What is internal contamination, and how can it occur?

Internal contamination refers to the presence of radioactive substances within the body, which occurs primarily through ingestion or inhalation of radioactive materials. When these materials enter the body, they can accumulate in various organs and tissues, potentially resulting in harmful effects due to radiation exposure from within.

The process can happen in several ways: inhalation of radioactive dust or aerosols, ingestion of contaminated food or water, or absorption through wounds. Once inside the body, these radioactive materials can continue to emit radiation, which poses health risks and can lead to conditions such as radiation sickness or increased cancer risk over time.

The other options, while related to radiation safety, describe different scenarios. Skin exposure pertains to external contamination and does not involve the internal effects of radioactive materials. External exposure to contaminated surfaces involve risk from radiation outside the body without internal absorption. Electrical interference, while a concern in radiation detection, does not relate to contamination at all. Thus, internal contamination specifically highlights the concern of radioactive materials entering the human body and the subsequent health implications.