16
and nutrition and are making satisfactory recovery from their radiation exposure.
Serious illness has occurred in two individuals but neither these illnesses nor clinical
findings in other individuals can be attributed toradiationeffects. One deathin May 1956,
that of a 46-year-old Rongelap man, was due to hypertensive heart disease. Previous
examinations had shown that the disease was undoubtedly present at the time of exposure to fallout radiation.
There is evidence of continued improvement of hemopoiesis. The mean lymphocyte count is slightly increased over the one-year levels, but is still slightly below the
mean control count, The mean platelet level is about the same as found at one year
after exposure and is still slightly below the control level, The mean neutrophile
count at one year after exposure had reached the control level. The delay in complete
recovery of lymphocytes and platelets is similar to that reported in the two-year
follow-up studies of the Japanese casualties of the atomic bombings (7, 8).
Evidence
from the Marshallese experience indicates that the lowered levels of these blood ele-
ments have not lowered the resistance of the people to disease, and the present levels
are not considered to represent a serious condition.
Residual changes in the skin from the beta irradiation continue to show improvement, Pigment aberrations are still evident in 15 cases and in four of these there is
also scarring with some adherence of the skin to the subcutaneous tissue. However,
there is no gross evidence of tissue breakdown or malignant change in any of these
lesions, and surgical repair is not considered necessary at this time. Histological examination of skin biopsies at sites of radiation lesions shows residual effects of radiation damage, but no evidence of premalignant or malignant changes.
Ophthalmological survey reveals that there are no radiation-induced lens opacities, and the incidence of ocular lesions is similar in exposed and control populations.
The radiochemical analysis of the urine of the Rongelap people shows measurable
activity which is largely due to cerium-144 - praseodymium-144 with only slight activity due to strontium-90, The body burden of these isotopes is estimated to be well below the permissible levels, Examination of bone specimens in the case of the one man
who died shows no radiation that can be definitely associated with fallout deposition in
the bones. Studies of radiographs of the femurs of the exposed children show no evidence of any bone defects from possible deposits of radionuclides.
Recommendations
Continued medical surveys of the Rongelap people on a yearly basis are recommended, particularly since certain blood elements have not completely recovered, and
continued observations of residual radiation effects on the skin are desirable.
The following studies are proposed for the next medical survey (three years postexposure). In view of the errors associated with single blood examinations and the
consequent difficulties of interpretation, it is desirable that several blood examinations be carried out over a period of several weeks on both Rongelap and control pop-
ulations, Routine history and physical examinations, growth and development studies
on the children, and special skin examinations with photography and biopsy of selected
lesions should be included. Baseline electrocardiographs should be carried out on all
people over 40 years of age and complete routine urine analysis should be carried out
on all personnel. In addition, radiochemical urine analysis should be repeated with
additional samples from unexposed people. It is also recommended that a geneticist
accompany the survey team to initiate baseline genetic studies.
Acknowledgments
The authors wish to express their appreciation to a number of individuals whose
efforts made possible the successful completion ofthis survey. Dr. Charles L. Dunham,