title: Studies on atmospheric degradation of diazinon in the EUPHORE simulation chamber.
abstract: The gas phase atmospheric degradation of diazinon has been investigated at the large outdoor European Photoreactor (EUPHORE) in Valencia, Spain. The rate constant for reaction of diazinon with OH radicals was measured using a conventional relative rate method with di-n-buthylether as reference compound being k = (3.5 ± 1.2) × 10⁻¹¹ cm³ molecule⁻¹ s⁻¹ at 302 ± 10 K and atmospheric pressure. The available evidence indicates that tropospheric degradation of diazinon is mainly controlled by reaction with OH radicals, and that the tropospheric lifetime with respect to the OH reaction is estimated to be around 4h whereas its lifetime with respect to the photolysis is higher than 1d under our conditions. Significant aerosol formation was observed following the reaction of diazinon with OH radicals, and the main carbon-containing products detected in the particle phase were hydroxydiazinon, hydroxydiazoxon and 2-isopropyl-6-methyl-pyrimidinyl-4-ol.
authors: Instituto Universitario CEAM-UMH, C/Charles R. Darwin 14, Parque Tecnológico, 46980 Paterna, Valencia, Spain. amalia@ceam.es
authors: Amalia
authors: A
authors: Muñoz
authors: Annaïg Le
authors: AL
authors: Person
authors: Stéphane Le
authors: SL
authors: Calvé
authors: Abdelwahid
authors: A
authors: Mellouki
authors: Esther
authors: E
authors: Borrás
authors: Véronique
authors: V
authors: Daële
authors: Teresa
authors: T
authors: Vera
mesh_terms: D000393:Air Pollutants / Q000737:chemistry*; D001272:Atmosphere / Q000737:chemistry; D003976:Diazinon / Q000737:chemistry*; D005740:Gases / Q000737:chemistry; D017665:Hydroxyl Radical / Q000737:chemistry; D007306:Insecticides / Q000737:chemistry*; D013030:Spain
chemical_list: D000393:Air Pollutants; D005740:Gases; D007306:Insecticides; D017665:Hydroxyl Radical; D003976:Diazinon