title: Penta- and 2,4,6-tri-chlorophenol biodegradation during municipal solid waste anaerobic digestion.
abstract: In this study isotopic tracing using (13)C labelled pentachlorophenol (PCP) and 2,4,6-trichlorophenol (2,4,6-TCP) is proposed as a tool to distinguish the loss of PCP and 2,4,6-TCP due to biodegradation from other physical processes. This isotopic approach was applied to accurately assess in situ PCP and 2,4,6-TCP degradation under methanogenic conditions in several microcosms made up of household waste. These microcosms were incubated in anaerobic conditions at 35°C (mesophilic) and 55°C (thermophilic) without agitation. The volume of biogas produced (CH4 and CO2), was followed for a period of 130 days. At this stage of stable methanogenesis, (13)C6-PCP and (13)C6-2,4,6-TCP were introduced anaerobically in microcosms and its monitoring at mesophilic and thermophilic conditions was performed in parallel by gas chromatography mass spectrometry (GC-MS) and gas chromatography isotope-ratio mass spectrometry (GC-IRMS). This study proved the almost total dechlorination of bioavailable PCP and 2,4,6-TCP into 4-CP at 35°C. Nevertheless, high rate adsorption in particular materials of the two compounds was observed. Furthermore, Carbon-13 Nuclear Magnetic Resonance ((13)C-NMR) Spectroscopy analysis of (13)C labelled 2,4,6-TCP mesophilic incubations showed the partial mineralization of 4-CP at 35°C to acetate and then to HCO(3-). Consequently, NMR results confirm the biogas isotopic results indicating the mineralization of (13)C labelled 2,4,6-TCP into (13)C (CH4 and CO2). Concerning (13)C labelled PCP mesophilic incubations, the isotopic composition of the biogas still natural until the day 262. In contrast, no dechlorination was observed at 55°C. Thus PCP and 2,4,6-TCP were persistent in thermophilic conditions.
authors.affiliation: Hydrosystems and Bioprocesses Research Unit, IRSTEA, 1 rue Pierre-Gilles de Gennes, CS 10030, F-92761 Antony Cedex, France; Laboratory of Heteroatom Organic Chemistry, Department of Chemistry, Faculty of Sciences of Bizerte, University of Carthage, 7021 Zarzouna, Tunisia; Material, Treatment and Analysis Laboratory, LR 15INRAP 03, National Institute of Research and Physicochemical Analysis, 2020 Sidi Thabet, Tunisia. Electronic address: intilim@yahoo.fr.
authors.forename: Intissar
authors.initials: I
authors.lastname: Limam
authors.affiliation: Hydrosystems and Bioprocesses Research Unit, IRSTEA, 1 rue Pierre-Gilles de Gennes, CS 10030, F-92761 Antony Cedex, France; National Center for Nuclear Sciences and Technologies, 2020 Sidi Thabet, Tunisia.
authors.forename: Rim Driss
authors.initials: RD
authors.lastname: Limam
authors.affiliation: Material, Treatment and Analysis Laboratory, LR 15INRAP 03, National Institute of Research and Physicochemical Analysis, 2020 Sidi Thabet, Tunisia.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Mezni
authors.affiliation: Hydrosystems and Bioprocesses Research Unit, IRSTEA, 1 rue Pierre-Gilles de Gennes, CS 10030, F-92761 Antony Cedex, France.
authors.forename: Angéline
authors.initials: A
authors.lastname: Guenne
authors.affiliation: Hydrosystems and Bioprocesses Research Unit, IRSTEA, 1 rue Pierre-Gilles de Gennes, CS 10030, F-92761 Antony Cedex, France.
authors.forename: Céline
authors.initials: C
authors.lastname: Madigou
authors.affiliation: Laboratory of Heteroatom Organic Chemistry, Department of Chemistry, Faculty of Sciences of Bizerte, University of Carthage, 7021 Zarzouna, Tunisia.
authors.forename: Mohamed Ridha
authors.initials: MR
authors.lastname: Driss
authors.affiliation: Hydrosystems and Bioprocesses Research Unit, IRSTEA, 1 rue Pierre-Gilles de Gennes, CS 10030, F-92761 Antony Cedex, France.
authors.forename: Théodore
authors.initials: T
authors.lastname: Bouchez
authors.affiliation: Hydrosystems and Bioprocesses Research Unit, IRSTEA, 1 rue Pierre-Gilles de Gennes, CS 10030, F-92761 Antony Cedex, France. Electronic address: Laurent.mazeas@irstea.fr.
authors.forename: Laurent
authors.initials: L
authors.lastname: Mazeas
mesh_terms: D000327:Adsorption; D000693:Anaerobiosis; D001105:Archaea / Q000378:metabolism; D001419:Bacteria / Q000378:metabolism; D001673:Biodegradation, Environmental; D019149:Bioreactors; D002245:Carbon Dioxide / Q000032:analysis; D002247:Carbon Isotopes; D002733:Chlorophenols / Q000378:metabolism*; D002947:Cities; D008697:Methane / Q000032:analysis / Q000096:biosynthesis; D010416:Pentachlorophenol / Q000378:metabolism*; D062611:Solid Waste; D013696:Temperature; D018505:Waste Management
chemical_list: D002247:Carbon Isotopes; D002733:Chlorophenols; D062611:Solid Waste; D002245:Carbon Dioxide; D010416:Pentachlorophenol; C024564:2,4,6-trichlorophenol; D008697:Methane
keywords: (13)C NMR Spectroscopy; 2,4,6-Trichlorophenol; Gas chromatography-isotopic mass spectrometry; Headspace solid-phase microextraction; Municipal solid waste anaerobic digestion; Pentachlorophenol