State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China.
University of Chinese Academy of Sciences, Beijing 100190, China.
Environ Sci Technol. 2018 Feb 6;52(3):1088-1095. doi: 10.1021/acs.est.7b06317. Epub 2018 Jan 16.
Airborne particulate pollution is a critical environmental problem affecting human health and sustainable development. Understanding of the sources of aerosol particles is of extreme importance for regional air pollution control. Here we show that natural Si isotopic signature can be used as a new tool to elucidate the sources of fine particulate matter (PM). Through the analysis of Si isotopic composition (δSi) of PM and its primary sources collected in a typical pollution region - Beijing, we recognized the direct source tracing ability of Si isotopes for PM. The different primary sources of PM had different Si isotopic signatures. The δSi value of PM ranged from -1.99‰ to -0.01‰ and showed a distinct seasonal trend (isotopically lighter in spring/winter and heavier in summer/autumn). The variations in δSi of PM revealed that Si-isotopically light sources were important sources for Beijing's severe haze pollution and that coal burning was a major cause for the aggregating haze weather in spring/winter in Beijing. We also analyzed several typical haze events by using Si isotopic signatures. As the first study on the natural Si isotopes in the atmospheric environment, this study may reveal an important tool to advance the particulate pollution research and control.
大气颗粒物污染是影响人类健康和可持续发展的一个关键环境问题。了解气溶胶粒子的来源对于区域空气污染控制至关重要。在这里，我们表明，天然硅同位素特征可作为阐明细颗粒物（PM）来源的新工具。通过对在北京这一典型污染地区采集的 PM 及其主要来源的 Si 同位素组成（δSi）进行分析，我们认识到 Si 同位素对 PM 的直接溯源能力。不同的 PM 主要来源具有不同的 Si 同位素特征。PM 的 δSi 值范围为-1.99‰至-0.01‰，并表现出明显的季节性趋势（春季/冬季较轻，夏季/秋季较重）。PM 的 δSi 变化表明，硅同位素较轻的来源是北京严重雾霾污染的重要来源，而燃煤是北京春季/冬季雾霾天气聚集的主要原因。我们还利用 Si 同位素特征分析了几个典型的雾霾事件。作为大气环境中天然硅同位素的首次研究，本研究可能揭示了推进颗粒物污染研究和控制的一个重要工具。
