Dangers of Radiation (SQA National 5 Physics): Revision Note

Dangers of radiation

• Ionising nuclear radiation can damage living things such as human cells and tissues at high doses:

• This can include:

  • Cell death

  • Mutations

  • Cancer

• If the atoms that make up a DNA strand are ionised, then the DNA strand can be damaged

• If the DNA is damaged, then the cell may die, or the DNA may be mutated when it is replicated

• If a mutated cell replicates itself then a tumour may develop

  • This is an example of cancer, which is a significant danger of radiation exposure

Radiation ionising DNA

• Acute radiation exposure can have other serious symptoms:

  • It can cause skin burns, similar to severe sunburn

  • Radiation can reduce the amount of white blood cells in the body, making a person more susceptible to infections by lowering their immune system

  • At very high doses, radiation exposure can kill cells completely, leading to severe illness or death

• The severity of the harm caused by radiation exposure is dependent on:

  • the dose

  • the type of radiation

  • the type of tissue exposed

• Because of this, it is very important to handle radioactive sources carefully

 A sign indicating the dangers of radioactivity

Safety precautions

• Safety precautions for all ionising radiation include:

  • reducing exposure time

  • increasing the distance between the source and living tissue

  • using shielding to absorb radiation