HEMATOLOGIC OBSERVATIONS
sure severity except when counts on groupsto be
compared are performed at the same time.
The platelet count showed a more systematic
trend than did the neutrophile count. Differences between the low-dose Group IV and
controls at the time of maximum depression for
all groups with the exception of adult males
ES[CONTROL GROUP ATES
POP
ook—
,
t
90r “repsmor
;
ze
mt i ae I
= sob
ae | + [°
o
5
—
9 8 ( a 25 22 3 37 4 15 a9 8S BT 69
PLATELETS 110°
6888 8838 8 8
CUMULATIVE PER CENT
TIME OF PEAK DEPRESSION OST EXPOSURE Oa|i8S
ane ba 2shebe
os
{
|
9
St
Conclusions
1. Conswrration Or Tne clegree of depression of peripheral cellular elements indicates
that exposure of Group I was inoderately
severe, probably within 50 to 100 r of the level
where some fatalities would have resulted.
2. The degree of effect evidenced in Group I
people is not inconsistent with the physical
estimates of gamma dose received, when the
geometry of exposure and other factors are
considered.
FIGURE 4.11.—Cumulative platelet counts for Groups
I (Rongetap), ( CAilinginae), and IV (Utinik) and
control Group A at the time of maximum depression,
°
4.5
tH
aap ws ow
PLATELETS x 10°
Figtre 4.12.—Cumulatice platelet counta for Group I
CRonyelap)y at the time of masrimuim depression and
G montha after erposure,
could be noted, and detectable differences existed
between the menns for the Marshallese higher
exposure groups. Platelet counting is us easy
as, and more reproducible than lenkocyte counts
1.21). Thus, the platelet count may prove to
be a useful index of degree of exposure throughouta large part of the sublethal range.
The above considerations are in accord with
previous findings on human beings and animals.
61
Beta lesions of the skin, and the
low levels of internal radioactive contamination observed are considered not to have contributed significantly to the hematological
changes seen.
3. The extensive serinl hematological data
obtained, considered in connection with previous data, allow reasonably accurate characterization of the hematological response of human
beings exposed to single doses of penetrating
radiation in the high sublethal range. The
pattern of change of some elements may be
different for higher dose levels; (see exrlier
discussion).
The time course of events is different from
that observed in large animals and may be described as follows:
a) The total white count increases during
the first 2 or more days andthen decreases below
normal levels. The total count then fluctuates
over the next 5 or 6 weeks, with no definite
Ininimum and with some values above normal
(the presence of thermal or beta lesions, or
other actite processes during this time may account in part for these fluctuations). The
count becomes stabilized during the 7th or sth
weeks at low levels, and minimum counts prob-
ably oceur at this time. A definite trend upward is apparent in the 9th or 10th weeks:
however complete recovery may require several
nonths or more,
b) The neutrophile count parallels the total
white bload cell count, Complete return to
normal values does not occur for several months