how do you die from radiation exposure ?


I started watching Chernobyl and I got interested on how do people perish from exposure to radiation in general, and if you can furthermore elaborate and point out the difference when on high levels of radiation like in Chernobyl

In: Biology

The kind of radiation in question is referred to as ‘ionizing radiation’ which means that it has enough energy to penetrate into your body and start knocking electrons off of whatever atoms it happens to collide with in there.

Electrons are pretty important for atoms, because they’re one of the primary factors in determining what sorts of chemical reactions those atoms are capable of and/or likely to get involved in. Since biology is basically a giant mess of chemical reactions, it’s generally a bad thing when a bunch of the atoms in your body get changed and start reacting differently than they’re supposed to.

If you receive a really high dose of radiation in a short period of time, then enough of the atoms get messed up at once that significant parts of your biology stop working and even start to fall apart. And so you can die pretty quickly.

If it’s lower levels of radiation, the damage is less, and your body can repair a decent amount of it. But there’s still the problem of some of that damage occurring to your DNA. Most of the cells in your body contain DNA, which is sort of like the blueprint that your body uses to build and repair and maintain itself over time. Most of the cells in your body have a limited lifetime, and are replaced fairly often over the course of your overall life. But if the radiation damages that blueprint, then your body is now trying to repair itself with faulty instructions, and over time that can lead to compounding health problems.

For lower levels of radiation this usually means you’ve got higher odds for cancer. For higher levels, this could mean that your body is replacing dead cells with defective ones, and eventually there’s enough defective cells that you start seeing things like organ failure.

So the details of how you die from it really depends on how much radiation you take in, but in all cases it’s due to the energetic particles of the radiation entering your body and messing things up at a molecular/atomic level.

Three possible ways:

One is that the radiation can cause cellular mutations that lead to cancer. This is the most common and is usually caused by long term exposure to smaller levels of radiation. Similarly the cells may die or cease to replicate, eventually dying out; this is what causes hairloss for example.

The other is that radiation can shut down your immune system, rendering you vulnerable to things that would not normally pose a threat to a person with a functioning immune system. This is similar to what happens to people who suffer from AIDS or are using radiation therapy for cancers. This is usually caused by short exposure to extreme levels of radiation.

Another rarer instance is that radiation can produce massive heat, such as in the case of [the elephant’s foot](

When things are “radioactive” it basically means they are unstable and break down over time. When they break down, they release tiny (atomic level) particles that shoot off into the surrounding area and slam into whatever is in their path. If that thing in its path is your body, its like your DNA is being shot by a bunch of pellet guns. Over time your DNA becomes too damaged and you start making a bunch of mutant cells that don’t work properly.

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