65 Hematogical Effects on Heavily Irradiated Japan ese Fishermen STATE OF IRRADIATION AND ESTIMATED RADIATION DOSE | N HEAVILY ‘SHERMEN The fishermen were irradiated in the following 3 avays: (1) From the radioactive materials adhering to the body surface. (2) Externally from the radioactive materials deposited in the cabins, on the decketc. (3) Internally from the radioactive materials entering various organs. The diameters of the fallout materials, which were the powders of coralreef fragments, ranged from 19 to 460 4, mainly 100 to 400 4 (Kixvcni et al, 1954). According to the results of radiochemical analysis of fallout on 26 March, rare-earth elements contributed about 50 per cent of the total radioactivity and uranium contributed about 20 per cent (Kimura et al., 1956). The specific activity of the material was 0.37 mCi/g on 23 April. By extrapolation of these data, a value of 1.4 Ci/g was obtained as the specific activity at 7:00 osion was performed by e Pacific Ocean. At that aru” was located at about S nearly 100 tons and 23 in fishing tuna they saw ion several minutes Jater. vhich continued for ap- returned to their mother have been injured by the ed to the Tokyo Univer> First National Hospital u both hospitals in May ember 1954. After being ar as possible on annual of their occupations and sible to get them all to-d several times (Miv osw t al, 1956; Miyosiy and HY and KUMATOonRI, 196 4. “RIALS Ss intensity was Ereate st, “yes open. Their foo t- Wlout. a.m. on 1 March. The estimation of radiation dose, especially that from internally deposited radioactive materials was difficult. However, radiation from body surface was large enough to cause skin lesions. External radiation dose was estimated as shown in Table 1. The exposure dose for 14 days ranged from about 170 to 690 R, and nearly 60 per cent of these doses was received on the first day. This estimation was based on the results of the experimental reproduction of ash-fall, extrapolation of decay curves of many places of the boat, and on detailed investigation of Table 1 Subject No. Estimated dose of whole body gamma radiation. First Day Total T-1 T-2 T-3 T-5 T-6 T-7 T-3 240~290 R 210~260 150~200 400~-430 130~180 140~190 310~360 450~500 R 390 ~-440 260~310* (360~—410} 660 ~ 690 200 -~250 -220~270 520~570 K-2 K-3 K+ 130~180 140~190 120~170 200~250 230~280 190~240 K-1 K-5 K-8 K-7 K-8 K-9 K-10 K-ll K-12 K-13 K-14 K-15 K-16 190~220 140~190 180~230 230~280 220~270 310~360 140~-190 120~170 100~150 250~300 420~500 140~190 120~170 310~340 220~270 300~350 340~390 380~430 550~600 230~250 170~220 170~220 370 ~420 510~-590 210~ 260 190~240 * T-3 put the fall-out material close to his bed. Therefore about 100R should be added in total.