You are here : Home > Health effects > From exposure to toxic effects


From exposure to toxic effects

External irradiation and internal contamination

Several types of exposure to radioactive compounds exist. A distinction is made between radioactive contamination and exposure to ionizing radiation.

Published on 18 March 2015

Irradiation corresponds to the exposure of an individual to a radioactive source situated outside of the body. The body absorbs either all or part of the energy of the ionizing radiation emitted by this source. This exposure is dependent on the type of radiation, the distance between the source and the person, the duration of exposure, and the protective shields. It will stop as soon as one leaves the radiation field.

In contrast, internal contamination corresponds to the penetration of radioactive material by incorporation into the body. This can occur by ingestion, inhalation, diffusion through the skin, or directly by absorption through a contaminated wound.

Depositing of a radioactive compound on someone’s skin or hair is called external contamination.

Schematic view of differences between irradiation and contamination