This can cause a mutation. If the DNA in the nucleus of a cell is damaged, the cell may become cancerous. In this case the cell divides rapidly and causes serious health problems. The greater the dose of radiation a cell gets, the greater the chance that the cell will become cancerous. However, very high doses of radiation can kill the cell completely. Radioactive elements emit ionizing radiation as their atoms undergo radioactive decay. Radioactive decay is the emission of energy in the form of ionizing radiation ionizing radiation Radiation with so much energy it can knock electrons out of atoms.
The ionizing radiation that is emitted can include alpha particles alpha particles A form of particulate ionizing radiation made up of two neutrons and two protons. Alpha particles pose no direct or external radiation threat; however, they can pose a serious health threat if ingested or inhaled.
Some beta particles are capable of penetrating the skin and causing damage such as skin burns. Beta-emitters are most hazardous when they are inhaled or swallowed. Gamma rays can pass completely through the human body; as they pass through, they can cause damage to tissue and DNA. Radioactive decay occurs in unstable atoms called radionuclides. The energy of the radiation shown on the spectrum below increases from left to right as the frequency rises.
Other agencies regulate the non-ionizing radiation that is emitted by electrical devices such as radio transmitters or cell phones See: Radiation Resources Outside of EPA.
Alpha particles come from the decay of the heaviest radioactive elements, such as uranium , radium and polonium. Even though alpha particles are very energetic, they are so heavy that they use up their energy over short distances and are unable to travel very far from the atom. The health effect from exposure to alpha particles depends greatly on how a person is exposed. Alpha particles lack the energy to penetrate even the outer layer of skin, so exposure to the outside of the body is not a major concern.
Inside the body, however, they can be very harmful. If alpha-emitters are inhaled, swallowed, or get into the body through a cut, the alpha particles can damage sensitive living tissue. The way these large, heavy particles cause damage makes them more dangerous than other types of radiation. The ionizations they cause are very close together - they can release all their energy in a few cells.
This results in more severe damage to cells and DNA. These particles are emitted by certain unstable atoms such as hydrogen-3 tritium , carbon and strontium Beta particles are more penetrating than alpha particles, but are less damaging to living tissue and DNA because the ionizations they produce are more widely spaced.
They travel farther in air than alpha particles, but can be stopped by a layer of clothing or by a thin layer of a substance such as aluminum.
Most beta emitters can be detected with a survey instrument and a thin-window GM probe e. Some beta emitters, however, produce very low-energy, poorly penetrating radiation that may be difficult or impossible to detect. Examples of these difficult-to-detect beta emitters are hydrogen-3 tritium , carbon, and sulfur Clothing provides some protection against beta radiation.
Examples of some pure beta emitters: strontium, carbon, tritium, and sulfur Gamma and X Radiation Gamma radiation and x rays are highly penetrating electromagnetic radiation. Some characteristics of these radiations are: Gamma radiation or x rays are able to travel many feet in air and many inches in human tissue. They readily penetrate most materials and are sometimes called "penetrating" radiation.
X rays are like gamma rays. X rays, too, are penetrating radiation. Sealed radioactive sources and machines that emit gamma radiation and x rays respectively constitute mainly an external hazard to humans. Gamma radiation and x rays are electromagnetic radiation like visible light, radiowaves, and ultraviolet light. These electromagnetic radiations differ only in the amount of energy they have. Gamma rays and x rays are the most energetic of these.
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