Natural Attenuation and Enhanced Biodegradation of Methyl tert-Butyl Ether in Anoxic Aquifers

CBET 1335824 Max M. Haggblom 罗格斯大学甲基叔丁基醚 (MTBE) 是一种有趣的地下水污染物。 MTBE是一种合成化学品，没有天然来源，其生物降解对微生物来说是一个挑战。经过几十年的广泛使用，MTBE 已成为最常检测到的地下水污染物之一，由于其在环境中的持久性，需要进行修复。这项研究的总体假设是，长期 MTBE 污染将使厌氧微生物群落丰富，这些微生物群落能够利用这种化合物作为碳和能源的来源。前期研究表明，MTBE降解可以在不同的缺氧条件下发生，并且可能是缺氧环境中的一个重要过程。然而，人们对能够利用 MTBE 的细菌种类仍知之甚少，对其生物降解机制也知之甚少。该研究项目旨在阐明缺氧地下环境中介导 MTBE 降解的细菌活性。将鉴定负责受污染含水层和沉积物中 MTBE 转化/降解的新型微生物及其基因，以便开发监测环境中 MTBE 自然衰减和增强生物降解的工具。尽管目前已广泛禁止使用 MTBE 作为燃料含氧化合物，但含水层和饮用水源污染的问题仍然存在。 MTBE 具有非常强烈的类似松节油的味道和气味，只能以非常低的水平存在于饮用水中。长期吸入或口服接触 MTBE 对人类健康的影响尚不清楚。人们越来越需要开发有效的技术来修复受 MTBE 污染的场地。监测工具对于了解微生物过程以及修复如何受到不同修正案或其他工程方法的影响至关重要。该项目将产生新的方法来评估和刺激生物修复，并记录自然衰减方法中 MTBE 的原位生物降解情况。多种自然过程控制羽流迁移并降低 MTBE 浓度。在这些过程中，生物降解是以可持续方式减少环境中污染物质量最有效的方法。一个关键的挑战是准确评估原位修复技术的效率。从研究中获得的基础微生物和环境工程知识将填补我们对 MTBE 在环境中的命运和转化的理解方面的主要知识空白。通过新兴的 MTBE 环境分子诊断技术实施现场评估，可以通过更可持续的修复实践来节省成本，帮助选择现场方法，从而缩短时间，并提供信息以实现更合理的现场修复方法。

CBET 1335824 Max M. HaggblomRutgers UniversityMethyl tert-butyl ether (MTBE) is an intriguing groundwater pollutant. MTBE is a synthetic chemical with no natural sources and its biodegradation is a challenge to microorganisms. As a consequence of several decades of extensive use MTBE has become one of the most frequently detected groundwater contaminants, requiring remediation due to its persistence in the environment. The overall hypothesis of this research is that long-term MTBE contamination will enrich for anaerobic microbial communities that are capable of utilizing this compound as a source of carbon and energy. Previous research has demonstrated that MTBE degradation can occur under different anoxic conditions, and may be an important process in anoxic environments. However, little is still known about the bacterial species that can utilize MTBE and the biodegradation mechanisms are poorly understood. The research project seeks to elucidate the activity of bacteria that mediate degradation of MTBE in anoxic subsurface environments. Novel microorganisms and their genes responsible for transformation/degradation of MTBE in contaminated aquifers and sediments will be identified in order to develop tools for monitoring natural attenuation and enhanced biodegradation of MTBE in the environment. Although the use of MTBE as a fuel oxygenate has now been widely banned, problems with contaminated aquifers and drinking water sources persist. MTBE has a very strong turpentine-like taste and smell and can only be tolerated in drinking water at very low levels. The human-health effects of long-term inhalation or oral exposures to MTBE are unknown. There has been an increasing need in the development of effective technologies to remediate MTBE-contaminated sites. Monitoring tools are critical to gaining an understanding of how microbial processes, and thus remediation, are affected by different amendments or other engineering approaches. This project will yield novel approaches to assess and stimulate bioremediation and to document in situ MTBE biodegradation in natural attenuation approaches. A variety of natural processes control plume migration and reduce MTBE concentration. Among these processes, biodegradation is the most effective in reducing the mass of contaminant in the environment in a sustainable way. A key challenge is to accurately assess the efficiency of the remediation techniques in situ. The fundamental microbiological and environmental engineering knowledge gained from the research will fill major knowledge gaps in our understanding of fate and transformation of MTBE in the environment. Implementation of site assessment via emerging environmental molecular diagnostics for MTBE could lead to cost-savings through more sustainable remediation practices, aid choice of site approaches that lead to shortened timelines, and provide information to allow a more rational approach for site remediation.