2 WORLDWIDE EFFECTS OF ATOMIC WEAPONS necesPrevious estimates of the number of bombsor of thetotal yield inned contai have effects erm long-t and cale sary to produce such large-s in wns unkno cal biologi and l physica herent uncertainties because of the effects their and ts produc the complicated history of radioactive fission ance in on man. These uncertainties did not seem to beof critical import tably comfor d the past because the minimum estimates of yield require with exceeded the total yield of nuclear weaponsdetonated to date. Now, ing increas s world’ the of e becaus and the advent of high-yield bombs less is but large still is es stockpile, the margin over the early estimat inties by a clearly definable. It is most desirable to lessen these uncerta an effort concerted attack on the problem. Project SUNSHINE” represents fields by RAND with the support of many of the leaders in the appropriate experit explici an t waytha of science to formulate the problem in such a ry for a mental program may be undertaken to provide the facts necessa more reliable estimate of this large-scale hazard. INTRODUCTION AND CONCLUSIONS 3 (a2) Products dependent on the composition and nature of the device itself. (4) Induced activities dependent on burst environment. Project GABRIEL concluded that the most dangerous radioactive product is strontium 90 (Sr°°), one of the most abundantly formed products of a fission reaction. Later studies by the Atomic Energy Commission's Division of Biology and Medicine corroborate the identification of Sr°° as the most important long-range contaminant. These conclusions were established mainly as a result of the following properties of Sr°°: 1, A nuclear detonation will produce 1 gram (gm) of Sr°° per kiloton (KT) of yield energy, or 20 gm per 20-KT “nominal” bomb. This is a considerable quantity. 2. Its physical half-life is long-—20 years. 3. It possesses a long biological half-life because of its bone-seeking property. 4. Body ingestionis high. THE LONG-RANGE RISKS has Man, in his development of more “efficient” means of waging war, s. Now, in often increased the incidence of casualties to noncombatant -type casualatomic warfare, there exist means forinflicting noncombative Le., through s, weapon of ties long after the detonation of a number radiative damage. ate effects The hazards existing near ground zero following the immedi l radiation; of a nuclear detonation consist mainly in exposure to externa The main reports. weapon many these hazards are covered in detail in tive debris that, concern of SUNSHINE is to examine the hazards of radioac thereby by one means or another, finds a way into a human being and may be becomes a source of internal radiation damage, this latter hazard expresent in relatively local areas of the earth or may be spread more man. of ce commer pesivel eatiralthrough the device can The radioactive debris resulting from the burst of a nuclear be classified as follows: “short-range” evaluations of *Project SUNSHINE is to be distinguished from the separate effects. fallout e close-in, short time-scal Project SUNSHINE has further concluded that the manner of production peculiar to this contaminant suggests that it will be readily available for incorporation into the biosphere. Consequently, at the present writing, we concur that Sris the principal long-range, possibly worldwide, contaminant. Studies are being continued to determine whether or not any other products under both (a) and (4) above may present a biological hazard comparableto or larger than that of Sr°°. Possible substances may be certain isotopes that are formed in fairly large quantities in thermonuclear bursts. For lack of data, several problems are not discussed in this preliminary report but are the subject of current study. They include the problem of what role the hydrosphere may have in the disposal of radioactive contaminants, the effects of the contaminant on life in the hydrosphere, and human dependence on its products. The proposed sampling program is this aspect of the problem. Another problem is ecological in nature. It asks the question, What is the effect on other forms of life as a result of the decrease in population of a given biological form through the action of Sr°°?