The maximum permissible amount of alpha-emitting curium in the human body ranges from 0.01 to 1 millimicrogram. Inhalation presents the greatest occupational risk. Since curium has but recently become available in quantities approaching a gram, its metabolism is known almost solely by analogy with plutonium and closely related elements. An incident is described concerning a curium accelerator target aerosolized by explosion. Management of the spill, sampling, particle sizing, and medical findings are presented. Seven of the 27 persons present showed low levels of curium excretion. The data from this incident were compared with those from three other inhalation exposures to curium compounds at this Laboratory.