398 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1963 



ically most similar to sea-water salts, such as radioiodine and 

 radiocesium, give the poorest results in decontamination tests. 

 Eecycling of the water with a different floe producer gives better 

 results. 



From reports of fallout distribution near the Eniwetok test site, 

 it may be assumed that exchange processes will bind mixed fission 

 products for less than 1 week in the open ocean. The data from 

 Project Wigwam, of the Atomic Energy Commission, indicates that 

 this period would be long enough for oceanic processes to disperse and 

 dilute the radioactivity to a point of no hazard following a predictable 

 peacetime accident. In estuaries and coastal waters, the temporary 

 bonding may facilitate beach contamination. 



Particulate feeding organisms, especially oysters, secrete mucus in 

 such a way as to entangle particles in a sort of rope which they may eat 

 or bypass to the open ocean. The mucus-bound material seems to be 

 subject to less rapid chemical exchange, thus permitting more time for 

 radioactive decay to reduce the hazard. In areas contaminated over 

 oyster beds, it should be possible to substantially reduce the direct 

 hazard, but the oysters would be contaminated. 



The ocean offers certain survival advantages to man in case of 

 nuclear war, since within a few hours, dilution would bring the levels 

 of radioactivity near the water surface to a level much lower than on 

 land surfaces where the isotopes would be concentrated in the first 

 centimeter of soil. In addition, since water is an excellent shield for 

 protection from radiation damage, pelagic fish are likely to be the 

 least harmed of all natural resources. During the early fallout 

 periods, it would be possible to pull water from below the surface 

 for washdown decontamination of a ship, and thus lower the total 

 exposure of ship's personnel. 



PROBLEMS NEEDING FURTHER STUDY 



Although much has been learned about waste disposal in sea water, 

 the initial effort has more clearly defined the problem than solved it. 

 The Atomic Energy Commission, the Public Health Service, and other 

 agencies have initiated studies designed to clarify the role of atomic 

 and other wastes in the environment and how they may affect man's 

 health. 



Physical problems of turbulent diffusion and the circulation and 

 residence times of water masses are of significance. Studies of the 

 chemistry of sea water and the biogeochemical relationships involved 

 in the sea water-sea floor interface must be continued, since not even 

 the exact composition of sea water is known. Many naturally radio- 

 active isotopes are present in sea water, and studies of their distribu- 

 tion and reactions contribute to an understanding of the added 

 material. 



