Question

What are some examples of biological effects of radiation?

Answer 1

It can damage DNA, kill cells and cause cancer.

Explanation:

Alpha, beta and gamma radiation are known as "ionising radiation". This means that they can knock electrons off neutral molecules or atoms to create ionised particles (ions).

These ions can be very unstable and react differently with other molecules. If ionising radiation penetrates cells in the body, it can ionise molecules inside the cell, which can change the way molecules in the cell react. This can damage the DNA in the cell and even kill it. Large doses of radiation can lead to:

• Radiation burns (redness and soreness on skin)
• Eye cataracts
• Cancer
• Radiation sickness and death

If a cell has its genetic information damaged but it is not killed by the radiation it can replicate and become cancerous.

One example of radiation affecting cells is sunburn: prolonged exposure to the UV radiation from the sun can cause burns, and skin cancer (melanoma) with repeated exposure.

Some radioactive isotopes are chemically similar to other vital elements, and can be taken by the body and used in place of those elements. This can be dangerous as the isotope can stay in the body for an extended period of time and cause more radiation damage to cells.

For example `""_38^90Sr` (`beta` radiation) is chemically similar to `Ca`. If it is taken in by cows it can get into the milk, which is ingested by humans. The isotope can be deposited into the bone, irradiating the bone marrow. This can kill the cells and stop the production of red and white blood cells.