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  • Radiation sickness might sound like something

  • out of a post-apocalyptic horror film.

  • And it often is.

  • It's been portrayed in movies and television for more than 50 years.

  • And those portrayals vary a lot.

  • I mean, the fate-worse-than-death described

  • in 1959's On the Beach is very different

  • than the 'based on a true story' version

  • depicted in the 2019 miniseries Chernobyl.

  • But if there's one thing pretty much all

  • these portrayals have in common, it's that

  • they get radiation sickness wrongat least somewhat.

  • Like, people don't just start oozing blood

  • out of their legs, and you can't get the

  • illness from hugging a hospitalized loved one.

  • To start off, technically, radiation sickness

  • is called Acute Radiation Syndrome or ARS.

  • And it's not one thing, but rather, a bunch

  • of different syndromes that result from being

  • exposed to large doses of ionizing radiation.

  • That's the kind of radiation that carries

  • enough energy to knock electrons off of atoms.

  • And it's a problem for your cells,

  • because all that energy can break chemical bonds and

  • therefore mess with essential molecules like DNA.

  • Your cells have ways of fixing broken molecules,

  • of course, especially breaks to DNA.

  • But they aren't perfect, so ionizing radiation

  • often leads to mutations.

  • And let's be clear: cells don't become better from these mutations.

  • The more radiation-induced mutations

  • a cell has, the more likely it is that it will die or become cancerous.

  • So although radiation can change your DNA,

  • it isn't going to turn you into a walking,

  • roaring, city destroyer a la Godzilla,

  • or give you superpowers.

  • I'd hope that radiation myth was pretty

  • obvious, but not all of them are so easy to spot.

  • For example, let's say a person walks into

  • the exact wrong room and is exposed to a lot of radiation.

  • And by a lot, I mean enough that this person

  • gets more than 0.7 grays of radiation exposure

  • from spending five minutes in that room.

  • A gray is a measure of how much energy is absorbed

  • by an object or person per kilogram of weight.

  • And though it might not sound like much,

  • 0.7 grays is a lot.

  • For comparison, when you get a chest x-ray,

  • you absorb about 0.0001 grays, and a full-on

  • CT scan exposes you to just 0.01 grays.

  • So, yeah, 0.7 grays is a lot of radiation,

  • and this person has just been exposed to it.

  • What happens next?

  • Based on Hollywood, you might think their

  • skin will instantly blister or they'll start

  • bleeding from everywhere.

  • But that's not how radiation sickness works.

  • They might have no symptoms for a while.

  • Depending on the exposure, it could take minutes

  • to hours before they enter what's called

  • the prodromal stage of ARS.

  • At this point, they might feel nauseous or vomit,

  • or have a fever, headache, or diarrhea.

  • Symptoms like these can happen on and off for a few days.

  • And we're not entirely sure why that happens.

  • The best explanation we have is that radiation

  • somehow activates cells in the gastrointestinal

  • tract to release the neurotransmitter serotonin,

  • and that triggers the brain's vomit center.

  • A similar thing can happen when people get chemotherapy.

  • What's weird about ARS, though, is that

  • after this period of queasiness, people often feel a lot better.

  • This is what's known as the latent stage.

  • And as the name implies, during this phase,

  • it might not seem like there's a lot going on.

  • A person who's been exposed can feel generally

  • healthybut they're not.

  • Oddly enough, this is the stage where cells are actually dying.

  • You see, the cells that die from radiation

  • generally don't die right away.

  • DNA damage mostly becomes a problem when cells

  • go to divide and realize they can't, because

  • the DNA has breaks in it or

  • the coding sequence is wrong.

  • So the length of the latent period

  • partially depends on where the

  • radiation damage occurred

  • and how often the affected cells divide.

  • That's why, when symptoms start to show

  • up, they often appear in places like the intestines,

  • bone marrow, or skin, because those tissues

  • contain cells that divide the most often.

  • Of course, how long the latent period lasts also depends

  • how strong the dose of radiation was.

  • Higher doses over a shorter period of time

  • mean more damage, faster.

  • Now, the latent period might sound similar

  • to the incubation period of other illnesses

  • where a person doesn't show symptoms,

  • but they can transmit the disease to someone else.

  • But, unlike TV shows would have you think,

  • people with ARS aren't dangerously radioactive.

  • Their radiation sickness isn't contagious.

  • You could, say, sit by the bedside of your

  • dying partner for days or even weeks, and

  • you wouldn't develop ARS yourself.

  • Now, it is possible for a person to be emitting

  • dangerous amounts of radiation right after

  • they've left the exposure site, because

  • radioactive material can stick to their skin and clothes.

  • But once those clothes are removed and

  • their skin is thoroughly washed, the danger is gone

  • even if there's still radioactive material inside them.

  • If they inhaled or swallowed bits of ash,

  • for example, they might have stuff emitting

  • ionizing radiation inside their body.

  • But, even though any radioactive material

  • inside them will continue to give off radiation

  • until it fully decays, that radiation is lost so quickly to nearby cells that the person

  • doesn't pose a danger to others.

  • Basically, it's just hurting them.

  • So, technically, you could go ahead and hug a loved one who's been hospitalized with ARS.

  • But it might not be a good idea to do thatfor their sake.

  • You see, the radiation may have killed off a lot of the stem cells in bone marrow that make white blood cells.

  • And those white blood cells are the immune system's army, so without them, the immune

  • system is weakened and the person is vulnerable to infection.

  • Plus, damage done to other tissueslike connective tissue and blood vesselscan

  • eventually cut off the bone marrow's blood supply.

  • And without blood, the bone marrow keeps dying even after the radiation threat has passed.

  • Eventually, the body can't compensate for the cell damage anymore.

  • And that that point, the person enters the manifest illness stage.

  • This stage lasts anywhere from a few hours to several months, and looks different depending

  • on the kinds of tissues that were damaged.

  • Some forms of radiation syndrome show up in the skin, which can get dry, red, or itchy,

  • or in severe cases can start to blister.

  • Basically, it's the same idea as a sunburnthough, potentially, a lot worse.

  • Other forms, triggered by smaller doses of radiation, mostly affect the bone marrow,

  • resulting in internal bleeding, a drop in white blood cells, and anemia.

  • But if a person is exposed to more than 10 grays of radiation, advanced phases can also

  • have gastrointestinal effects, like severe diarrhea, vomiting, or becoming unable to

  • absorb the nutrients in food.

  • And if the exposure was more than 50 grays, the patient could move really quickly through

  • all the earlier stages to reach the manifest illness stage in a matter of hours.

  • And in cases like these, damage occurs to the central nervous and cardiovascular systems,

  • resulting in convulsions or comas.

  • Andthere isn't really any chance of survival.

  • But, the good news is, in most of those lower-dose scenarios, a person can recoverespecially

  • if they receive prompt treatment.

  • Though, there is no silver bullet.

  • Hollywood seems to think all you have to do to survive a nearby nuclear disaster is pop some iodine tablets.

  • Don't get me wrong, iodine tablets are great.

  • And it's true these pills are recommended as soon radiation exposure is suspected.

  • But they're not a cure-all.

  • In fact, they don't so much treat ARS as prevent the person from absorbing too much

  • radiation in their thyroidthat walnut-sized, H-shaped organ in your neck.

  • See, the thyroid's job is to take iodine and use it to make thyroid hormones, which

  • help regulate your metabolism, among other things.

  • Most of the time, that's totally fine.

  • But if you've been in a fallout zone, you might have radioactive forms of iodine in

  • your bodylike iodine 131, which is one of the radioactive elements made in a nuclear reactor.

  • And if a bunch of that gets into your thyroid, it can cause a lot of DNA damage and even

  • lead to thyroid cancer.

  • Iodine pills contain potassium iodide, a stable form of iodine.

  • The hope is that your thyroid absorbs it instead of the radioactive stuff.

  • And for that reason, they do helpbut they only really protect the thyroid, because it's

  • the body part that sucks up most of the iodine in your body.

  • And they don't help your body deal with any other radioactive elements.

  • Plus, they don't actually do anything to the radioactive material.

  • And if a person has radioactive stuff inside themwhat doctors call internal contaminationgetting

  • rid of it will help minimize the total damage done, so that's an important part of treating ARS patients.

  • Radioactive elements do eventually stop emitting radiation on their own, of course.

  • Radioactive iodine, for example, has a half life of about eight daysso even if it's

  • still in a person's body, after 8 days, it's lost half of its radioactivity.

  • But it takes almost two months for it to lose 99% of its radioactivity, and other radioactive

  • elements have much longer half-lives.

  • And remember, they're emitting cell-damaging radiation that whole time.

  • So it's not ideal to just wait things out.

  • That's why, to speed things along, doctors might give a patient substances like radiogardase

  • or DTPA, which bind to radioactive metals to stop them from entering cells and block them from emitting radiation.

  • Once bound, they'll leave the body in urine or feces.

  • Even then, though, the whole process of totally removing radioactive material from a person's

  • body can take several weeks or even years.

  • And it doesn't treat the damage already done.

  • Actual treatments for ARS might include transfusions

  • to replace the blood cells that were damaged or destroyed by radiation, and cytokine therapy

  • to stimulate the bone marrow to make more white blood cells.

  • Many patients are also given antivirals and antifungals to prevent infections while their immune systems are weakened.

  • And hopefully, with enough medical support, the person will reach the final stage: recovery,

  • where things pretty much go back to normal.

  • So yeah, radiation sickness can be really bad, but even without iodine tablets, people can recover.

  • That's different from a lot of what you see in movies or TV shows, where basically

  • anyone exposed to radiation dieseven if they only left the bunker for a minute, or

  • were miles away on a bridge watching the fallout.

  • In fact, actual cases of ARS are really rare.

  • And that's in part because the events that lead up to them, like nuclear bomb blasts

  • or reactor meltdowns, are thankfully rare.

  • But it's also because you have to be pretty close to the action to get ARS.

  • For example, as awful as the Chernobyl accident was, cases of ARS were limited to people who

  • worked in the plant or who went on-scene as emergency responders, and most of them actually didn't get ARS.

  • There were no confirmed cases in the residents of the closest town.

  • Of course, the rareness of ARS is part of why we didn't really know a lot about radiation

  • sickness or how to treat it when some of the most inaccurate movies or shows were filmed.

  • So they really may have thought that people with ARS were emitting tons of radiation,

  • for example, though we now know better.

  • And even today, myths from the past can persist because we don't really see ARS cases in our everyday lives.

  • Also, some things are just a whole lot less entertaining if they're portrayed accurately.

  • Like, we wouldn't have superhero movies if we let reality get in the way of a good origin story.

  • So maybe we can forgive our favorite filmmakers for not getting all the details 100 percent right.

  • Maybe.

  • Of course, science fiction doesn't always get things wrong.

  • And if you liked learning about the scientific realities behind these TV tropes, you might

  • like our episode on 5 Sci-Fi Futures We Actually Should Worry About.

Radiation sickness might sound like something

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映画やテレビで放射線病を間違える方法 (How Movies and TV Get Radiation Sickness Wrong)

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    Jerry Liu に公開 2021 年 01 月 14 日
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