To evaluate risk via inhalation exposure of polybrominated diphenyl ethers (PBDEs) in office environment, thirty-six pairs air samples including PM.sub.2.5 (particles with aerodynamic diameter less than 2.5 mum), PM.sub.10 (particles with aerodynamic diameter less than 10 mum), total suspended particles (TSP) with matching gas phase were collected in office environment in Shanghai, China. The average concentrations of PM.sub.2.5, PM.sub.10 and TSP were 20.4, 27.2 and 50.3 mug/m.sub.3, respectively. Σ.sub.15 PBDEs mean concentrations in PM.sub.2.5, PM.sub.10, TSP and gas phase were 51.8, 110.7, 148 and 59.6 pg/m.sup.3, respectively. Much more PBDEs distributed in fine fractions than coarse ones. PBDEs congener profiles found in PM.sub.2.5, PM.sub.10 and TSP (dominated by BDE-209) were different from that in gas phase (dominated by the tri- to penta-BDEs). Approximately 3.20 pg/kg/d PM.sub.2.5 bound PBDEs can be inhaled into the lung; 3.62 pg/kg/d PM.sub.10 -PM.sub.2.5 (particles with aerodynamic diameter of 2.5-10 mum) bound PBDEs tended to be deposited in the upper part of respiratory system, and the intake of PBDEs via gas-phase was 2.74 pg/kg/d. The exposure of PBDEs was far below the minimal risk levels (MRLs), indicating lower risk from PBDEs via inhalation in the studied office in Shanghai.