CAS-MNP: Evaluating Degradation Products and Changes in Colloidal Properties of Microplastics During Photochemical Weathering

CAS-MNP：评估光化学风化过程中微塑料的降解产物和胶体性质的变化

• 批准号: 2204145
• 负责人: Laodong Guo
• 金额: $ 36.08万
• 依托单位: University of Wisconsin-Milwaukee
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2204145&HistoricalAwards=false
• 关键词: CAS; MNP; Evaluating; Degradation; Products

This award is supported by the Environmental Chemical Sciences (ECS) Program in the NSF Division of Chemistry. Professor Laodong Guo and his students in the School of Freshwater Sciences at University of Wisconsin-Milwaukee will study the weathering of microplastics / microfibers in aquatic environments. The kinetics, products, and mechanisms of these degradation processes will be determined. Microplastics and nanoplastics are ubiquitous, persistent, and toxic in aquatic environments and have been recognized as emerging contaminants. Nanoplastics are believed to have higher toxicity to organisms. The project will integrate research, education, and outreach through the participation of graduate and undergraduate students, especially underrepresented students and undergraduate research fellows, promote multidisciplinary collaborative research, and augment the training of graduate and undergraduate students in environmental chemistry and freshwater sciences. Microplastics are an important issue in the Great Lakes Region and subject increasing regulation by local and state ordinances. The project team will work with relevant federal/state agencies, stakeholders, and the general public, including K12 students, to share research findings on the fate and transport of microplastics in aquatic environments and their potential impacts on ecosystem and human health.Despite their importance, little is known about the fundamental environmental chemistry of micro- and nano-plastics (MNP), photochemical reactivities, and changes in their surface and colloidal properties and environmental behavior during and after weathering. To fill the knowledge gap, the project team will conduct research using controlled laboratory experiments on representative microplastics and microfibers. The degradation products from microplasics, including dissolved organic molecules and nanoplastics, will be characterized for chemical and optical properties using total organic carbon analyzer and ultraviolet-visible and fluorescence spectroscopy. Changes in surface and colloidal properties, such as zeta-potential and hydrodynamic size-distribution, will be determined using dynamic light scattering technique and asymmetrical flow field-flow fractionation coupled with multiple angles light scattering detectors. In addition, Fourier-transform infrared spectroscopy and Micro-Raman spectroscopy will be used to characterize plastic polymers and functional groups.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.

该奖项由NSF化学部的环境化学科学（ECS）计划支持。威斯康星大学密尔沃基分校淡水科学学院的郭劳东教授和他的学生将研究微塑料/微纤维在水生环境中的风化。 这些降解过程的动力学，产品和机制将被确定。微塑料和纳米塑料在水生环境中普遍存在，持久性和毒性，已被公认为新兴污染物。纳米塑料被认为对生物体具有更高的毒性。该项目将通过研究生和本科生，特别是代表性不足的学生和本科生研究员的参与，整合研究，教育和推广，促进多学科合作研究，并加强对研究生和本科生在环境化学和淡水科学方面的培训。微塑料是五大湖地区的一个重要问题，受到地方和州法令越来越多的监管。该项目团队将与相关的联邦/州机构、利益相关者和公众（包括K12学生）合作，分享关于微塑料在水生环境中的命运和运输及其对生态系统和人类健康的潜在影响的研究成果。尽管它们很重要，但人们对微塑料和纳米塑料（MNP）的基本环境化学、光化学反应、以及在风化过程中和风化后其表面和胶体性质以及环境行为的变化。为了填补这一知识空白，项目团队将使用受控实验室实验对代表性的微塑料和微纤维进行研究。微塑料的降解产物，包括溶解的有机分子和纳米塑料，将使用总有机碳分析仪和紫外-可见和荧光光谱仪表征其化学和光学性质。表面和胶体性质的变化，如zeta电位和流体动力学尺寸分布，将使用动态光散射技术和不对称流场流分馏与多角度光散射检测器相结合来确定。此外，傅里叶变换红外光谱和显微拉曼光谱将用于表征塑料聚合物和官能团。该奖项反映了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，被认为值得支持。