It will be noted that no evaluation has been made of the dose

due to 1131, c14, or other radionuclides known to be present in vivo

even very briefly as occurs in the case of non-sssimilated elements passing through the GI tract. As as whole body irradiation is concerned these radioisotopes are of secondary importance compared with ground fallout and internal Ca137 and ar

90

The methodology described and utilised in this work has made it possible to obtain a measure of the dose arising from game-anitting fission activity on the ground. Evaluation of the whole body dose to man from such sources has been made through the use of shielding factors applied to this gamma radiation. The present situation in which nuclear weapons testing is no longer being carried out will lead to a genetic dose of 52 mrads and a lifetime dose of 62 zrais to roughly one-half of the population of the United States, an increase of approximately 1% over that arising from natural radiation. The continuous testing of muclear weapons at the rate occuring between 1954 and 1959 would result in an increase of the whole body dose of 6% over that occurring naturally,

REFERENORS

1. I. G. Stevert, R. G. D. Osmond, R. N. Crooks, Miss E. M. R.

Fisher, M. J. Overs, ABER HP/R 2790 (1959).

2. W. H. Langham and E. C. Anderson,'

"Cg137

Biospheric Contamination

from Nuclear Weapons Tests," Health Five. I. (in press).

3. M. Eisenbud, "Measurements of Strontium-90 in Geophysical and Biological Material," Hearings before the special subecmittee

radiation of the Joint Committee on Atomic Energy, Congress

of the United States, Part 1. pp 554-575 (1957).

4. E. C. Anderson, R. L. Schuch, W. R. Fisher and W. H. Langham

"Radioactivity of People and Foods," Science 125(3261): 1273-78 (1957). 5. W. R. Eckelmann, J. L. Kalp, A. R. Schulert, "Strontium-90 in

Man, II," Science 127(3293): 266-74 (1959).

6. P. F. Gustafson, L. D. Marinelli, and S. S. Brar, "Natural and Fission-Produced Gamma-Ray Emitting Radioactivity in Soil,"

Science 127: 1240-42 (1958).

7. P. F. Gustafson, "The Ratio of Ca137 and Sr-90 Radioactivity in

Soil," Science (in press).

8. G. M. Dunning, Hearings before the special subcommittee on radiation of the Joint Committee on Atomic Energy, Congress of the United States, Part 1, pp 239-40 (1957).

9. B. Hultqvist, "Studies on Naturally Occurring Ionizing Radiations," Kgl. Svenska Ventenskapsakad. Handl. 6(4), no. 3 (1956).

10. Report of the United Nations Scientific Committee an

Effects of Atomic Radiation. General Assembly Official Records: Thirteenth Session, Supplement no. 17 (A/3838), Nev York (1958), 11. W. F. Libby, "Radioactive Strontium Fallout," Prog. Xat. Acad. Hoi., I. 8. 42: 365-390 (1956).

12. E. A. Martall, "Atmospheric Aspects of Strontium-90 Fallout," Solence 129(3357): 1197-1206 (1959).

13. W. F. Libby, "Stratospheric Fallout Particularly from the

Russian October Series," USAEC, TID-5556, May 1959.

14. M. Eisenbud, "Deposition of Strontium-90 through October 1958, Safence 130(3367): 76-80 (1959).

Gamma-Ray Emitting Fallout Radioactivity on the Ground at Argonne National Laboratory

in mc/mi2

TABLE II