Tracking emerging contaminants with isotope tools in green and engineered water infrastructure

拟议的研究将侧重于环境修复和新出现的污染物的水处理，包括微量有机化合物和微塑料。我们将在新的应用中使用化合物特定同位素分析（CSIA）来(i)深入了解反应机制，（ii）展示CSIA在新污染物（苯并三唑、三氯生、土臭素和2-甲基异龙脑）和新应用（绿色基础设施和饮用水处理厂）中的潜力。我将描述控制湿地、生物保留细胞和饮用水处理厂中污染物的命运和去除的转移和转化机制。人类活动使用了数千种化学物质，这些化学物质会进入雨水、废水和我们的淡水水生资源。其中一些化学品对人类和环境健康有已知的影响，但由于缺乏对其毒性的了解，许多化学品仍有待发现或不受管制。我的研究目标是改进修复措施的设计和实施。我将试图描述在绿色基础设施（包括人工湿地和生物保留细胞）中控制主要新兴污染物（即三氯生和苯并三唑）命运的机制。绿色基础设施是一种具有成本效益和节能的水处理方法，但在广泛采用之前必须变得更加可靠。虽然原则上湿地和生物保留细胞可以消除大部分污染物，但它们目前的性能变化很大。我的目标是通过提高我们对绿色基础设施内部流程的理解来提高其可靠性。具体来说，我将研究藻类和植物的作用，以补充现有的关于光和细菌作用的知识。将实验室结果转化为实际应用总是一项挑战。我将把实验室研究扩大到户外试点系统，例如，在多伦多大学科夫勒科学保护区和安大略省科特赖特的TRCA生物保留细胞，并将描述实际现场条件下涉及的过程。我将研究微塑料在生物滞留土壤中的积累以及从生物滞留细胞下向地下水渗漏的可能性。我将评估和修改生物保留细胞中悬浮固体运输和保留的现有模型，并使其适应微塑料，特别关注微塑料尺寸对运输和保留机制的影响。该模型将用于预测不同生物滞留介质和流动条件下生物滞留池中微塑料的去除效率。我还将研究两种味道和气味化合物的命运，即土臭素和2-甲基异冰片酚，在饮用水中。目的是为颗粒活性炭（GAC）床中这些化合物的吸附和生物降解的相对重要性提供原位明确的证据。

The proposed research will focus on environmental remediation and water treatment of emerging contaminants, including trace organic compounds and microplastics. We will use Compound Specific Isotope Analysis (CSIA) in novel applications to (i) gain insight in reaction mechanisms and (ii) demonstrate the potential of CSIA for new contaminants (benzotriazole, triclosan, geosmin, and 2-methylisoborneol) and new applications (green infrastructure and drinking water treatment plants). I will characterize the transfer and transformation mechanisms that govern the fate and removal of contaminants in wetlands, bioretention cells, and drinking water treatment plants. Human activities use thousands of chemicals that reach stormwater, wastewater, and our freshwater aquatic resources. Some of these chemicals have known impacts on human and environmental health, but many are still to be discovered or are unregulated due to lack of knowledge about their toxicity. The goal of my research is to improve the design and implementation of remediation measures. I will seek to characterize the mechanisms governing the fate of key emerging contaminants, i.e., triclosan and benzotriazole, in green infrastructure including constructed wetlands and bioretention cells. Green infrastructure is a cost-effective and energy-efficient approach to water treatment, but must become more reliable before it sees widespread adoption. While in principle wetlands and bioretention cells can eliminate a significant portion of contaminants, their present-day performance is highly variable. My objective is to improve the reliability of green infrastructure by advancing our understanding of their internal processes. Specifically, I will study the role of algae and plants to complement existing knowledge on the role of light and bacteria. Translating lab results to the field is always challenging. I will scale up lab studies to outdoor pilot systems, e.g., at the University of Toronto Koffler Scientific Reserve and the TRCA bioretention cell at Kortright, ON and will characterize the processes involved in real field conditions. I will investigate microplastic accumulation in bioretention soil and the potential for exfiltration below the bioretention cells towards groundwater. I will evaluate and modify existing models for suspended solids transport and retention in bioretention cells, and adapt them to microplastics, giving particular attention to the effect of microplastic size on transport and retention mechanisms. The model will be used to predict the efficiency of microplastic removal in bioretention cells with various bioretention media and flow conditions. I will also investigate the fate of two taste and odour compounds, i.e., geosmin and 2-methylisoborneol, in drinking water. The objective is to provide in situ definitive evidence for the relative importance of adsorption and biodegradation of these compounds in Granular Activated Carbon (GAC) beds.