The Availability of Environmental Radioactivity to Honey Bee Colonies at Los Alamos

Data are presented on the availability of tritium, cesium‐137, and plutonium to honey bee colonies foraging in the environment surrounding the Los Alamos Scientific Laboratory. Sources of these radionuclides in the laboratory environs include liquid and atmospheric effluents and buried solid waste. Honey bee colonies were placed in three canyon liquid waste disposal areas and were sampled frequently, along with honey, surface water, and surrounding vegetation, to qualitatively determine the availability of these radionuclides to bees ( Apis mellifera ) and to identify potential food chain sources of the elements. Tritium concentrations in bee and honey samples from the canyons increased rapidly from initial values of < 1 pCi/ml moisture to as much as 9.2 nCi/ml in 75 days after placement of the hives in the canyons. Seasonal patterns in foraging activities as influenced by weather and food availability were apparent in the data. It appears that several sources of tritium were utilized by the colonies, including surface water in the canyons and vegetation receiving tritium from atmospheric effluents and buried solid waste. Concentrations of cesium‐137 and plutonium were generally low or undetectable in bees throughout the study. However, levels of both nuclides increased by factors of 10–20 in bees from two of the canyon study areas during a 3‐month period in 1973. It was speculated that the liquid effluents in the two canyons were the source of the increased concentrations in bee samples, since this water was the only significant source of 137 Cs in the environs. The existence of at least three radionuclide sources in the Los Alamos Scientific Laboratory (LASL) environs complicates the interpretation of the data. However, it is apparent that honey bees can acquire 3 H, 137 Cs, and Pu from multiple sources in the environs.