4.4.3.3 - Uses of nuclear radiation

Describe the risks associated with using radiation.

Radiation can enter living cells and ionise atoms and molecules within them - leading to tissue damage

Lower doses of radiation can cause minor damage, which can give rise to mutant cells which divide uncontrollably - cancer

High doses kill cells completely - causing radiation sickness

What are some of symptoms of radiation sickness?

• Vomiting

• tiredness

• hair loss

What are the uses of radiation in medicine?

• Control or destructive of unwanted tissue

• Exploration of internal organs

What is used to explore internal organs?

Gamma rays are used in medical tracers

How do medical tracers work?

Medical tracers work through the injection of a certain radioactive isotope into the people

The isotopes progress around the body can then be followed using an external detector

Give an example of an isotope used to test thyroid function.

Iodine -23

Which is absorbed by the thyroid gland

Describe how iodine -23 is used as a medical tracer.

This iodine isotope gives our radiation that can be detected (outside the body by an external detector)

This can then indicate whether the thyroid gland is taking in Iodine as it should be

What type of radiation do the isotopes in medical tracers usually give off?

These isotopes are usually :

• gamma

• have short half-lives

Why are these specific types of isotopes used in medical tracers?

Gamma - means the radiation is able to pass out the body without causing much ionisation

Short half-life - so the radioactivity of the isotope dies out quickly and becomes safe (minimising damage)

What is an example of using radiation to control or destroy unwanted tissue?

Radiotherapy

What is radiotherapy?

Radiotherapy refers to the treating of caner with radiation

Describe how radiotherapy is used to treat cancer.

Since high does of ionising radiation can kill all living cells.

Gamma rays can be directed carefully to kill the cancer cells (without damaging too many normal cells)

Or , Radiation emitting implants can be put next to or inside tumours

What radiation do radiation emitting implants usually emit?

Using beta emitters

What is one con of radiotherapy?

Some damage is inevitably done to normal cells which makes the patient feel ill

What is perceived risk?

Perceived risk refers to how risky a person thinks something is

Can vary from person to person

Is perceived risk the same thing as the actual risk?

No - perceived risk is not the same as actual risk and can vary from person to person

Give the perceived risk of medical tracers.

Medical tracers can be used to diagnose life-threatening conditions

But these tracers also have a very small risk of cancer

Give the perceived risk of radiotherapy.

Prolonged exposure to radiation can pose future risks and cause many side effects

But people with cancer still choose to use it as it may get rid of their cancer entirely