Monthly Status and Progress Reports for March 1953 (Partial) (Sec. V, Biology and Medicine Only)

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Weapons Test Activities A new office has been activated under the Test Organization during the spring, 1953,'test series to provide technical guidance (in an advisory capacity) on fall-out problems,-and to assemble, evaluate, and interpret all fall-out data collected by the various test monitoring groups. quantitative data become available, evaluations and interpretations are made of the results. channels for ,immediate public release. . sible to allay public alarm which might have resulted from erroneous speculations; to keep the Commission and all interested groups currently,informed; and to assist in maintaining sound and effective public relations. As a part of this program, cooperation of the U. S. Public Health The information is then relayed through official In this manner, it has been pos-. Service has been obtained in interpreting to the public the health aspects of fall-out. To assist this group, scientifically qualifipd personnel were designated at ten AEC installations throughout the country to provide authoritative sources to whom Public Health officials could turn for specific or general information relating to fall-out. Members of both groups were notified through the Nevada office whenever their axeas were likely to fall in the path of expected fall-out activity. (End of' UNCLASSIFIED Preliminary data on fall-out studies from the first detonation of the current the Nevada Proving Grounds occurred in a relatively narrow band almost due east, stretching from about 50 to 200 miles, from point zero. of activity were relatively high but did not exceed the maximum permissible *exposure at any populated area. The highest calculated gamma dose for populated areas was at Rockville, Utah, where the estimation was about 2 roentgens for a ten-week period. But even this level has built-in safety factors because it assumes: (1) that people remain in the locality continuously; (2) that none of the activity is lost through weathering; and ( 3 ) that there is no attenuation due to intervening walls, floors, etc. The above 2-roentgen calculated dose therefore represents the extreme estimate. The fall-out from the first shot provided a good opportunity to check the effect of weathering on activity since the fall-out area was concentrated in a narrow band. A l s o , on the second and third days after . detonation a strong wind blew across this area. Monitoring teams returned to the fall-out area on the fourth day after detonation and checked the actual radiation levels with those that were calculated from the reading of the first day. The actual readings on the fourth day were lower than calculated readings by factors of 3 to 6. The fall-out following the second detonation on'March 24 occurred ' to t h e northeast from the test site. The locality receiving the heaviest

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fall-out w a s Lincoln Mine where there are about 300 people living at present. Here the activity rose t o about 600 milliroengtens per hour at2 hours after detonation. people at the mine were advised by the Test Organization t o remain indoors. Approximately 2 hours later the people were advised t h a t they might go about their normal activities but t o remain indoors as much as feasible during the remainder of the day. Lincoln Mine, based on the same assumptions as above, is about 3 roentgens. Since the fall-out occurred so soon after detonation, it i s estimated that 1 roentgen of this dose was accumulated i n about the first 8 or 10 hours. Readings taken both indoors and outdoors indicate that the former levels were tibout 35 percent of those found outdoors, and thus, of course, the accumulated dose t o those remaining inside would be l e s s than the aboveThe calculated ten-weeks' dose at A small amount of fall - out which occurred in.the.Salt Lake CityOgden region about 14 hours after detonation reached a peak of 4.8 milli - roengtens per hour. This quickly dropped, so that 45 minutes later the. reading w a s about 0.7 milliroengtens per hour and then continued t o decrease at the usual rate found during fall-out activity. same assumptions as above, the calculated ten-weeks' dose i n these areas i s about 40 milliroentgens o r 1.3 percent of the maximum permissible Based on the Civil effects test program. While analysis of test data has not This preliminary result tends t o been completed, it appears that predicted blast pressures were achieved inside the communal shelters tested. bear out the accuracy of the shock tube t e s t s of scale model shelters conducted at Aberdeen Proving Ground earlier i n the year. is reason to think that these blast levels heretofore considered acceptable may have t o be modified downward, with further redesign of shelter entrances, i f subsequent analysis of the animal experiments verifies sdly indications of effects somewhat more severe than expected. @h+ A s has been reported earlier,Telemetering program remotely controlled radi a tio d weather reporting instruments, which telemeter data by radio t o a central control point, a r e being tested during the current test series. the vicinity of the three experimental stations, accurate weather and fallout data have been reported i n advance of reports received from mobile from the control point, and surprisingly good results have on occasion been obtained up t o 70 miles away. than had been considered practical prior t o the tests. While only three stations have been employed i n the experiment t o date, multiplication of this number by a factor of three, or thirty, or a hundred may be feasible. By the use of more powerful transmitting or relay techniques, or by hooking the system into telephone pairs, it i s theoretically possible t o cover a 200- or 500-mile zone quite as effectively as the present high-cost, To date, where fall - out has occurred i n Excellent reception has been obtained up t o 25 miles Thus, it would appear technically - feasible to locate stations at greater distances from the control point

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multiple-manpower mobile teams. One of the advantages of the telemetering system, readily noticeable during the recent tests, is that the peak in a man-hours is reached prior to the detonation, rather than immediately folof radiological activity immediately after shot time, the telemetering crew can sit back and wait for the telemetering stations to report in. The stations can also be interrogated by signal impulse, responding with wind velocity, wind direction, temperature, humidity, and so forth. The risk of over-exposure to radiation, always present in mobile operations, is practically eliminated. As a result, while a flurry of activity ensues in other branches Industrial Health Program (UNCLASSIFIED) Improved chemical dosimeters. Under a cooperative program with the National Bureau of Standards, evaluation tests of new radiation detection instruments and their performance characteristics are made conbeen tested for calibration and rate dependency. under the AEC project at the University of California at Los Angeles, is a two-phase system,consistingof water, chloroform, resorcinol; and a dye minute were administered during tests. The results to date indicate that the dosimeter response is not significantly dependent.on the rate at which the radiation is received. dosimeters useful in measuring high intensity gamma radiation such as the prompt radiation from an atomic bomb explosion. general consistent within color comparison device of this type. Under this program an improved chemical dosimeter has recently This dosimeter, developed Exposure rates up to 4,000 roentgens per This 1ac.k of rate dependency should make the 'e The readings were in 20 percent, which is very remarkable for a Sensitivity of lymphoid tissues. At Northwestern University . Medical School researchers investigating methods for separation of various components of lymphoid tissue have isolated a protein in the cytoplasmic nucleoprotein fraction which has unusual sensitivity to ultra-violet light and to alkalinity. This study is important as very little is known about the cornpsition or properties of lymphoid tissues which are involved in many resgiratory infections and presumably influence virulence and growth Since lymphoid tissue is known to be highly sensitive to radiation damage, this finding may prove very , significant, and further study is being made to define the function of the protein in relation to radiation sickness. Protective effects against X irradiation. Studies under way at the University of Southern California point to the possible protective ' BFfects ggainst X irradiation of fat content in diets.. Experiments have mwn that rats receiving a diet containing a small amount of cottonseed 6il were much more resistant to injury from X irradiation than were sni- %en anirals on these dietary regimens were subjected to repeated sublethal -E s e s of X irradiation in amounts of 380 roentgens at sreekly intervals. A marked variability in survival time was noted

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It was found that the animals i n which fat was present i n the diet lived significantly longer than the group receiving a fat-free diet. examination, it was shown t h a t the protective action was afforded by the presence of methyl linoleate, a normal constituent of many fats and o i l s . This fatty acid i s considered t o be an essential constituent-of the diet ; as little as tenmilligrams per day of this ester afforded significant protection t o the X irradiation damage. It is felt ,that the protective action may be related t o metabolism of the skin as it i s known that highly unsaturated fatty acids as linoleate play an important part i n such metabolism. Somatic mutation program. I n cooperation with various agricultural experiment stations, Brookhaven National Laboratory has initiated a program using the gamma radiation field for the induction of mutations in fruit trees or other plants of agricultural importance. The value of t h i s program has been widelyrecognized and already a number of Eastern experiment stations have sent t o the Laboratory trees and shrubs which have been s e t out i n sectors at selected distances .from. the cobalt 60 . flowering plants have been set out i n the field so that they are exposed t o chronic radiation, the dosage depending on the distance f r n m the source. Mutations induced by the radioactivity may be expected t o appear i n buds a t any level of growth of the t r e e or plant. Later, cuttings can be transferred as scions t o other nonradiated plants a t the<homeagricultural staand plants, it is hoped t o develop new and commercially valuable varieties which the ex2eriment stations can make available t o the public. Mutations may be expected also i n the seeds, but it takes very much longer t o grow and t e s t these germinal mutations than the somatic variants. The trees or shrubs ranging i n age frorn.seedlings t o mature By such large scale irradiation of many ds fe rent kinds of trees ' 0' Abnorqal growth induced by radiation. An interesting and somewhat unexpected result of chronic irradiation in the gamma field at Brookhaven National Laboratory has been the observation i n the spiderwort Tradescantia of mzrked abnormal overgrowth of flower heads and the presence of many abnormal buds on the stems. between 12 tind 37 roentgens per day of radiation. growth i s normal, but growth decreases above the range. With dosages of approximately 100 roentgens, complete inhibition occurs. The appearance of these abnormally growing plants i s very different from the norual. Normally, the first to third auxiliary bud grows intoa single flowering stalk, and buds at lower nodes are inhibited. I n the critical dosage range cited 3.bove, from four t o f i v e auxiliary buds develop shoots forming a mass of fused or dissected leaves. These then grow out into single or multiple vegetative shoots, and each sends out a short flower s t a l k beaxing a normally appearing flower head. Cuttings from these plants grow normally, showing that the abnormalities are due t o physiological disturbances (perhaps zuxin synthesis which inhibits growth i s disturbed) rather than t o mutation. These appear on plants receiving Below this range the (End of UNCLASSIFIED section.)