Application of a congener‐specific debromination model to study photodebromination, anaerobic microbial debromination, and FE0 reduction of polybrominated diphenyl ethers
Open Access
- 8 January 2010
- journal article
- research article
- Published by Wiley in Environmental Toxicology and Chemistry
- Vol. 29 (4), 770-778
- https://doi.org/10.1002/etc.119
Abstract
A model was used to predict the photodebromination of the BDE‐203, 197, 196, and 153, the major components of the octa‐polybrominated diphenyl ether (PBDE) technical mixture, as well as BDE‐47, and the predicted results were compared to the experimental results. The predicted reaction time profiles of the photodebromination products correlate well with the experimental results. In addition, the slope of the linear regression between the measured product concentrations of the first step of the photodebromination products and their enthalpies of formation was found to be close to their theoretical value. The photodebromination results of the octa‐BDE technical mixture were compared with anaerobic microbial debromination results and were found to be the same in both experiments. The debromination pathways of technical octa‐BDE mixture were identified and BDE‐154, 99, 47, and 31 were found to be the most abundant hexa‐, penta‐, tetra‐, and tri‐BDE debromination products, respectively. In addition to photodebromination and anaerobic biodebromination, the model prediction was also compared to the zero‐valent iron reduction of BDE‐209, 100, and 47 and the same debromination products were observed. Good correlation was observed between the photodebromination rate constants of fifteen PBDE congeners and their calculated lowest unoccupied molecular orbital (LUMO) energies, indicating that PBDE photodebromination is caused by electron transfer. Furthermore, the rate constants for the three different PBDE debromination processes are controlled by C–Br bond dissociation energy. With the model from the present study, the major debromination products for any PBDE congener released into the environment can be predicted. Environ. Toxicol. Chem. 2010;29:770–778. © 2010 SETACThis publication has 20 references indexed in Scilit:
- Development and validation of a congener‐specific photodegradation model for polybrominated diphenyl ethersEnvironmental Toxicology and Chemistry, 2008
- The Dehalococcoides Population in Sediment-Free Mixed Cultures Metabolically Dechlorinates the Commercial Polychlorinated Biphenyl Mixture Aroclor 1260Applied and Environmental Microbiology, 2007
- Natural sunlight and sun simulator photolysis studies of tetra- to hexa-brominated diphenyl ethers in water using solid-phase microextractionJournal of Chromatography A, 2006
- Microbial Reductive Debromination of Polybrominated Diphenyl Ethers (PBDEs)Environmental Science & Technology, 2006
- Anaerobic degradation of brominated flame retardants in sewage sludgeChemosphere, 2006
- Theoretical Calculation of Thermodynamic Properties of Polybrominated Diphenyl EthersJournal of Chemical & Engineering Data, 2005
- Quantitative Analysis of 39 Polybrominated Diphenyl Ethers by Isotope Dilution GC/Low-Resolution MSAnalytical Chemistry, 2005
- Anaerobic microbial and photochemical degradation of 4,4′-dibromodiphenyl etherWater Research, 2002
- Polybrominated diphenyl ethers: occurrence, dietary exposure, and toxicology.Environmental Health Perspectives, 2001
- Kinetics of Halogenated Organic Compound Degradation by Iron MetalEnvironmental Science & Technology, 1996