HEMATOLGeTe

at doses well belowthe lethin range. and ineren--

ing dose resuit< mn one or donna

farther ae.

crease in count
Lavmphocvte sepresston ay
pears to have no caused reloonsthip wath aense
radiation deaths.
¢) Platelet counts iave veer -tudied most

extensively in dogs (26)
Y wath neutroplhiles,
the rapidity and maguitude of depression = 4

function of dose below the letha: ringe
Viax
mum depression oceurs by fe Sth or both chis
with doses in the high letha. cenge. by che loth
to 15th day at subletual level). Recovery begins during the 3d week. bur is not complete fv
the 380th day when most stu es live been term:
nated. Insufficient dita us available to ond
cate the time required

for

1

the mouse using spleri fomogenates, induced
bacterial infections ard spoutaneous Infectious

have indicated that curgea

neutrophile levels

is correlated with

the absolute neutrophile count following whore

body irradiation (15)

59

“oo, and essentiilly the same calculated exposste bar for which control hematological

as were considerably different (the Lympho\te

count ts pot sutable for comparison since

degree

of dlepression was essentially the same

Po vouese ereups and the higher-dose Rongelap
ETO p

At the time of penk depression for

euc! orferment. the neutrophile counts were
esse iialiy identient in terms of absolute counts,

boat

ooisnmlerably different in terms of the re-

4a

Approximation of Minimal Lethal Dose for
Man

sper ove eoutrol values
Thus, some evidence
oi forded that) ipsolute counts. rather than
eurt> relative to control values, may be the
wer sehaole index of exposure in this dose

omplete recover,

Considerable evidence ua. cluding studies

exist. below which sueviva

BSEP AA LIONS

From data an dogs.

t

appears that surviva, is linels uiiess meutr
phile counts remain below Pvc cells for 4

period of time.

Platelet data on devs neaeate that animals
with external purpuri nat. pdatelet counts of

soe

oncheation of severity of exposure can

be viene freni a comparison of minimum inav dat, counts in fapanese groups in which fataltes occurred
In general, a significant

hoinber

dv

ft deaths was encountered only in in-

dandy

nin

vhose neutroplule count fell below

dn) Group 1. #2 or approximately 50 per-

cent cad neutrophile counts below 2000 at some

us

tating the observation period, and 10
weroens had counts below 1000, By this ert
terror thea. the etfective dose received by the

platelet counts asa fuietion at dose rn the sa:
lethal range. The response if te olatelet cout

du
epproxiuately an additional 60 to 100 r
cee ceriuired to lower the nentrophile count by

50,000 or below

Sufficient data oon

arge on minus ure not

vet available te quanafs tie extent rf as
mum depression of © ther “he nentrophile or
in the present study aa. or uch less subject

fluctuation than were tae

eurronhile or lyr

phocyte counts

preceeding

For

' e

o

rerser s,

systematic investigaten «ot che platelet oud
leukocyte counts in ticee a mats toa funericn
of dose in the subleth orate are imdicated
It Is not possible t+ sas it present whether
severity of exposure, or of radiation diame
correlates better with ubsol te levels ef pernpit
eral blood count. or

from

control

woth

dearee

or pre-expesuse

of ethane

evel

Sore

evidence on thes pout con pe aa ned by cara

paring the degree of depre stor ef the mente
phile counts 1 Crror ps |
nel PTE enh
of

Korvelap oeoole iupproached the lethal range.
Poche cdoe

hoes

aim

Cronkite and Bond, unpublished

in the high sublethal close range.

broese ditt enn oe applied to man, an addi-

met

© tf Liter would have placed the dose

veo
tte Jethal range. On the other hane.
powecer or is eclenr from the presence data and

Sores

ontealy xperence with therapeutic ridia-

or om eatropatle counts between P00: and
Phe
Gaan betes are in genernl well tolerLoe
fhumat bemgs with these levels of nenGed

tes

show

one chiniea,

evidence of

ness,

ve cateady actives and generally doe not need
eon tietie Gafrprotie therapy,
Por peo de of Crronp Pare estimated to have
soe

Ter ois

thenheted from: dose rate read-

Select target paragraph3