Ionizing Radiation Study Guide: Alpha and Beta Particles Plus Their Effects

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Just What Is It?

Ionizing radiation is a dangerous form of electromagnetic radiation that can cause damage to the body’s tissues due to the high amount of energy that is involved. Potential sources of ionizing radiation include X-rays, ultraviolet radiation from the sun and radiation that is emitted from radioactive isotopes. Every year people are exposed to insignificant amounts of ionizing radiation due to natural sources present in human activity.

Nuclear power plants are only responsible for low levels of exposure if operated correctly. However disastrous nuclear accidents such as Chernobyl can release large amounts of radioactive material into the environment. Large scale disasters that have resulted in lost life have led many people to chide nuclear power plants, despite the relatively small health risk if they are operated correctly.

What Are the Potential Effects?

There is an array of devastating effects that can result from high levels of ionizing radiation. Ionizing radiation can easily penetrate the human cell and ionize an electron from a cellular chemical which alters the molecules that are necessary for mundane cellular function. This can result in somatic damage and genetic damage.

Genetic damage from mutations in DNA molecules can directly alter chromosomes resulting in genetic defects in later generations. Genetic damage is not seen in the victim’s life if caused by ionizing radiation; it is most often seen in the offspring of an exposed individual. Somatic damage occurs in the exposed individual’s tissue; the effect of this is seen in the victim’s life. Somatic damage is manifested in burns and numerous types of cancers.

Dose Response Curve for Ionizing Radiation

Most scientists deduce that the dose response curve for ionizing radiation is linear because harmful effects are seen even at very low exposure. However, others argue that the body is able to repair some of the damage and are in favor of a threshold level curve.

The ultimate effect of ionizing radiation varies with the type of particle. Alpha particles have more energy than beta particles; however, they lack the penetrating power that beta particles possess. Alpha particles cause more damage when they are outside of the body such as their ability to cause skin cancer. On the other hand, beta particles can penetrate the skin and cause damage to internal organs.

Limiting Exposure

By limiting the time that one is exposed to natural background radiation, the dose from the radiation source will be reduced. In addition, the intensity of radiation decreases dramatically with distance. Shielding and containing the source of radiation is also imperative. Barriers of materials such as lead and concrete provide protection from radiation that contain gamma rays and neutrons. Radioactive material is also contained in the smallest volume possible and kept away from the environment and human population. Ionizing radiation can be caused by X-rays, radiation from nuclear sources and ultraviolet radiation caused by increased sun exposure.