. + ee Ree upeig = ae Se EVFECTS OF IONISING RADIATION to radiation than brunettes (is). Lastly it is quite evident that sensitivity and response varied with anatomic location. In Table 4.3 are listed the approximate sur- face skin doses required to produce recognizable epidermal injury from beta radiations in ani- with hentones in the expowed individuals in this study in order to esimate the sin dow, since specter differences in renponne may exint. ane certain radiation factors are not well extab- Itahenl, suck as accurate knowledge of the beta spectrum of the fniious maseriai and tiem ce. Cotaparwmeon with human data suffers from: wide differences in radiation energy and doves reported and metheds of determining the rep dower. The low incidence of infection of the radia- tion burns is probably due to their superticial nature. Ulceration and partial healing preceded the time of minimal granulocyte counts. It is conceivable, however, that with higher Table 3.3.—Surface Doses Required to Produce Recognizeabie Epidermal lajury (N veeraos ANi@aL Henshaw, et al (22) Raper and Barnes (23) Raper and Barnes (23) Snider and Raper (24) Raper and Barnes (23) Rats. Rats . Mice .. Mice Rabbita Tuxhbaugh (25) Moritz and Henriqies (26) Morits Morita Monts Morits Morita and and and and and Henrique Heumquen Henriques Henriques Henriques (26) (26) (26) (26) (26) = 0. OS Pigs Pig Piga Pigs Pigs Co™ (‘a7 sree y" ys tween that required to produce threshold skin damage and that for permanent damage in pigs ix SOU to 1000 rep (26). One is not justified * Reported cHoical experience with radiation skin lemioas is based predominantly on the response of people. wherean the jiesions described berein were observed primarily io the Marshaliene, a highly pigmented peopie, Euganr (Mavi U. 5 0.5 05 0.5 0.5 sre Pign Avanaas ps pe pe Pp» pe Nheep mals. Jt is apparent from the table that beta ray energy is of considerable importance in determining the degree of injury. According to Moritz and Henriques, the difference in dose be- whiteskinped lporors 0.3 u. Ol v2 U 3 U5 U7 Scarace Doss (agr) 1, 4, 2, 2, 5, 500-4, 000 WUO OO 500 00D eee aes ee iene blondes with light pigment are nore sensitive In comparing animal lewions from known ones ee Oe minim! dermal injury are vetable. The particulete natare and uneven distribution of the fate matenai was responsible for the spntty nature of the lestons and, the large componen: of soft energy beta radiation was responsible for the greater epitiermail injery. the pron: nenre ef pigerntary changes is probably related te rarce.® [tin generally conceded that 2. 500-5, UOO 20), UOU-30, 000 4, 2, 1, 1, 1, 000-5, 000-3, §00-2, 500-2, 500-2, ODO 000 000 000 000 doses of whole-body radiation, the defenses against infection might have been sufficiently impaired to have resulted in serious complications from skin lesions of the severity encountered. Severe radiation injury is known to predis- pose to cancer. The probability of the develop- ment of malignancies at the site of healed lesions ig unknown, Certain factors appear to dec. ase the probability: (a) The majority of the lesions were superficial, ——— and the severe, spotty epidermal injury with (b) Visible signs of chronic radiation dermatitis are absent in vey to, 3%

Select target paragraph3