NERC Priortiy Area - WATER - Predicting the natural attenuation of ethyl-tertiary-butyl-ether (ETBE) in groundwater

NERC 优先领域 - 水 - 预测地下水中乙基叔丁基醚 (ETBE) 的自然衰减

• 批准号: NE/I019162/1
• 负责人: Steven Thornton
• 金额: $ 8.58万
• 依托单位: University of Sheffield
• 依托单位国家: 英国
• 项目类别: Training Grant
• 财政年份: 2011
• 资助国家: 英国
• 起止时间: 2011 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FI019162%2F1
• 关键词: NERC; Priortiy; Area; WATER; Predicting

Ether oxygenate compounds have been used as additives in unleaded gasoline since the 1980s to enhance combustion and reduce emissions. In Europe the ether oxygenate compound ethyl-tertiary-butyl-ether (ETBE) is now being introduced for this purpose. Although ETBE is believed to have a similar environmental hazard profile to other ether oxygenates that have previously been used in unleaded gasoline, there is insufficient information on the fate of ETBE in the subsurface environment. This is needed to evaluate the environmental risk from a release of ETBE-amended gasoline to groundwater, and to devise appropriate management and remediation strategies. Previous research suggests that new synthetic chemicals (of which ETBE is one) that are released into the environment can persist because microorganisms lack the metabolic potential to biodegrade them. However there is evidence that over time, biodegradation pathways can develop naturally to metabolise such chemicals. This seems to occur through complex interactions between different populations of microorganisms in communities and mechanisms which allow transfer of genes between species to support such biodegradation. It is necessary to understand these relationships to identify conditions when biodegradation of ETBE will occur in groundwater and to qualify the environmental risk of using ETBE-amended gasoline in the UK and Europe. This project will provide scientific evidence to help address these issues. It will deduce the microbiological controls on the biodegradation potential of ETBE in groundwater under different environmental conditions. This will help identify conditions in groundwater where ETBE biodegradation may occur and whether natural attenuation can be an effective risk management strategy for groundwater contaminated by gasoline containing ETBE. Laboratory studies will be used to assess the effect of different environmental factors on ETBE biodegradation rates in groundwater under representative controlled conditions. These factors will include (i) the availability of different electron acceptors for biodegradation, (ii) ETBE concentration required to support biodegradation or that which may inhibit it, (iii) nutrient limitations, (iv) interaction of ETBE with other organic compounds and potential carbon sources in gasoline which may control biodegradation, and (v) the presence and metabolic function of microorganisms responsible for such biodegradation. Groundwater and aquifer sediment samples from uncontaminated and ETBE-contaminated sites will be used in these experiments, which will be manipulated as the biodegradation behaviour evolves to explore interactions between the microbial communities, for detailed interpretation. Novel microbiological techniques, which include state-of-the-art molecular analysis, will be used to investigate the microbiological processes and relationships between different populations of microorganisms responsible for ETBE biodegradation under the range of conditions examined. The project will be carried out in the Groundwater Protection and Restoration Group at the University of Sheffield, as a CASE studentship sponsored by CONCAWE, the European Oil Industry Association for the Environment and Health, which has responsibility to advise its membership and policy makers on the safety and environmental performance of the industry. It will be linked with a new EU Marie Curie Initial Training Network ('ADVOCATE'), which will be established at Sheffield in 2011 to provide scientific and practical research training to young scientists in the field of sustainable in situ remediation for contaminated land and groundwater.

自20世纪80年代以来，醚类含氧化合物一直被用作无铅汽油的添加剂，以增强燃烧和减少排放。在欧洲，乙醚氧合化合物乙基叔丁基醚（ETBE）目前正为此目的而引入。虽然ETBE被认为与以前在无铅汽油中使用的其他醚氧化物具有相似的环境危害概况，但关于ETBE在地下环境中的命运的信息不足。这对于评价将经etbe修正的汽油排放到地下水中的环境风险以及制定适当的管理和补救战略是必要的。先前的研究表明，释放到环境中的新的合成化学物质（ETBE就是其中之一）可以持续存在，因为微生物缺乏生物降解它们的代谢潜力。然而，有证据表明，随着时间的推移，生物降解途径可以自然发展，以代谢这些化学物质。这似乎是通过群落中不同微生物种群之间的复杂相互作用以及允许物种之间基因转移以支持这种生物降解的机制发生的。有必要了解这些关系，以确定地下水中ETBE生物降解的条件，并确定在英国和欧洲使用ETBE改性汽油的环境风险。这个项目将提供科学证据来帮助解决这些问题。揭示了不同环境条件下微生物对地下水中ETBE生物降解潜力的控制作用。这将有助于确定地下水中可能发生ETBE生物降解的条件，以及自然衰减是否可以成为含有ETBE的汽油污染地下水的有效风险管理策略。在具有代表性的受控条件下，将利用实验室研究来评估不同环境因素对地下水中ETBE生物降解率的影响。这些因素将包括(i)生物降解所需的不同电子受体的可用性，（ii）支持生物降解或可能抑制生物降解所需的ETBE浓度，（iii）营养限制，（iv） ETBE与其他有机化合物和汽油中可能控制生物降解的潜在碳源的相互作用，以及(v)负责这种生物降解的微生物的存在和代谢功能。这些实验将使用来自未受污染和etbe污染地点的地下水和含水层沉积物样本，随着生物降解行为的演变，这些样本将被操纵，以探索微生物群落之间的相互作用，以进行详细的解释。新的微生物学技术，其中包括最先进的分子分析，将用于研究微生物过程和负责ETBE生物降解的不同微生物种群之间的关系，在检查的条件范围内。该项目将在谢菲尔德大学地下水保护和恢复小组进行，作为由欧洲石油工业环境与健康协会（CONCAWE）赞助的CASE学生，该协会负责就该行业的安全和环境绩效向其成员和决策者提供咨询意见。它将与一个新的欧盟居里夫人初始培训网络（“ADVOCATE”）联系起来，该网络将于2011年在谢菲尔德建立，为受污染土地和地下水的可持续原位修复领域的年轻科学家提供科学和实践研究培训。