Occurrence of a Broad Range of Legacy and Emerging Flame Retardants in Indoor Environments in Norway

TLDR

The study investigates the occurrence of 37 organohalogen and organophosphate flame retardants in Norwegian households and primary school classrooms. The authors sampled air and dust from 48 homes and 6 classrooms and assessed exposure sources and pathways in households. About 80 % of the targeted FRs were detected in air and dust, with decabromodiphenyl ether and tris(2-butoxyethyl) phosphate showing the highest dust concentrations, 2,2′,4,4′‑tetrabromodiphenyl ether and tris(1‑chloro‑2‑propyl) phosphate dominating air, the emerging FR TBECH/DBE‑DBCH exhibiting the highest indoor air levels reported, strong dust‑air correlations (R 0.36–0.76) indicating dust can estimate air concentrations, and frequent vacuum cleaning reducing dust FRs while dermal contact was as important as ingestion for organophosphate FR intake.

Abstract

This study investigates the occurrence of 37 organohalogen and organophosphate flame retardants (FRs) from Norwegian households (n = 48) and classrooms from two primary schools (n = 6). Around 80% of the targeted FRs were detected in air and dust from the sampling sites. The comparison of settled dust with floor dust revealed no statistical differences between median concentrations of the FRs (n = 12). Decabromodiphenyl ether and tris(2-butoxyethyl) phosphate showed the highest median floor dust concentrations in both environments. In the air samples, the highest concentrations were observed for 2,2′,4,4′-tetrabromodiphenyl ether and tris(1-chloro-2-propyl) phosphate. Remarkably, the emerging FR, 4-(1,2-dibromoethyl)-1,2-dibromocyclohexane, abbreviated as TBECH or DBE-DBCH, showed the highest indoor air concentrations reported in the literature (households, 77.9 pg/m3 and schools, 46.6 pg/m3). Good Spearman correlations between the FR concentrations in dust and air (0.36 < R < 0.76) showed that is possible to estimate the concentrations in air from analyzed dust, or vice versa. Sources and pathways of exposure to FRs were assessed for the households. The main findings were that frequent vacuum cleaning resulted in lower FR concentrations in dust and that dermal contact with dust, for both children and mothers, was as important for the intake of organophosphate FRs as dust ingestion.