VPT 421: Veterinary Toxicology (2+0)

RADIOACTIVE MATERIAL

• Either natural or created in nuclear reactor or accelerator.
• Radioactive material is unstable and emits energy in order to return to a more stable state (particles or gamma-rays).

Alpha particles

• Neutrons and two protons .
• Charge of +2.
• Emitted from nucleus of radioactive atoms .
• Transfer energy in very short distances (10 cm in air).
• Shielded by paper or layer of skin.
• Primary hazard from internal exposure.
• Alpha emitters can accumulate in tissue (bone, kidney, liver, lung, spleen) causing local damage.

Beta particles

• Small electrically charged particles similar to electrons.
• Charge of -1.
• Ejected from nuclei of radioactive atoms .
• Emitted with various kinetic energies.
• Shielded by wood, body penetration 0.2 to 1.3 cm depending on energy .
• Can cause skin burns or be an internal hazard of ingested.

Gamma rays

• Electromagnetic photons or radiation (identical to x-rays except for source) .
• Emitted from nucleus of radioactive atoms –spontaneous emission .
• Emitted with kinetic energy related to radioactive source.
• Highly penetrating –extensive shielding required.
• Serious external radiation hazard.

X rays

• Overlap with gamma-rays.
• Electromagnetic photons or radiation.
• Produced from orbiting electrons or free electrons –usually machine produced.
• Produced when electrons strike a target material inside and x-ray tube.
• Emitted with various energies & wavelengths.
• Highly penetrating –extensive shielding required .
• External radiation hazard.