This document provides an overview of radioactive pollution including: - Definitions of radioactive contamination and ionizing radiation. - Natural sources include radioactive minerals, cosmic rays, and naturally occurring radioisotopes. Anthropogenic sources are nuclear tests, reactors, medical applications, and waste. - Effects on humans can range from mild irritation to cancer, depending on exposure level and duration. Rapidly dividing cells are most at risk. - Prevention methods include limiting nuclear activities, careful disposal, and using shielding and ventilation in high exposure areas. The document concludes by calling for reduced nuclear power usage going forward.