-?2from exposure, indicating that the exposure must have been considerably less than was seen on Rongelap island. Following the return to the island, it was decided that regular medical examinations of the exposed people of Utirik were to be done. Such examinations conducted at regular intervals were conducted to assure that they had not been harmed. 1959, 1963, 1969, 1972 and 1975. Examinations were done in 1957, In addition to complete physical examinations, thyroid examinations and sick calls were held every year. Also, in recent years there have been doctors visits to Utirik every three months. In conducting these medical examinations, a control group was selected so that the doctors could compare exposed and non~exposed people. This control group consists of unexposed people from Rongelap. This group is considered quite adequate for comparison with the exposed people of both Rongelap and Utirik. The slight genetic difference between the two populations was not considered a sufficient reason to select a separate control group for Utirik. One of your questions concerned the fact that the children of the exposed islanders have not been included in the regular examination list. This was done because large groups of children of exposed parents have been studied elsewhere. Since none of these studies revealed any distinct genetic effects, it was felt that such a study of the children on Utirik was not necessary. Of course, children are examined and treated as needed at sick calls whenever the doctors visit Utirik.