Radionuclide Concentrations in Waterfowl Using a Liquid Radioactive Waste Disposal Area and the Potential Radiation Dose to Man

Abstract

Over 3 100 ducks, geese, swans and American coots (Fulica arnericana) were censused at the Test Reactor Area (TRA) radioactive leaching ponds on the Idaho National Engineering Laboratory (INEL) Site from January 1974 through March 1978. Twenty-six ducks and two American coots were collected from the TRA ponds from January 1974 through December 1977, and tissues were analyzed for y-emitting radionuclides. Duck tissues contained up to 29 radionuclides. Total average and maximum radionuclide concentrations were highest in gut followed by feathers. liver, muscle and skin. Chromium-51 had the highest relative radionuclide concentration identified (130,000 pCi/g-gut and 37,500 pCi/g-feathers). Cesium-137 was the predominant radionuclide in muscle with a maximum concentration of 4070 pCi/g. Edible duck tissues (muscle, liver and skin) had lower radionuclide concentrations than non-edible tissues (gut and feathers). The total amount of radioactivity being exported from the TRA environs during the 4-yr study period was estimated to be 5 x Ci. Cesium-137, 134Cs, and I3'I contributed 98% of the calculated potential radiation dose equivalent to man. The potential whole-body and thyroid dose commitment to man from consuming one waterfowl that was contaminated with the average radionuclide concentrations observed would be 12 and 7 mrem, respectively.

Radiation Doses to Waterfowl Using a Liquid Radioactive Waste Disposal Area

“…Solitary birds observed on consecutive days enabled estimation of residence times for 6 ducks and 1 American coot. Waterfowl were censused at the TRA ponds from February 1974 through May 1978, Monnuclide content by gamma spectrometry (Halford et al 1981 (1) where Di is the internal dose in rad (rad is the unit of absorbed dose) that waterfowl would receive from radioactivity in the body, 51.2 is a constant with units of (g-rad)(MeV" day-[Ci)-1, Q is the time integral of the concentration of radioactivity expressed in units of (gtCi" day)(g)-1, and E is the effective absorbed energy per disintegration with units of MeV.…”

“…Previous studies at radioactive waste disposal ponds on the Idaho National Engineering Laboratory (INEL) Site have shown elevated radiation exposure rates (Halford and Markham 1978) and the presence of radionuclides in wild waterfowl tissue samples (Halford et al 1981). The objective of our study was to determine the total combined radiation doses received by waterfowl from internal and external radiation sources at a liquid radioactive waste disposal area.…”

“…The use of nuclear waste disposal areas by birds and their consequent uptake of radioactive isotopes has been documented (Hanson and Kornberg 1956, Willard 1960, Brisbin et al 1974, Straney et al 1975, Domby et al 1977, Cadwell et al 1979, Craig et al 1979, Halford et al 1981. Although investigators have considered the potential radiation dose to man consuming waterfowl, no literature was found on radiation doses received from internal and external sources by birds frequenting a contaminated waste area.…”

“…Glass rod and thermoluminescent dosimeters have been attached to animals to measure radiation exposure or dose from external sources (French 1965, Turner 1975), but external contamination on the dosimeters can be a problem. Surgical implantation of dosimeters has been used in small mammals (Halford and Markham 1978) to eliminate the contamination problem; however, no similar studies have been done with birds.…”

“…The 94 species of birds using the TRA ponds during the study period included 22 species of ducks, geese, swans, and American coots (Fulica americana) (Halford and Millard 1978). Mallards and green-winged teal (A. crecca) were the most commonly observed waterfowl.…”