EFFECTS OF IONIZING RADIATION @ —— Rasw-E.ewent | | RurlLes Ramaresn ASTvOsneS | Faecnes Rasceree Cornea ~ —_ ~ -_-— - —- J ee Mie | ae tnsermee PY ieee ey ee EY ten !/ a ee r= Rue™ Re yo fe= Lae Cem Pre Cem - _ # @# |: | 46 1| © re &® | 33 8% || aezle | %% >100 | as | Ay i a7, 42 eo | as | ae s | | rr 20 4 I | a2 Oa,7 | 60 , 128 , ~~ a ( @ | 5.7 &4& ' 2 138 A> | &y @0 &3 17 | B75 | ag >SB ) aeste* al 35 17 > 100 3o 500 ! 015 2 L2xie*) a} 21 10° @ 10 2 1.35 10° fh 4 Hamihon, J. G. Rev. Mod. Phynées, 20: 718, 1948. ? Handbous 52, U. 8. Dept. of Commereer, National Bureau of Mandards. general, long radiological and biological halflives and produce high-energy beta particles. Thes, they cause yreater damage to bone and to the radiowensitive bone marrow than to other tissnex. The damage tothe blood forming tissue results in a reduction of blood cells, and thus affects the entire body. Information on the biological effects of in- atudiedt in animals by Hamilton (1). .\brame hhimited studies of accidental radioisotopic poisoning in humans, of from animal experimentation. “The best documented data on the effects of small amounts of internally deposited emittersin homan betngs are obtained fron studies of radium poisoning. As a result of radium . deposition, terminal anemia, bone necrosis and osteogenic sarcoma appeared after a number of years. The residual activite in the body associated with these effect-4. 1 to 2 micrograms a nuclear device. For example, no internal contamination was detected in individuals exposed to the air burst at Nagasaki and Hiroshima, In Held texts of the contaminating type of atowne detonation, animals that inhaled fission ternalls deposited isntopes is derived from the of radium. Radium is a particularly hazardous element when depouted internally because of ts Jong biological and radiological half-life. Very few data are available on the long term biological effects in human beings of the shorter lived immMopes such as Se? ['") P™ and Na*. The metabolisn, excretion and biological effects of a number of fission products have been (2), Bloom(33). However, most of these studies do nat cover the problem of the long term effects in animals produced by small amounts of in- ternally deposited isotopes. Few «lata are available concerning the effects of internal contamination with mixed fission products from naclear detonations, Contami- nation is not produced by every detonation of products during short periods of exposure were found to have insignificant amounts of internal contamination. The long termeffects (primarily malignant changes) resulting from radium deposition have been used to set the limits for maximum permussible bady concentrations of a few bone seeirIng racdhoisetopes in the body (5). Maximum permissible body content of other radioisotopes are estimated on quantities resulting in a cose of O43 rem per week to the tissue of highest CONnCENT rattan.

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