It will be radioactive forever. The question is where you put the threshold, which is fairly arbitrary.
How is Chernobyl safe for wildlife now, but this book is still dangerous?
Um, Chernobyl is still extremely radioactive. You probably mean the exclusion zone which is really not that bad, there’s even tourists going there. But it’s still not recommended to live there due to cumulative exposure.
Marie Curie studied radioactivity with pure and very active materials with no protection. The radioactivity of the notebook is indirect radioactivity, that is material that becomes radioactive after being exposed to powerful ionizing radiations. It must be noted that the notebook may not be deadly radioactive. And if it will be for 1500 years, it won’t be deadly for 1500 years. For reference, bananas tend to be radioactive too. And you are exposed to ionizing radiations when you take the plane.
Chernobyl had two reactors burn iirc. Most of the radioactive material was in the reactor, but the fire made smoke out of radioactive materials. The quantity of smoke, in kg, that go out was significant, but it got diluted in the atmosphere and spread. Which means there wasn’t so much dust, in mass, that got in any one place. The dust is also not only uranium, but a combination of uranium and materials that were contaminated like the notebook. With the rain, the dust was washed and distributed more, and with the time, materials become less and less radioactive.
Both the book and chernobyl are not dangerously radioactive. But because of the nature of radioactivity, care must always be taken.
Ionizing radiation can’t produce secondary radioactivity in materials…
Well, maybe explain my confusion then, instead of being an ass.
So there’s four types of radiation: alpha, beta, gamma, and neutron. When you’re talking about radioactive materials, it’s almost exclusively the first three. In addition to the inherent danger of the object itself, there’s also the danger of radioactive contamination: not making other things radioactive, but shedding bits of themselves as dust and then that dust getting on other things, or getting ingested/inhaled by humans.
Active fission reactions, like what goes on in the core of a nuclear reactor (or perhaps messing around with some plutonium and a screwdriver), produce neutron radiation. Neutrons can make other things radioactive, via a process called “neutron activation”, whereby the neutrons bind to the material and change some of the atoms into radioactive isotopes.
I hope that helps, and feel free to ask me anything else about radiation. I have some education about it thanks to my job, and I’m always happy to help other people understand it more as well.
