a Table 14 Serum Iodine Serum Protein-Bound Iodine Date Group 1959 1962 1963 Rongelap Rongelap Rongelap 1964 1964 Medical team Rangelap 1965. 1965 1966 1966 Rongelap exposed Rongelap unexposed Rongelap exposed Uurik exposed 1959 Rongelap , Average. ug% Range. ug% No. samples Percent over 8 ug% 6.2 8.6 8.1 4.1- 9.2 4.6~ 12.0 1.9- 12.0 12 14 29 16 64 66 7.6 7.0 6.1 11.8 4.1-11.9 3.9 - 10.7 3.1- 11.8 6.9 - 28.7 31 19 9 25 42 28 16 92 49 71 2.5- 6.9 2.0 - 10.2 10 1! 36 Serum Butanol-Extractable Iodine 4.9 2.7- 8.7 12 Serum Iodine Chromatography Group Total iodine, Av ng% 1954-1964 1965-1966 Rongelap Rongelap 6.98 7.40 1964-1966 Americans 1966 Curik 18.10* 5.09 lodoprotein, Av ug% =9—-7,4+7;, Av pe% No. samples 2.22 2.80 4.53 4.21 19 18 0.80 3.76 25 9.20 4.00 5 *One Uurik sample wasquite high in total iodine (32.0 n.e%) suggesting contamination of this sample. The remain- ing 4 samples showedtotal iodine levels very nearly equal to the combined iodoprotein and thyroxine values. iodine plustriiodothyronine iodinein these sera was 4.53 ug%. Five plasma samples from Utirik people assayed in 1966 showed an unusually high average of 9.2 ug% of iodoprotein. (See Table 14.) These data may be compared with results obtained on 25 normal North Americancontrols residing temporarily in Washington, D.C., who showed an average serum iodoprotein level of 0.8 ug% and an average T,+ 7, iodine level of 3.76 pg. Dietary lodine and Urinary Excretion of lodine. The supplyof iodine in the Marshallese diet has generally been considered adequate in view of the 5008310 cal Laboratory in 1965 gave an average value of| 105 ug iodine per day (range: 19.5 to 279), which is within the range of values found in an unselected population living in the Eastern United States.** A complete table of urinary iodine excretion data is presented in Appendix 4. Thyroid Uptake of Radioiodine. Uptake of radioiodine by the thyroid was tested in 1965 on 21 Marshallese (12 exposed and 9 comparison adults) with no known thyroid abnormalities. Studies with ‘**I were performed with a collimated |-in. Nal crystal 25 cm from the patient’s neck. The '**I was milked daily from tellurium132 bound to a resin by elution with 0.1 Af NH,OH, andit was calibrated against a '**Cs standard. The '**I (5 to 10 pCi) was administered by mouth before breakfast, and counts were obtained over the neck at =, 1, 2, 3, and 4 hr; a single 3-hr urine was assayed for '**I. A predose count of the neck was performed, since a small amount of what was presumed to be ‘*'Csin- _— — The average value for the amount of thyroxine large consumption of seafood. Analysis of 24-hr urine samples from 28 people at the Boston Medi- en eed tion in PBI is a general phenomenon whichaffects the entire population. The difference between PBI and BEI in 12 cases was 1.5 pg%, which is somewhat greater than an average value of 0.6 ug% in the United States.*'-** This was suggestive evidence for the presence of iodoprotein in serum, and the results obtained by column chromatography substantiate this, as an average iodoprotein level of 2.22 ug% was found.