ings quacured in air from the planar fission
product Geld. Frem tie preceding paragraph
it in conn that on additionn! 50 to 100 r of laberatery radiation on an average of 75 r, prob
ably would have resulted in some mortality.
Correcting this average value for geometry,”
it fellows that the minime! lethal dose for man
showed casentially identical degrees of depres
sion. The lympheryte counts of Groups | snd
I] were constantly depressed at « level of ap
prosimatety 2000 celle, Then, while sensitive ot
very lew doses, this endpomt may be a poor
index of the degrees of exposure at higher doses.
T
expensed in a fasion product field is approximately 225 r measured in air.
3
wrt
the high sublethal range (20), and the estimated rate of decrease of platelet level with increasing dore in this dosage range. Such an
soi
d
:
2
|
+
Oa ee
anermanas va
Fiat ac 49—Camealetire arutrephiic counts for (ireape
I (Rongetag) and if ( \ilinginac) and central (ireap
A at thedjaof marimam depression.
|
wo}
——
Te
sor
hoa
§
.
ool
T
‘
“yT
S
- + —4y_"
a
/
a?
we
oH
_@
ee
A
ads
:
'
-
T
/
—~
|;
|
+
a!
T
gp pe
ror
ol
T
SEAR
PAE Pee
7m
cytes and platelets can be seen in Tables 4.2 to
4.5 and Figures 4.9 to4.12. Lymphocyte counts
were depressed appreciably even in the lowexposure Group FV. In the higher dose groupa,
however, with widely different physical estimates of exposure the lymphocyte counts
|
eS i
tor
446 Periphersi Counts os an ladex of Severity
The relative value ofetheseveral lematological determinations in estimating the degree of
exposure, as well as the approximate dose
ranges over which maximum sensitivity for
each determination exists, can be extimated by
comparing the degree of hematological change
ainongy the several exposure groups. The relative degree of change in neutrophiles, lympho-
!
|
sof
analysis leads to the same conclusions as those
derived from neutrophile data.
of Exposuce
;
be
a
~_-
+
:
we
an
vo
in
aa
.
|
in
‘
.
2setDpNBEBEN OM OR
“
SBHEHKH ONAN
‘
|
BS
LYMPNOCYTES 5 0°
*From gemetric and depth das considerations set
forte in Mection £. 1 roentgen mensured in air jo a
Pictee 4.10 —-Comuletire lymphocyte counts for
Groupe | i Rongelap)s end Ii i Vilinginee) and controd Ciroap Uiat the time of marioum deprvanoan,
in its effect on man to approtimatety 1.5 reentgers of
penetrating x- or genuine radiation under geometric
conditions usually used for large animals in the lah
The total neutrophile count of Ciroup Fo was
fasion produrt fleld would be expectedl to be equivalent
oratory.
Thus, the minimal lethal dose for man ex-
Jumed fo pepetrating radiation under the usual laboratory conditions woukd be approvimately 335 r.
The
degree to which energy differences between the two
radiations inay alter thin ratho of effects cannot be
evaluated at present.
consistently more depressed than was that of
(sroup IT and the difference was of the order of
MM) to 1000 cells. However, day to day wide
fluctuations in the neutrophile counts occurred.
Accordingly, this endpoint appeared to be of
bnuted usefulness ax an index of relative expo-
ee
It is possible also to estimate the added increment of dose that would have resulted in
seme mortality among the Group I people from
consideration of the minimum platelet counts
observed, the platelet levels in dogs exposed in