turn of the people to Rongelap. The bodylevels of the unexposed people who returned to the island also increased, becoming indistinguishable from those of the originally exposed group. However, the levels remain well below the maximum permissible limits. Analyses of bone samples on one of the men who died showed3.7 strontium-90 units/g calcium. OTHER STUDIES . Other studies have been carried out on the Rongelap people which are notdirectly related to radiation effects. An intensive intestinal parasite survey showed that the people were infected with many types of protozoa and helminths. This finding did not entirely accountfor the generally high incidence of eosinophilia. Otherfindings that need further explanation are the general anemic tendencies, the high plasma protein levels with increased gamma globulin, and the higher than normal!levels of serum protein-bound iodine and vitamin B,,. Another investigation ts concerned with genetic studies and determination of the anthropological background of the-Marshallese from genetically determined traits. Among the traits studied were blood groups and hemoglobin and haptoglobin types. The results shed somelight on the origin of these people and the homogeniety of the population. Their blood groups resemble most closely those of the people from Southeast Asia and Indonesia, and the population appears to be relatively homogeneous. DIFFICULTIES ASSOCIATED WITH THE EXAMINATIONS As mentioned in previous reports, several difhculties were associated with carrying out the examinations as well as interpreting the findings. 1. The language barrier made examinations difficult, since verylittle English is spoken bythe Marshallese. However, there were sufficient Eng- lish-speaking Marshallese to assist the medical team in most instances. 2. The lack of vital statistics or demographic data on the Marshallese imposed a serious diffi- culty in interpretation and evaluation of the medical data. Records of births, deaths, etc., have been made bythe health aides or magistrates ofthe vil- lages and supposedly forwarded to the district administrator; however, such records have been in- complete or lost in most instances, and vital statis- tics are therefore inadequate. Trust Territory officials are nowattempting to assemble such data. 3. There is uncertainty on the part of some of the Marshallese as to their exact ages, particularly among the older group. This imposes certain diff-, culties in interpreting someofthe studies to be outlined. DOE ARCHIVES COMPARISON POPULATIONS During the first 2 years, two separate groups of Marshallese people were used for comparison, each of comparable size to the exposed Rongelap group and matchedfor age and sex. However,this population was foundto be unstable, with a large attrition rate over the 2 years, which madeit unsatisfactory. At the time of the 3-year survey,it was found that during the preceding 12 months the Rongelap population at Majuro Atoll had doubled becauseofthe influx of relatives who had come backfrom otherislandsto live with them. These people had been away from Rongelap Atoll at the time of the accidental exposure. This group matched reasonably well for age and sex and was of comparable size. Since the return of the people to Rongelap, however, this group has about doubled in size. Since the people are of the same stock genetically, they are uniquely appropriate to serve as a comparison population and have, therefore, been used since 1957. ° 1959 Survey BACKGROUND MATERIAL Organization For the 1959 survey, 5 years after the accident, the medical team consisted of seven physicians, one dentist, two scientific specialists, and nine technicians from various institutions and laboratories in the United States. Several Marshallese practitioners and interpreters assisted in carrying out the examinations. A group offive scientists from the University of Washington, headed by Dr. E.E. Held, accompanied the group to collect soil, marine, and plant samples for radiochemical] analvsis. These studies are not includedin this report. Prior to the main survey on Rongelap,several members of the team visited Majuro to examine [0 ee wee ae er See ae