Radiation Radiation : The process of emitting energy in the form of waves or particles. Where does radiation come from? Radiation is generally produced when particles interact or decay. A large contribution of the radiation on earth is from the sun (solar) or from radioactive isotopes of the elements (terrestrial). Radiation is going through you at this very moment! http://www.atral.com/U238.html
Ionising radiation can kill or change the nature of living cells.
The effects of the damage inflicted by the ionising radiation may:
be severe and cause immediate effects, or
not become apparent for a long time.
The biological effect of radiation depends on:
The type of radiation.
The type of body tissue or body organ that absorbs the radiation.
The total amount of energy absorbed.
The Effects of Ionising Radiation
During the Second World War, two atomic bombs were dropped on Hiroshima and Nagasaki in Japan. Those people who survived the blast were exposed to a large dose of radiation. Such doses caused severe damage to cells all over the body, especially in the skin, blood, bone tissue and gut. WW2 – Hiroshima and Nagasaki Fat Man
Many of these people died within a few weeks. Those people who were exposed to a smaller dose recovered from such immediate effects. WW2 – Hiroshima and Nagasaki
A cloud of material from the accident reached the UK and, with heavy rain, there was material deposited on parts of North Wales, Cumbria and Scotland. This caused certain farm animals (e.g. lambs) to be banned from sale as they had absorbed radiation from the grass.
(View Chernobyl: You Tube)
Chernobyl Nuclear Power Station
These effects take longer to become apparent and can be caused by much lower levels of radiation. One of the most important long-term effects of radiation is that of cancer in various parts of the body. Long term effects of Ionising Radiation
Uranium miners tended to get lung cancer due to breathing in gases which emitted alpha particles. People who painted the dials of clocks with luminous paint developed oral cancer from using their lips to make points on the brushes. Long term effects of Ionising Radiation
Exposure to ionising radiation causes cancer ? The mechanisms for cancer occurring are poorly understood at the moment. One theory is that the ionising radiation affects the DNA material within us – our genetic make-up. Our DNA contains instructions which control the cells. If ionising radiation alters these instructions in the DNA, there is a chance that cancer will develop. Genetic damage can be caused to cells by radiation, including cells which are involved in reproduction.
For example, if an element has a half life of 4 days and starts off with 16g of unstable particles, then after the first four days, 8g will remain. After the next four days, 4g will remain. After four more days, 2g will remain etc. This can be shown using a graph.