-
Asked by anon-290828 on 28 Mar 2021.
Question: my question is aboat radiation (the kind that exploaded in chernobly npp pripyat) i am quiet interested in it and i would like to know more maily about how it functions and what it does to slowly kill and mutate objects? could it be used for good on only bad (as we see it)? and would there be somthing on the planet that would be able to kill it like a tree absorbs co2 and turns it it to o2?
-
Chris Waller answered on 19 Mar 2021:
The Chernobyl disaster occurred in 1986 and the effects are still being felt to this day. A lot of things went wrong that day but the end result was that large amount of radioactive material was scattered over a large area, contaminating it for a very long time.
~
Radiation, in particular ionising radiation, is dangerous because it has the ability to “ionise” atoms. This means it can break chemical bonds. This is dangerous to humans because it can destroy the biomolecules that keep us alive such as proteins and DNA. High levels of radiation can kill very quickly as it can destroy these proteins meaning your body cannot function. Low levels of radiation can still cause damage, but your body is able to repair some of it so the effects are not immediate. The damage to your DNA is permanent however, and over time the “mutations” to your DNA add up to the point where proteins are no longer made correctly, which can lead to diseases such as cancer.
~
Every radioactive element has a property known as a “half-life”, which is the time needed for 50% of the material to decay. If you safely contain the material (eg. bury it in a big hole deep underground) and wait it will eventually become safe. The problem is that this takes a VERY long time – for example the half life of uranium-235 is over 700 million years! That means it will take BILLIONS of years to become safe. The best way to clean up a disaster such as Chernobyl is to never let it happen in the first place.
~
Whilst radiation is mostly bad, there are some useful aspects of it. For example, it gets used a lot in medicine to take “x-ray” images or treat cancer using “radiotherapy”. We can use it to tell the age of very old things using “radiocarbon dating”. It is used extensively in industry to sterilise food, killing bacteria that would otherwise make us sick. And of course we can use it to create electricity in “nuclear power plants”. Nuclear energy in fact is actually one of the safest forms of power generation in the world – hundreds of times safer than alternatives such as coal or other fossil fuels.
-
-
Callum Thomas answered on 19 Mar 2021:
Hi Aidan. Thanks for the question. I am not a physicist so I can’t exactly answer fully the question about how radiation is produced, but I can tell you about its effects on living organisms. Basically the reactions that happen in a nuclear power plant or nuclear explosion involve splitting an atom which releases a lot of energy as well as a bunch of very small particles and electromagnetic waves. Some of these waves and particles have lots of energy and move extremely fast. This energy can break apart the bonds that hold the molecules that make up our bodies together. If this energy only reaches the outside of the body, it might damage the molecules and proteins in the skin, causing burns in the same way heat radiation from a fire can cause burns. As you can imagine this can be very dangerous, especially if particles are swallowed or breathed in and damage the lungs or stomach. However some of the waves and particles have so much energy they can actually penetrate solid objects, including the bodies of living organisms, like x-rays or gamma rays. This can damage the DNA molecules inside the cell. Since DNA contains all the instructions that tell the cells of the body what to do, this can have very serious effects. If just a few breaks happen the body can repair these, however if too much DNA is damaged the cell will die.
—
If the level of radiation is lower, it might not destroy all the DNA and kill the cell but instead it can cause mutations to occur. A mutation is just a change to the DNA sequence of an organism. This can happen because the body’s DNA-repair mechanism is not perfect and sometimes makes mistakes. So if the body has to repair lots of breaks in DNA caused by radiation, changes might occur after the DNA is repaired. If a part of the DNA that tells the cell when to stop growing is changed, the cell might keep growing and multiplying without any control, which is what we call cancer. Similarly if the DNA controlling the development of a baby is changed within the sperm or eggs of a person, any children that person has may have a chance of being born with some kind of birth defect.
—
To answer your question about whether radiation can be used for good, the answer is yes! Apart from producing energy in nuclear plants, penetrating rays like x-rays can be very useful in medicine to let us see inside the body. They also aren’t that dangerous if you are only rarely exposed to them for a very short time (although if you ever get an x-ray you will notice the doctor or nurse will leave the room as it’s better they are not exposed every time they see a different patient). Similarly, penetrating radiation can also be used to try and kill cancer cells by firing it in a very controlled and directed fashion at the cancer within the body.
—
To answer your last question about “killing” radiation, it is hard to remove radiation once it has been released. Particles released from a nuclear explosion can hang around and give off energy for a long time. However some kinds of radiation can be blocked by some very dense and heavy materials like lead or very thick concrete that it cannot penetrate. So generally in cases like Chernobyl or other nuclear accidents, the main method is to simply remove and bury all contaminated materials under a layer of soil or concrete thick enough to block radiation from penetrating out into the environment.
Comments