6!

• What is irradiation?


  Exposing objects to beams of radiation is called irradiation
• What is the gamma knife?


  can be used to kill cancerous tumours deep inside the body. The beams are aimed at the tumour from many different directions to maximise the dose on the tumour but to minimise the dose on the surrounding soft tissue. This technique can damage healthy tissue, so careful calculations are done to establish the best dose - enough to kill the tumour but not so much so that the healthy tissue is damaged
• What is irradiation used for?


  Used for:

  • Sterilizing medical equipment
  • The Gamme knife
  • Preserving fruit
• Does contamination cause the object to become radioactive?

  NO
• WHAT ARE THE DISAVANATGES of irradiation?


  It may not kill all the bacteria on an object

  It can be harmful - being in an environment where objects are being treated by irradiation could expose people’s cells to damage and mutation
• What are the advantages of irradiation?


  Sterilisation can be done without high temperatures

  It can be used to kill bacteria on things that would melt
• How can contamination be used?

  • Radioactive sources can be used as tracers to make soft tissues show up through medical imaging processes. An isotope emits gamma rays that can be detected outside the body. Changes in the amount of gamma emitted from different parts would indicate how well the isotopes are flowing or if there is a blockage, possibly caused by cancer
  • Treating cancer by injecting tumours with the radioactive material - the cancer cells absorb radiation from the material and receive a high dose of energy
• What are the disadvantages of contamination?

  Radioactive isotopes may not go where they are wanted

  It can be difficult to ensure that the contamination is fully removed so small amounts of radioisotope may still be left behind

  Exposure to radioactive materials can potentially damage healthy cells