Radiation vs Radioactive Atoms

There seems to be confusion about what radiation is and where it comes from. Many people believe it is the radiation that comes directly from nuclear power plants that poses a threat to public safety. In fact it is the radioactive atoms, which can escape in the event of an explosion, that pose a safety risk. They can be scattered by the wind over hundreds of kilometres. Then they may be ingested or breathed in. If they release radiation at this point, it is damaging to the body's molecules and cells because the radiation is delivered directly to tissues.

[MrEDMeaner]

Interesting and informative video, definitely helpful for someone who lacks this kind of scientific knowledge. But what strikes me most, is the development of your abilities as a presenter and also as a video editor. As someone who has been following your channel for perhaps a year it seems to me, looking back at your older videos now, that you have really honed your craft and become a presenter who is even more accessible and engaging. Well done!

[rdoetjes]

Finally someone who talks sense about IONIZING radiation.

I handle Cesium-137 and Strontium-90 test sources on a bi-daily basis and even Uranium ore that I have sitting in my cabinet about 1 meter away. I don't fear this test sources at all because they are nicely encased in a plastic disk. The urianium ore I am far more careful with even though the radiation is less. Because of the fact that tiny fragments can (and do) come of from time to time and those can be ingested (which is not that worrisome because normally you'd pooh them out within the day and damage is minimal to none). Inhaling is a different issue all together.

I have people cringe (like I do when people own snakes) when they come in my place and see the uranium ore, the americium (which I make the feel even more uneasy saying that it is a decay product from plutonium) and some of my quantum random number generators that are stacked up ready to be send.
I show them that these (made with Cesium-137 test sources) do indeed emit some gammas and they go white from fear. Then on a nice sunny day I say take the meter and let's go outside and they counts go higher than in the house with the radioactive test sources. Simply because of the solar radiation and the amounts of thorium in the sand. Beaches are a wonderful place to get some high readings.

[veritasium]

gamma radiation is an interesting case because it penetrates through a lot of matter before being absorbed but that also means it does not frequently interact with your atoms. So you would need more shielding to block it, but much of it would pass through you and do no damage. The worst case is if you eat significant amounts of radioactive atoms because that exposes you to nuclear radiation from the inside for a long period of time.

[abubardewa]

This is only the youtube channel that I could watch all day long... Great job sir

[adamconrad]

I love how to see the difference of him now and a decade ago, you can really see the growth in confidence in his speech as well as how more interactive he is in his videos than before. They've only been getting better and always have been great content for science junkies like me.

[PapiJack]

It's interesting to watch your older videos and see how your style has changed. Thanks man!

[veritasium]

@HayZing I think mainly because neutron radiation is not very common. Virtually all radioactive atoms decay by emitting alpha, beta, or gamma rays. The only place where one would find a significant number of neutrons is in a nuclear reactor.

[veritasium]

@DaffyDaffyDaffy33322 @TiagoTiagoT Atoms that are not radioactive CAN become radioactive but only under unusual circumstances like neutron radiation. Neutrons can easily be captured by the nucleus because they are uncharged. This makes the atom into a different isotope, which may decay by emitting nuclear radiation. Also, it is not 'elements' that are radioactive, but 'isotopes'. All elements have radioactive isotopes, but some have no stable isotopes - these are noted on the Periodic Table

[pauluk]

Thank you for clearing that up. I couldn't put up with hearing the term 'radiation' being used in the news because I always thought (from my school days) the correct term was 'radioactivity' - and that 'radiation' simply referred to everything from x-rays to radio waves (including visible light). So the media HAVE been using essentially the wrong term all along.

[themantrevor]

Dir sir, thank you so much for this video. I did a senior thesis about nuclear power. A major portion of my thesis was dedicated to this misunderstanding and what it meant to the nuclear industry. Thank you for making the world more enlightened about radiation.

[urbanelemental]

Thank you for doing this video. I've been trying to explain that to people. Radiation versus contamination.

[KarbineKyle]

The blonde lady with the glasses was referring to the inverse square law. Alpha particles (helium-4 nuclei) have null effect on the outside, but do a lot of damage on the inside than beta or gamma. Beta (electrons) can be absorbed by a few mm of aluminum or copper for example. Gamma loses its energy along each time it interacts with matter. It's electromagnetic radiation. About 55% of everyday radioactivity comes from Radon + decay daughters. I'm a nuclear enthusiast, so I'm familiar with handling, studying, and storing radioactive materials. Radioactivity makes many people cringe, and those people usually don't even understand the basics of radioactivity. Plutonium-239 is essentially a pure alpha emitter. Strontium-90 is essentially a pure beta emitter, and Cesium-137 is a beta emitter, but it releases gamma rays when its metastable isomer, Barium-137m decays to stable Barium-137. Each specific radionuclide emit different energies of different particles in different percentages, even if it's the same mode of decay.

[Vulcapyro]

Oh my god Derek. I was extremely involved with the events of the Tohoku Earthquake, and this was a key topic that was fundamentally misunderstood by people all around the world, including the majority of the people it actually affected at the time. You would not believe how often I had to explain to people how nuclear plants work, what they do and don't do, the difference between radiation and radioactivity, etc. Even though this was a year ago, thank you so much for this video.

[pavelZhd]

1:20 - The problem is not "radiation not being able to pass through air". It's more of "Radiation not hitting the detecter" because it's going Upway, Downways or sideways of it.
If we imagine thar radiation is spreading like a wavefront (which is usually counted as sphere) then detectable radiation is on that fitting in an area of fixed size. The amount of radiation detected is thus a ratio of this area, to total area of sphere (since total radiation in a front is constant). So as we move away from center, this ratio get less and less. Proportianally to R times -2.

And the whole thing after this is... not totally true either.
DNA is a rather complex molecule. Long, swilrly and all. And thus it is easy to breack if an external force applied to it. And alpha and beta radiation actually have enough penetration power to reach out DNA and hit it, potentially damaging it.
All by itself, it's not a big deal. Our cells have a built-in mechanism to fix damage, by actually storin two copyes of each DNA, and most of time those copies are tied together, supporting each other, so if one get's damaged, it can easily repair according to it's copy.
The problem starts when you get somwhere where a rain of radiation is that heavy, so having both copyes damaged simultaniously becomes relatively possible. And that is when you start having "radiaction sickness".
The light version is when you have a limited amount of damaged cells. They will die off, but eventually your neiboring cells will replace them with new ones.
In heavy version you get so many cells dead because of DNA damage, you are unable to replace them and you die.
And Ther is also a really trycky third varian where a damaged cell is damaged in a way, so that it can live on, but will behave differently. And in that case there is a small chance that this cell will be more livable than it's neiboring cells. But not performing it's intended role. So that is stars replacing it's neiboring cells with copies of itself. That is when you get Cancer.

Phew... that was some wall of text.

[Demonicalex]

Stop disliking this guy for having his opinion. This is a very nice conversation and people will want to read it. So stop disliking because later on his comments will disappear.

[duragtj]

who's watching this for school because of coronavirus

[FunGA]

The term your describing is Contamination. Radioactive particles in an unwanted place.

[larrytaco]

i really like this you interview really intelligent people unlike most other shows of this sort

[MMBrown]

Atoms exposed to the neutron flux emitted by the reactor have their basic particles knocked around (or absorb the neutron). They loose/gain particles from this, and because they want to become stable, they start emitting their own particles trying to return to a nominal state. This is how they become "activated", and are now radioactive.

[brands]

watch the video again, then ask your question.