260 BIOLOGICAL EFFECTS OF IONIZING RADIATIONS 



This is the period of enthusiasm for the use of mustards in this new role 

 (they originally saw service as war gases). As their limitations for therapy 

 become better known, and if history repeats, both the new chemical therapy 

 and ionizing radiation therapy will oscillate through periods of enthusiasm 

 and reappraisal before ultimately finding their proper place in the medical 

 arsenal. 



The reader may now wish to pursue the subject matter of this chapter in 

 more detail. The author suggests perusal of References 28 and 23, then of 

 References 10, 1, and 2. 



PROBLEMS 



9- 1 : (a) From tabulated values of the sensitivity constant, a, estimate the dose which 

 would be expected to kill 20, 50 and 80 per cent of a tumor. 



(b) Suppose this tumor were just under the skin. Discuss three different ways 

 — ultrasonic, machine-made X-rays, and cobalt-60 gamma rays — in which 

 you could apply the irradiation. 



(c) How would you monitor the air dose? The tissue dose? 



9-2: How do you rationalize the facts that X rays induce cancer, and that X rays are 

 used in the treatment of cancer? 



REFERENCES 



1. Alexander, P., "Atomic Radiation and Life," Penguin Books, Inc., Baltimore, 



1959: a "popular" introduction to the text, Ref. 2. 



2. Bacq, Z. M. and Alexander, P., "Fundamentals of Radiobiology," Butter- 



worths, London, 1955; 2nd ed., 1961. 



3. Hollaender, A., Ed., "Radiation Biology," McGraw-Hill Book Co., Inc., New 



York, N. Y., 1954. 



4. Oncley, J. L., et al., "Biophysical Science — A Study Program," John Wiley & 



Sons, Inc., New York, N. Y., 1959; especially the contributions by R. E. 

 Zirkle, W. Bloom, E. Pollard, T. H. Wood, C. A. Tobias and T. T. Puck on 

 radiation effects. 



5. Livshits, N. N., "Physiological Effects of Nuclear Radiations on the Central 



Nervous System," in Adv. in Biol, and Med. Pkys., 7, 174-241 (1960): a review 

 of the extensive Russian work, and that of others, on this important question. 



6. Law, L. W., "Radiation Carcinogenesis," ibid., 7,295-337 (1960): a penetrating 



survey of recent work, and a lucid account of the present position of knowledge 

 on radiation-induced neoplasms. 



7. Howard-Flanders, P., "Physical and Chemical Mechanisms in the Injury of 



Cells by Ionizing Radiations," ibid., 6, 554-596 (1958). 



8. Kinsman, S., Ed., "Radiological Health Handbook," U. S. Dept. of Health, 



Education and Welfare, 1954. 



