Evaluation of ethyl tert-butyl ether biodegradation in a contaminated aquifer by compound specific isotope analysis and in situ microcosms

Ethyl tert-butyl ether (ETBE) is an upcoming groundwater pollutant in Europe whose environmental fate has been less investigated thus far. In the present study, we investigated the in situ biodegradation of ETBE in a fuel-contaminated aquifer using compound-specific stable isotope analysis (CSIA) an...

Descripción completa

Detalles Bibliográficos
Autores: Bombach, P., Nägele, N., Rosell, Mònica, Vicente Velilla, E., Richnow, H.H., Fischer, A.
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2015
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/163499
Acceso en línea:https://hdl.handle.net/2445/163499
Access Level:acceso abierto
Palabra clave:Biodegradació
Isòtops estables en ecologia
Contaminació de l'aigua
Biodegradation
Stable isotopes in ecological research
Water pollution
Descripción
Sumario:Ethyl tert-butyl ether (ETBE) is an upcoming groundwater pollutant in Europe whose environmental fate has been less investigated thus far. In the present study, we investigated the in situ biodegradation of ETBE in a fuel-contaminated aquifer using compound-specific stable isotope analysis (CSIA) and in situ microcosms in combination with total lipid fatty acid (TLFA)-stable isotope probing (SIP). In a first field investigation, CSIA revealed no significant carbon isotope fractionation but low hydrogen isotope fractionation of up to +14 ¿ along the prevailing anoxic ETBE plume suggesting biodegradation of ETBE. Ten months later, oxygen injection was conducted to enhance the biodegradation of petroleum hydrocarbons (PH) at the field site. Within the framework of this remediation measure, in situ microcosms loaded with [13C6]-ETBE (BACTRAP®s) were exposed for 119 days in selected groundwater wells to assess the biodegradation of ETBE by TLFA-SIP under the following conditions: (i) ETBE as main contaminant; (ii) ETBE as main contaminant subjected to oxygen injection; (iii) ETBE plus other PH; (iv) ETBE plus other PH subjected to oxygen injection. Under all conditions investigated, significant 13C-incorporation into microbial total lipid fatty acids extracted from the in situ microcosms was found, providing clear evidence of ETBE biodegradation.