samples for radiochemical analysis. These studies
are not yet complete and have not been included
in this report.
The Navy kindly furnished a ship for the ex-
pedition, an LST, the USS Plumas County (Figure
3). The LST picked up medical equipmentfor the
survey, including a 21-ton steel room for carrying
out whole-body counts on the Rongelap people,
about the middle of February at Hawaii and
proceeded to Kwajalein. The medical team staged
in Hawaii and flew via military air transportation
to Kwajalein, boarded the LST, and proceeded to
Rongelap Atoll. At Rongelap the LST was beached
for easy accessibility to Rongelapvillage.
The 2!1-ton steel room, constructed at Brook-
haven National Laboratory for use in whole-body
gamma spectroscopy on the Marshallese in this
and future surveys, measured 5 ft 8 in. by 5 ft 8 in.
by 6 ft 6% in., with 4-in.-thick walls and ceiling
and a 2-in.-thick floor. The room had been set up
in the tank deck of the LST along with two 100channel analyzers, a 5-in. crystal, and otheraccessory electronics equipment. A dressing room
and showerfacility had also been constructed on
the tank deck for decontamination of personnel
prior to whole-body counts. (See Figures 4 and 5.)
The histories were taken, and the physical and
laboratory examinations were carried out at
Rongelapvillage in the dispensary, school building, and council house (see Figure 6). The examinations lasted 3 weeks.
Difficulties Associated with the Examinations
Several difficulties associated with carrying out
the examinations as well as interpreting the findings should be pointed out.
1) The language barrier made examinations
difficult since very little English is spoken by the
Marshallese.
However, there were sufficient
English-speaking Marshallese to assist the medical
team in most instances in carrying out the examinations.
2) The lack ofvital statistics or demographic
data on the Marshallese imposed a serious difficulty in interpretation and evaluation of the medi-
cal data. Records of births, deaths, etc., have been
madeby the health aides or magistratesofthe
villages and supposedly forwarded to the district
administrator; however, such records have been
poorly kept or lost in most instances and thus vital
statistics are practically nonexistent. Trust Territory officials are now attempting to assemble such
data.
3) It is unfortunate that many of the Marshallese, particularly in the older age group,are un-
certain oftheir exact ages, largely because few
written records of birth are maintained.
Comparison Populations
Duringthe first 2 years, two separate groups of
Marshallese people were used for comparison,
each of comparable size to the exposed Rongelap
group and matched in age and sex. However, this
population was found to be unstable, with a large
attrition rate over the 2 years, which made it un-
satisfactory. At the time of the 3-year survey, it
was found that during the preceding 12 months
the Rongelap population at Majuro Atoll had
doubled because of the influx of relatives who had
come back from otherislandsto live with them.
These people had been away from Rongelap
Atoll at the timeof the accidental exposure. This
group matched reasonably well for age and sex
and was of comparable size; moreover, since these
people were of the samestock genetically, they
provedto be uniquely appropriate to serve asa
comparison population. This group was therefore
used at the 3-year examination as a control and
again during the present survey.
PROCEDURES
History and Physical Examinations
Histories were taken by a Marshallese practitioner with particular emphasis on the interval
history during the past year.
Complete physical examinations were carried
out including examinations of the children for
growth and development, anthropometric measurements, and x-ray examinationsoftheleft wrist
and handfor bone developmentstudies; special
examinations of the skin with color photography
for selected lesions; ophthalmological studies includingslit-lamp observations, visual acuity, and
accommodation; and EGC and x-ray examina-
tions as deemed necessary.
Laboratory Examinations
Hematological examinations included three
complete blood analyses with WBC, differential,
platelet counts (phase microscopy), and hematocrit (microhematocrit method) done at about
weekly intervals.
The following examinations of the blood were
madeto determine genetically determined traits.