10
Dental Survey. Intra-oral examinations were
conducted as part of the physical examination.All
patients were examined with mouth mirror and
explorer. Illumination was by standard operating
light. Salivary pH was taken by use of pHydrion
Table 1
Age Distribution in Rongelap Adult Population, 1959,
Used in Aging Study
Exposed
Unexposed
Age, vr
M
F
M
F
20-24
0
3
1
6
30-34
35-39
3
1
2
4
3
4
5
4
1
0
on all subjects who were not eating candy or any
other foodstuff. Saliva samples were collected from
these patients at the time pH determinations were
made. Intra-oral radiograms were notavailable.
Dental examinations were carried out on thefollowing groups: 30 children at Majuro; all the
adults and children at Rongelap whowere in the
physical examination group; and a number of
children at Utirik.
Studies of Aging Criteria
Although the exposed group has shownno out-
wardevidence visible by gross observation of any
accelerated aging effect of radiation, it was
29-29
2
40-44
45-49
4
i
55-59
60-64
2
0
70-74
75-79
>> 80
]
0
2
50-54
65-69
0
1
12
2
0
6
2
3
Total
21
3
3
15
6
5
between the exposed and unexposed groups.
Therefore the data from the two groups have been
pooled with the objectives of presenting the meth-
odology, indicating the trend of changes with age
of the various agingcriteria chosen, and attempting
to determine a biological age score for individuals
anddifferent age groups.
This study was hampered by the small number
of people involved andthe lack ofvital statistics on
the Marshallese people. Another difficulty has
been the uncertainty of exact ages in somecases,
particularly in older people.
Data on aging criteria were recorded only on
adults 20 years of age and over. Of the 126 adults,
42 were in the originally exposed group and 84 in
the larger comparison population. Table 1 shows
the age andsex distribution. The ages were reasonably well distributed except for a smaller number
of older people (>>60 years of age).
The age criteria chosen were based on changes
generally believed to be associated with physiological senescence and represent only a small number
of the possible ones. They were selected witha
13
13
[1
l
6
3
5
\
3
7
14
2
1
1
0
0
2
0
0
0
3
1
5
0
2
3
thought desirable to have available measurable
criteria of possible age changes for use during normal physical examination. Therefore the over-all
objective of this study was to establish tests to
evaluate any possible radiation-induced senescence in the exposed group compared with the unexposed population living on the sameisland.
However, the data (presented in a later section on
results) collected during the 1959 survey (5 years
after exposure) showed no apparent differences
12
6
5
126
view toward ease of assessment during routine
physical examination underfield conditions, time
limitations, and languagebarrier. Therefore, unfortunately, tests of vigor and functional capacity
were necessarily limited.*
Of the 15 criteria selected, 9 were measured
directly and 6 were estimated on a 0 through 4+
scale. Five tests involved the integument: (1) skin
looseness, (2) skin elasticity (retraction time), (3)
senile changesin the skin, (4) greying of the hair,
and (5) baldness. Four tests involved the special
sense organs: (1) accommodation, (2) visual acuity,
(3) arcus senilis, and (4) hearing. The cardiovascular system wastested by (1) systolic and (2)
diastolic blood pressure recordings, (3) peripheral
arteriosclerosis, and (4) retinal arteriosclerosis.
There was one test of neuromuscular function.
Vigor was measured by hand strength measurements. The test methods are described below.
integument. A special skin caliper was designed for measuring skin looseness andelasticity
(Figure 8). The legs of the caliper can be opened
to any desired degree up to 5 cm onscale A by ad-
justing screw 8. Thespring tension whenthecali-
per is closed on a fold of skin results in a pressure
of about 500 g. The inner and outer surfaces of the
legs are calibrated in millimeter markings (C’).
*Several tests, such as pulse and blood pressure response to a
two-step test and vital capacity, were tried but not used because
they proved unsatisfactory.