Radioactive material can enter the body by four methods.

• Inhalation—Gaseous or airborne particles, dust particulates, and matter with radioactive material may enter the body through the lungs.
• Ingestion—Internal radioactive contamination may enter the body through the gastrointestinal tract by way of contaminated food, drink, and swallowing contaminated mucous from the nasal area.
• Absorption—Radioactive material may be absorbed through the skin or mucous membranes.

Puncture or injection—Radioactive material can penetrate the body through cuts, wounds, and punctures in the skin.