-2absosped v2 from che 1 fallout vas not reclized at that time, perticulerly jn the children, ard so thyvoic €° tects werc not anticipated even in the Rong3 elap group. In retrospect this is nct surprising sinec onl; relovively re- cently hes the degre of sensitivity of the thyroid, particularly in chile- ‘ren, for the development of radlation-induced tumcrs begua to be sporeciatcc. It is likely that the Unitcd States populations with thyroic enposurc have not been as carefully fol’ owad as the Utirik population. Controlpreups In 1954 an uncsposed group of the Marshallese people living et Majuro was ‘ixst chosen as a control group, but this group proved vasatisfactory and in 1956 a control po; ulation of some of the unexposed Rom: lan pewnle was establish2". These people were relatives of the exposed srov> and con- Listed of 40-200 peLOL Ie. This sroup is considered quite accquate as a con- trol group for both Rongselap and Utirik people. The slight differences in ethnic background betveen ile twe populations d‘¢ not constitute vcasons for baving separcte control grouns. Chile: cn_of ex -osedparents: the children of the exposed islanders have not been included on the regular examinaticn list. This has net been considered necessary since siudci - of co..siderably lerger groups of children of exposed paresnts in Japan have not revealed any clear-cut genctic effects and it was therefore felt thet such studies on the Marshallese children were not indicated. Thoush the children have not been included for regular examinations they are examined and treatThe leck o Kh ar sun Coll ed, during the visits of our doctors to Utirik and Rongelap. in- clusion of children of cxposed on our examination list has been tne cause of considerable unrest among the exposed people. the ERDA stand on this issuc, . (en feet) Enclosures 1] and 92 present