基于中空纤维流场流分级的不同粒径大气颗粒物中重金属污染特征、溶出特性和生物有效性研究

大气颗粒物中重金属污染特征、环境效应和与生物毒性与其粒径密切相关。但现有的不同粒径大气颗粒物中重金属的分级分析方法多存在粒径分级有限、样品需求量大、非在线等不足，难以实现大气颗粒物的连续分级和分级组分中重金属的在线分析。本项目拟利用中空纤维流场流分级技术所具有的分级效率高、适用范围广、操作简便等优势，结合高灵敏的多元检测系统，建立不同粒径（从纳米级到微米级）大气颗粒物中重金属污染特征的在线分析方法；深入研究水环境中溶解性有机质、pH、离子强度、温度及氧化还原电位等因素对大气颗粒物中重金属溶出特性的影响；通过进一步研究大气颗粒物中重金属在模拟体液中的溶出情况，评价重金属进入人体后的生物有效性。项目的实施，可望深入了解颗粒物粒径与重金属污染特征的关系、揭示环境和体液相关因素对大气颗粒物中重金属的环境效应和生物有效性的影响机制，为科学评估大气颗粒物中重金属的环境安全及和健康风险提供重要依据。

The concentration, dissolution, and bioaccessibility of heavy metals in atmospheric particles are strongly dependent on the particle size. However, most of the currently available methods suffer from low fractionation ability, requiring large amounts of samples, and off-line operation, limiting the application in the continuous fractionation and on-line analysis of heavy metals in fractionated particles. In this proposal, we plan to (i) develop an on-line coupled hollow fiber flow field-flow fractionation (HF FlFFF) with multiple sensitive detectors for analyzing heavy metals in different sized atmospheric particles (from nm to μm) based on the excellent separation, wide applicability, and convenient operation of HF FlFFF; (ii) study the impact of dissolved organic matter, pH, ionic strength, temperature, and redox potential on dissolution characteristics of heavy metals in different size atmospheric particles; (iii) evaluate bioaccessibility of heavy metals using simulated body fluid. The implement of this project will reveal the mechanism for environmental effects resulted from the various environmental parameters and bioaccessibility of heavy metals within body liquid in different sized atmospheric particles, which are helpful to evaluate the environmental and health risks related to heavy metals in atmospheric particles.