Something that is radioactive has radiation. It is... teeny tiny particles that carry a lot of energy. Many amazing things can be done with radiation - it can power machines or be turned into a weapon - and tiny amounts are present all the time.
But in big doses it is poisonous to humans and some other organic creatures. It can make people very sick - and worse, make any children they might have later on even worse.
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But in big doses it is poisonous to humans and some other organic creatures. It can make people very sick - and worse, make any children they might have later on even worse.