沙尘颗粒的组分甄别、化学转化机制及毒性效应

近些年，我国北京等北方区域再次发生沙尘暴污染事件，且频率增加。沙尘天气颗粒物浓度急剧飙升，沙尘颗粒的组分与雾霾颗粒有明显差别，沙尘天气急剧增加的颗粒物浓度加之组分的变化，将导致沙尘颗粒毒性效应的演变。本项目将应用前期建立的毒性组分甄别方法学，对沙尘颗粒的组分变化、转化机制及其毒性演变开展如下研究：（1）利用多谱学技术甄别沙尘天气下颗粒物的关键无机和有机毒性组分，阐明关键毒性组分类别及含量的演变规律；（2）通过电子顺磁共振波谱与色谱/高分辨质谱技术相结合，甄别沙尘颗粒中重要毒性组分-长寿命自由基的精细结构，揭示沙尘颗粒物表面长寿命自由基等介导的化学转化反应；（3）针对筛查出的沙尘颗粒中的关键毒性组分，开展离体及活体毒理学实验，揭示沙尘颗粒的生物毒性及在沙尘前后的毒性演变规律。本项目将在沙尘颗粒的组分甄别、化学转化机制及毒性演变方面取得突破，为了解沙尘天气颗粒物的毒理与健康效应提供科学依据。

Despite the decline of sandstorm frequency several decades ago, northern China including Beijing has been struck by sandstorms again in recent years with increasing frequency. Sandstorm particulate matters are featured with soared concentration and significantly different chemical composition compared to the intractable haze particles, which will lead to sandstorm particulate matters toxicity evolution and uncertain risks to human health. Based on our previously established screening methodology for toxic component, this project will carry out the following studies on the composition analysis, transformation mechanism and toxicity effects of sandstorm particulate matters: (1) screening the pivotal toxic organic and inorganic components, and clarifying their composition variation and concentration evolution rules by adopting multiple-spectral technologies; (2) identifying the hyperfine splitting structure of persistent free radicals in sandstorm particulate matters and clarifying their chemical transformation reactions on the surface of sandstorm particulate matters through the combined use of electron paramagnetic resonance and gas chromatography/high-resolution mass spectrometer, which are significant for understanding the influence of sandstorm on atmospheric environment; (3) conducting in vitro and in vivo toxicological tests according to the detected pivotal toxic components, and revealing their biological toxicity and even toxicity evolution mechanisms. This project aims to achieve breakthroughs in the composition analysis and their chemical transformation mechanism and toxic effects of sandstorm particulate matters and to provide scientific basis for understanding their toxicology and health effects.