STUDY ON THE SIMULTANEOUS DETERMINATION OF POLYBROMINATED DIPHENYL ETHERS AND SOME ALTERNATIVE BROMINATED FLAME RETARDANTS BY GAS CHROMATOGRAPHY - MASS SPECTROMETRY METHOD (GC-MS)
Abstract
Studies on the characterization of detailed profiles of brominated flame retardants (BFRs), including both legacy and alternative compounds, are still limited in Vietnam. In this study, concentrations of 41 polybrominated diphenyl ethers (PBDEs), hexabromobiphenyl (BB-153), pentabromoethylbenzene (PBEB), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), and decabromodiphenyl ethane (DBDPE), were determined using a gas chromatography - mass spectrometry (GC-MS) method with electron capture negative ionization and selected ion monitoring mode (ECNI-SIM). Several fluorine-labeled compounds (FBDEs) were used as surrogates and internal standards, showing their ability to replace expensive isotope-labeled compounds (13C12-PBDEs). A specific capillary column with relatively short length (15 m) and thinner stationary phase (0.10 μm) was used to prevent thermal degradation of BFRs, especially high-brominated compounds such as decabromodiphenyl ether (BDE-209) and DBDPE. Good chromatographic separation was achieved for most BFRs and labeled compounds. The quantification method showed high accuracy, linearity (R2 > 0.99), and sensitivity (detection limits from 0.13 to 5.0 ng/mL). Concentrations of the target compounds and recoveries of the surrogates were calculated using relative response factors with the internal standard/isotope dilution approach. The validated GC-MS method was successfully applied to analyze BFR concentrations in some settled dust samples collected from northern Vietnam. The total BFR levels ranged from 78 to 57,000 ng/g, with the most predominant compounds as BDE-209 (36–34,000 ng/g) and DBDPE (33–17,000 ng/g). These results indicated the co-occurrence of legacy BFRs (i.e., PBDEs) and their replacement formulations in the environment, suggesting the need for comprehensive monitoring of multiple BFR classes in Vietnam.
