Radiation and radioactivity

Harley, N. H. (1996). Toxic effects of radiation and radioactive materials. In Cdsarett and Doull s To.xicology The Basit Saettce of Poisons (C. D. Klaassen, Ed.), pp- 77 VS00. McGravi -Hill, New York. 

Figure 32.9 Survival time and associated mode of death of selected mammals after whole-body doses of gamma radiation. (Modified from Hobbs, C.H. and R.O. McClellan. 1986. Toxic effects of radiation and radioactive materials. Pages 669-705 in C.D. Klaassen, M.O. Amdur, and J. Doull [eds.]. Casarett and Doull s Toxicology. Third Edition. Macmillan, New York United Nations Scientific Committee on the Effects of Atomic Radiation [UNSCEAR]. 1988. Sources, Effects and Risks of Ionizing Radiation. United Nations, New York. 647 pp.)...

Hobbs, C.H. and R.O. McClellan. 1986. Toxic effects of radiation and radioactive materials. Pages 669-705 in C.D. Klaassen, M.O. Amdur, and J. Doull (eds.). Casarett and Doull s Toxicology. Third Edition. Macmillan, New York. 

Radiation is one area of science not well understood by the lay public, and often the media information relating to radioactivity is misleading and misunderstood. To some extent, the topics of radioactivity and radiation have become a political issue. The public is somewhat scientifically illiterate about radiation, and many people do not have a very clear understanding of the physical nature, sources, uses, benefits, and dangers of radiation and radioactivity. We can all learn more about radioactivity so that it can be used for the benefit of mankind without undue fear. After all, it is very natural and universal. Radioactivity takes place both inside and on the surface of our Earth. Not only does it exist in space, but it also is penetrating our bodies at all times from natural sources, and small amounts of radiation exist in our tissues and organs. It is part of all life. 

The therapeutic uses of radiation and radioactivity are no less important than the diagnostic uses. One is most familiar with external sources of radiation being used to destroy diseased tissue. A problem with these radiation therapies is similar to that... 

Since these classic experiments were performed, much has been learned about radiation and radioactivity, including how we can use it to benefit humankind. To many, however, radiation and radioactivity remain mysteries and even something beyond comprehension, perhaps only something to be feared. 

The terms radiation and radioactivity are often confused. Radiation refers to electromagnetic radiation— everything from gamma rays, to X-rays, to visible light, to microwaves, to radio and television signals. Radioactivity, on the other hand, involves the emission of particles or energy from an unstable nucleus. 

T, T, CE Even though radiation and radioactive substances can have negative effects on humans, if used correctly and in the right amounts, they can also be beneficial to humans as well. 

It is important to distinguish between radiation and radioactive contamination. Radiation is energy emitted by atoms that are unstable. Radiation travels through space to some extent—some kinds of radiation can only travel a few millimeters, whereas other types can travel for many meters. Radioactive contamination is the presence of radiation-emitting substances (radioactive materials or RAM) in a place where it is not desired. A patient may be contaminated with radioactive materials, but that patient will not be inherently radioactive and can be decontaminated. Radioactive materials, by comparison, are inherently radioactive—it is a physical property of that material in the same manner as mass or size—and they remain radioactive until they decay to stability. 

Both patients and medical staff are understandably concerned about the health effects of exposure to radiation and radioactive contamination. There are two distinct types of radiation exposure, acute and chronic, and two primary exposure modes, radiation and radioactive contamination. Each exposure type and mode is slightly different and must be treated differently by medical staff (see Table 27.2). In addition, there are concerns about the reproductive effects of radiation exposure. In this section, these concerns will be discussed. 

The public, emergency responders, and medical personnel often respond inappropriately to radiological incidents and emergencies, owing to widespread misunderstanding of the risks posed by radiation and radioactivity. In particular, members of the public often panic and tend to attribute all real and perceived health problems to the effects of radiation. Emergency response personnel sometimes hesitate to approach the scene of... 

Harley, N.H. (2008). Health effects of radiation and radioactive materials. In Casarett and Doull s Toxicology The Basic Science of Poisons, 7th edition (C.D. Klaassen, ed.), pp. 1053-82. McGraw-Hill Medical, New York. 

Hobbs C, McClellan R. 1986. Radiation and radioactive materials. In Doull J, et al., eds. Casarett and Doull s Toxicology. 3rded. New York, NY Macmillan Publishing Co., Inc., 497-530. 

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