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). -~ 75 -