showedthe increase in proteins was largely due to an increase in the gammaglobulin fraction. The reasonfor this is not apparent. Numerous chronic infections may be an explanation. Sodium levels in the urine and food indicated about the same consumption of NaCl as in Ameri- cans. The generally lower incidence of hypertension in the Marshallese might be related to the fact that the former native diet was probably lower in salt content than the present, more westernized diet. It will be interesting to see whether the incidence of hypertension will later increase. Serum cholesterol levels (1957, 1959) were somewhatlowerin the exposed population than in the comparison or Utirik populations, but were in the low normal range. No abnormally low readings were noted. Serum creatinine levels (1957) were in the normal range with no abnormallevels noted. Serum vitamin B,, concentrations (1958, 1959) Immunoelectrophoretic analysis showed neither a paraproteinemia nora typical picture of antibodydeficiency-syndrome, but a high frequency ofin- creases of some of the immunoglobulins was noted. Blood volume studies with Cr®'-labeled sodium chromate showed significant reduction in red cell mass and/or plasma volume in 15 of 23 Marshallese. DIFFICULTIES ASSOCIATED WITH THE EXAMINATIONS As mentionedin previousreports, several difficulties were associated with carrying out the examinations as well as interpreting the findings. 1. The language barrier made examinationsdifficult, since very little English is spoken by the Marshallese. However, there were sufficient English-speaking Marshallese to assist the medical team in most instances. were generally significantly higher than American levels. The possibility of contamination of the samples with bacteria producing vitamin B,, must be considered, since myeloproliferative andliverdiseases were not seen. 2. The lack of vital statistics or demographic data on the Marshallese imposed a serious difficulty in interpretation and evaluation of the medi- were generally slightly elevated. Evidence for thyroid dysfunction was not apparentin the people. Glucosurta and elevated blood sugar were found in 8 people (1 exposed and 7 unexposed). An increased incidence of diabetes is prevalent in the Mar- ministrator; however, such records have beenin- Serum protein bound iodine levels (1957, 1959, 1962) shallese people. A survey for intestinal parasites (1958) showed 735% of the people to be infected with various types.'’ For the three major pathogens found, the over-all infection rates were, for Entamoeba histolytica, 18.2%; for hookworm, 5.5%; and for Trichuris trichiura, 34.3%. Eosinophilia >>5% has consistently been noted in about half the people. The fact that half the cases with eosinophilia showed no helminthic infections at all suggests that other factors besides parasitic infections must be responsible. The eosinophilia maybe related to chronic fungus and otherinfections, particularly of the skin. Complementfixation studies for parainfluenza1, 2, and 3, respiratory syncitial, psittacosis, and Q fever showed antibodies to all groups of viruses except that for Asian influenza, which probably had not yet seriously involved the people of the Marshall Islands. The antibody titers appeared to be somewhat lower in the exposed people. 90007490 cal data. Records of births, deaths, etc., have been madebythe health aides or magistratesofthevillages and supposedly forwardedto the district ad- complete or lost in most instances, and vital statistics are therefore inadequate. Trust Territory officials are now attempting to assemble such data. 3. There is uncertainty on the part of some of the Marshalleseas to their exact ages, particularly amongtheolder group. This imposes certain difhculties in interpreting some of the studies to be outlined. COMPARISON POPULATIONS Duringthefirst 2 years, two separate groups of Marshallese people were used for comparison, each of comparable size to the exposed Rongelap group and matched for age and sex. However,this population was foundto be unstable, with a largé attrition rate over the 2 years, which madeit un- satisfactory. 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 because of the influx of relatives who had come back from 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