uses and dangers of radioactivity Flashcards
What is radiation?
Energy carried by particles form a radioactive substance of spreading out for a source.
What is irradiation?
It is when you expose an object to a source of radiation. For example you can expose fruit to gamma rays in order to destroy bacteria. This is said to have been irradiated.
What is radioactive decay?
The process in which an unstable nuclei break apart or change, releasing radiation as they do so.
What can irradiation be used for?
Sterilisation of fruits using gamma rays to preserve them by killing bacteria.
Medical irradiation-
They can use irradiation to sterilise surgical instruments.
Beams of gamma rays called a gamma knife can be used to kill cancerous tumours deep inside the body.
What are the advantages of irradiation?
Sterilisation can be done without high temperatures
It can be used to kill bacteria on things that would Melt
What are the disadvantages of irradiation?
It may not kill all bacteria on an object
It can be very harmful
What is contamination?
It is when an object has a radioactive material introduced into it. This is not when its irradiated but rather when its injected.
What are advantages of contamination?
Radioactive isotopes can be used as medical and industrial tracers.
Exposure can be limited when you use isotopes with a short half life.
Imaging processes can replace invasive surgical procedures.
Disadvantages of contamination?
Radioactive isotopes may not go where they are wanted.
It is hard to ensure contamination is fully removed.
Exposure to radicalise materials van potentially damage healthy cells.
What rate some of the main differences between Irradiation and contamination?
Irradiation Occurs when an object is exposed to a source of radiation outside the object
Occurs if the radioactive source is on or in the object
Doesn’t cause the object to become radioactive
A contaminated object will be radioactive for as long as the source is on or in it
Can be blocked with suitable shielding
Once an object is contaminated, the radiation cannot be blocked
Stops as soon as the source is removedIt
can be very difficult to remove all of the contamination
What are the effects of radiation on the body e.g eye, thyroid, lungs, skin, bone marrow, reproductive organs.
Eye- van cause cataracts
Thyroid-radioactive iodine can build up and cause cancer
Lungs- breathing in radioactive isotopes can damage DNA
Skin-can burn skin or cause cancer
Reproductive organs-can cause sterility or mutations
Bone marrow-can cause leukaemia and other blood diseases
Which type of radiation is used in a household smoke alarm?
Alpha
