Collaboration on Oxidative Elimination of Cyanotoxins by Ferrates(VI, V, and IV)

1236331/1235636/ O’shea /Dionysiou全世界饮用水水库中的蓝藻（通常被称为蓝绿藻）对人类健康的影响令人严重关切。近年来，蓝藻有害藻华（Cyano-HABs）在五大湖和佛罗里达流域尤其成问题。五大湖的面积占世界的五分之一。它为2400多万加拿大和美国公民提供饮用水。在该地区，有报告称，至少在安大略湖的6个地点，伊利湖的7个地点，休伦湖的3个地点和密歇根湖的2个地点发生了蓝藻-赤潮事件。蓝藻细菌产生味道和气味化合物，但由于释放出强效的水溶性有毒化合物，称为蓝藻毒素（即肝毒素，皮肤毒素，神经毒素），因此对环境造成严重危害。微囊藻毒素（MCs）是一种肝毒性环肽毒素，是分布最广的蓝藻毒素。随着全球气候变化的发生，预计氰化有害藻华的频率和毒性都会增加。有害藻华的增加和MCs对健康的负面影响导致迫切需要确定有效的水处理方法，以消除供水中的蓝藻毒素。可以采用物理方法去除MCs，但这种方法不会破坏毒素，而且相关的治疗费用通常令人望而却步。蓝藻毒素氧化转化为毒性较低的副产物为污染水的处理提供了一个有吸引力的选择。传统的氧化技术，如氯化、紫外线和臭氧化通常不具有成本效益。此外，有毒副产物的形成，包括溴酸盐和消毒副产物是主要的缺点。高价铁基四氧化合物高铁酸盐(FeVIO42-, Fe(VI), FeVO43-, Fe(V)和FeIVO43-， （Fe(IV)）是新兴的水处理消毒剂和有前途的氧化剂，可以解决与当前处理技术相关的问题。铁(V)和铁（IV）是比铁（VI）更强的氧化剂，可以有效地处理耐氯微生物和毒素。本研究将探讨不同高铁酸盐在自然水条件下对毒素的降解而不产生有毒副产物。此外，还将开发一种新型光催化剂，该催化剂在Fe（VI）存在的情况下，在太阳光和可见光照射下有效降解蓝藻毒素。该研究有望为高铁酸盐工艺和高铁酸盐基太阳能光催化水处理工艺的合理优化策略的制定提供必要的基本机制理解。该合作项目将在高铁酸盐水净化技术领域做出重大贡献。开发具有成本效益的水净化技术，特别是小型处理厂作为应对藻华季节性问题的技术，将对保护人类健康产生重大影响。此外，对高铁酸盐化学的分子理解将有助于阐明高价铁在许多关键生物过程中的参与，包括衰老和疾病。研究活动将通过由本科生、研究生、博士后和pi组成的研究团队的互动，促进和促进教学、指导、培训和学习。私立学校将招收女性和少数民族学生。外展活动将为本科生和高中生提供机会，包括来自代表性不足群体的学生，参加环境工程和科学方面的培训和研究，其中包括水监测和蓝藻鉴定。

1236331/1235636/1235803/1236209 Sharma/Westrick/O'Shea/Dionysiou There is serious concern over the human health impacts of cyanobacteria, commonly referred to as blue green algae, in drinking water reservoirs worldwide. Cyanobacterial harmful algal blooms (Cyano-HABs) have been especially problematic in the Great Lakes and Florida Watersheds in recent years. The Great Lakes contain one-fifth of the world?s freshwater and provide drinking water to over 24 million Canadian and U.S. citizens. In this region, there are reports of cyano-HABs events at least at six locations in Lake Ontario, seven locations in Lake Erie, three locations in Lake Huron, and two locations in Lake Michigan. Cyanobacteria produce taste and odour compounds but pose a serious environmental hazard because of the release of potent water soluble toxic compounds, called cyanotoxins (i.e., hepatotoxins, dermatotoxins, neurotoxins). Microcystins (MCs), which are hepatotoxic cyclic peptide toxins, are the most widespread cyanotoxins. As global climate change occurs, cyano-HABs are predicted to increase in both frequency and toxicity. The increase in HABs and the negative health effects of MCs have resulted in an urgent need to identify efficient water treatment methods to eliminate cyanotoxins from water supplies. Physical methods can be employed to remove MCs however such methods do not destroy the toxins and the associated treatment costs are generally prohibitive. Oxidative transformation of cyanotoxins to less toxic by-products offers an attractive option for treatment of contaminated water. Conventional oxidative technologies, such as chlorination, UV, and ozonization are often not cost effective. In addition, the formation of toxic by-products, including bromate and disinfection by products are major drawbacks. High-valent iron-based tetra-oxy compounds, ferrates (FeVIO42-, Fe(VI), FeVO43-, Fe(V) and FeIVO43-, (Fe(IV)) are emerging disinfectants and promising oxidizing agents for water treatment and can address the concerns associated with the current treatment technologies. Fe(V) and Fe(IV) are more powerful oxidant than Fe(VI) and may efficiently treat chlorine resistant microorganisms and toxins. This research will investigate the degradation of toxins by different ferrates under natural water conditions without producing toxic byproducts. Additionally, a novel photocatalyst will be developed which in presence of Fe(VI) under solar light and visible light irradiation will yield efficient degradation of cyanotoxins. The research is expected to provide the fundamental mechanistic understanding necessary for the development of rational strategies for optimizing the ferrate process and ferrate-based solar driven photocatalytic process for water treatment. The collaborative project will make a significant contribution in the field of water purification using ferrate technologies. The development of cost-efficient technologies for water purification, especially for small scale treatment plants as response technologies to the seasonal problems of algal blooms will have a significant implication in protecting human health. Additionally, a molecular understanding of the chemistry of ferrate species will help to elucidate the involvement of high-valent iron species in a number of critical biological processes, including aging and diseases. The research activities will promote and foster teaching, mentoring, training and learning through interactions of a compentent research team composed of undergraduate students, graduate students, postdocs and the PIs. The PIs will recruit females and minority students. Outreach activities will provide opportunities to undergraduate and high school students, including from underrepresented groups, for training and research in environmental engineering and science, which will include water monitoring and cyanobacterial identification.