Table I Ratio of Doses for the Two Modes of Intake Inhalation Last Oral Ingestion ere Lys 0.148 Decay 0.68 0.31 0.487 Fission yie1d®™ 1.38 1.23 1.38 Energy 2.00 1.50 2.00 1.50 1.85 0.57 1.35 0.27 Net Factor The dose to the t yroid in rads from all three isotopes is, “4 ere rhys, 1.23 | 3.4 times the dose due to I alone for jnhalation and 2.6 times the I dose for oral ingestion. Delay in reaching the thyroid aftes inhalation or ingestion,would lower these factors somewhat. However, the I daughter of the 78 bs Te bas been neglected and would approximately compensate for decay of I and I before reaching the thyroid. We can now proceed to estimate the dose to the thyroids of 3 - 4 year old girls-assuming (1) 1. Inhalation: inhalation as the mode of intake and (2) oral ingestion. The ratio of volume of air respired by a 3 - 4 year old girl to that of an ady 5 can be estimated in two ways: (22) from the maximum rate of oxygen intake and (b) from the vital capacity and maximum respiration rate, Both methods give a ratio of _0.3. The thyroid burden of these children would then be ~3.4 uc with a range of 1.7 - 6.8 uc. Assuming the Rongelap children are similar to those of New York (9) children, the mass of the thyroid of the children is 2.5 + 0.6 grams. The most probable dose from 131, is then 150 rad and the dose from all isotopes is 510 rad. If we consider the range of thyroid burden (1.7 - 6.8 uc) andthe variation in thyroid weight (1.9 - 3.1 gms), the dose is in the range of 200 - 1350 rad. 2. Oral Ingestion: At the time of the event the Rongelap people were on a water ration of one pint per day. They were warned not to drip water after the event but most of them admitted they drank water anyway. The method of collecting water by runoff from roofs into cisterns makes it very likely that this was the main source of oral ingestion. There are reports that it ‘rained a little" on the afternoon of March 1 (D-Day). The village doctor reported that the "water turned yellow.'"' As far as food is concerned, the most likely source is dried fish. Fish were dried on open racks. However, in the interviews none of them listed dried fish as having been eaten during 81