net very reliable. Fram our surveys of the anes: posed people af Rongelap and Likiep (a nearby atoll not exposed to fifloud, the tacidence appears w be about S°einosthy present in alder are groupes gee Figure 29 and Table 25). We lave seen alew cases of hvperthyvroidisin and ar sedeniaa at dhe Majure Plospital. but no starsties ave avatlable. Teo qises of thyroid Cancer are reported trans hospital adiniasions for a TO- ear period (iol. 12) for the Marshall [Mands. the populatios watson between 19.000 aad 20000 darting that period. Vhis has beeu esdanated be Prast Perritery maedical personne) to be about boll che aetiaad number af cases: (therefore 8 Gases por JOH people per 20 years wars used lor statisiiih eon pPAIrisanis }. Data on iodine intake and exeretion ins the Marshallese (tabulated below and presented in detail ing Appendix 9) indicate that todine-deti- cieney goiter would aot be expected ta this population, Sample U6 Urine TW Uranes 7 ets fos char gat edt toate,awrae day ciatige) Wi Pe S704 27 (l5- 2h TU (ABDy The urinary iodine excretion is somewhat lower than the US. mean of 190 we day C1H-485) in PH! Ono the basis of the fewdiets analwacd, the daily ioding intake seems to be within the recana- mended range of 50 to 73 we.Vhese iodine levels are somewhat lower than would be expected nan oceanic population but are auch higher than seen in areas of endemic gaiter#® Vhe NGushaltese dict contains ho know gotrogens, and diffuse gouters (typical af endemig goiter) awe not been observed. Vhe high incidence of both benign and malig. nant thyroid nodules an the exposed Rongelap people appears to be clearly related to radiation exposure with a large compenent due ta racdio- lodine an the fallaui, Numerous squdies aa aniinads have shown dhat theroid neoolasia follows expo. sure both to w-ipradiadion and to radiotodiaes Suc htumars may be benivn or madignant and ap- pear to be dose-dependent to some degree. The incidence of thyroid funors is increased in fap- anese atom bomb survivers!' 2! (Figure 44). ‘Vhere ts. a considerable amount of data showing that children who were given radiation to the head and neck region for teeatiment of ghveate livper“Thr etic Dati ai NT, arabes were clone: diy MT I Roasles and PF CD Uitewtatiae CT Naaewaht | Nook ub cubs baw Tite Lietchew Pigure B38. Pros adence of disies et the tha res fifth es. aligticationss © vad, Lex rucbiotsed: chose snare cata fot fetaeles age (te P94 at time ot banda. (Prone Belskes et ab is, trophy, sone, and fungus of the scalp have an ba. creasce anecidence of bath benign and amaligiaue thyroid lesions in biter years Report of hamorivenie effec of radioiodine ta aaa are more Hiited. Sheline et alt in their follow-up study of 250) patients treated for hyperthyroidism, re- ported & having nodular goiter, of whom 6 had been irradiated atyve O20 and boat awe << 10, More recently a nuiiber of caneers of die thyroid have been reported in patients previously treated with radioiodine for hyperthyroidism. bee Phe nutuber olsuch cases reported is, however, lower Than ight be expected an tle basis of the wide: spread use ol FUT, pechaps because rhe cells aire mare likely to anderwo tocbal damage, 14-22 Tn the nore heavily exposed Rongelap ureup the adit thvrotds received a dose (40 racks) attenat twice that te the whole body and those of small children (700 co TEGO rads) about & ues chat bo the whole body. Qui the basis af the aieidence af benign nediiles in the unexposed Marshall than populations examined. about J tod cases would be expceted during the 20 vears in die Rengelip ex: posed vroup, whereas 2 baccurtred. Gnthe Cririk group about Ga would be expected. and b occarred, Rewarding cancer of the therord, on the basis of Miaarsthall Islands statistics. abennt G05 cases would be expected in the Ronaehap group aver the 20year period, whereas S$ occurred. En othe Cririk population about 0.06 cases wauld be expected, cd Peccucred: bao viewat the baw dose ef radia don itis untkely that this case is radiauan iduaced. Tables 34 aod i} show the incidence and the risk per rad ing tac Marshallese compared with that ia ather populations for bath benigu ane oa. iignant thyroid neoplasins. Data on benign tiv rotd nodularity are scarce, but the incidenee in