EAGER: Quantifying Spatial Distribution of Micro- and Nanoplastics along an Antarctic Traverse

微塑料和纳米塑料是从石油中提取的各种合成或半合成有机化合物制成的，自20世纪50年代开始大规模生产以来，在世界上已变得无处不在。最近的研究发现，在最原始的环境中观察到了这些污染颗粒，包括北极和南极洲。目前缺乏关于微塑料和纳米塑料如何在远离污染源的地区(例如城市)分布的数据。更好地了解它们的分布将有助于建立模型，告诉我们这些粒子在我们星球上的命运。就南极洲而言，现有的为数不多的关于微塑料和纳米塑料的研究主要集中在海水中的这些污染物上，只有一项研究集中在罗斯岛附近冰雪上采集的样本。这个迫切的项目将利用一位英国探险家在一次无人值守的滑雪穿越南极洲时收集的雪样，这将把他从南极洲海岸带到南极。然后，将使用最先进的设施对样品进行微塑料和纳米塑料的分析。数据分析将解决以下问题：地球上是否仍有未被微塑料和纳米塑料污染的原始区域？这些污染物在南极积雪中的浓度是多少？这个项目将量化南极从海岸到内陆的微塑料和纳米塑料的空间分布。结果将提供更好的过程理解，并支持开发可用于量化微塑料的时空演变和更好地评估它们如何与大气相互作用的模型。纳米塑料可以小于2.5微米，因此没有很好地表征这些方法的局限性。由于这些颗粒能够穿透各种生物的身体，如浮游植物、浮游动物、鱼类和细菌，因此这些颗粒对生态系统非常重要。该项目将使用超灵敏的受激拉曼散射(SRS)平台来表征小于2.5微米的纳米塑料。SRS是由该团队开发的，已被证明是在这种规模上研究纳米塑料对健康影响的一项强大技术。导线上采集的样本提供了一个独特的机会，可以更好地了解地球上最偏远地区的塑料沉积通量，重要的是，它显示了从周围海洋到南极科学基地塑料的浓度是如何变化的。假设微塑料和纳米塑料将受到当地人类活动(例如在南极)的影响，也可能受到横跨大陆的风的长距离运输的影响。南极穿越期间获得的数据与新的SRS平台相结合，使该项目从技术角度来看是独一无二的。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Microplastics and nanoplastics are generated from a wide range of synthetic or semi-synthetic organic compounds derived from petroleum and have become ubiquitous in the world since mass production began in the 1950s. Recent research has found that these polluting particles have been observed in the most pristine environments, including the Arctic and Antarctica. There is currently a lack of data on how microplastics and nanoplastics are distributed in areas that are far away from contaminating sources (e.g., cities). A better understanding of their distribution would help to build the models that can tell us the fate of such particles on our planet. In the case of Antarctica, the few existing studies of microplastics and nanoplastics have focused primarily on these pollutants in ocean waters, apart from one study that focused on samples collected over ice and snow in the vicinity of Ross Island. This EAGER project would leverage samples of snow collected by a British explorer during an unsupported ski traverse across Antarctica that will lead him from the coast of Antarctica to the South Pole. Samples will then be analyzed for microplastics and nanoplastics using a state-of-the-art facility. The data analysis will address the questions: Are there still pristine areas on Earth that have not been contaminated by microplastics and nanoplastics? What is the concentration of these pollutants within the South Pole snow?This project will quantify the spatial distribution of Microplastics and nanoplastics in Antarctica from the coast to the interior. Results will provide a better process understanding and support the development of models that can be used to quantify the spatio-temporal evolution of microplastics and to better assess how they interact with the atmosphere. Nanoplastics can be smaller than 2.5 µm and are therefore not well characterized due limitations in the methods. These particles are of great concern for the ecosystem due to their ability to penetrate the bodies of various organisms, such as phytoplankton, zooplankton, fish, and bacteria. This project will use an ultrasensitive Stimulated Raman Scattering (SRS) platform to characterize nanoplastics smaller than 2.5 µm. The SRS was developed by this team and has proven to be a powerful technology for studying the health impact of nanoplastics at this scale. The samples collected on the traverse offer a unique opportunity to better understand the depositional fluxes of plastic in the remotest region on Earth, and importantly, show how the concentration of plastics vary from the surrounding oceans to the scientific base at the South Pole. The hypothesis is that microplastics and nanoplastics will be affected by both local human activities (e.g., at South Pole) and possibly by the long-range transport by winds across the continent. The combination of the data acquired during the Antarctic traverse and the new SRS platform makes this project unique from a technical point of view.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.