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

微塑料和纳米塑料是由石油衍生的各种合成或半合成有机化合物产生的，自20世纪50年代开始大规模生产以来，它们在世界上无处不在。最近的研究发现，这些污染颗粒在最原始的环境中被观察到，包括北极和南极洲。目前缺乏关于微塑料和纳米塑料如何分布在远离污染源的地区的数据（例如，城市）。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，现有的几项关于微塑料和纳米塑料的研究主要集中在海洋沃茨中的这些污染物上，只有一项研究集中在罗斯岛附近的冰雪上收集的样本上。这个EAGER项目将利用一位英国探险家在南极洲无支撑滑雪穿越期间收集的雪样本，这将使他从南极洲海岸到达南极。然后将使用最先进的设施对样本进行微塑料和纳米塑料分析。数据分析将解决以下问题：地球上是否还有未被微塑料和纳米塑料污染的原始地区？这些污染物在南极雪中的浓度是多少？该项目将量化南极洲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时空演变的模型，并更好地评估它们如何与大气相互作用。纳米塑料可以小于2.5 μm，因此由于方法的限制而无法很好地表征。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，因此对生态系统非常关注。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由该团队开发，已被证明是研究这种规模的纳米塑料对健康影响的强大技术。在横贯线上收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，它显示了塑料的浓度如何从周围的海洋到南极的科学基地而变化。假设是微塑料和纳米塑料将受到当地人类活动的影响（例如，在南极），并可能通过风在整个大陆的长距离运输。在南极穿越期间获得的数据和新的SRS平台的结合使这个项目从技术的角度来看是独一无二的。这个奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为是值得支持的。

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.