13 variation in the concentration factor for plutonium in fish muscle and bone tissues for species from different trophic levels or global locations. Rockfish from the area near the Farallon Islands collected in 1977 contained 2394240, associated with the muscle and bone at concentrations of 0.008+0.003 and 0.043 + 0.004 pCi/kg wet weight respectively (No 78c). The average concentration in the upper 100 m of seawater was 0.7 + 0.3 fCi/1l (No 78c). Using the concentration factors from the Marshall Island results and the average Farallon water concentration, the predicted Plutonium in the muscle and bone would have been 0.010 + 0.004 and 0.10 + 0.04 pCi/kg. These concentrations are in reasonable agreement with the measured values. From the total weights of the tissues and concentrations of 23942405, listed in Table 2 and the assumptions developed above, it is possible to reconstruct concentrations in any assemblv of tissues and organs to compare with the 1972 concentration data. Table 3 summarizes measured plutonium concentrations in Kwajalein Atoll reef fish from 1972 (Ne 73, Sc 75) and concentrations in the whole, eviscerated, and viscera samples collected in 1975 and 1976. The concentration of 2392405, in the 1972 dry eviscerated reef fish from Kwajalein Atoll range from 4 to 960 pCi/kg. Our measurements show concentrations in eviscerated reef fish 22 to 5000 times lower than these values. The concentration in dry eviscerated snapper is 440 times lower than the concentration measured in the 1972 snapper. Concentrations in 1972 dried viscera samples ranged from 9-430 pCi/kg. Our reconstructed viscera concentrations are orders of magnitude less than this range of Vio DOE ARCIT