The determination of polybrominated diphenyl ether congeners by gas chromatography inductively coupled plasma mass spectrometry

Abstract

Polybrominated diphenyl ethers (PBDE) are flame retardant chemicals used in everyday household items such as computer casings and household textiles. Leaching and migration of these chemicals from products has been reported as the cause for the widespread presence of these compounds in our environment. While PBDEs are predominantly analyzed by GC-NCI-MS, GC-HRMS or GC-ECD, this paper investigates the potential of GC-ICP-MS for the determination of PBDEs. The application of this methodology for the analysis of PBDEs in NIST SRM 2977 Mussel Tissue and NIST 1941b Marine Sediment is also presented. The extreme sensitivity of inductively coupled plasma mass spectrometry (ICP-MS) for atomic information makes GC-ICP-MS a promising alternative for analyzing PBDEs at low concentrations or in small sample sizes. In this work, the instrumental detection limits of a GC-NCI-MS were directly compared to those of a GC-ICP-MS for a mixture of 28 PBDE congeners including the decabrominated PBDE-209 congener. The GC-ICP-MS instrumental method demonstrated superior sensitivity over the GC-NCI-MS for all of the PBDE congeners with absolute detection limits ranging from 0.2 pg to 0.3 pg as compared to 1.5 pg to 24.3 pg for GC-NCI-MS. The GC-ICP-MS method was then used to quantify PBDE congeners in Standard Reference Material (SRM) 1941b Organics in Marine Sediment and SRM 2977 Freeze-Dried Mussel Tissue (Organic Contaminants and Trace Elements). The mass fraction of PBDE congeners in these SRMs determined by GC-ICP-MS were within 13% (8.5%) and 7% (2.5%) (mean difference (1 SD)) of previously determined values for SRMs 1941b and 2977, respectively. The PBDE 209 value in SRM 1941b determined by GC-ICP-MS compared favorably to the consensus value from a recent interlaboratory comparison using this material (28.7 ng g⁻¹ ± 2.9 ng g⁻¹versus 24.4 ng g⁻¹ ± 14.1 ng g⁻¹).