CONTENTS (Cont'd) Page ¢. The Buildup of BRAVO Fallout on the Ground .....-.+.. e. Activity and Exposure-Rate History Based on Bikini d. A Simple Model for Exposure-Rate History at Rongelap, Sifo, and Utirik Islands ...cccscccccscvesssscseces ASH wcccccrcscccc tere secererseeesecseesccscesesssece i. Areal Activity and Exposure Rate from Nuclides Observed on Day 26 wceosccccccccecscccccssese ii. Areal Activity at Fallout Cessation ...cseccses iii. Areal Activity of Nuclides Without Descendants iv. ve vi. in Bikini ASH wcsccccncccccnnccecscsssscscess Non-Fission-Fragment Nuclides Not Accounted LOT scocccccccenscccscscevorescceenceseseueces Input Data to Kinetics Equations ...ccccenvceee Exposure Rate on Day 0.5 and Surface Roughness Effects vii. ames et tII. eee 30 31 32 37 38 38 39 Radioactivity in Food, Water Supplies, and Air ...seceoee eaenpneaeeaetevp cosa swpaeveepeeaeceseeceseoaoeeoev esc eoeveneeveewvepeoesneen 39 b. Activity Ingested with Drinking Water ....scscocceees 42 Total Activity [ntake ..cccccrcccccccccvescscccevcese Deriving 131r Intake Based on Bikini Ash, 89gr, and !4032 in Urine on Day 45 Post-Detonation ...+.Absorption Through Skin ..ccccsccccescsccncsccccccces 54 a. Activity in Cistern Water ..ccceseseseseccscccecesess Ce. d. e. f. Activity Activity Activity Activity 1. ; eeeea 30 © Ze. he 3. eee 28 Integrated Exposure and Whole-Body Absorbed Dose 2. seeeeeceeseoaeetoesposeeceoeecaepaeseeeeeae 22 in Pood wescccsccrcsccccccsscccscscssccccccs Ingested with Meals ...cccscccccevesssesceces Concentrations in Air .ccccccccccccccssscses Intake by Inhalation ..ccscscccccccscsscesee 39 44 45 IZ 52 54 57 Absorbed Dose for Individuals ..ccccssnccssccccscccsveves 57 c. d. 60 60 a. b. Absorbed Dose per Unit Activity Intake .....ccesceeee Thyroid Absorbed Dose ...ccccnccrccccccsccccscneveses Maximum Thyroid Absorbed Dose ..cccncevcscnccccccecee External Sources of Thyroid Dose ...ccccsescceseceees 57 dF Thyroid Nodule Risk and Thyroid Cancer Risk from Exposure to Fallout eeseoeeepeeeev ease eee ee esses eeeeeeaeeeeseeeeesceeeeesevneensvnes eee s 62 A. B. Tabulation of Thyroid Effects and Age at Exposure ..cccsceees Tabulation of Risk of Thyroid Cancer .sccccssecncsssccsesesss 62 62 D. Estimate of the Uncertainty in the Derived Risk Estimate ...-.- 45 C. Comparison to Other Estimates of Risk of Thyroid Cancer ..... -~ viii - 62