Gamma rays

Gamma rays can damage living cells. This makes them useful for destroying harmful microorganisms and cancer cells, but exposure can also harm healthy cells.

Sterilisation with gamma rays

Gamma radiation is used to sterilise food and medical equipment. It damages or destroys microorganisms, such as bacteria, reducing the risk of infection or food spoilage. The treated food or equipment does not become radioactive simply because it has been exposed to gamma radiation.

Gamma rays in medicine

Gamma radiation can help doctors locate cancer. A small amount of a radioactive substance is introduced into the body, and a detector outside the body detects the gamma radiation it emits. Some substances collect more in certain cancerous tissues, so the detected radiation can help identify where a tumour may be.

Gamma radiation can also be directed at a tumour as a treatment. It damages the cancer cells, including their DNA, so the cells may die or be unable to continue dividing.

Risks of gamma radiation

Gamma radiation can also damage healthy cells. Excessive exposure may kill these cells or damage their DNA, causing mutations. Some mutations can lead to cancer, so exposure must be carefully controlled, including during treatment.