[veteran] might have developed leukemia from his Hiroshima experience. He said that one could wonder about the incubation period and how long the disease might take to develop but that the onset of the illness would probably never be well decided. He doubted if the veteran carried the disease for years in the sense that he felt badly from it. The doctor reported that other than the most recent symptoms of infection, bleeding and anemia which occur, any earlier symptomsof leukemia would be purely speculative. In July $970, a medical doctor, Chairman of the Division of Medicat Sciences, National Research Council, advised the Veterans Administration that six weeks had elapsed between the bombing of Nagasaki and the veteran’s disembarkation there and that the chance he was exposed to prompt or induced radiation from the atomic bomb detonated over Nagasaki on August 9, 1945, was most unlikely. On appeal, the appellant’s representative suggested that the independent medical opinion obtained previously by the Board of Veterans Appeals is out-dated, is negatively speculative and does not resolve ali reasonable doubt in the appellant’s favor. Findings of the BVA and Basis for Decision: The Board denied service connection for the reasons that (1) chronic leukemia was not incurred in or aggravated during active service (30 USC 310); (2) that chronic leukemia was not manifest to a compensable degree within one year following the termination of World War IT service (38 USC 312, 313; 38 CFR 3.307): and (3) that a service-connected disability did not cause death or contribute substantially or materially to cause death (38 USC 410; 38 CFR 3.312, 3.102). In finding no probability that the veteran’s leukemia was causally related to any exposure to radiation during military service the Board said: In the past, the question of the possible relationship of lymphatic leukemia to alleged exposure to radiation after the atomic bomb blastin Nagasaki and Hiroshima has been the subject of submission to independent medica! experts not associated with the Veterans Administration, One renowned specialist has been consulted on several The specialist went on to say that no case of leukemia has been known to have developed with acute whole body doses of less than 100 r and that protracted radiation is even less effective than radiation given as an acute dose. It was concluded that there is an increased rate of leukemia at Hiroshima and Nagasaki among Japanese who were exposed to the gamma and neutron radiation received at the time of the bomb — explosion. However, there is no excess of leukemia as compared with the rest of Japan among those living in Hiroshima or Nagasaki who did not receive direct radiation from the weapons explosions but who received slight exposure from residual radioactivity. The independent medical expert has given the official measurements of radiation in Nagasaki which is the accepted basis for calculating dosage there and for determining whether or not the radiation could have been Jeukemogenic. This is, of course, as valid today as it was in 1945 after the explosion and in 1962 when presented to the Veterans Administration, Returning to [veteran’s} case, he did not arrive at Nagasaki until September 23, 1945, about one and one-half months after the atomic bomb explosion there. Therefore, he certainly received no direct radiation from the explosion. At the most he could have received only slight protracted radiation exposure. Inasmuch as there is no excess of leukemia among those persons fiving in Hiroshima and Nagasaki who did not receive direct radiation from the weapons explosion in August 1945 but who did receive extremely slight exposures from residual radiation comparable and probably in excess of those of the veteran, there is no reasonable probability that the veteran’s leukemia was due to the effects of tadiation exposure or was attributable to the period of military service. The disease was first shown about 24 years after the date of his discharge from service. This is too remote from the period of service to be significant in the present case. occasions, including recently. He has been one of the medical directors of the Atomic Energy Commission, a member of the Committee on Atomic Casualties of the National Research Council and a representative of the United States on the United Natians Scientific Committee on Effects of Atomic Radiation. The specialist has stated that fission products from the explosionat Nagasaki were carried over the hills and deposited to some extent in the area around the Nishiyama Reservoir.'A rough fallout track could be followed for some 30 miles to the east but at barely measurable tevels in September and October of 1945. At different times readings on the edge of the harbor in Nagasaki were barely elevated above background (0.05 micro-microroentgens/hr.}. The specialist reported that the effective exposure time of one who workedin the area of highest exposure for 20 hours per day from mid-September to mid-December 1945 would be less than Sr. The series of typhoons and heavy rains in the fall of 1945 reduced the levels still farther. 20 21