Atoms can, however, lose or gain electrons due to collisions or other interactions, often with nuclear radiation. When they do, they form charged particles called ions:
Radioactive materials are hazardous. Nuclear radiation can ionise chemicals within a body, which changes the way the cells behave. It can also deposit large amounts of energy into the body, which can damage or destroy cells completely. Ultraviolet, x-rays, alpha, beta and gamma radiations are all examples of ionising radiations. Molecules in cells can be altered as well as the DNA.
Some of the effects that radiation has on a human body are shown below.
|Eyes||High doses can cause cataracts.|
|Thyroid||Radioactive iodine can build up and cause cancer, particularly during growth.|
|Lungs||Breathing in radioisotopes can damage DNA.|
|Stomach||Radioactive isotopes can sit in the stomach and irradiate for a long time.|
|Reproductive organs||High doses can cause sterility or mutations.|
|Skin||Radiation can burn skin or cause cancer.|
|Bone marrow||Radiation can cause leukaemia and other diseases of the blood.|