Stable metal isotopes as discriminators of combustion and non-combustion sources in atmospheric particulates: A proof of concept study using two megacities in China

稳定金属同位素作为大气颗粒物中燃烧源和非燃烧源的鉴别器：基于中国两个大城市的概念验证研究

• 批准号: 403804185
• 负责人: Dr. Nina Schleicher
• 金额: --
• 依托单位: Department of Earth Science & Engineering
• 依托单位国家: 德国
• 项目类别: Research Fellowships
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/403804185?language=en
• 关键词: Stable; metal; isotopes; discriminators; combustion

Combatting air pollution is one of the great challenges urban environments of the future face. Of great concern, in particular, is the increase in particulate matter emissions and the associated high concentration of toxic metals. Identifying the sources of the toxic metals remains one of the great challenges because the methods developed so far (based on statistical methods) are often inconclusive and expensive (computational and analytically). To this end, the application of isotope ratios is of great interest because with this technique we can specifically target elements of interest. The development of a new generation of plasma source mass spectrometers has enabled to apply isotopes systematics for source tracing of metals and recent work pioneered by a group of researchers at Imperial College London suggests that these new isotope systems enable to identify sources of Cu and Zn in urban particles. Work in major urban cities around the world showed significant isotopic variations and there is strong evidence that isotopically very heavy and light isotope signatures point to sources from industrial combustion while the range in-between points to sources derived from vehicular emissions, i.e. tires and brakes. If this can be confirmed, then a major new tool in identifying sources of these toxic metal will enable urban planners to address and combat air pollution in their city. To test this hypothesis, I – as part of a team at Imperial College London – propose to analyze the isotopic composition of aerosols in two megacities with distinct different emission scenarios. Hong Kong is dominated by particulate matter emissions derived from traffic and Beijing is dominated by coal emissions during winter and traffic in the summer. We aim to analyze the isotopic compositions of these aerosols over the span of one whole year and, additionally, the key sources (tires and brakes from cars, coal seams from China, emissions from smelters and other combustion emissions). To support the source identification, we will carry out mineralogical and geochemical analyses of the particulate aerosols. Finally, we will critically compare calculated source apportionment using isotopic and non-isotopic techniques and evaluate the potential of this new tracer.

对抗空气污染是未来城市环境面临的重大挑战之一。 特别令人严重关切的是，颗粒物排放量增加，有毒金属浓度也随之升高。确定有毒金属的来源仍然是最大的挑战之一，因为迄今为止开发的方法（基于统计方法）往往是不确定的和昂贵的（计算和分析）。为此，同位素比的应用是非常有趣的，因为使用这种技术，我们可以专门针对感兴趣的元素。新一代等离子体源质谱仪的发展使得能够应用同位素系统学来追踪金属的来源，并且由伦敦帝国理工学院的一组研究人员开创的最新工作表明，这些新的同位素系统能够识别城市颗粒物中的Cu和Zn的来源。在世界各地主要城市开展的工作表明，同位素差异很大，有强有力的证据表明，同位素的超重和轻同位素特征表明来源于工业燃烧，而两者之间的范围则表明来源于车辆排放，即轮胎和刹车。如果这一点能够得到证实，那么一个确定这些有毒金属来源的重要新工具将使城市规划者能够解决和应对城市的空气污染。为了验证这一假设，我--作为伦敦帝国理工学院一个团队的一员--提议分析两个具有明显不同排放情景的特大城市气溶胶的同位素组成。香港主要是由交通产生的颗粒物排放，北京主要是冬季的煤炭排放和夏季的交通排放。我们的目标是在一整年的时间内分析这些气溶胶的同位素组成，此外，还分析主要来源（汽车的轮胎和刹车、中国的煤层、冶炼厂的排放物和其他燃烧排放物）。为了支持来源识别，我们将对颗粒气溶胶进行矿物学和地球化学分析。最后，我们将批判性地比较计算源解析使用同位素和非同位素技术，并评估这种新的示踪剂的潜力。