14 low excretors either heterozygous or homozygous for the dominantallele. Striking differences in the incidence of high excretors in various populations have been demonstrated, and it appears thatthis genetic polymorphism may be of considerable value in anthropo-genetic investigations.”*'”” As a part of the study of the genetic relationships andoriginsof various Pacific peoples, this report extends observations on BAIB excretion to the Micronesians inhabiting the Marshall Islands. The fact that some of the Micronesians were ex- carried out every year need be done only once tion exposure can, temporarily at least, increase of their cargo ships (Figure 9), which routinely madethe roundsofthe islands for gathering copra, for carrying out the survey at Rongelap. Accordingly, for the 1960 survey the team consisted posed to considerable radiation in 1954 is of special interest here, since it is known that radiaBAIB excretion,”* and studies on the Marshallese population mayelucidate possible long-term ef- fects. Urine samples from 65 exposed and 119 unexposed people (75.7% of the population ofthevillage) were collected in plastic bottles containing thymolpreservative. The sexes were equally repre- sented, and the ages varied from 3 to >/0 years. In some cases several members of the same family were included, and some kinships suitable for genetic analysis were available. Eighteen samples collected on Utirik were also studied. Urines were kept at 4°C and shippedin refrigerated containers to Seattle for analysis. These studies were carried out by one of us (B.S. Blumberg) and Dr. S.A. Gartler of the Department of Medicine, School of Medicine, University of Washington. Studies were completed 2 to 3 weeksafter collection of the specimens. Determinations of BAIB were carried out by high voltage electrophoresis on paper,” and creatinine was determinedbythe alkaline picrate method. Radionuclide Body Burden Evaluation The methods used in the radionuclide body burden evaluation are described later in a sepa- rate section. 1960 Survey BACKGROUND MATERIAL The 1960 survey was reducedin size and scope and limited to a very brief examination ofthe exposed people only. Several factors brought about this change. The people had recovered to the extent that certain special examinationspreviously every two to three years. In addition, as pointed out before, the Trust Territory officials were concerned aboutthe slowness of economic recovery of the Rongelapese and felt that the numerousvisiting scientific teams, particularly those with large ships and crews, were partly responsible for the unrest of the people and therefore requested that the size of the surveys be kept to a minimum. It was decided to defer the gammaspectrographic analysis until 1961. The Trust Territory officials agreed to greater participation of their medical personnelin future surveys and to the use of one of only one physician and one technician from Brookhaven National Laboratory, and the re- mainder of the medical group, arranged bythe Trust Territory, included its Director of Public Health, two Marshallese medical officers, and two Micronesian laboratory technicians. The Director of Dental Services and oneof his dental officers also accompaniedthe team to carry out treatment of the people. The District Administrator of the Marshall Islands accompanied the team in order to consult with the people on their agricultural program.* As in the previous year, several of the exposed people nowliving at Kwajalein and Majuro Atolls were examined atthese atolls prior to the Rongelap visit. PROCEDURES As in previous surveys, ¢xaminations were carried out in the dispensary and the schoolhouse in Rongelapvillage. Interval medical histones and complete physical examinations were carried out *Again in 1960, when the team arrived at Rongelap, the magistrate requested a meeting with the people. Theline of questions and discussion was about the same as that reported for the previous year. Resistance toward the examinations was expressed by only one or two of the people. Objections were again raised against the ban on eating coconut crabs, which selectively concentrate Sr*° to such an extent that their consumption had to be prohibited (Figure 4). The people were assured that these crabs were being repeatedly examined and that, whenit was safe to eat them, immediate notification would be given. Fish poisoning apparently had been jess of a problem during the past year since only one case had been noted, and the subject was not brought up again. Following this meeting, cooperation by the people in the examinations was almost complete.