title: Brominated flame retardants and the formation of dioxins and furans in fires and combustion.
abstract: The widespread use and increasing inventory of brominated flame retardants (BFRs) have caused considerable concern, as a result of BFRs emissions to the environment and of the formation of both polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) and mixed polybromochloro-dibenzo-p-dioxins and dibenzofurans (PBCDD/Fs or PXDD/Fs). Structural similarities between PBDD/Fs and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) suggest the existence of comparable formation pathways of both PBDD/Fs and PCDD/Fs, yet BFRs also act as specific precursors to form additional PBDD/Fs. Moreover, elementary bromine (Br2) seems to facilitate chlorination by bromination of organics, followed by Br/Cl-exchange based on displacement through the more reactive halogen. Overall, PBDD/Fs form through three possible pathways: precursor formation, de novo formation, and dispersion of parts containing BFRs as impurities and surviving a fire or other events. The present review summarises the formation mechanisms of both brominated (PBDD/Fs) and mixed dioxins (PXDD/Fs with X=Br or Cl) from BFRs, recaps available emissions data of PBDD/Fs and mixed PXDD/Fs from controlled waste incineration, uncontrolled combustion sources and accidental fires, and identifies and analyses the effects of several local factors of influence, affecting the formation of PBDD/Fs and mixed PXDD/Fs during BFRs combustion.
authors.affiliation: State key laboratory of clean energy utilisation, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, China.
authors.forename: Mengmei
authors.initials: M
authors.lastname: Zhang
authors.affiliation: State key laboratory of clean energy utilisation, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, China; Formerly with Chemical Engineering department, Vrije Universiteit Brussel, Brussels, Belgium.
authors.forename: Alfons
authors.initials: A
authors.lastname: Buekens
authors.affiliation: State key laboratory of clean energy utilisation, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, China. Electronic address: lixd@zju.edu.cn.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Li
keywords: Brominated dioxins (PBDD/Fs); Brominated flame retardants; Incineration; Mixed dioxins (PXDD/Fs); Uncontrolled combustion