title: Laboratory and field scale bioremediation of hexachlorocyclohexane (HCH) contaminated soils by means of bioaugmentation and biostimulation.
abstract: Hexachlorocyclohexane (HCH) contaminated soils were treated for a period of up to 64 days in situ (HCH dumpsite, Lucknow) and ex situ (University of Delhi) in line with three bioremediation approaches. The first approach, biostimulation, involved addition of ammonium phosphate and molasses, while the second approach, bioaugmentation, involved addition of a microbial consortium consisting of a group of HCH-degrading sphingomonads that were isolated from HCH contaminated sites. The third approach involved a combination of biostimulation and bioaugmentation. The efficiency of the consortium was investigated in laboratory scale experiments, in a pot scale study, and in a full-scale field trial. It turned out that the approach of combining biostimulation and bioaugmentation was most effective in achieving reduction in the levels of α- and β-HCH and that the application of a bacterial consortium as compared to the action of a single HCH-degrading bacterial strain was more successful. Although further degradation of β- and δ-tetrachlorocyclohexane-1,4-diol, the terminal metabolites of β- and δ-HCH, respectively, did not occur by the strains comprising the consortium, these metabolites turned out to be less toxic than the parental HCH isomers.
authors.affiliation: Department of Zoology, University of Delhi, Delhi, 110007, India.
authors.forename: Nidhi
authors.initials: N
authors.lastname: Garg
authors.affiliation: Department of Zoology, University of Delhi, Delhi, 110007, India.
authors.forename: Pushp
authors.initials: P
authors.lastname: Lata
authors.affiliation: Department of Zoology, University of Delhi, Delhi, 110007, India.
authors.forename: Simran
authors.initials: S
authors.lastname: Jit
authors.affiliation: Department of Zoology, University of Delhi, Delhi, 110007, India.
authors.forename: Naseer
authors.initials: N
authors.lastname: Sangwan
authors.affiliation: Department of Zoology, University of Delhi, Delhi, 110007, India.
authors.forename: Amit Kumar
authors.initials: AK
authors.lastname: Singh
authors.affiliation: Department of Zoology, University of Delhi, Delhi, 110007, India.
authors.forename: Vatsala
authors.initials: V
authors.lastname: Dwivedi
authors.affiliation: Department of Zoology, University of Delhi, Delhi, 110007, India.
authors.forename: Neha
authors.initials: N
authors.lastname: Niharika
authors.affiliation: Department of Zoology, University of Delhi, Delhi, 110007, India.
authors.forename: Jasvinder
authors.initials: J
authors.lastname: Kaur
authors.affiliation: Department of Zoology, University of Delhi, Delhi, 110007, India.
authors.forename: Anjali
authors.initials: A
authors.lastname: Saxena
authors.affiliation: Department of Zoology, University of Delhi, Delhi, 110007, India.
authors.forename: Ankita
authors.initials: A
authors.lastname: Dua
authors.affiliation: Department of Zoology, University of Delhi, Delhi, 110007, India.
authors.forename: Namita
authors.initials: N
authors.lastname: Nayyar
authors.affiliation: Department of Zoology, University of Delhi, Delhi, 110007, India.
authors.forename: Puneet
authors.initials: P
authors.lastname: Kohli
authors.affiliation: Swiss Federal Institute for Aquatic Science and Technology (Eawag), Überlandstrasse133, 8600, Dübendorf, Switzerland.
authors.forename: Birgit
authors.initials: B
authors.lastname: Geueke
authors.affiliation: Swiss Federal Institute for Aquatic Science and Technology (Eawag), Überlandstrasse133, 8600, Dübendorf, Switzerland.
authors.forename: Petra
authors.initials: P
authors.lastname: Kunz
authors.affiliation: Laboratory for Functional Polymers, Swiss Federal Laboratories for Materials Science and Technology (Empa), 8600, Dübendorf, Switzerland.
authors.forename: Daniel
authors.initials: D
authors.lastname: Rentsch
authors.affiliation: EPFL-ENAC-ISTE-LBE, Station 6, 1015, Lausanne, Switzerland.
authors.forename: Christof
authors.initials: C
authors.lastname: Holliger
authors.affiliation: Swiss Federal Institute for Aquatic Science and Technology (Eawag), Überlandstrasse133, 8600, Dübendorf, Switzerland.
authors.forename: Hans-Peter E
authors.initials: HP
authors.lastname: Kohler
authors.affiliation: Department of Zoology, University of Delhi, Delhi, 110007, India. ruplal@gmail.com.
authors.forename: Rup
authors.initials: R
authors.lastname: Lal
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D001673:Biodegradation, Environmental; D001556:Hexachlorocyclohexane / Q000378:metabolism*; D059013:Microbial Consortia; D012989:Soil Pollutants / Q000378:metabolism*
chemical_list: D012989:Soil Pollutants; D001556:Hexachlorocyclohexane
keywords: Bioaugmentation; Biostimulation; Consortium; Hexachlorocyclohexane; Toxicity