典型有机污染物的界面传输特征及其调控机制

Inter-compartmental exchange of organic contaminants is a critical factor for controlling to their environmental fate, as well as ecological and human health effects. The present proposed study will select typical organic contaminants, such as polycyclic aromatic hydrocarbons, polybrominated diphenyl ethers and organophosphate flame retardants as the target compounds, and examine their behaviors across the sediment-water, soil-air and water-air interfaces through laboratory simulation studies. Meanwhile, the exchange fluxes of the target compounds impacted by different environmental factors across these three interfaces will be measured. The governing mechanisms for the inter-compartmental fluxes will be examined by combining flux data under different conditions with absorption/desorption mechanisms in the environmental matrix. We also intend to calibrate a micro-environment multi-fate model with the measured parameters obtained from laboratory simulation. In addition, we will examine the reaction or partition mode of the target compounds between the gaseous and particulate phases, as well as the governing factors. Alternatively, the mechanisms for binding of the target compounds between the gaseous and particulate phases under different conditions will be investigated through instrumental analysis. The results from this proposed study is expected to acquire scientific data in support of China’ efforts to fulfill its obligations with international environmental treaties.

有机污染物的环境界面行为是控制其环境归宿及生态和人体健康效应的决定性因素。本项目拟选择典型有机污染物，如多环芳烃、多溴联苯醚及有机磷阻燃剂作为目标物，基于室内模拟系统研究目标物在沉积物-水体、土壤-大气、水体-大气界面间的行为特征，测定目标物在三大主要环境界面的交换通量及在不同因素影响下通量的变化；结合目标物在环境介质上吸附/解吸机理，从微观尺度上探讨其影响界面交换通量的机制，同时将室内实测的参数与稳态/非稳态的逸度模型结合，建立结合环境条件的微系统环境多介质模型。同时，本项目亦拟开展颗粒物与气态化合物结合机制的探索性研究，通过产生粒径大小设定的颗粒物，探究目标物与颗粒物的结合方式，并明晰颗粒物自身性质、环境温度、湿度等对结合动力学的影响，通过仪器表征手段研究目标物在不同环境条件下与颗粒物结合的微观机理，反演其排放方式。本项目的研究结果预期可为我国履行国际公约提供科学依据。

有机污染物的环境界面行为是控制其环境归宿及生态和人体健康效应的决定性因素。本项目首先研制了同步荧光探测仪，用于获得荧光污染物在水-大气界面的高精度浓度分布，其精度与传统被动采样器相比提高了2个数量级，并首次表征了芘在水-大气界面的微表面层厚度及迁移通量；其次，建立了温度及有机质变化与目标污染物在沉积物-水界面迁移通量变化的定量模型，并确认了化合物性质及土壤含水率是影响多溴联苯醚及磷系阻燃剂土-气迁移通量的主控因子，为明晰有机污染物环境界面行为提供了方法支撑及模型参数；再次，通过模拟研究，考察了不同源释放颗粒态多环芳烃以及阻燃剂（多溴联苯醚、有机磷阻燃剂及新型卤代阻燃剂）的排放因子及特征，探明了颗粒态阻燃剂在热解及燃烧过程中的排放机制，为探究污染物在颗粒相与气相之间的分配机制提供了基础数据；最后，建立新型环境逸度模型，评估了阻燃剂在中国不同区域内环境介质间的迁移通量。此外，我们还建立了深度卷积神经网络模型并将其用于从化学工业品目录里筛选潜在环境持久性毒害有机污染物，为化学品安全管控提供了数据清单。