What are the health effects of radioactivity?
Radiation can damage the tissues in our bodies, causing burns, radiation sickness and cancer. Because of this, its use has to be carefully controlled. When people first began to work with radioactivity they did not realise that it could be harmful, and many became ill and died. Nowadays we know how to measure the dose received, and use shielding to protect ourselves and the environment from such dangers. However, this ability to damage tissue can be useful in medicine: a precisely focussed beam of radiation can be used to destroy cancer cells in tumours.
