腺激素水平紊乱。此外，初步揭示了SCCPs在普通人群血液和胎盘中的污染水平。获得的结果可用于我国与SCCPs相关的环境管理、公约履行和公约制定。