Marshallese) (138-141). These two individials exposed in utero described here
appear to be the first known cases developing thyroid nodules after radioiodine exposure.
4.
Problems Associated With the Thyroid Hormone Treatment Progr
In 1965 a BNL thyroid advisory panel recommended that the exposed
Rongelap people be placed on thyroid hormone treatment for life as a prophylac-—
tic measure to reduce the risk of further thyroid nodule development (by suppression of TSH levels) and possibly enhance growth and development in some ci
che children in whom this was retarded.* Since that time, the expeosel
Rongelap people have been receiving daily (or weekly) treatment with sya ~hetic
L-thyroxine (Synthroid, Flint Drug Co.). The Ailingnae people «:re also
placed on the hormone treatment regimen in 1969 because of the develoouent of
thyroid nodules in that group. In the exposed Utirik population and in the
unexposed groups, hormone treatment has been used only in those
who have had
thyroid surgery and, in some cases, to test the response of throid nodules to
a trial treatment with the hormone. The Synthroid doses used usually have
been 0.3 mg/day for people <50 years of age and 0.2 mg/dayz for tiose >50. However, the dosage has been adjusted downward in some clderly p_sple and in a
few people who showed symptoms on the dose given.
As pointed out in past reports, there have been proble.. of maintaining
a strict hormone treatment regimen in all of the people. Most of the people
take the medicatior faithfully, but a number of th2m have been careless in
maintaining the regularity of treatment in spite of .continued efforts by the
medical team and the resident physician ard his aides to imp 2ss upon them the
importance of the treatment program.
Onisrion of medicatior has been particu~
larly serious in patients who had undergone thyroid surgery. A number of
these have from time to time shown elevated serum TSH leve:3 and a few questionable signs of hypothyroidism. Fovtunately, xcept in one case (described
below), treatment was resumed before serious consequence. developed. In spite
of all efforts, some post-operztive patients still become _ax at times «about
regularity of medication, as ineicated by elevated serum TSH levels.
As discussed previous!y (see Sectior IX.A.), two Songelap boys exposed
at one year of age received iarger doses to the thyroid (perheps >2000 or more
rads) and developed hypothyroidism with stunted growth associated with atrophy
of the thyroid gland. One of these responded satisfactorily to treatment with
hormone,
showing enhanced growth and development and no clinical evidence of
hypothyroidism in spite of occasional elevations of serum TSH levels.
The
othe: case, however, though he had responded to the treatment with improved
growth status, has vecome a serious problem with regard to maintaining thyroid
_treatment. On a number of occasions, he has exhibited periods of apathy, development of vehavioral problems along with some degree of mental retardation,
and refusa! of food at times.
This was associated with high levels of TSH.
He has been hospitalized on several occasions with severe hypothyroidism.
above findings indicate the importance of maintaining a strict treatuent
The
*The rationale for such treatment has been supported by the finding that development of thyroid tumors in experimental animals is compietely prevented by
hypophysectomy (142).
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