This study investigates the particle size distribution of eight polybrominated diphenyl
ethers (PBDEs) and five "novel" brominated flame retardants (NBFRs) in settled house
dust. Elevated surface dust (ESD) and floor dust (FD) were collected from 5 homes
in Birmingham, UK, yielding a total of 10 samples. Each sample was fractionated into
three different particle sizes: 125-250 μm (P1), 63-125 μm (P2) and 25-63 μm (P3).
Non-fractionated bulk dust samples (BD) were also analysed. BDE-209 predominated,
comprising an average 74.3%, 77.3%, 69.2%, and 62.7% ΣBFRs of BD, P1, P2 and P3 respectively.
Σ5NBFRs contributed 24.2%, 21.5%, 29.0% and 35.3% ΣBFRs, while Σ7tri-hepta-BDEs represented
1.5%, 1.2%, 1.7%, and 2.0% ΣBFRs. BEH-TEBP was the predominant NBFR contributing 76.9%,
75.1%, 83.1%, and 83.9% ΣNBFRs in BD, P1, P2 and P3 respectively; followed by DBDPE
which contributed 20.1%, 21.9%, 14.1% and 13.9% ΣNBFRs. EH-TBB, BTBPE and PBEB were
the least abundant NBFRs. Concentrations of Σ7tri-hepta-BDEs and BEH-TEBP in P3 exceeded
significantly (P < 0.05) those in P2, with those in P2 exceeding significantly those
in P1. In contrast, no significant differences were found between concentrations of
BDE-209, EH-TBB, BTBPE, and DBDPE in different particle size fractions. Concentrations
of Σ7tri-hepta-BDEs, BDE-209, and BEH-TEBP in ESD exceeded significantly those in
FD (P < 0.05). Normalising BFR concentrations to organic carbon content, did not alter
these findings. This suggests that differences in BFR concentrations between different
particle size fractions are caused by variations in particle surface area to volume
ratio, rather than by variations in organic carbon content.