Dangers

There was a time when ladies could buy skin cream which contained small amounts of radioisotopes. The skin would feel warm and have a lovely pink look. It worked by actually killing the skin cells, just like if you were burned. Many women died too because of skin cancer.

Nuclear radiation is dangerous. It is dangerous because it damages the molecules in our cells so that they don't work properly. The cell may die. If you are exposed to a lot of radiation then a lot of cells may be killed and you would be very ill.

The molecules are damaged because atoms which make up the molecule are ionised. This means that when the radiation bashes into them it knocks off electrons from the outside of the atom. They become ions. One alpha or beta particle has enough energy to cause thousands of ionisations.

You might think that alpha was the least dangerous because it can't even get through paper. When handled carefully it is safe. It is most dangerous when it comes in contact with the skin or gets inside the body.

Cancer

What would happen if nobody died? Imagine also that the people alive kept having children. What would happen to the planet?

Most of the cells in our body are only supposed to last for a certain time. A months or a few years at the most. Their life cycle is controlled by genes in the nucleus of the cell. Sometimes these genes don't work properly and the cells multiply rapidly and don't die. This is what cancer is. It is very hard to fight cancer because it our own body cells which are the problem so our immune system doesn't recognise them as a threat.

Cancer may be caused by a number of things. Some people inherit faulty genes off their parents which increase the chances of them getting cancer at some time in their life. Some chemicals can cause cancer. There are lots of these in cigarette smoke. Ionising radiation can cause cancer if it damages the molecules in our genes. The more radiation you are exposed to the greater the risk of cancer.