RADIOACTIVITY IN THE BIOTA AT ISLANDS OP THE CENTRAL PACIFIC, 1954 ~- 1958 Evaluations of the radioactive contamination of biological organisms in the vicinity of the Eniwetok Test Site have been made by the Laboratory of Radiation Biology since Operation Crossroads in 1946. In order to determine the geographical limits of the contamination, the area of the surveys was extended,in 1954,to include several islands away from the test site. in Pigure 1, The "off-site" collecting areas, include locations in the Marshall, shown Caroline, and Gilbert Islands and were selected because of their direction and distance from Eniwetok as well as their accessibility. Surveys made at these islands in 1954, 1955, 1956, and 1958 showed that in 1956 and 1958 the radioactivity decreased with distance and direction from the test site and that at the islands within a 130-mile radius the radioactivity was approximately tenor more times that of the other islands. Tarawa, atoll 800 miles to the southeast of the test site, contained very low levels of radioactivity. an DOE ARCHIVES The results of studies by several laboratories on the radioactive contamination of areas adjacent to the test site and in the open ocean in 1954 to 1956 have been summarized by