Release Time:2019-03-12  Hits:

Indexed by: Journal Article

Date of Publication: 2016-11-15

Journal: SCIENCE OF THE TOTAL ENVIRONMENT

Included Journals: Scopus、PubMed、EI、SCIE

Volume: 571

Page Number: 1105-1114

ISSN: 0048-9697

Key Words: Triphenyl phosphate; Atmospheric oxidation; Mechanism; Ice surface; Computational study

Abstract: Many studies have been performed to evaluate the environmental risk caused by alternative flame retardants (AFRs) of polybrominated diphenyl ethers due to their ubiquitous occurrence in the environment However, as an indispensable component of the environmental risk assessment, the information on atmospheric fate of AFRs is limited although some AFRs have been frequently and highly detected in the atmosphere. Here, a combined quantum chemical method and kinetics modeling were used to investigate atmospheric transformation mechanism and kinetics of AFRs initiated by center dot OH in the presence of O-2, taking triphenyl phosphate (TPhP) as a case. Results show that the pathway involving initial center dot OH addition to phenyl of TPhP to form TPhP-OH adduct, and subsequent reaction of the TPhP-OH adduct with O-2 to finally form phenol phosphate, is the most favorable for the titled reaction. The calculated overall reaction rate constant is 1.6 x 10(-12) cm(3) molecule(-1) s(-1), translating 7.6 days atmospheric lifetime of TPhP. This clarifies that gaseous TPhP has atmospheric persistence. In addition, it was found that ice surface, as a case of ubiquitous water in the atmosphere, has little effect on the kinetics of the rate-determining step in the center dot OH-initiated TPhP reaction. (C) 2016 Elsevier B.V. All rights reserved.