risk of developing these conditions through the year 2000. Inheritable, genetic, effects may have resulted and would be expected to be expressed most frequently until 1980. Expression could continue throughoutthe entire period until the year 2000 and beyond, but probably not in sufficient numbers to be detected in this small population. Leukemias, other than chronic lymphocytic leukemia, would be expected to have resulted up until 1980, and possibly beyond. To date only one case has been observed in the population. Bone marrow depression, aplastic anemia, and male infertility would be expected to be diagnosed, if present within the first five or ten years, that is until 1965. ~ 45.5.2. Medical Conditions Possibly Related to the Radiological Exposure Medical conditions possibly related to exposure to the types andlevels of radiation experienced in the Marshall Islands include: Benign breast tumors, cancers of the brain or lung, immune system deficiencies, all of which could possibly appear, as far as is known, throughoutthe entire surveillance period. Cancer ofthe breast, vascular sclerosis (fibroatrophy), leukemias in the second generation, if caused, would be expected to be seen beginning in the 1961 to 1965 five-year period Ci p.3 Ey oo and continuing through the year 2000.