Effects of the Nonionic Surfactant Tween 80 on Microbial Reductive Dechlorination of Chlorinated Ethenes
- 30 January 2007
- journal article
- research article
- Published by American Chemical Society (ACS) in Environmental Science & Technology
- Vol. 41 (5), 1710-1716
- https://doi.org/10.1021/es061926v
Abstract
Recent field studies have indicated synergistic effects of coupling microbial reductive dechlorination with physico chemical remediation (e.g., surfactant flushing) of dense nonaqueous phase liquid (DNAPL) source zones. This study explored chlorinated ethene (e.g., tetrachloroethene [PCE]) dechlorination in the presence of 50−5000 mg/L Tween 80, a nonionic surfactant employed in source zone remediation. Tween 80 did not inhibit dechlorination by four pure PCE-to-cis-1,2-dichloroethene (cis-DCE) or PCE-to-trichloroethene (TCE) dechlorinating cultures. In contrast, cis-DCE-dechlorinating Dehalococcoides isolates (strain BAV1 and strain FL2) failed to dechlorinate in the presence of Tween 80. Bio-Dechlor INOCULUM (BDI), a PCE-to-ethene dechlorinating consortium, produced cis-DCE in the presence of Tween 80, further suggesting that Tween 80 inhibits dechlorination by Dehalococcoides organisms. Quantitative real-time PCR analysis applied to BDI revealed that the number of Dehalococcoides cells decayed exponentially (R 2 = 0.85) according to the Chick−Watson disinfection model (pseudo first-order decay rate of 0.13 ± 0.02 day-1) from an initial value of 6.6 ± 1.5 × 108 to 1.3 ± 0.8 × 105 per mL of culture after 58 days of exposure to 250 mg/L Tween 80. Although Tween 80 exposure prevented ethene formation and reduced Dehalococcoides cell numbers, Dehalococcoides organisms remained viable, and dechlorination activity past cis-DCE was recovered following the removal of Tween 80. These findings suggest that sequential Tween 80 flushing followed by microbial reductive dechlorination is a promising strategy for remediation of chlorinated ethene-impacted source zones.Keywords
This publication has 30 references indexed in Scilit:
- Biological Enhancement of Tetrachloroethene Dissolution and Associated Microbial Community ChangesEnvironmental Science & Technology, 2006
- Quantitative PCR Targeting 16S rRNA and Reductive Dehalogenase Genes Simultaneously Monitors Multiple Dehalococcoides StrainsApplied and Environmental Microbiology, 2006
- Bioaugmentation for chlorinated ethene detoxification: Bioaugmentation and molecular diagnostics in the bioremediation of chlorinated ethene-contaminated sitesIndustrial Biotechnology, 2005
- Pilot-Scale Demonstration of Surfactant-Enhanced PCE Solubilization at the Bachman Road Site. 2. System Operation and EvaluationEnvironmental Science & Technology, 2005
- Impacts of Co-Solvent Flushing on Microbial Populations Capable of Degrading TrichloroethyleneEnvironmental Health Perspectives, 2005
- Stimulated Microbial Reductive Dechlorination following Surfactant Treatment at the Bachman Road SiteEnvironmental Science & Technology, 2004
- A Gene from the Mesophilic BacteriumDehalococcoides ethenogenesEncodes a Novel Mannosylglycerate SynthaseJournal of Bacteriology, 2004
- Delta-wing function of webbed feet gives hydrodynamic lift for swimming propulsion in birdsNature, 2003
- A Framework for Assessing Risk Reduction Due to DNAPL Mass Removal from Low‐Permeability SoilsGroundwater, 1997
- Measurement of Henry's law constants for C1 and C2 chlorinated hydrocarbonsEnvironmental Science & Technology, 1987