-2h= - ~. thereof provides an ingestion mechanism which by-passes the root route, I-131 can be detected in thyroids all over the U.S., and it maps out the fall-out pattern, It is estimated that everyone in the U.S, received a dose of 1 rep in the thyroid as a result of CASTLE, Rongelap islanders got 170 r to the thyroid from I-131. The A classifica- tion problem arises in that many people are detecting I-131 from the Russian shots in sheep and cattle thyroids. Dr. Bugher cautioned against the use of milk from heavily contaminated areas. The strontium-90 surveys are: showing a consistent pattern; inSr-90 creasing study is being required. The body appears to discriminate against strontium in favor of calcium; "we are living in a nonequilibrium situation." Sr-90 in the New York milk supply has in- iz creased, There is some evidence from balloon samples for Sr _-.. wea ee —_ rrSagees fractionation, Some overlay maps showing world-wide fall-out (extrapolated to Janvary 1, 1955 by a t71*2 law) were displayed, from 1 to 60 mc mixed f.p./mi*, as dpm Sr-90/ft*.) The numbers ranged (This unit is approximately the same The accumulation in the southern hemisphere, Dr, Fisk observed, seems to give evidence for prompt atmospheric mixing between the northern and southern hemispheres. The fall-out in the U.S. during March 1 - May 1, 1954 ranged up to 100 mc/mi2. Dr. Rabi asked about plutonium fall-out. Pu Dr. Bugher said that it had been detected in land samples after the March 1 shot and in the