Effects of ionizing radiation

U.S. radiation protection guidelines are estabHshed by the National CouncH on Radiation Protection and Measurement (NCRP) and are based on the recommendations of the International Commission on Radiological Protection (ICRP). The National Research CouncH also sponsors a report from its advisory committee on the biological effects of ionizing radiations (20). 

The stabilizing of halogen resins against the adverse effects of ionizing radiation has been obtained by using an ester of glycerol and thioglycolic acid... 

N.uional Research Council, 1972, The Biological Effects of Ionizing Radiations, National Academy of Sciences. 

The theory of radiation-induced grafting has received extensive treatment. The direct effect of ionizing radiation in material is to produce active radical sites. A material s sensitivity to radiation ionization is reflected in its G value, which represents the number of radicals in a specific type (e.g., peroxy or allyl) produced in the material per 100 eV of energy absorbed. For example, the G value of poly(vinyl chloride) is 10-15, of PE is 6-8, and of polystyrene is 1.5-3. Regarding monomers, the G value of methyl methacrylate is 11.5, of acrylonitrile is 5.6, and of styrene is >0.69. 

The effects of ionizing radiation on expls and related energetic materials have been well investigated over the years (see Radiation Effects on Explosives in Vol 9) and are quite predictable. 

The chemistry, and hence hazards, of hot, or radioactive, elements parallels that of their cold isotopes. However, the radiation poses additional toxicity hazards. A qualitative classification of selected isotopes in terms of their toxicity is given in Table 10.2. The biological effects of ionizing radiation stem mainly from damage to individual cells following ionization of the water content. Oxidizing species, e.g. hydrogen peroxide. 

The bactericidal effects of ionizing radiation have been known for a century, and for over 80 years it has been known that ionizing radiation kills the Ttichinella spiralis parasite, which infects raw pork. By the mid-1970s, international experts had concluded that irradiating foods preserves them without creating any toxicological hazards. Only in the last decade, however, has preservation by irradiation been applied commercially. 

BEIRIII. 1980. The effects on populations of exposure to low levels of ionizing radiation. Committee on the Biological Effects of Ionizing Radiations, National Research Council. Washington, DC National Academy Press. 

Mettler F, Moseley R. 1985. Medical effects of ionizing radiation. New York Grune and Stratton. 

The effect of ionizing radiation on molecular or ionic solids is to eject electrons, which often subsequently react at sites in the material well removed from the residual electron-loss centre. These electron-loss and electron-gain centres, or breakdown products thereof, are paramagnetic and have been extensively studied by e.s.r. spectroscopy. Results for a wide range of organo metals both as pure compounds and as dilute solid solutions are used to illustrate this action. Aspects of the electronic structures of these centres are derived from the spectra and aspects of redox mechanisms are discussed. 

There are several groups of chapters discussing the health effects of radon and its decay products. In Pohl-Ruling et al. (1987) and Reubel et al. (1987), the direct effect of ionizing radiation on cell behavior are presented. Such studies help to elucidate the relationship between the radiation dose and the response at the... 

United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), Sources and Effects of Ionizing Radiation, UNIPUB, New York (1977). 

US-National Academy of Sciences, National Research Council BEIR-II Biological Effects of Ionizing Radiation, Washington, D.C., USA (1972). 

One of the most sensitive biological effects of ionizing radiation is to increase the frequency of normally observed chromosome aberrations (but not to induce qualitatively special abnormalities). Peripheral blood lymphocytes are the most feasible cells for chromosome investigations, as blood samples are easy to obtain and the techniques to stimulate the lymphocytes to proliferate within a culture medium and to prepare suitable chromosome slides for microscopic analyzation have their routine protocoil (e. g. Yunis, 1965 Lloyd et al, 1982). 

Pohl-Ruling, J., P. Fischer, and E. Pohl, The Low-Level Shape of Dose Response for Chromosome Aberrations, in Proceedings of the International Symposium of Late Biological Effects of Ionizing Radiation (International Atomic Energy Agency) pp. 315-326, Vienna, Austria, (1978). 

Radiation is carcinogenic. The frequency of death from cancer of the thyroid, breast, lung, esophagus, stomach, and bladder was higher in Japanese survivors of the atomic bomb than in nonexposed individuals, and carcinogenesis seems to be the primary latent effect of ionizing radiation. The minimal latent period of most cancers was <15 years and depended on an individual s age at exposure and site of cancer. The relation of radiation-induced cancers to low doses and the shape of the dose-response curve (linear or nonlinear), the existence of a threshold, and the influence of dose rate and exposure period have to be determined (Hobbs and McClellan 1986). 

Cothem, C.R., D.J. Crawford-Brown, and M.E. Wrenn. 1990. Application of environmental dose-response models to epidemiology and animal data for the effects of ionizing radiation. Environ. Inter. 16 127-140. 

International Atomic Energy Agency (IAEA). 1976. Effects of Ionizing Radiation on Aquatic Organisms and Ecosystems. Technical Reports Series No. 172. IAEA, Vienna, Austria. 131 pp. 

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