title: Atmospheric degradation of lindane and 1,3-dichloroacetone in the gas phase. Studies at the EUPHORE simulation chamber.
abstract: The gas-phase degradation of lindane (γ-isomer of hexachlorocyclohexane) towards OH radical was investigated under atmospheric conditions at the large outdoor European simulation chamber (EUPHORE) in Valencia, Spain. The rate coefficient for the reaction of hydroxyl radicals with lindane was measured using a conventional relative rate technique leading to a value of kOH(lindane)=(6.4±1.6)×10(-13) cm(3) molecule(-1) s(-1) at 300±5 K and atmospheric pressure. The results suggest that the tropospheric lifetime of lindane with respect to OH radicals is approximately 20 days. The product distribution studies on the OH-initiated oxidation of lindane provided evidence that the major initial carbon-containing oxidation product is pentachlorocyclohexanone. 1,3-Dichloroacetone was employed as a model compound for pentachlorocyclohexanone, and an investigation of its photolysis and reaction with OH radicals under atmospheric conditions was carried out. The data indicate that the atmospheric degradation of pentachlorocyclohexanone would be relatively rapid, and would not form persistent organic compounds. Theoretical study was also employed to calculate possible degradation pathways. Mechanism for reaction of lindane with OH radicals is proposed, and C-Cl bond cleavage is discussed. OH abstraction is considered to be a reasonable way for Cl to escape during degradation. The atmospheric implications of the use of lindane as an insecticide are discussed.
authors.affiliation: Fundación CEAM, C/Charles R. Darwin, 14, Parque Tecnológico, 46980 Paterna, Valencia, Spain; Atmospheric Pesticide Research group of Valencia, Valencia, Spain.
authors.forename: Teresa
authors.initials: T
authors.lastname: Vera
authors.affiliation: Fundación CEAM, C/Charles R. Darwin, 14, Parque Tecnológico, 46980 Paterna, Valencia, Spain; Atmospheric Pesticide Research group of Valencia, Valencia, Spain.
authors.forename: Esther
authors.initials: E
authors.lastname: Borrás
authors.affiliation: Environment Research Institute, Shandong University, Jinan 250100, PR China.
authors.forename: Jianmin
authors.initials: J
authors.lastname: Chen
authors.affiliation: Atmospheric Pesticide Research group of Valencia, Valencia, Spain; Public Health Laboratory of Valencia-FISABIO, 21, Avenida Catalunya, 46020 Valencia, Spain.
authors.forename: Clara
authors.initials: C
authors.lastname: Coscollá
authors.affiliation: CNRS-ICARE/OSUC, 1C Avenue de la Recherche Scientifique, 45071 Orléans Cedex 2, France.
authors.forename: Véronique
authors.initials: V
authors.lastname: Daële
authors.affiliation: Environment Research Institute, Shandong University, Jinan 250100, PR China; CNRS-ICARE/OSUC, 1C Avenue de la Recherche Scientifique, 45071 Orléans Cedex 2, France.
authors.forename: Abdelwahid
authors.initials: A
authors.lastname: Mellouki
authors.affiliation: Fundación CEAM, C/Charles R. Darwin, 14, Parque Tecnológico, 46980 Paterna, Valencia, Spain; Atmospheric Pesticide Research group of Valencia, Valencia, Spain.
authors.forename: Milagros
authors.initials: M
authors.lastname: Ródenas
authors.affiliation: School of Chemistry and Chemical Biology, University College Dublin, Belfield, Dublin 4, Ireland.
authors.forename: Howard
authors.initials: H
authors.lastname: Sidebottom
authors.affiliation: Environment Research Institute, Shandong University, Jinan 250100, PR China.
authors.forename: Xiaomin
authors.initials: X
authors.lastname: Sun
authors.affiliation: Atmospheric Pesticide Research group of Valencia, Valencia, Spain; Public Health Laboratory of Valencia-FISABIO, 21, Avenida Catalunya, 46020 Valencia, Spain.
authors.forename: Vicent
authors.initials: V
authors.lastname: Yusá
authors.affiliation: Environment Research Institute, Shandong University, Jinan 250100, PR China.
authors.forename: Xue
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Fundación CEAM, C/Charles R. Darwin, 14, Parque Tecnológico, 46980 Paterna, Valencia, Spain; Atmospheric Pesticide Research group of Valencia, Valencia, Spain. Electronic address: amalia@ceam.es.
authors.forename: Amalia
authors.initials: A
authors.lastname: Muñoz
mesh_terms: D000096:Acetone / Q000031:analogs & derivatives* / Q000032:analysis / Q000737:chemistry; D000393:Air Pollutants / Q000032:analysis* / Q000737:chemistry; D001274:Atmospheric Pressure; D002980:Climate; D001556:Hexachlorocyclohexane / Q000032:analysis* / Q000737:chemistry; D017665:Hydroxyl Radical / Q000737:chemistry*; D008962:Models, Theoretical; D010084:Oxidation-Reduction; D010782:Photolysis; D013030:Spain
chemical_list: D000393:Air Pollutants; D000096:Acetone; D017665:Hydroxyl Radical; D001556:Hexachlorocyclohexane; C047675:1,3-dichloroacetone
keywords: Dichloroacetone; EUPHORE; Lindane; Organochlorine insecticides; Photo-oxidation; Tropospheric lifetime