and handfor bone development studies); studies of aging criteria: special examinations of the skin with color photographyof selected lesions: ophthalmological studies including slit-lamp observations, visual acuity, and accommodation, audiometric examinations; cardiovascular survey, and X-ray examinations as deemed necessary. In 1959, 96 exposed people, including their children, and 166 unexposed people were exam- ined on Rongelap. Cardiovascular Survey. In view of the possible association oflate effects of radiation with cardiovascular disease, the following cardiovascular survey wascarried out. L. Clinical histories recorded present and past health and illnesses, espectally cadiac and pulmonary symptoms. 2. Physical examinations included the usual observations in the cardiovascular system in regard to the rhythm and rate of the heart; the nature of the heart sounds and murmurs, tf present; the size and shape of the heart by clinical indications; changes in the arterial walls as observed by inspection of the retinal arteries and by palpationofthe radial, brachial, and dorsalis pedis arteries; and the ap- pearance of the veins. 3. Instrumental procedures: Systalte and diastole blood pressures were obtained with the cuff-type aeronoid sphygmomanometer. Oscillometry readings were obtained from both legs at calf level by the Collins type of oscillometer. The highest of the readings obtained at different pressure levels was used as a single reading for each subject. Electrocardiograms were taken on people 20 years of age and over (84 unexposed and 38 exposed individuals). The electrocardiograms were taken by a Sanborn Direct Writing apparatus which had been specially shock mounted for field use.* In almost all subjects the electrocardiograms were taken with 12 leads, to include three standard bi- polar limb leads, three augmented unipolar limb leads, and six unipolar or V chest leads in accord with the standard 12-lead procedure recommended by the American Heart Association. The technical quality of the electrocardiogram was in most instances relatively good, but there were two handicaps. The electric power for the instruments was obtained from a generator on the LST by running a cable ashore to outlets in the various build“We are most grateful ta the Medical Equipment Research Department, US. Army, Fort Totten, N_Y.. for use of this instrument on a permanent loan basis. ings used for the medical examinations. Inductior currents often caused interference, and groundin of the instruments at times was difficult. Ther: were also technical variations because of variabl: line voltage and amperage. X-rayfilms of the ches: were taken on sclected subjects when indicated The number taken was kept to a minimum t avoid additional radiationof the exposed people. even though the dose involved was extremels small. The films were used chiefly for the study ol the lungs and, to some extent, for measurement | heart size and shapc. Chest films were obtained on; 11 subjects in the unexposed group and 7 in the exposed group. it should be pointed out that there was no standardized basal or adjusted level of physical activity, such as resting for one hour before takinz the tests. The patients were seen in the course of the usual examination, as might occur in the outpatient department of a hospital. Arthritis Survey. During the course of other studies on the Rongelap population, it was possible to obtain information on the prevalenceol arthritis and allied phenomena. Since little is knownof the prevalence of these diseases in tropical populations, any such data would be a contribution to the “geographic pathology” of the arthritides’ besides being of interest in connection with the possible adverse influence of radiation exposure on degenerative diseases. X-rays of the hands and wrists were graded for osteoarthritis on a scale of 14+ to 4+ by the method of Kellgren and Laurence" as modified by Blumberg et al." The same x-rays were used to detect any cases of rheumatoid arthritis, other arthrittdes, or bony abnormalities.* A small aliquot of serum(0.3 to 0.5 ml) was used to determine the presence of “rheumatoid factor” by the bentonite flocculation test of Bozicevich et al." In this test, a titer of 42 or greater is considered post- tive, ‘Ac doubtful, and any titer below “es nega- tive.* A joint examination on each of the Rongelapese was performed by the medical examiners. and any individual with significant joint findings was re-examined by oneof the physicians experienced in the diagnosis ofjoint disease. Treatment of the joint disease was undertaken where indicated, *We are indebted to the following personnel of the National Institutes of Health: Drs. R.1. Black, J.J. Bunim, and E.G; 1. Bywaters for reviewing the x-rays: and Dr. K. Bloch for performing the bentonite Ancculation test.