When people talk about harmful radiation or radiation poisoning, it usually conjures up images of deformed animals with two heads or a glowing green lump of metal.
But biologically speaking, what exactly is “radiation” and what does it do to our cells?
Well – let’s first think about one of the most dangerous nuclear disasters in the world’s history: the terrifying wall of water that crashed into Japan on the 3rd November 2011 and shocked the world.
An earthquake off the Pacific coast of Tōhoku had a whopping great magnitude of around 9.1 – to put this into perspective, the 2010 Haiti earthquake which claimed over 100,000 lives had a magnitude of 7. As a result of the 15 meter waves crashing into Japan’s east cost, three nuclear reactors went into meltdown at the Fukushima power plant, causing one of the largest releases of radiation in history.
I’m sure you’re all aware that a ton of radiation is not a great thing for the human body – hence why an estimated 97,000 locals have been barred from returning to the region and an exclusion zone of 20 km has been set up around the power plant. But what does this high dose realistically mean for your body?
Nuclear, or ionising, radiation can be thought of as a kid that’s just downed five cans of red bull and eaten a bag of sugar – and our DNA in this instance is the proverbial china shop. Unlike radiation from a light bulb or microwave, ionising radiation can knock off electrons from molecules willy nilly, which is bad news for the two metres of DNA coiled up in every cell in our body. The radiation is energetic enough to break bonds between atoms, or create highly reactive “free radicals” which can disrupt bonds in surrounding molecules. Effectively, you get a little energy packet bouncing around in your cells, causing quite a lot of damage.
The worse case scenario for a cell is radiation-induced death, which causes the immediate effects of radiation poisoning like nausea, swelling and hair loss. If you’re exposed to enough, your blood vessels burst and your immune system is killed off, leading to a much greater chance of infection.
Cells which are less severely damaged can still accrue harmful mutations – and not the cool “hey look my eyes are lasers” X-men kind. Mutations can disrupt the control mechanisms of cell division, causing a cell to replicate uncontrollably and become cancerous. This is, unfortunately, why infants in the most affected areas have a much higher risk of developing cancer when they grow up.
But Anna, I hear you cry, if ionising radiation is so terrible, what about the people who worked at the power plant normally – surely they’ve royally screwed themselves? Well, our body is actually kind of used to a certain amount of radiation – mostly from the sun, which constantly emits DNA-damaging ultra violet radiation. Handily, we have evolved enzymes (molecules which speed up chemical reactions) that can repair this damage as fast it can happen, keeping our risk of cancer mercifully pretty low.
But spend just one hour in radiation-soaked Fukushima, and you could exceed the lethal dose. So – how can you protect against ionising radiation?
Effectively, you either need to have inherited DNA repair enzymes from your parents that are in tip-top shape and can cope with a huge load of DNA damage, or (more realistically) you need to limit the radiation your body comes into contact with.
One of the most recommended things you can do is to pre-dose yourself with iodine pills. This is because the radioactive form of iodine is quickly absorbed by a gland in your neck called the thyroid. By taking normal iodine, it prevents the absorption of the radioactive form, which instead passes through you.
But in reality, the best advice I can give you is to get as far away as possible, as quickly as possible. If that’s not possible, barriers of lead, concrete, or water can absorb radiation, and are probably your safest bet.