Plutonium, Am, Cm and Sr in ducks maintained on radioactive leaching ponds in southeastern Idaho

Concentrations of 90Sr, 238Pu, 239,240Pu, 241Am, 242Cm and 244Cm were determined in tissues of mallard ducks (Anas platyrhynchos) maintained for 43-145 d on radioactive leaching ponds in southeastern Idaho. Highest concentrations of transuranics occurred in the gastrointestinal tract, followed closely by feathers. Approximately 75%, 18%, 6% and 1% of the total transuranic activity in tissues analyzed were associated with the bone, feathers, GI tract and liver, respectively. Concentrations in GI tracts were similar to concentrations in vegetation and insects in the littoral area of the ponds. The calculated total dose rate to the ducks from both 90Sr and the transuranic nuclides was 0.69 mGy d-1 (69 mrad d-1), of which 99% was to the bone. The potential effective dose equivalent to a human consuming the entire muscle and liver mass of one experimental duck with average nuclide concentrations was 0.46 microSv (0.046 mrem). Based upon average concentrations in experimental ducks and on surveys of wild waterfowl using this area, a conservative estimate of transuranic activity exported by wild ducks using the ponds during one year was 11.3 kBq (305 nCi). Similarly, the total amount of 90Sr exported in muscle, bone and lung of wild ducks in one year was 2.5 MBq (68.7 microCi).