Ree wee Oe OE “Why redal benieoeas U.S. normal peep we ae 4 No besives (Clink) Wuosal 3 ath tug. ol Figure 41, Percentages of peopl: in various groups having givenlevels of thyroylalaalia (by READ, 173. and a highincidence of parasitic infections, A preliminary examination of North Americans with abnonnal leukocyte counts, hawever, did not show a correlation between leukocytosis and jodoprotein level. Further studies on this are indicated, "Phe chemical nature of this iodopratein is also une known. By analogy with findings in various thy: roid discases,"* the iodaprotcis is likely ¢o be come priscd inaindy of jodoallbumin arising from the iodination of scrum protcins, It is now recognized, however, that thyroglobulin (PG) is a minor component of normal plasma, Ata reported concentration of 3,120.49 (S.EAL) ng/ml (range <1.6 to 20.7) in normal North Aniericans,! and assuming an iodine content of 0.5/4, this would be equivalent te an iodoprotcin iodine bevel of 2.60.25 ng/dl, Atthough it seems unlikely, a preore, Uhat circulating Uhnvroglobulia in the Marshallese could be clevated enough to give were ee ws an todoproteny level of 3 to 4 pad (iw. > 300 pg whe 24 hie bagead Bai TSlt Ble Jtbe Figure 42. Effect of TSHL adininisteation on thyroglobulin levels, 1975. 0, Persons with thyroid lesions (Rongelap plus Ctirik); @. without lesions (Kongelaps). of cach group, including the U.S. normal group, had TG values >30 ng/ml, but the significance of this is uncertain. Of 24 sul(e. swith elevated serum joduprotein, only | had .cam TG >30 ng/di. A striking finding (Figure 41) was that in the Rongelap plus Ctirik group with thyroid lesions (36 people) almost 50% of the levels were <5 ng/ml, a much higher percentage thanin the other groups, Most of these people had had prior thyroid surgery or were athyreotic, and itis presumed that they had insufficient thyreid tissue for normal TG production. Furthermore, Ty suppression therapy mayhave contributed to the low TG levels in the Rongelap people. TG was also measured before and after TSH irjection in 10 Rongelap plus Utirik subjects with thyroid lesions and in 20 Ronyclapese with none (Figure 42). la every case, VSI] resuliedina rise in VG tevel, and there was no apparent dillerence between the two groups. The unusually high level ot iodaprotein in the TG/d)), the possibility was investigated by radioimMUNGMcasurements (MM. Lacs, J. Bactieu, Manhallese people is intriguing, and further studies are in progress, with ?="1 used as the tracer, in aa atlempt to identily the protein, * >S ng/ml, levels > 40 ny, ml were not quantivied. ln the Rongelap and Uticik groups without thy. G. CORRELATION OF THYROID ABNORMALITIES WITH RAOLATION EXPOSURE AND J. Ronnins, unpublished observations, 1974; see Figure 11). Vhe assay could detect VG levels roid lesions (47 ard 25 subjects respectively), 2 00% of the values were within the U.S. range, and no correlation was scen between clevated serumjodoe protein and abaornal PG levels. A few members ae SSN ray or em ie Statistics on the incidence of thyroid abnonnalities in people living on the Marshall Islands are Mie (OF, Straub, NT. is chetig the cheiicat analyses. . Af e No lesions (Rongelap) yar * \ fe eeee oe eeee A 1G by RUA (ng/ml) | -cse 14 (Resngrlop + Ciirik)