Applying the Multimedia Urban Model to measured PCBs, PAHs and PBDEs in urban areas

The Multi-media Urban Model (MUM-Fate) was applied to estimate: (1) emissions and fate of PCBs in Hamilton, Canada; (2) fate of PAHs in Hamilton, Canada; and, (3) the emissions and fate of PBDEs in Toronto, Canada. The model was evaluated for PCBs and PAHs using measured data that are presented as fugacity fractions. Net movement of PCBs from air to surface films, and subsequent removal by washoff to surface water was the significant urban pathway in the model. MUM-fate provides for SigmaPCB emissions from the city varying from 10 to 300 kg y-1. For four through six-ringed PAHs, rates of chemical reactivity in air and in surface film were shown to be sensitive MUM-fate parameters requiring further refinement. MUM-fate estimated Toronto's SigmaPBDEs emissions as between 100 and 422 g d -1, with most of those emissions lost through advection in air.