eerad 30 types.°7 For the three major pathogens found, the overall infection rates were: Entamoeba histolytica, 18.2%; hookworm, 5.5%; and Trichuris trichwra, 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 may be related to chronic fungus and other infections, particularly of the skin. Complementfixation studies for parainfluenza1, 2, and3, respiratory syncitial, psittacosis, and Qfever showed antibodiesto all groups of viruses except that for Asian influenza, which probably had not yet seriously involved the people of the Marshall Islands. The antibodytiters appeared to be somewhatlowerin the exposed people. Immunoelectrophoretic analysis showed neither a paraproteinemia nora typical picture of antibedydeficiency syndrome, but a high frequencyof increases of someof the immunoglobulins was noted. Blood volume studies with 51Cr-labeled sodium chromate showeda significant reduction in red cell mass and/or plasma volume. However, there is some indication that Americansliving in the Islands for more than 1 year mayalso haveslightly lowered values. Tritiated water has been used to establish the relationship of blood volumeto lean body mass. Acknowledgments The cooperation of many agencies and persons was necessary to carry out these surveys successfully. The authors are deeply grateful for valuable assistance to many individuals too numerous to name. Weare particularly grateful to the people of Rongelap and Utirik Atolls for their cooperation in these examinations. Manyofficials of the Atomic Energy Commission, particularly Dr. John R. Totter and Dr. H.D. Bruner and their staff of the Division of Biology and Medicine, and Mr. W.A. Bonnet and Mr. W.Streenan of the Honolulu Operations Office, were most helpful in coordination of arrangements and in supporting the surveys in every way possible. Weare gratefulto the officials of the Department of the Interior, particularly Mrs. Ruth Van Cleeve and Mrs. Elizabeth Farrington, and the 9006301 officials of the Trust Territory of the Pacific Islands, including High Commissioners Mr. E.E. Johnston and Mr. W.R. Norwood; the Director of Medical Services, Dr. W.M. Peck; the District Administrator for the Marshall Islands, Mr. Robert Law; the Director of the Majuro Hospital, Dr. John laman, and members ofhis staff; the Trust Territory Representative at Kwajalein, Mr. W.M. Ownby, and Dr. Ezra Riklon at the Ebeye Hospital; all were most helpful. The Pacific Missile Range Facility at Kwajalein was of great assistance in furnishing necessary airlifts and materials. Mr. Frank Granich andothers of Global Associates at Kwajalein, Dr. Y¥.C. Smith at the Kwajalein Hospital, and Colonel D.B. Milar, Commanding Officer, were extremely helpful. At Brookhaven National Laboratory, contributions were made by manyindividuals in many departments, including Medical, Instrumentation and Health Physics, Photography and Graphic Arts, the Shipping Section, and others. We are grateful to the following people at BNL for their support and advice: Dr. Maurice Goldhaber, Director; Dr. V.P. Bond, Associate Director; Dr. J.B.H. Kuper, Chairman of the Instrumentation and Health Physics Department; Dr. E.P. Cronkite, Chairman of the Medical Department, and others in his Department, including Drs. D.D. Van Slyke, J.S. Robertson, and S. Cohn, and Messrs. A. Finn, G. Jackson, and W. J. Walsh. We appreciate the assistancein statistical analyses given by Mr. Keith-Thompson. In regard to advice and consultation on the thyroid pathology in the Marshallese, we are indebted to Drs. S. Warren and W.A. Meissner of the New England Deaconess Hospital; Dr. B.P. Colcock, Lahey Clinic; and Drs. L.K. Dahl, H.L. Atkins, and H.A. Johnson of Brookhaven National Laboratory. We are particularly grateful to the nursing staff here for their kindness and excellent ° care given the Marshallese thyroid cases. Wewishalso to thank Mrs. J. Redzinak for her devotedsecretarial assistance, and Mrs. M. Dienes for her editorial help. References 1. Cronnire, E.P. er av., The Effects of Ionizing Radiatwn on Human Beings: A Report on the Marshallese and Amencans Accidentally Exposed to Radiation Fallout and a Dtscussion ofRadiation Injury in the Human Being, AEC-TID 9358, U.S. GovernmentPrinting Office, Washington, D.C., 1956.