title: Effects of Atmospheric Water on ·OH-initiated Oxidation of Organophosphate Flame Retardants: A DFT Investigation on TCPP.
abstract: Tris(2-chloroisopropyl) phosphate (TCPP), a widely used organophosphate flame retardant, has been recognized as an important atmospheric pollutant. It is notable that TCPP has potential for long-range atmospheric transport. However, its atmospheric fate is unknown, restricting its environmental risk assessment. Herein we performed quantum chemical calculations to investigate the atmospheric transformation mechanisms and kinetics of TCPP initiated by ·OH in the presence of O2/NO/NO2, and the effects of ubiquitous water on these reactions. Results show the H-abstraction pathways are the most favorable for the titled reaction. The calculated gaseous rate constant and lifetime at 298 K are 1.7 × 10-10cm3molecule-1s-1and 1.7 h, respectively. However, when considering atmospheric water, the corresponding lifetime is about 0.5-20.2 days. This study reveals for the first time that water has a negative role in the ·OH-initiated degradation of TCPP by modifying the stabilities of prereactive complexes and transition states via forming hydrogen bonds, which unveils one underlying mechanism for the observed persistence of TCPP in the atmosphere. Water also influences secondary reaction pathways of selected TCPP radicals formed from the primary H-abstraction. These results demonstrate the importance of water in the evaluation of the atmospheric fate of newly synthesized chemicals and emerging pollutants.
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology , Dalian 116024, China.|State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University , Changchun 130117, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Li
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology , Dalian 116024, China.
authors.forename: Jingwen
authors.identifier: http://orcid.org/0000-0002-5756-3336
authors.initials: J
authors.lastname: Chen
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology , Dalian 116024, China.
authors.forename: Hong-Bin
authors.identifier: http://orcid.org/0000-0002-9119-9785
authors.initials: HB
authors.lastname: Xie
authors.affiliation: State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University , Changchun 130117, China.
authors.forename: Yuanhui
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology , Dalian 116024, China.
authors.forename: Deming
authors.initials: D
authors.lastname: Xia
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology , Dalian 116024, China.
authors.forename: Tong
authors.initials: T
authors.lastname: Xu
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology , Dalian 116024, China.
authors.forename: Xuehua
authors.initials: X
authors.lastname: Li
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology , Dalian 116024, China.
authors.forename: Xianliang
authors.initials: X
authors.lastname: Qiao
mesh_terms: D001272:Atmosphere / Q000737:chemistry; D005411:Flame Retardants; D017665:Hydroxyl Radical / Q000737:chemistry; D007700:Kinetics; D010755:Organophosphates; D014867:Water
chemical_list: D005411:Flame Retardants; D010755:Organophosphates; D014867:Water; D017665:Hydroxyl Radical