广州地区典型多溴联苯醚迁移和归趋行为模拟

运用多介质逸度模型对典型PBDEs(BDE47、BDE99、BDE209)在广州地区大气、水体、土壤、沉积物中的浓度分布与多介质间的迁移、归趋进行了模拟研究并分析了3种化合物在研究区域环境多介质间的迁移通量,确定其在环境中的主要迁移过程;结合实际监测数据,对模型的可靠性进行验证;以BDE47和BDE209为例,对模型的输入参数进行灵敏度分析;并以BDE209为例,对模型进行不确定性分析.通过模拟浓度与实测浓度的对比,表明模型在该地区具有很好的适用性.结果表明,环境系统达到平衡时,BDE47、BDE99和BDE209在土壤和沉积物中的含量分别占其在环境系统总含量的17.73%和82.26%,14.65%和85.35%,4.81%和95.19%;PBDEs从环境系统中的消失途径主要为大气平流输出和土壤降解;logKow和大气平流输入是影响化合物在环境相中浓度分布的最主要因素;不确定性分析指出BDE209在土壤相中浓度的变异系数最大.

Simulating the transfer and fate of typical PBDEs in Guangzhou

A multimedia fugacity model was applied to simulate the concentrations distribution, transfer and fate of typical polybrominated diphenyl ethers (BDE47、BDE99、BDE209) in air, water, soil, sediment of Guangzhou Area. Meanwhile, the transfer fluxes between different compartments were analyzed in order to infer the main transfer process. Moreover, the simulated concentrations in air, soil and sediment were compared to monitored data for validation purpose. In addition taking BDE47and BDE209as samples, input parameters of the model were tested and the key parameters were identified using sensitivity analysis method, while the uncertainty of these key parameters was estimated taking BDE209as sample. The reliability of the model was verified by the agreement between calculated and measured concentrations. When the system reaches equilibrium, soil and sediment compartments were the main reservoirs of PBDEs in Guangzhou area because of the mass fraction of BDE47、BDE99 and BDE209 in soil and sediment of the total content, respectively, were 17.73% and 82.26%, 14.65% and 85.35%, 4.81% and 95.19%;The air advection outflow and soil degradation were the major routes for PBDEs to disappear in the study area. The results of sensitivity analysis in this study also indicated that the logKow、air advection inflow had significant influence on concentrations of PBDEs in various media. Uncertainty analysis for environmental multimedia fugacity model predicted that the coefficient of variation of BDE209in the soil concentrations had the most significant compared with others.