~94) Crude as these predictions are, they indicate that much value can be gained from study of the Utah children. If low doses of I?3} are without effect in infants, verification of this hypothesis would be of fundamental importance in understanding the induction of radiation-induced cancer. (Hopefully) never again may 250,000 additional infants be irradiated with E31 and become available for observation. The present study should reach beyond a mere tabulation of possible effects. Its prime objective should be to establish the relationship between dose and damage: this requires atten- tion to the dosimetry in addition to the search for effects. 5) Improvement in dose estimates should not be delayed any longer. The ground fallout pattern should be established for each one of the Nevada test shots (the conventional meteorological trajectories for material passing thousands of feet overhead are inadequate). The actual deposition of fallout should be evaluated by records of field gamma-ray intensities and fallout tray beta-activities, when available. When measurements are lacking, the deposi- tion should be estimated from meteorological considerations. The probable fractionation (depletion or enrichment) of D271 relative to the other fallout products should be determined whenever possible. Possible changes in the availability of fallout particles at various distances from the test site should be considered. From feeding records, the intake of IF'3! by milk cows in each milkshed area should be established. is used). The intake is very low when uncontaminated feed From 3) intake by the cow, I'3? contamination in the milk can be calculated. This should be done, at least for the major dairies. From the daily consumption of fresh milk, the human thyroid dose can be computed. While it might be impractical to reconstruct the individual dose for each person in Utah, this should be done for limited areas, such as St. George. Separation of the infants drinking highly radioactive milk from those whose milk was uncontaminated (powdered, canned or from "cold" milksheds) would provide the internal "control" group needed so badly for comparison. The average dose to infants throughout the rest of Utah could be established by intensive study of a suitably selected representative sample (perhaps about 1000 children). Certainly the individual doses should be reconstructed for all children developing abnormal thyroid conditions to see if their doses differ from the general population's. In dose reconstruction, particular