Pollution profiles and risk assessment of PBDEs and phenolic brominated flame retardants in water environments within a typical electronic waste dismantling region

The aim of this study was to assess the pollution profiles of various typical brominated flame retardants in water and surface sediment near a typical electronic waste dismantling region in southern China. We found that polybrominated diphenyl ethers (PBDEs), 2,4,6-tribromophenol (TBP), pentabromophenol (PeBP), tetrabromobisphenol A (TBBPA), and bisphenol A (BPA) were ubiquitous in the water and sediment samples collected in the study region. In water, Σ₁₉PBDEs (sum of all 20 PBDE congeners studied except BDE-209, which was below the detection limit) levels ranged from 0.31 to 8.9 × 10² ng L⁻¹. TBP, PeBP, TBBPA, and BPA concentrations in the water samples ranged from not being detectable (nd—under the detection limit) to 3.2 × 10² (TBP), from nd to 37 (PeBP), from nd to 9.2 × 10² (TBBPA) and from nd–8.6 × 10² ng L⁻¹ (BPA). In sediment, Σ₁₉PBDEs ranged from nd to 5.6 × 10³ ng g⁻¹, while BDE-209 was the predominant congener, with a range of nd to 3.5 × 10³ ng g⁻¹. Tri- to hepta-BDE concentrations were significantly (p < 0.01) correlated with each other, except for BDE-71 and BDE-183, and octa- to nona-BDEs concentrations were significantly (p < 0.05) correlated with each other, except for BDE-208. BDE-209 was not significantly correlated with tri- to nona-BDEs. Risk assessments indicated that the water and sediment across the sampling sites posed no estrogenic risk. However, different eco-toxicity risk degrees at three trophic levels did exist at most sampling sites.