Radionuclides and trace elements in fish collected upstream and downstreamof Los Alamos National Laboratory and the doses to humans from the consumption of muscle and bone

The purpose of this study was to determine radionuclide and trace element c oncentrations in bottom-feeding fish (catftsh, carp, and suckers) collected from the confluences of some of the major canyons that cross Los Alamos Na tional Laboratory (LANL) lands with the Rio Grande (RG) and the potential r adiological doses from the ingestion of these fish. Samples of muscle and b one (and viscera in some cases) were analyzed for H-3 Sr-90,Cs-137, U-tot, Pu-238, Pu-239,Pu-240, and Am-241 and Ag, As, Ba, Be, Cr, Cd, Cu, Hg, Ni, P b, Sb, Se, and Tl. Most radionuclides, with the exception of Sr-90, in the muscle plus bone portions of fish collected from LANL canyons/RG were not s ignificantly (p<0.05) higher from fish collected upstream (San Ildefonso/ba ckground) of LANL. Strontium-90 in fish muscle plus bone tissue significant ly (p<0.05) increases in concentration starting from Los Alamos Canyon, the most upstream confluence (fish contained 3.4E-02 pCi g(-1) [126E-02 Bq kg( -1)]), to Frijoles Canyon, the most downstream confluence (fish contained 1 4E-02 pCi g(-1) [518B-02 Bq kg(-1)]). The differences in Sr-90 concentratio ns in fish collected downstream and upstream (background) of LANL, however, were very small. Based on the average concentrations (+/-2SD) of radionucl ides in fish tissue from the four LANL confluences, the committed effective dose equivalent from the ingestion of 46 Ib (21 kg) (maximum ingestion rat e per person per year) of fish muscle plus bone, after the subtraction of b ackground, was 0.1 +/- 0.1 mrem y(-1) (1.0 +/- 1.0 mu Sv y(-1)), and was fa r below the International Commission on Radiological Protection (all pathwa y) permissible dose limit of 100 mrem y(-1) (1000 mu Sv y(-1)). Of the trac e elements that were found above the limits of detection (Ba, Cu, and Hg) i n fish muscle collected from the confluences of canyons that cross LANL and the RG, none were in significantly higher (p<0.05) concentrations than in muscle of fish collected from background locations.