What is the difference between external and internal radiation exposure?

The distinction between external and internal radiation exposure is critical in understanding how radiation interacts with the human body and the environment. The correct answer highlights that external exposure refers to radiation that originates from sources outside the body, such as radioactive materials in the environment or radiation from medical imaging devices. This type of exposure can result from various sources, including cosmic rays, terrestrial radiation, or artificial sources like X-rays.

On the other hand, internal exposure relates to radiation emitted from radioactive materials that have been ingested, inhaled, or absorbed into the body. This can occur through contaminated food, water, or air, and can include radionuclides that accumulate in specific organs or tissues, leading to potential long-term health effects.

Understanding this distinction is vital for assessing risks and implementing appropriate safety measures in environments where radiation is present. By recognizing the sources and pathways of radiation exposure—whether external or internal—radiation protection practices can be effectively tailored to minimize health risks.