Pollution status, phase partitioning, potential sources, and health impacts of polybrominated diphenyl ethers in Hangzhou offices

Polybrominated diphenyl ethers (PBDEs) have persistence and toxicities, so exposure to PBDEs is associated with various health hazards. Thus, it is crucial to study the pollution status of PBDEs in office microenvironments, which are the primary active places for people working in offices. We collected 80 samples (air, particulate matter, and dust) from 10 offices in Hangzhou and detected the congeners of PBDEs using GC-ECD. Median concentrations of total PBDEs in particle phase, gas phase, and dust were 108.28 pg/m³, 35.63 pg/m³ and 59.22 ng/g, respectively. BDE-209 was the primary congener in various media. The particle size distribution was bimodal and was primarily distributed in the ＜1.1 and > 7 μm particle size segment. We predicted the concentration of PBDEs in different phases to better explore the fate of released PBDEs. The measured value of the equilibrium coefficient between gas and dust indicated that PDBEs in the gas-phase were transferred into the dust. The predicted $C_{g-pre}$ value of PBDEs was smaller than the measured value $C_g$, especially BDE-209. The measured concentration of low-brominated PBDEs in particles was higher than the predicted concentration, which may be because the non-equilibrium model did not consider the dry and wet deposition of particles. The PBDE concentrations in the materials were in the following order: mouse pad < cable shell < plastic folder < eco-board. The analysis of indoor sources of PBDEs demonstrated that plastic folders, eco-boards, and mouse pads and cable shells may be potential sources of PBDEs in the air, dust, and particles, respectively. The HQ of PBDEs in Hangzhou offices was far less than 1, indicating that the health risk was within the acceptable range.