Which term describes the deposition of radioactive material in unintended locations?

• A. Radioactive contamination
• B. Attenuation
• C. Biologic half-life
• D. Contrast resolution

Answer: (A)

Contamination refers to radioactive material being deposited in locations where it should not be, such as on skin, clothing, surfaces, or even inside the body if it is inhaled or ingested. This concept is about where the material ends up and the potential for internal or external contamination that can spread or cause dose after deposition. Attenuation is about how radiation is weakened as it passes through matter, not where the material is deposited. Biologic half-life describes how quickly the body eliminates the substance, affecting internal dose over time. Contrast resolution is a imaging system quality related to distinguishing differences in tissue, not deposition. So the term that best fits deposition of radioactive material in unintended locations is radioactive contamination.