56 status of the people in relation to that of the unexposed comparison population, particularly in regard to any possible late developingeffects of their exposure, their hematological status, and theinfluence ofthe slightly contaminated environment on the assimilation, excretion, and body burdenof radionuclides. Meatcal histories of the intervals between the ex- A cardiovascular survey of the adults showed no outstanding differences between the exposed and unexposed groups. The people appeared to have less hypertension on the whole than is noted in people in the continental United States. Anarthritis survey showed no greatdifferences be- tween the exposed and the unexposed people, and rate of the exposed group over the past 6 years seemsto indicate no noticeable effect of their exposure on fertility. The 24 births represent a rate of 48 per 1000 population, compared with 37.3 for about the sameincidenceas is seen in American populations. Anophthalmological survey showed no remarkable differences between the exposed and unexposed groups exceptpossibly a slightly greater number of cases of pterygii, pingueculae, and cornealscars in the exposed group. It is not know whetherthis finding is of any significance in relation to their radiation exposure.Slit-lamp observations showed no opacities of the lens characteristic of radiation exposure. As a whole, visual and accomodation levels in the Marshallese appeared to be above the average in the U.S. population. A dental survey showed nosignificant differences in either caries rate or incidence of peridontal disease between exposed and unexposed groups. The poor oral hygiene generally observed in the Mar- 3-year period for the comparison population rep- rate in teen-age children, severe peridontallesions aminations in 1959 and 1960 were, for the most part, uneventful and revealed no major epidemics of disease. Several deaths had occurred and new births were reported. In the exposed group, two deaths occurred and in the unexposed group, three. Two of the latter were due to influenza acquired during an epidemic on Kwajalein. The four deaths that have occurred in the ex- posed people since exposure represent a mortality rate of 8.1 per 1000 population, compared with 8.3 for the comparison population and 6.8 for the Marshall Islands as a whole. A review ofthe dirth the Marshall Islands (1957). The 20 births over a resent a rate of 62 per 1000 population. A somewhat greater incidence of miscarriages and stillbirths has been noted in the exposed women, but be- cause of the paucity of vital statistics in the Marshallese and the small numberof people involved, the data are not readily amenable to statistical shallese had its usual results, namely, high cares in adults (heavy calculus and loss of alveolar bone), and eclentulous mouthsin the aged. Radia- tion exposure did not appearto haveaffected developing dentition in the exposed children. analysis. Late effects of radiation. Various parameters usualls associated with aging were measured or estimated ona Qto++ scale (skin looseness, elasticity. and directly related to radiation effects. The incidence hearing; cardiovascular changes including blood pressure and degrees of peripheral and retinal Physical examinations showed the exposed and the unexposed people to be generally in a state of good health. No diseases were noted that could be of various disorders in both adults and children was about the samein the exposed and unexposed groups. In connection with growth and developmentstudies, a project on theverification of accuracy of ages of the children has not been completed and,therefore, the suggestive evidence previously presented of possible lag in statural growth in the exposed children must await confirmation. It was noted, however, that in the 6-year chronological age group, three boys and onegirl out offive boys and two girls in the exposed group exhibited significantly retarded skeletal maturation as judged by x-ray examination. The birth dates of these children seemedto be fairly well established. senile changes; greying of the hair and balding, accomodation, visual acuity, and arcus senilss. arteriosclerosis; neuromuscular function: and hand strength). Comparison of these measurements in exposed and unexposed individuals of the same age groups showed no apparentdifferences. A biological age score was calculated for indiviuals and groupsbyuse of an average percentagescore. Life shortening effects of radiation have not been apparent. As noted, the mortality rate was about the same in the exposed as in the unexposed people. The one case of cancer that developed in the exposed group occurred at 5 years after exposure, too soon,it is believed, to bear any particular relation to radiation exposure. Leukemia surveys including physical findings, studies of white cell