title: Development of a treatment solution for reductive dechlorination of hexachloro-1,3-butadiene in vadose zone soil.
abstract: The biodegradation of chlorinated organics in vadose zone soils is challenging owing to the presence of oxygen, which inhibits reductive dehalogenation reactions and consequently the growth of dehalorespiring microbes. In addition, the hydraulic conductivity of vadose zone soils is typically high, hence attempts to remediate such zones with biostimulation solutions are often unsuccessful due to the short residence times for these solutions to act upon the native bacterial community. In this study we have identified sodium alginate as a hydrogel polymer that can be used to increase the residence time of a nutrient solution in an unsaturated sandy soil. Additionally we have identified neutral red as a redox active compound that can catalyse the reductive dechlorination of the chlorinated organic hexachloro-1,3-butadiene by activated sludge fed with lactate and acetate. Finally we have shown that a nutrient solution amended with neutral red and sodium alginate can lower the redox potential and reduce hexachloro-1,3-butadiene concentrations in a contaminated vadose zone soil.
authors.affiliation: Centre for Marine Bio-Innovation, The University of New South Wales, Sydney, NSW, Australia.
authors.forename: Lachlan H
authors.initials: LH
authors.lastname: Yee
authors.forename: Vibeke
authors.initials: V
authors.lastname: Aagaard
authors.forename: Angela
authors.initials: A
authors.lastname: Johnstone
authors.forename: Matthew
authors.initials: M
authors.lastname: Lee
authors.forename: Staffan J
authors.initials: SJ
authors.lastname: Kjelleberg
authors.forename: Mike
authors.initials: M
authors.lastname: Manefield
mesh_terms: D000464:Alginates / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects / Q000254:growth & development; D055162:Biocatalysis / Q000187:drug effects; D001673:Biodegradation, Environmental / Q000187:drug effects; D002070:Butadienes / Q000378:metabolism*; D002712:Chlorides / Q000378:metabolism; D058645:Denaturing Gradient Gel Electrophoresis; D052918:Environmental Restoration and Remediation / Q000379:methods*; D020723:Glucuronic Acid / Q000494:pharmacology; D054879:Halogenation / Q000187:drug effects*; D006603:Hexuronic Acids / Q000494:pharmacology; D009499:Neutral Red / Q000378:metabolism; D009566:Nitrates / Q000378:metabolism; D012987:Soil / Q000737:chemistry*; D012996:Solutions / Q000494:pharmacology*; D013431:Sulfates / Q000378:metabolism; D013997:Time Factors; D014783:Viscosity / Q000187:drug effects
chemical_list: D000464:Alginates; D002070:Butadienes; D002712:Chlorides; D006603:Hexuronic Acids; D009566:Nitrates; D012987:Soil; D012996:Solutions; D013431:Sulfates; D009499:Neutral Red; D020723:Glucuronic Acid; C001335:hexachlorobutadiene