By use of standard models and theories, the number of cancer fatalities caused by dispersal of plutonium is estimated. This process includes development of estimates of Pu toxicity for inhalation and ingestion, calculation of meteorological dispersal using the Gaussian plume model, estimates of resuspension effects from empirical models, and estimation of very long term effects from a comparison with natural uranium in soil. The conclusions on Pu toxicity are that we may expect one cancer for each 200 μg of reactor-Pu (2.5 g/Ci) inhaled or for each 1.0 g ingested. For dispersal in a city, we may expect about one eventual fatality per 18 g of reactor-Pu dispersed; this effect is dominated by inhalation from the initial cloud, with early resuspension effects somewhat less important and long-term effects essentially negligible.