ceived thyroid irradiation in 1954 seems to conform
in vw general way to the concepts outlined above.
Radiation appears to have been the cause of the
thyroid abnormalities seen, since 200 natives of the

same ethnic background and living under identical
conditions showed no thyroid disease. Furthermore,
there is no evidence that these people have been

exposed to other factors that might cause pathologie
changes in the gland: urinalyses indicate that the
iodine intake is adequate, and no dietary goitro-

venic factors have been implicated. In addition, the
dati in the present study show a much greater incidence of thyroid disease in children than in adults

in accord with the findings cited above. This greater

sensitivity of infants may also be related to the rel-

ative magnitudes of the dose of radiation received,

the infant ghind probably receiving five to ten times

the radiation dose that an average adult's) gland
received. Fhe dose range of from 700 to 1400 rads

delivered to the children’s thyroid glands is similar
to the doses received during thymic irradiation. The

apparently yreater incidence of pathologie chanves
in the glands of the Marshallese is not clear. It may

dose in these people is subject, as noted above, to

due to the radiation, but the mechanism has not

been known. With the recent development of frank
hypothyroidism in 2 of the most retarded boys in

the exposed group hypothyroidism: seems the most
likely cause. In 2 other retarded boys (

thyroid nodules have developed. However, it is’ in-

teresting that the exposed girls have shown verylittle
retardation of growth and development although the
nodules are more prevalent among them. Except for
the 2 boys with hypothyroidism. the rest of Ghe children with growth retardation have showin normal protein-bound iodine and cholesterol values. Minimal
“hypothyroidism may bave been missed and may be

enough to account forthe growth retardation seen. The

fincliny of high VTSIE levels in the 2 most retarded bows
with lwpothyroidisn and slight elevation in 2 other

retarded children strongly indicates primary hypothy-

roidism. The growth response of these children after
thyroid feeding will offer an interesting therapeutic.

test of the hypothyroid etiology of the growth retar-

dation,

j brits some

er study
est stuiclics wi

Surgery on ¢

RA Broadcle
fam). andl on
Mghey Clinic).

A Klinck (Ari
Rod 2, by Dr.

aren Nationa

Messner (New

mrough 6.

‘We are inde!

shock, CG. b.

SUMMARY AND CONCLUSIONS

in

Bhi, J. b. Je
ficking. for cor
indsav, Hi. A.

the thyroid gland were

found in a number of Marshallese people of Ronge-

the more heavily exposed population (55 living of

These people were exposed to varying doses of
external radiation to the thyroid) gland but not. to
internal exposure from radioiodine.
The growth retardation previously noted in some
of the exposed children has been assumed to be -

ared in) cir

Bewth rate in

;

explosions. The numbers are small, however, comalmost 15,000 individuals, as compared to 2 cases in
shehthy less than 5000 unexposed individuals.

were 31
Ate incredse '
mone (rect
fect of the |

\

dap Iskuxl who were accidentally exposed to racdio-

prising 19 causes ino a combined exposed group of

ech, 1166, si

7 yzecl. and

deliver 300 to [400 rads to the gland makes caution in

changes

X% Ackerman

active fallout in 1954. Definite thyroid nodules were
noted in Ll people, minimal changes in 5 others,

gher thyroid
gondence ane
assion tuid t]
priment of |

and hypothyroidism in 2. Al but 1 case occurred in

Marshallese sun

the original 64 persons), who received about 175
rads of whole-body giumma radiation, burns of the

skin from fallout products and internal absorption of
fission products. One case with a nodule was noted
inoun adult woman in the smaller Rongelap group
(16 of the IS are still alive) that had received less

than half the exposure of the other group. In 200
individuals of a control group not exposed no such
thyroid

abnormalities

were

found.

In

the

Pl, Cronkite, B,
exposedl 0
1955.
2 Conard, R. :
D7 people expos
JANA. 192:

y Sutow, WoO
of chitdren

more

heavily exposed ywroup, thyroid abnormalities developed in 55 per cent of children exposed at less
than ten vears of age. Five children were found at

Pediatics 36:
4 Harris, POU

.3. Cohn, 8. 1h,
~beings ane

surgery to have benign adenomatous goiters. The !

:7> sion, Some h
"On the Metrshe
fallout cud a

adult patient had a mixed papillary-and_ follicular
carcinomit, with localized metastasis. Two boys
showed marked retarcation of growth, apparently
owing to primary hypothyroidism.
The radiation etiolous in

these cases appears

+ by RP. Cro

ation, DC.

2 THD 535K.)
James, Ri, att
» Mochizuki, *

to

be reasonably certain in view of the following facts:
the thyroid ghinds received ao substantial dose of

radiation from radioiodines and external gamm
radiation (adults about 300 rads, and children about
700 to 1400 rads): and. the incidence of thyroid ail

normalities was high in the exposed group and ab-

sent in an unexposed control populagon living 0
the same ishund.
Do
.
The present. findings suggest that the seriousneess

of the internal hazard associated with fallout, parle
ularly from radioiodine. must be revised upwair®

PRIVACY ACT MATERIAL REMOVED

mtu

Ph resurvey +

thyroidisin, of thyroid adenomatoid lésions and of a
thyroid carcinoma after doses of radioiodine that

Pathologic

high ine

Nijdren.

and unpublished data by Godwin demonstrating a
reduced incidence of [-induced adenomas in rts
treated with thyroid hormone. This form of treat
ment, therefore, seems reasonable in the Marshal:
lese.
The implications of the present findings are two.
fold. In the first place, contrary to previous con.
cepts, the quantity of radioisotopes of jodine in
fallout of the close-in type associated with atomic.
bomb detonations must be regarded as a major long.
term hazard. Secondly, the development of hypo

the use ofraclioiodine necessary

No.

hallese

tiation

favorable effects of thfroid treatment. of
Patients
with nodules of the thyroid gland. The only expert,
mental evidence found directly applicable tg the
Marshallese situation is a paper by Nichols et alas

large uncertainties.
There appears to be an increased incidence of
thyroid carcinoma in inhabitants of Hiroshima and

Navasaki exposed to radiation from the atomic-bomb

te

The treatment of the exposed group with levothy.

roxine deserves some further comment, Bielschone,
skyand Astwood and Cassidy™ have reviewed the

be related to a greater dose of radiation received by

the MarshaHese since the calculations for thyroid

974+

June 23, bagg

PagteMotta tarde 6+ +

THE NEW ENGLAND JOURNAL OF MEDICINE

mona a

1398

PYAARRIEOPY

Man thyraie
19833.

8 Rall yo Ba
Modine level

i}

Press).
ae
% Axciracl, A... =

+ by Jow joshi | 2
ot ant, Cance
Ld

aa

Select target paragraph3