Alpha energy cell damaging effectiveness

An alpha particle, with a mass equal to 7,300 times that of an elecfron, loses its energy over a relatively short distance. Since 33.85 eV is required to produce an electron pair, an alpha particle (t5q)ically 5 MeV of energy) can produce approximately 7,400 electron pairs within 1 micron (pm) of tire decay. Penefration by alpha particles can easily be stopped by a sheef of paper (100 pm thick) or the protective (dead) layers of sl. Most damage caused by alpha particles occurs when they are ingested or inhaled because they end up in close proximity to living cells. The effects of ingested or inhaled alpha particles will be discussed in greater detail later in this chapter. 

Similar commercial radiation instruments are available, including those sensitive enough to detect alpha radiation. Health effects of exposure to radiation can vary (see Figure 9.9). Nonionizing radiation comes from ultraviolet and infrared energy waves. This type of radiation causes a sunburn type of injury. This is not a major concern for hazardous materials responders. Ionization damage occurs at the cellular level. Four types of short-term effects on the cells can occur ... 

As we discussed in Section 19.2, the energy associated with radioactivity can ionize molecules. When radiation ionizes important molecules in living cells, problems can develop. The ingestion of radioactive materials—especially alpha and beta emitters—is particularly dangerous because the radioactivity once inside the body can do even more damage. The effects of radiation can be divided into three different types acute radiation damage, increased cancer risk, and genetic effects. 

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