CHAPTER 1 INTRODUCTION 1.1 OBJECTIVES Project 4.1 was organized with the following specific objectives: (1) To evaluate the severity of the radiation injury in the human beings exposed to the fallout radiation. (2) To provide for all necessary medical care for these individuals. (3) To conduct a scientific study of radiation injury in human beings. 1.2 GENERAL DESCRIPTION OFTHE EXPOSEDGROUPS Shot 1 of Operation CASTLE was detonated on 1 March 1954. Following the detonation significant amounts of radioactive materials fell on the following populated neighboring atolls: (1) Ronyelap, (2) Ailinginae, (3) Rongerik, and (4) Utirik. Exposure groups are identified accarding to their geographical location at the time of exposure. The numbers of individuals involved, their location, the distance of the atoll on which they were located from the site of the detonation on Bikini, the calculated dose of radiation, the probable time of beginning of the fallout and its duration are tabulated in Table 1.1. The Rongelap group received the highest calculated dose. These individuals were living under relatively primitive conditions in lightly constructed palm houses (Fig. 1.1). The Ailinginae people were a part of the Rongelap group who were on their Ailinginae farms from the time the fallout began to the time of evacuation. Their calculated dose was smaller than that of the other members of their group that had remained on Rongelap. The third and largest group of Marshallese, inhabitants of the atoll of Utirik, received the smallest dose of radiation. The American military personnel exposed on Rongerik were aware of the sipnificance of fallout and promptly put on additional clothing to protect the skin. As far as duties would permit, they remained inside of Butler-type buildings. In contrast, most of the native Marshallese remained out of doors and thus were more heavily contaminated by the material falling on the atolls. Some of the Marshallese, however, went swimming during the fallow! and many of the children waded in the water; thus washing a considerable amount of the material from their skins. 1.3 EVACUATION AND EARLY CAREOF THE EXPOSED GROUPS The American military personnel were evacuated to Kwajalein via air in two groups on 2 March. The native Marshallese were evacuated by a combination of air and surface trans- 15 +. so ee one Miges a es oe . wo. oes 7 ee ee eae