to show clearcut abnormality, It is noteworthy chat no thyroid abnormalities have been noted in children that received lesser exposure, i.e. the 6 children in the Ailingnac group, tne 54 chiidrea in the Utirik group and the 48 unexposed children in the sane age range. Only 4 cases of abnormalities have been noted in the aduits, 1 of these occurring in the lesser exposed group. ic should be noted that a low incidence of thyroid enlargement does appear in older people (greater than 50 years of age) of the Utirik and unexposed population (See Table III). The thyroids of 12 children and 2 adults have seen subjected to surgical exploration and the nodules removed. On surgical exposure, the thyroid gland was seen in most cases to be multinodular as shown in Fig. 2. Note the varied size of the nodules from several millimeters to several centimeters, some being cytstic, anc some hemorrhagic. microscopic diagnosis in all but one case was adenomatousgoiter. The Fig. 3 shows the microscopic appearance with the wide variation in size of — follicles closely resembling adenomatous goiter seen with iodine deficiency. Some pathologists claim to see radiation induced changes ia the thyroid glands but others do not. Fig. 4 shows the microscopic appearance of the mixed papillary and follicular carcinoma with localized metastases ina lymph node in a 41 year old woman. The nistologicai cxaminations of the thyzoids showed that in the children the tissues surrounding the aodules was usually abnormal while the thyroid tissue surrounding the nodular areas in the two acult cases was relatively normal. During the recent survey of the Marshallese peopfe in March 1969, it was found that 3 of the cases with accules wao had been exposed at less than 10 years of age had not shown satisfactory response to treeat- ment. In tact lL case showed a recurrence of a nodule that had previously disappeared in spite of the fact that this subject lad supposedly been on thyvoid treatment. swallowed. She complained of a lump in her throat whea she One new case of nodularity of the thyroid gland was found in a 34 year old woman, ‘These cases will be returned to Brookhaven National Laboratory in the near future for evaluation and possible surgery. CORRELATION OF THYROID FINDINGS WITH RETARDATION OF GROWTH AND DEVELOPMENT IN EXPOSED CHILDREN Based on anthropometric measurements and bone age radiographic studies it became apparent several years after exposure that some of the children, particularly boys who had been exposed at less than 12 years of age showed slight degrees of retardation of growth. This was particuiarl, marked in 2 boys who had been exposed at about 15 months of age wiio were considerably shorter in stature than brothers who were a year younger. 4] It has become increasingly clear that the retardation of growth noted in some of the children is associated with thyroid injury bringing about hypothyroidism. This was not detected in earlier years due to the fact