Journal article
Monohydroxylated Polybrominated Diphenyl Ethers (OH-PBDEs) and Dihydroxylated Polybrominated Biphenyls (di-OH-PBBs): Novel Photoproducts of 2,6-Dibromophenol
Environmental science & technology, Vol.49(24), pp.14120-14128
12/15/2015
DOI: 10.1021/acs.est.5b03637
PMCID: PMC4717839
PMID: 26545041
Abstract
Hydroxylated polybromodiphenyl ethers (OH-PBDEs) are emerging aquatic pollutants, but their origins in the environment are not fully understood. There is evidence that OH-PBDEs are formed from bromophenols, but the underlying transformation processes remain unknown. Here we investigate if the photoformation of OH-PBDEs from 2,6-dibromophenol in aqueous solution involves 2,6-bromophenoxyl radicals. After UV irradiation of an aqueous 2,6-dibromophenol solution, HPLC-LTQ-Orbitrap MS and GC/MS analysis revealed the formation of a OH-PBDE and a dihydroxylated polybrominated biphenyl (di-OH-PBB). Both dimeric photoproducts were tentatively identified as 4′-OH-BDE73 and 4,4′-di-OH-PBB80. In addition, three debromination products (4-OH-BDE34, 4′-OH-BDE27, and 4,4′-di-OH-PBBs) were observed. Electron paramagnetic resonance spectroscopy revealed the presence of a 2,6-dibromophenoxyl radical with a six-line spectrum (a
H
(2 meta) = 3.45 G, a
H
(1 para) = 1.04 G, g = 2.0046) during irradiation of a 2,6-dibromophenol solution in water. The 2,6-dibromophenoxyl radical had a relatively long half-life (122 ± 5 μs) according to laser flash photolysis experiments. The
para-para
C-C and O-
para
-C couplings of these 2,6-dibromophenoxyl radicals are consistent with the observed formation of both dimeric OH-PBDE and di-OH-PBB photoproducts. These findings show that bromophenoxyl radical-mediated phototransformation of bromophenols is a source of OH-PBDEs and di-OH-PBBs in aqueous environments that requires further attention.
Details
- Title: Subtitle
- Monohydroxylated Polybrominated Diphenyl Ethers (OH-PBDEs) and Dihydroxylated Polybrominated Biphenyls (di-OH-PBBs): Novel Photoproducts of 2,6-Dibromophenol
- Creators
- Hongxia Zhao - Free Radical and Radiation Biology Program & ESR Facility, Carver College of Medicine, The University of Iowa, IA 52242, USAJingqiu Jiang - Free Radical and Radiation Biology Program & ESR Facility, Carver College of Medicine, The University of Iowa, IA 52242, USAYanli Wang - Free Radical and Radiation Biology Program & ESR Facility, Carver College of Medicine, The University of Iowa, IA 52242, USAHans-Joachim Lehmler - Free Radical and Radiation Biology Program & ESR Facility, Carver College of Medicine, The University of Iowa, IA 52242, USAGarry R Buettner - Free Radical and Radiation Biology Program & ESR Facility, Carver College of Medicine, The University of Iowa, IA 52242, USAXie Quan - Free Radical and Radiation Biology Program & ESR Facility, Carver College of Medicine, The University of Iowa, IA 52242, USAJingwen Chen - Free Radical and Radiation Biology Program & ESR Facility, Carver College of Medicine, The University of Iowa, IA 52242, USA
- Resource Type
- Journal article
- Publication Details
- Environmental science & technology, Vol.49(24), pp.14120-14128
- DOI
- 10.1021/acs.est.5b03637
- PMID
- 26545041
- PMCID
- PMC4717839
- NLM abbreviation
- Environ Sci Technol
- ISSN
- 0013-936X
- eISSN
- 1520-5851
- Grant note
- DOI: 10.13039/100000066, name: National Institute of Environmental Health Sciences, award: ES013661, ES017425, ES05605; DOI: 10.13039/501100002855, name: Ministry of Science and Technology of the People's Republic of China, award: 2013CB430403; DOI: 10.13039/100000054, name: National Cancer Institute, award: CA169046; DOI: 10.13039/501100001809, name: National Natural Science Foundation of China, award: 21207013, 21277017
- Language
- English
- Date published
- 12/15/2015
- Academic Unit
- Occupational and Environmental Health; Iowa Neuroscience Institute; Radiation Oncology; Iowa Superfund Research Program
- Record Identifier
- 9984001087002771
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