Collaborative Research: Treatment of Cyanotoxins by UV/Chlorine: Optimizing Removal While Developing Strategies to Minimize Disinfection Byproducts and Toxicity

合作研究：紫外线/氯处理蓝藻毒素：优化去除同时制定尽量减少消毒副产物和毒性的策略

• 批准号: 2042016
• 负责人: Susan Richardson
• 金额: $ 15万
• 依托单位: University of South Carolina at Columbia
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-01 至 2025-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2042016&HistoricalAwards=false
• 关键词: Collaborative; Research; Treatment; Cyanotoxins; UV

Harmful algal blooms (HABs) occur when harmful algae grow out of control in surface water systems including lakes, rivers, and estuaries. This causes a large decrease in oxygen levels in the water and the release of toxic chemicals commonly referred to as cyanotoxins. These toxins can cause illness and death in fish, animals, and humans. HABs are increasing in frequency and severity throughout the world and are often triggered by excessive nutrients (phosphorus and nitrogen). In recent years, severe HABs have occurred in more than 20 states throughout the United States. However, traditional drinking water treatment processes (coagulation, flocculation, sedimentation, and chlorination) cannot fully remove cyanotoxins (to below the concentrations considered as toxic by federal and state agencies) especially during massive HAB events. The overarching goal of this collaborative research project is to evaluate and optimize the performance of a new water treatment process that combines UV light with chlorine (UV/chlorine) to break down cyanotoxins present in drinking water. The successful completion of this project will benefit society through the development of new fundamental knowledge that could lead to a new water treatment technology (UV/Chlorine) for the removal cyanotoxins to safe levels while minimizing the formation of toxic disinfection by-products (DBPs). Further benefits to society will be achieved through outreach and educational activities including 1) workshops and interactions with drinking water treatment professionals and relevant stakeholders, 2) course development, and 3) the mentoring of three doctoral students. Cyanotoxins, released by cyanobacteria during harmful algae blooms (HABs), are major threats to human and ecosystem health in the United Stated and worldwide. Various water treatment technologies, including sorption with granular activated carbon, membrane filtration, chlorination, ozonation, and advanced oxidation processes (AOPs), have shown potential to remove or degrade cyanotoxins. However, cellular lysis can occur during treatment thus increasing exposure to toxins from treated drinking water. In addition, toxic disinfection by-products (DBPs) might be generated when disinfectants such as chlorine react with cyanotoxins and/or algal/planktonic organic matter. Thus, a detailed and careful examination of cyanotoxin degradation during water treatment is critically needed to ensure safe drinking water for the public. The overarching goals of this project are to evaluate the performance of UV/chlorine treatment to degrade cyanotoxins in drinking water sources and elucidate the mechanisms of DBP formation and toxicity under relevant process and environmental conditions. To advance these goals, the collaborative research team proposes to 1) investigate the degradation of two common classes of cyanotoxins (microcystins and cylindrospermopsin) along with a group of 70 related DBPs (including regulated and priority unregulated DBPs); 2) evaluate the role of process conditions (i.e., radiation dose and wavelength, chlorine dose) and water quality parameters (algal organic matter, presence of halides, and solution pH) on degradation efficiency, and 3) determine the reaction kinetics, formation pathways of transformation products including DBPs, and their potential toxicity to human and ecosystems using transcriptomics. The successful completion of this project has potential for transformative impact through the development of new fundamental knowledge about the UV/Chlorine water treatment process that could lead to the effective removal cyanotoxins from drinking water sources to safe levels while minimizing the formation of toxic DBPs.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.

当有害藻类在包括湖泊，河流和河口在内的地表水系统中失控时，发生有害的藻华（HAB）。这会导致水中的氧气水平大大降低，并且通常称为氰毒素的有毒化学物质的释放。这些毒素会导致鱼类，动物和人类的疾病和死亡。 HAB在全球范围内的频率和严重程度都在增加，并且通常是由过量的营养（磷和氮）触发的。近年来，美国20多个州发生了严重的HAB。但是，传统的饮用水处理过程（凝结，絮凝，沉积和氯化）无法完全去除氰毒素（低于联邦和州机构认为是有毒的浓度），尤其是在大规模的HAB事件中。该协作研究项目的总体目标是评估和优化新的水处理过程的性能，该过程将紫外线与氯（UV/氯）结合在一起，以分解饮用水中存在的氰毒素。该项目的成功完成将通过发展新的基本知识来使社会受益，这可能会导致新的水处理技术（UV/氯）去除氰毒素达到安全水平，同时最大程度地减少有毒消毒副产品（DBP）的形成。通过外展和教育活动，包括1）讲习班和与饮用水治疗专业人员和相关利益相关者的互动，2）课程发展以及3）指导三个博士生的讲习班和互动来实现对社会的进一步好处。 蓝细菌在有害藻类开花（HABS）期间发布的蓝细菌是对联合国人类和生态系统健康的主要威胁。各种水处理技术，包括用颗粒活性碳吸附，膜过滤，氯化，臭氧和晚期氧化过程（AOPS）（AOPS），已显示出去除或降解氰毒素的潜力。然而，在治疗过程中可能会发生细胞裂解，从而增加了处理过的饮用水对毒素的暴露。此外，当氯与氰毒素和/或藻类/膨胀/浮游有机物反应时，可能会产生有毒的消毒副产品（DBP）。因此，非常需要对水处理期间的氰毒素降解进行详细而仔细的检查，以确保为公众提供安全的饮用水。该项目的总体目标是评估紫外线/氯处理的性能，以降解饮用水源中的氰毒素，并阐明在相关过程和环境条件下DBP形成和毒性的机制。为了促进这些目标，协作研究小组建议1）研究两种常见类别的氰毒素（微囊蛋白酶和cylindrospermopsin）的降解以及一组70个相关的DBP（包括受监管和优先级和不受监管的DBP）； 2）评估过程条件（即辐射剂量和波长，氯剂量）和水质参数（藻类有机物，卤化物的存在和溶液pH）对降解效率的作用，以及3）确定反应动力学，包括DBPS的转化产物的形成途径，包括DBPS的毒素以及其对人类对人类和生态系统的潜在毒素的形成途径。通过发展有关紫外线/氯处理过程的新基本知识，该项目的成功完成可能会产生变革性的影响，这可能导致有效的去除含水源从饮用水源到安全水平，同时最大程度地减少有毒DBP的形成，这是通过评估众所周知的Intelligia and Intelligial and Intellitial and Intellitial and Intfactial and Intellitial and Interviatial and Intervisial and Infcessiation and Intfactial and Inthlib and Intervisial and Intfactial and Inthernitial this奖项。