Nitrogen and phosphorus modelled in freshwater eutrophication: The director’s cut

Most Life Cycle Impact Assessment (LCIA) methods to date estimate freshwater eutrophication impacts from phosphorus (P) only. There is a need to account for the contribution of N to freshwater eutrophication as well. We developed Fate Factors (FFs) for both dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphorus (DIP), distinguishing emissions from soil and emissions to freshwater. Preliminary emission-weighted global average FFs are (in days) FF_soil_DIN = 117; FF_river_DIN =251; FF_soil_DIP = 21; FF_river_DIP = 241. The fate model is consistent with recent advances in marine eutrophication impacts assessment and complements such an approach.