38
EFFECTS OF IONIZING RADIATION
and the severe, spotty epidermal injury with
minimal dermal injury are notable. The particulate nature and uneven distribution of the
fallout material was responsible for the spotty
nature of the lesions and, the large componen:
of soft energy beta radiation was responsible
for the greater epidermal injury. The prominence of pigmentary changes is probably re"lated to race.* It is generally conceded that
blondes with light pigment are more sensitive
to radiation than brunettes (17). Lastly it is
quite evident that sensitivity and response
varied with anatomic location.
In Table 3.3 are listed the approximate sur-
face skin doses required to produce recognizable
epidermal injury from beta radiations in ani-
in comparing animallesions from known do
with lesions in the exposed individuals in t
study in order to estimate the skin dose, sil
species differences in response may exist, 3
certain radiation factors are not well est
lished, sych as accurate knowledge of the b
spectrum of the fallout material and dose r:
Comparison with human data sutfers from w
differences in radiation energy and doses
ported und methods of determining the |
dose.
The low incidence of infection of the rad
tion burns is probably due to their superfic
nature. Ulceration and partial healing r
ceded the time of minimal granulocyte cout
It is conceivable, however, that with hig
Table 3.3.—Surface Doses Required to Produce Recognizeable Epidermal Injury
INVESTIGATOR
|
ANIMAL
|
:
1
Raper and Barnes (23) _._.. - |
Raper and Barnes (23)......|
Snider and Raper(24)... ._- |
Raper and Barnes (23).......
Rata.........
Mice........- i
Mige......-..,
Rabbits. __ ;
IsotorE
|
1
AVERAGE
ENRgROY
|
(Mav)
|
|
Henshaw,et al (22)... _..-- | Rate... |
P=
=
0.5
Lushbaugh (28)... -..-...- | Sheep... .... ;
Sf |
03
Moritz and Henriques (26)_.| Pigs.........|
Co
Moritz and Henriques (26)... Piga_._..__..
Moritz and Hennques (26). ‘| Pigs...___..-
Moritz and Henriques (26)__| Pigs._____..- '
Moritz and Henriques (26)... Pigs..._._... ,
Morita and Henriques (26). | Pigs...___.- |
|
mals. It is apparent from the table that beta
ray energy is of considerable importance in de-
termining the degree of injury.
According to
Moritz and Henriques, the difference in dose between that required to produce threshold skin
damage and that for permanent damage in pigs
is 500 to 1000 rep (26). One is not justified
* Reported clinical experience with radiation skin
lesions is based predominantly on the response of
white-skinned people, whereas the lesiona described
herein were observed primurily in the Marshallese,
a highly pigmented people.
P™
pe
P®
Pw
Se
'
|
©
|
0.05
©
0.01
'
|
O38
O5
Ca
|
oye
|
Sree
¥t
65
@s
OS
O65
|
1, 800-4, 000
4,000
2, 500
2, 500
5, 000
2, 500-5, 000
—
0.2
0.7
Scrrace Doag (xP)
20, 000-30, 000
4, 000-5, 000
2, 000-3, 000
|
!
1, 500-2, 000
L, 500-2, 000
1,500-2, 000
doses of whole-body radiation, the defen
against infection might have been sufficier
impuired to have resulted in serious compli
tions from skin lesions of the severity enco
tered.
Severe radiation injury is known to pre
pose to cuncer. The probability of the devel
ment of malignancies at the site of healed
sions is unknown. Certain factors appear
decrense the probubility: (a) The majority
the lesions were superticial.
(b) Visible si
of chronic radiation dermatitis are absent