What Causes Contamination versus Exposure

Key points

  • People can become contaminated with radioactive materials when the materials get on their clothes, hair, or skin.
  • People can also become contaminated if radioactive materials enter their body through swallowing, breathing, or open wounds.
  • People can spread contamination to others and should take steps to decontaminate themselves.
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What causes it

Radioactive contamination and radiation exposure could occur as the result of an accident, an event in nature, or an act of terrorism. Such a release could expose people and contaminate their surroundings and personal property.

Radiation exposure

An X-ray of the lungs.
When a person has an X-ray, he or she is exposed to radiation but not contaminated.

Radioactive materials give off a form of energy that travels in waves or particles. This energy is called radiation.

When a person is exposed to radiation, the energy enters the body. For example, when a person has an X-ray, he or she is exposed to radiation.

Radioactive contamination

Radiation can affect people, plants, and animals.
A contaminated person has radioactive materials on or inside their body.

Radioactive contamination occurs when radioactive material is deposited on or in an object or a person. A contaminated person has radioactive materials on or inside their body. Radioactive materials released into the environment can cause contamination of:

  • Air
  • Water
  • Surfaces
  • Plants and soil
  • Buildings
  • People
  • Animals

External contamination

Radiation on the head and clothes.
External contamination is when radioactive material is on a person’s skin, hair, or clothing.

External contamination occurs when radioactive material, in the form of dust, powder, or liquid, comes into contact with:

  • Skin
  • Hair
  • Clothing

In other words, the contact with radioactive material is outside your body. If you are externally contaminated, you can become internally contaminated if radioactive material gets into your body.

Internal contamination

Radioactive material in different parts of the body.
Some types of radioactive materials stay in the body.

Internal contamination occurs when you swallow or breathe in radioactive materials. It also happens when radioactive materials enter the body through an open wound or are absorbed through the skin.

Some types of radioactive materials stay in the body and accumulate in different body organs. Other types are eliminated from the body in:

  • Blood
  • Sweat
  • Urine
  • Feces

How contamination spreads

If you are externally contaminated with radioactive material, you can contaminate other people or surfaces that you touch. For example, if you have radioactive dust on your clothing, you may spread the radioactive dust when you sit in chairs or hug other people.

If you are internally contaminated, you can expose people near you to radiation from the radioactive material inside your body. Body fluids (blood, sweat, urine) can contain radioactive materials if you are contaminated. Touching these body fluids can result in contamination or exposure.

Contamination at home

If you are externally contaminated, you can spread the contamination by

  • Touching surfaces
  • Sitting in a chair
  • Walking through a house

Contaminants can easily fall from clothing and contaminate other surfaces.

Homes can also become contaminated with radioactive materials from body fluids of people with internal contamination.

Making sure that others do not come in contact with dust or body fluids from a person with contamination will help prevent contamination of other people in the home.

Prevention methods

Because radiation cannot be seen, smelled, felt, or tasted, people at the site of an incident will not know whether radioactive materials were involved. You can take the following steps to limit your contamination:

  1. Get out of the current area quickly. Go inside to the closest safe building or to an area to which you are directed by law enforcement or health officials.
  2. Remove the outer layer of your clothing. If radioactive material is on your clothes, getting it away from you will reduce the external contamination and decrease the risk of internal contamination. It will also reduce the length of time that you are exposed to radiation.
  3. If possible, place the clothing in a plastic bag or leave it in an out-of-the-way area, such as the corner of a room. Keep people away from it to reduce their exposure to radiation. Keep cuts and abrasions covered when handling contaminated items to avoid getting radioactive material in them.
  4. Wash all of the exposed parts of your body using lots of soap and lukewarm water to remove contamination. This process is called decontamination. Try to avoid spreading contamination to parts of the body that may not be contaminated, such as areas that were clothed.
  5. After authorities determine that internal contamination may have occurred, you may be able to take medication to reduce the radioactive material in your body. There are some medications that can help remove internal contamination from certain radioactive materials.